Final Report Summary - INTHEAT (Intensified Heat Transfer Technologies for Enhanced Heat Recovery)
Executive Summary:
The FP7-SME-2010-1 project “Intensified Heat Transfer Technologies for Enhanced Heat Recovery- INTHEAT” was running Dec 2010 - Nov 2012. As an SME-oriented project, it was focused on development of innovative technologies by RTD participants for the benefit of SME partners. The Consortium included ten partners: 4 Research Centres of Excellence, 5 European SMEs, including 3 heat exchange equipment manufacturers, 1 heat recovery system software developer and also 1 industrial user.
The core part of the Project was the development of methodologies to select and rigorously engineer the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they have confidence.
The most efficient way to decrease energy consumption and the release of greenhouse gases from the process industries is to increase heat recovery. The cleanest energy is the energy saved by improved efficiency. Whilst heat recovery is widely practised, it is almost never carried out to its maximum potential.
This project identified the maximum potential for heat recovery and allowed considerable improvement in heat recovery through the application of process intensification approach and associated equipment. The conventional heat exchanger technology used in the process industries is mature, and yet various new ways have recently been developed to significantly enhance heat exchanger performance. These new techniques do not need to be applied through the whole heat recovery system, but mainly at those critical parts that limit the system performance. Novel techniques need to be developed and exploited to improve the performance of existing systems, as well as improve the performance of new plant design. This project will develop an approach to the improvement of heat recovery by considering the total energy systems and identifying appropriate places to apply the new intensification technology to make a step change improvement in heat recovery.
As a result of the Project, the SME Partners:
- Were able to enhance their understanding of heat exchange under fouling;
- To apply technical innovation for heat transfer intensification for heat recovery;
- To better understand the properties of new materials used in heat exchnage;
- Adopted a innovative methodology for combining heat transfer innovative design with process (mainly heat) integration;
- Received a software toolbox for heat exchanger network design and retrofit based on the innovative methodology and were trained to use the software;
- Validated the methodology and the toolbox on industrial case studies.
The Project results were extensively disseminated during the Project life span.
Project Context and Objectives:
The most efficient way to decrease energy consumption and the release of greenhouse gases from the process industries is to increase heat recovery. The cleanest energy is the energy saved by improved efficiency. Whilst heat recovery is widely practised, it is almost never carried out to its maximum potential. In major process industries including oil refining, petrochemical processes, food, cement, steel, pulp and paper, where very substantial energy savings can be made, heat recovery through enhancement has not yet made a significant impact. This project aims both to identify the maximum potential for heat recovery and to allow a step change improvement in heat recovery through the application of process intensification approach and associated equipment. The conventional heat exchanger technology used in the process industries is mature, and yet various new ways have recently been developed to significantly enhance heat exchanger performance. These new techniques do not need to be applied through the whole heat recovery system, but mainly at those critical parts that limit the system performance. Novel techniques need to be developed and exploited to improve the performance of existing systems, as well as improve the performance of new plant design. This project will develop an approach to the improvement of heat recovery by considering the total energy systems and identifying appropriate places to apply the new intensification technology to make a step change improvement in heat recovery.
One of the biggest energy consumers in the process industries is crude oil distillation. Calculations indicate that the energy consumption could be decreased by 30% purely by using intensification technology in the critical parts of the heat recovery system. Such changes would both enhance the economic performance of European industry and also make a significant reduction in greenhouse gases in a very cost effective way. Until now identification of energy saving opportunities and their location in complex process plants has been carried out by the use of ‘energy accounting’ procedures through the application of techniques, such as pinch analysis. These complex ‘top down’ studies provide plant operators with basic information on where to place new or re-locate existing exchangers to benefit improved energy recovery. Since the inception of pinch technology some 20 years ago, the outcomes have almost without exception exploited heat exchange equipment of the more traditional, low thermal efficiency, type. These commonly used studies have not addressed the use or taken into account the significant benefits available from enhanced, state-of-the-art, high efficiency exchangers, and have not achieved the maximum possible energy recovery.
By necessity process plants use a wide variety of exchangers and exchanger types to meet the technical demands of very different types of streams, fluid states and phases. Yet these exchangers are mostly variations of the traditional shell-and-tube design. Each potential heat recovery opportunity requires individual consideration in the selection of the appropriate enhancement to meet the required new performance. It is therefore understandable that process plant engineers to date have found difficulty in differentiating and applying the optimum equipment. Uptake of recently-developed technologies in the industry has not been high, due to the lack of confidence and understanding of the new technologies.
A core part of this proposal is the development of methodologies to select and rigorously engineer the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they have confidence.
This collaborative project addresses the technical needs of the industry, responds to socio-environmental pressures on energy consumption and carbon emissions, and supports technology developers and industrial end-users.
A core part of this proposal is the development of methodologies to select and rigorously design the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they will have confidence.
The project resulted in developing of a novel heat exchanger network methodology and a toolbox for energy savings through:
(i) Enhancing our understanding of heat exchange and waste heat recovery;
(ii) Combining enhanced heat transfer innovative design to achieve the synergy of separate novel technologies with focus on conventional, plate and membrane exchangers. Current trends are taken into account that whilst new types of exchangers are making an increasing impact and acceptance in the process industry, the main exchanger types are based around tubular constructions, shell and tubes and air cooled exchangers and that it is likely to remain so for many practical and pressure withstanding reasons.
(iii) Proposing new materials of improved economic and environmental performance
(iv) Implementing the developed technologies effectively in heat exchanger networks (HENs) through intelligent process integration and control techniques.
Project Results:
1. Know-how on experimental fouling
Fouling is fundamentally a complex phenomenon and a broad range of basic fouling mechanisms exist, and hence a range of experimental technologies need to be developed for the investigation of fouling and its mitigation. In the Project, fouling experiments have been carried out over a wide range of conditions using a batch stirred cell system. Negative fouling rates are observable if the surface temperature is reduced and/or the stirring speed is increased after the test surface has undergone a significant amount of fouling, i.e. the fouling resistance has increased to a significant level. The fouling rate data for both positive and negative fouling rates can then be utilized to identify the fouling threshold conditions relatively quickly.
Modification of the geometry of the probe surface with wire attachment or helix threads shows a mitigating effect on crude oil and crystallization fouling, which can be interpreted by intensified turbulence as revealed by CFD simulation.
2. CFD research results on heat transfer enhancement and fouling mitigation
With the help of CFD simulation, the concept of equivalent velocity/Reynolds number is developed such that a fouling model developed for bare round tubes can be extended for use with more complex geometries.
Fouling threshold conditions, predicted by the fouling model with the help of CFD simulation, may provide a guide to avoid fouling or at least to minimise the impact of fouling by operating a heat exchanger under non-fouling conditions.
The proposed method with the help of CFD simulation offers a practical solution for estimation of the average heat transfer coefficient and wall shear stress for tubes fitted with hiTRAN inserts, revealing a significantly enhancement of heat transfer by the inserts, and the influence of the density of inserts on the heat transfer coefficient.
The induction model is valuable to predict the effects of surface temperature and velocity on the length of the induction period.
3. Shell-and-tube exchanger heat transfer enhancement know-how
Shell-and-tube exchanger heat transfer enhancement know-how has been systematised. The information on heat transfer and pressure loss inside tubes fitted with heat transfer performance-enhancing technology was collected. Main types of heat transfer enhancement - the twisted tape, static mixer, helically-coiled wire, core tube and the wire matrix insert - were analysed. It has been shown that the former two insert types are best suited to the laminar flow regime, with helically-coiled wires best suited to turbulent flow, and wire matrix inserts apparently suited well to the transition-turbulent flow regimes, but with proven applications in laminar flow. For the majority of the inserts correlations were presented. The use of a Performance Index for comparison of the thermo hydraulic performance of different inserts was considered. It was demonstrated how using coefficients in equations enable to rapidly determine the heat transfer area reduction that may result from any allowable pressure drop for a certain insert geometry. The influence of the laminar boundary layer, which is considered to be a major inhibitor to heat transfer, was studied, and the removal of which is recognised to be a significant factor in the success of enhancement devices. Optimisation work was described that has demonstrated how heat transfer performance over a flat plate varies with both the distance downstream of a wire protrusion of known thickness, as well as the thickness of the wire in relation to the laminar boundary layer.
4. Mathematical models and the software implementation of tube- and shell side heat transfer enhancement
Tube-side heat transfer enhancement:
The main findings concern the heat transfer and pressure drop data that was obtained from the test rig for a wide range of tube sizes and insert geometries. The empirical correlations derived from this data represent a significant progression in the knowledge of the performance of hiTRAN® inserts, covering almost all of the tube and insert geometries for which the company have been required to give thermal performance guarantees.
The study also presented some qualitative findings in terms of measurement of the pressure drop characteristics of a core wire. Although the function of this study was not to provide a theoretical basis to the notion of a hydraulic core wire diameter, its results may be used to separate the contributors to pressure drop in determining a semi-empirical model.
Also proposed were a number of qualitative studies, aiming to optimise the performance of hiTRAN® inserts, in terms of its geometrical parameters. The loop inclination angle (or, analogously, the coil diameter) was optimised for the most commonly used insert wire combinations inside the two most common tube sizes. This study made a useful contribution to the company’s existing knowledge of optimum coil diameter, and may be effectively used as a basis for further investigations into optimum coil diameter for other tube diameters. Optimisation of the number of turns applied to the core wire during the fabrication of an insert was carried out. This will allow the company to modify their manufacturing procedures The analysis provided on wall fit in this chapter provides a useful basis for further experiments on the quantitative determination of the effect of wall fit.
Internal fins:
Simulations were carried out to test the performance of micro-fins for different heat exchanger configurations. It was found that the overall level of enhancement of the heat exchanger was sensitive to all the studied geometric parameters: fin height and number of fins.
The study of the performance was carried out for different flow conditions within the laminar turbulent region. Based on the obtained results it was possible to conclude flow conditions under which micro-fins are not beneficial and under which conditions they are able to provide a medium-high level of enhancement of the overall heat transfer of a heat exchanger, affecting not only the tube-side heat transfer coefficient, but the overall heat transfer area.
Shell-side enhancement: Shell-side enhancement is achieved when using a non-continuous helical baffle and is more effective when the helix angle is smaller, hence, smaller helical pitch for the same diameter. However, the choice of helix angle should not allow the helical pitch/baffle spacing to drop below the width of the existing segmental ones as this will increase pressure drop levels exponentially. Moreover, higher viscosity fluids are preferred for enhancement as larger heat transfer enhancements would be achieved with a mild increase in pressure drop. In addition, it has been observed that, the pressure drop trend becomes milder at larger helical angles.
Software:
The server application was developed, the HEX Network solver software, which provides information concerning the Geometry, process and property data for each exchanger. With this information the developed dll is able to calculate the corresponding heat transfer and pressure drop results.
5. Know-how on basic configuration framework for plastic heat exchanger units
Basic design parameters of the current Makatec heat exchanger (HEX) model were analysed. The delivered design parameters represent the background for further investigations. The available HEX is presently not configured for the use with sulphuric or hydrochloric acid.
The change to polymer materials which may be exposed to sulphuric or hydrochloric acid offers the company an opportunity to take possession of a new field of application for the HEX.
A promising way towards optimisation of HEX performance is to reduce pressure drop and enhance the volume flow at the same time. This can be achieved by choosing an optimal spacer configuration inside the channels.
6. CFD models and simulation results for plastic spiral heat exchanger
The pressure drop within plastic heat exchanger grids was experimentally investigated and a CFD model describing the fluid dynamics in the spiral wound heat exchanger was developed and implemented. This model was validated using the experimental pressure drop data of Makatec. A satisfactory agreement between simulated and measured values was found.
Using this model, the spacer geometry was varied to identify its impact on the pressure drop characteristics. In particular, the spacer angle α variation and the size of the channels were tested.
7. Optimised results of the geometry and operating conditions for plastic heat exchanger units
- Pressure drop within plastic heat exchanger grids was experimentally investigated.
- A CFD model was developed describing the fluid dynamics in the spiral wound heat exchanger
- The spacer geometry was analysed and its impact on pressure drop characteristics established
- The investigations clearly show that the pressure drop reduction can be achieved by enlargement of the channels within the spacer grid, for instance, applying double layers of spacer grids or spacer grids with larger spacer diameters or bigger distances between the spacer filaments.
- Enhanced heat transfer can be achieved by induced turbulent flow pattern, but with a significantly increased pressure drop characteristics.
8. Design methodology for new heat exchanger networks using P-graph and the ABB (Accelerated Branch-and-Bound) optimisation algorithm - know-how
A novel approach to the design of new heat exchanger networks using P-graph and the ABB (Accelerated Branch-and-Bound) optimisation algorithm was developed. It considers HEN synthesis through the development of generic superstructures that incorporate all the types of the previously investigated heat exchangers, while it will accounts for a generic HEN representation to facilitate HEN interconnectivity. The approach was tested for an industrial case study and showed agreement with experimental data.
9. Retrofit procedure for heat exchanger networks prone to fouling deposition - know-how
A novel optimization method was developed to improve heat recovery in heat exchanger networks (HENs) with intensified heat transfer, and simultaneously considering fouling effects In order to solve large scale HEN retrofit problems efficiently, a new iterative MILP-based method has been proposed. The proposed design approach is able to give realistic and practical solutions for the debottlenecking of HEN as detailed intensified techniques are systematically applied. This leads substantial capital saving as no structural modification in heat recovery system configuration is considered.
To reduce energy consumption of the whole HEN, the retrofit includes the following aggregate steps:
Step 1: Optimize the whole HEN to reduce energy consumption (SA design method).
Step 2: Identify suitable exchangers for retrofit based on the optimal results obtained in Step 1.
Step 3: Identify retrofit strategies (intensifications, new exchangers, or both) in the selected exchangers.
Step 4: Consider detailed performances (heat transfer coefficients and pressure drops) of the selected exchangers.
Step 5: Select suitable intensification techniques (subject to maximum pressure drop restrictions, and required enhanced heat transfer coefficients) on the enhanced exchangers.
10. Software tool for screening and analysis design and retrofit HEN options taking into account the intensified heat exchanger parameters
Based on the integrated methodology described above, a software tool for HEN design and retrofit taking into account heat transfer enhancement technologies and fouling has been developed. A manual and training materials have also been developed and training provided to SME Partners.
11. Know-how of application of spiral plastic heat exchanger for cooling of acids
The investigations clearly show that the pressure drop reduction can be achieved by enlargement of the channels within the spacer grid, for instance, applying double layers of spacer grids or spacer grids with large spacer diameters or bigger distances between the spacer filaments.
Another way to geometry optimisation of the spiral wound heat exchangers is to enhance turbulence and hence heat transfer. In this regard, a grid geometry with interwoven spacers was investigated. The results showed indeed a turbulent flow pattern, but with a significantly increased pressure drop characteristics. It is thus necessary to investigate temperature fields and heat transfer parameters in all studied geometries and compare them. This work will be done in the near future. Further investigations are also going to be performed with regard to new materials which are appropriate for use in sulphuric or hydrochloric acid applications. The change to polymer materials which may be exposed to sulphuric or hydrochloric acid offers an opportunity to open a new field of application for the spiral wound heat exchanger.
12. Know-how of application of the toolbox developed in chemical/petrochemical industry
The demonstration case study was carried out on an existing preheat train for a crude oil distillation column in a refinery plant. The network structure includes 31 heat exchangers and 14 processing streams (3 cold streams and 11 hot streams). The retrofit objective was to reduce the hot utility (HU) consumption, namely, to reduce the heat duty of particular heat exchangers (target exchangers). As a result of application of the methodology and the software developed, the preheat train total utility consumption has reduced by ca 12%, total network operating cost has reduced by ca 4%, retrofit annual profit amounted $570k and CO2 emissions have reduced by 10% with negligible retrofit cost of $54k (the inserts and labour)
13. Know-how of heat transfer intensification for water and energy minimisation
The methodology developed provides significant fuel and hot utility savings which in turn mean hot and cold utility water consumption reduction. For the preheat train case study, the hot utility consumption was reduced by 15% utility consumption. For the crude oil distillation unit with plate frame heat exchangers the hot and cold utility consumption savings reached 10%.
14. Know-how of application of the toolbox developed in food industry
Energy studies have been carried out at three plants of a food company. The biogas utilisation plant has been identified as the most interesting and promising of the three case studies. In that plant, a full HEN retrofit analysis has been performed showing a serious potential for improving both the energy and the economic efficiency of the plant.
- A ca 70% increase in the profit on operational basis has been identified for the biogas utilisation plant, equivalent to 23 k$/y savings from decreased utility cost and increased steam sale revenues.
- The latter can be achieved by installing heat transfer enhancement devices costing ca $11k
- As a result the payback period of the investment is very attractive amounting to ~5 ½ months
The above findings have been also double-checked by performing a sensitivity study, also providing the company with an investment decision tool.
They have been further consulted and have indicated that this is a very promising retrofit suggestion, worth of considering for an investment decision.
Those case studies demonstrated the potential of the developed software tool and the methodology of INHEAT project for implementation by the SMS.
This methodology has been appreciated by all SMS involved in the project and will be providing them a considerable support for their future research and development activities.
15. Know-how of application of the plate exchangers using the software tool in chemical/petrochemical industry
Plate frame heat exchangers are still not widely used in refineries. However, the exchangers that manufactures offer at the market these days have already proved their potential benefits. The feasibility of application of plate frame heat exchangers for atmospheric crude oil unit retrofit was studied using the methodology and the software developed. As a result, the total utility cost has reduced by ca 16%, capital cost by 20%, total network cost by 14%.
Potential Impact:
The objective of the current project was to significantly increase energy efficiency of heat exchangers and their networks throughout different sectors of the process industries by developing methodologies to select and rigorously engineer the appropriate type of enhancement technology applied at a practical level, superior to existing systems in both capital cost and performance. Given that the new heat enhancement systems installed using the proposed methodology have a remarkably lower capital and operating costs it should improve the competitiveness of European end-users especially within the chemical, petrochemical, refinery, food and pulp and paper sectors. Positive impact can be identified for the consortium and industrial companies (SMEs in particular), end-users, broader Community economic and societal development.
Enhanced heat exchanger networks market
Various recent studies show that the world wide shell and tube heat exchanger market is set to grow from just under $1.9bn per year during 2005 ($0.5bn for Europe) to over $3.4bn ($0.65bn for Europe) by 2012, with Middle East and Asia markets offering the greatest growth potential with Europe and the Americas also offering attractive prospects. While the Middle East and Asia Pacific markets are expected to dominate the new build refinery sector, around 67% of the world market for shell and tube heat exchangers will continue to derive from brownfield, retrofit and revamp projects. For Europe, this is expected to grow even higher to 77% of the available market and it is this which offers the most prospects for the deployment of the innovative heat transfer solutions which the current project generated. It will be in this sector where we offer the biggest potential benefits in terms of energy consumption and CO2 emissions derived from the replacement of older, inefficient units with state-of-the-art technologies. While it is certainly already a substantial potential market for companies such as Cal Gavin and EMBAFFLE BV and, the further process intensification and heat transfer performance enhancement synergies that are expected from the combination of these and other complementary technologies including finned and profiled tubes will undoubtedly lead to even faster uptake by the market as the benefits from this work become more widely disseminated. We estimate that successful outcome of the INTHEAT could improve the potential year on year growth patterns of these and associated companies working in this area by 15-20% Compound Annual Growth Rate (CAGR) over the five year period compared with where the respective companies would be without this work being carried out. By far and away the greatest benefit will come from the application of these new process intensification/integration technologies in the reduction of energy consumption and CO2 emissions as a result of the very significant improvements in operating efficiencies and working practices from across new and existing plants.
Expected impact
The project delivers a comprehensive methodology for developing new and improving existing heat exchanger designs to significantly enhance their energy and environmental performance. The direct impact is the considerably improved cost effectiveness and increased competitiveness in the world market. The following impact contexts can be distinguished:
• General profit for the industry
• Positive impact on the project partners business and research performance
Positive impact on the industry
The expected impacts on industry are increased energy and cost efficiency, reduced environmental impact and improved availability of the energy saving measures. They will be both positive effect on the Small-to-Medium Enterprises and that on the large-scale industry. The improvement of the energy efficiency has been already registered in the range from 12-16% in larger companies in refining and petrochemical sectors and up to 40% and more for smaller-scale enterprises in eg food sector. The reason for this is that in most cases, the European heavy industry has already energy efficiency improvement measures. These measures have been made possible by the larger sites/space and capital availability. In smaller companies, energy recovery measures have been still considered too costly due to the smaller available budgets and have not been a given a clear go ahead. The potential savings in energy costs and carbon footprints are of similar magnitude. The decreased energy demands will also enable SMEs to consider small-scale local energy resources, including renewable ones, which will further limit the net rate of CO2 emissions.
Another important impact in this regard is benefits for end-users if the developed technologies from the current project are implemented. The refining industry is taken as an example. The huge costs currently associated with fouling in heat exchangers can be categorised as follows:
• Energy costs and environmental impact. In refining this corresponds to the additional fuel required for the furnace due to the reduced heat recovery in the preheat train as exchangers foul. Energy losses due to increased pressure drop (pumping power) may also be significant. The use of more fuel leads to additional production of CO2 with the associated environmental impact. Total amount of CO2 generated due to fouling is approximated 2.5% of the total anthropogenic CO2 emissions, and this crude oil fouling accounts for about 10% of total CO2 carbon footprint of refinery industries. Another environmental impact is the discharge of chemical agents used for fouling inhibition and cleaning.
• Production loss during shutdowns due to fouling. For instance, If a crude oil pre-heat train is furnace-limited, a typical 10% loss of production due to taking a heat exchanger out of service in a 100 000 US barrel/day plant would cost $20 000 US per day (assuming $2 per US barrel of marginal lost production). After shutdown, there is an additional cost due to out-of-specification production after production is restarted. The methodology developed reduces the shutdowns caused by fouling.
• Capital expenditure. This includes excess surface area, costs for stronger foundations, provisions for extra space, increased transport and installation costs, costs of anti-fouling equipment, costs of installation of on-line cleaning devices and treatment plants, increased cost of disposal of the (larger) replaced bundles and, finally, the (larger) heat exchangers.
• Maintenance costs. This includes staff and other costs for removing fouling deposits and the cost of chemicals or other operating costs of anti-fouling devices. There are also economic and environmental penalties associated with disposal of cleaning chemicals after cleaning. What has been shown, in detail, is a typical application of tube-side enhancement from a current live refining project. The results show the preheat train total utility consumption reduction by ca 12%, total network operating cost reduction by ca 4%, retrofit annual profit of $570k and CO2 emissions reduction by 10% with negligible retrofit cost of $54k (the inserts for exchangers to be enhanced and labour)
Developing new concepts for radically improving energy and capital efficiency
This project will have a significant impact in terms of energy and capital efficiency improvement by proposing new concepts in the design of heat exchangers. The development of heat exchangers using polymer materials is one such case. As a result of the project, the efficiency of heat recovery systems is expected to increase. They also cost fundamentally lower than the shell-and-tube exchangers, which makes energy saving a much more affordable option. This is expected to boost the interest of industry and especially SMEs to energy saving projects, involving reduced fouling and the discussed advanced heat exchangers.
New concepts were also developed in addressing the effects of fouling in heat exchangers. The use of CFD methods offers a rigorous representation and in-depth understanding of the underlying fouling causes and result in methods of predicting and designing heat exchangers of limited susceptibility to fouling. Fouling is also addressed in the design of heat exchange networks by appropriately manipulating HEN design and control variables that lead to prevention of fouling. Research in this area resulted in novel methods that enable the quantification of fouling effects in both individual heat exchanger equipment as well as entire heat exchanger networks. Industrial heat exchanger equipment developers and users will be able to capitalize on this work to eradicate fouling from their processes.
The databases on heat exchangers optimal duty and process streams parameters and heat transfer enhancements for wide variety of industries will stipulate the development and manufacturing of new more efficient and competitive constructions by different producing companies, even the smaller ones. This will lead to increase of competition in the area of energy efficient heat transfer equipment manufacturing and marketing with consequent decrease in prices. In turn such situation will stipulate the acceptance of such equipment by process industries and engineering companies and will contribute to long term effects of energy saving and CO2 emissions reduction according to EC targets for year 2050.
Effect on the project partners
The multidisciplinary team of the project consortium has considerably benefitted in terms of expertise and knowledge exchange from the project. The industrial partners were able to increase their energy-saving and technology development efforts, to extend their networks, better exploit the research results and acquire technological know-how, bridging the gap between research and practice. This strengthened the academic partners’ research and innovation capacity and their own contribution to the development of new technology-based products.
The optimal combination of science and private initiative, the science being the source of knowledge, and the private initiative that of technological, economic and managerial experience has been useful for both sides: it promoted penetration of the scientific accomplishments into the business and inspired the advancement of new inter-disciplinary knowledge in the scientific community.
Benefits for Industrial SME Partners
CALGAVIN expects a 1.5 times increase in its turnover from increased sales of improved and new type heat exchanger technologies as a result of the project. CALGAVIN, EMBAFFLE, OIKOS and PIL will be able to provide engineering consultancy to the processing industry in Europe and world-wide.
While considering benefits to industrial SME Partners, it is necessary to account for several important factors:
• Many of the European enterprises are in need to significantly improve their direct environmental performance via decrease of CO2 emissions. Enterprises are also pushed to continually reduce their consumption of fossil-fuel-derived energy dictated by the climate change regulations.
• Given the strong competition on the chemicals market, they also look for every measure which will cut down their bills and reducing energy by better energy recovery is always an excellent opportunity, especially in the view of crude oil prices rising to US$ 130/bbl and higher.
• A large number of new start-ups and chemical site re-openings take place in Central and Eastern Europe and most of these plants are in a great need of new technologies, especially in terms carbon emissions and energy recovery.
• Consequently, only in Europe alone there is a market for heat transfer engineering and energy recovery services amounting to at about 2-5 billion EUR per year.
Benefits for Research Partners
The RTD performers benefitted from the collaboration throughout the project and after. One important impact was strengthening the links between the academic centres via the establishment and development of a common methodological and software platform for industrial innovation. The synergy between the expertise in targeting-based Process Integration (UNIMAN), combinatorial network optimisation research (UNIPAN), computational fluid dynamics (UNIPAD), and fouling experiment and analysis (UNIBATH) has produced improved system designs and brought about wider horizons of all RTD performers involved. Concerted dissemination activities meant that along with the uptake by the industry, research institutions primarily in Europe have been aware of the Project and its activities and a wide network of business relations in the field has been established.
Benefits for potential end-users
Significantly reduced utility consumption is the major benefit for the end users. Improved heat transfer and energy integration, with increased heat recovery of about 15-20% in particular translate into up to 20% reduction in their overall operation costs. The SME partners are expected to benefit through increase of their engineering, consultancy and manufacturing business activities in the ballpark of 1.3 – 2+ of their incomes after the end of the project. This estimate is convincingly supported by a publicly available report about a production site in the United States – the 3M Hutchinson production site, where from 7 MM$/y initial energy expenses, only the applied energy recovery from the RTO units brings savings of approximately 0.7 MM$/y. This is 10% cost reduction only from the heat integration. Given the contemporary globalised market conditions such a cost reduction could result in market share increases comparable with the SMEs current turnovers. Basically, if the cost efficiency improvement potential is implemented, the only factor limiting the SME partners’ turnover increase would be mainly the availability of funds/credits and the enterprises’ management capabilities.
Longer term impacts on the consortium
The SME partners will derive their benefits from the outputs of the project primarily as vendor of the finished enhanced heat transfer equipment and/or as providers of specialised engineering design solutions based on the methodology developed and through expansion of their consultancy activities. There will be additional benefits shared within the partnership in form of a transnational network that will help penetrating markets across the EU and globally. The specific benefits, apart from economical benefits, for each partner are briefly summarised below: The calculated jobs gained by implementing INTHEAT will be spread between the consortium members, sub-contractors and suppliers, with the majority going to CALGAVIN, EMBAFFLE, PIL and OIKOS, which can boost production to follow projected sales. In total, we expect to have created 25 new jobs throughout the SME consortium by the end of year 5 post-project based on assumptions of current turnover and labour intensity. In addition to this, at least an equal number of jobs are likely to be created with third party sub-suppliers. In conclusion, INTHEAT has been economically justified for all participating industrial partners, all of which gaining payback of their initial investment within a reasonable time horizon.
Time-to-market
Before the consortium can enter the market, it initiated knowledge protection procedures. Successful outputs will help to attract investors for the upscaling of production, alongside the demand effects to be expected from a successful demonstration by end-users.
On the supply side, once protection procedures for critical IPR have been completed, the consortium will begin planning of capacity and possible expansions. Production is expected to start incrementally, the consortium being capable of supplying systems themselves for at least the first 3 years post-project according to the market analysis stipulated.
Benefits to the EU and political/societal aspects
In addition to the benefits for process industry and the consortium, we also investigate the impact at the third and final level, i.e. the positive societal effects of the project in a number of areas, also supporting European policies. The main rationale and opportunity is to produce a novel enhanced heat exchanger design and retrofit methodology, which is much beyond the state-of-the-art in overcoming current market and technical barriers.Itr provides significant advantages in terms of both performance and economics to end-users, and at the same time contributes significantly to meeting EU policy objectives, especially within Energy/CO2 Environment emissions field.
Build-up of dirt deposits, or fouling, on the metal surfaces of petrochemical plant heat exchangers is a major economic and environmental problem worldwide. According to IHS estimates have been made of fouling costs due primarily to wasted energy through excess fuel burn that are as high as 0.25 per cent of the gross national product (GNP) of the industrialised countries. With oil prices at record highs, the payback from fouling reduction by increased throughput and less wasted fuel increases year on year. Many millions of tonnes of carbon emissions are the result of this inefficiency. Costs associated specifically with crude oil fouling in the pre-heat trains of oil refineries worldwide are estimated to be of the order of $4.5bn (http://uk.ihs.com/news/overcoming-effect-oilfouling.htm). Following these estimates, the EU losses from fouling constitute 42,075 million 2007 USD. The project will provide solutions which will enable to reduce those losses by 25- 35 %. For the countries where participating Partners are planning to primarily exploit the results of the project the loss reductions are estimated as follows (Table 1). Successful completion of INTHEAT goals will be considerable contribution to the implementation of Directive on eco-design requirements for end-use energy-using products (2005/32/EC, O.J. L 191of 22.7.2005) and the Directive on energy end-use efficiency and energy savings (2006/32/EC, O.J. L 114 of 27.4.2006).
Table 1. Estimated fouling caused loss reductions in some countries:
Country - Fouling caused loss reductions, MM USD 2007
Czech Republic - 131
Germany - 2,492
Greece - 236
Hungary - 104
Italy - 1,578
Slovakia - 56
Spain - 1,079
The Netherlands - 577
UK - 2,079
Ukraine - 1,005
List of Websites:
www.intheat.eu
The FP7-SME-2010-1 project “Intensified Heat Transfer Technologies for Enhanced Heat Recovery- INTHEAT” was running Dec 2010 - Nov 2012. As an SME-oriented project, it was focused on development of innovative technologies by RTD participants for the benefit of SME partners. The Consortium included ten partners: 4 Research Centres of Excellence, 5 European SMEs, including 3 heat exchange equipment manufacturers, 1 heat recovery system software developer and also 1 industrial user.
The core part of the Project was the development of methodologies to select and rigorously engineer the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they have confidence.
The most efficient way to decrease energy consumption and the release of greenhouse gases from the process industries is to increase heat recovery. The cleanest energy is the energy saved by improved efficiency. Whilst heat recovery is widely practised, it is almost never carried out to its maximum potential.
This project identified the maximum potential for heat recovery and allowed considerable improvement in heat recovery through the application of process intensification approach and associated equipment. The conventional heat exchanger technology used in the process industries is mature, and yet various new ways have recently been developed to significantly enhance heat exchanger performance. These new techniques do not need to be applied through the whole heat recovery system, but mainly at those critical parts that limit the system performance. Novel techniques need to be developed and exploited to improve the performance of existing systems, as well as improve the performance of new plant design. This project will develop an approach to the improvement of heat recovery by considering the total energy systems and identifying appropriate places to apply the new intensification technology to make a step change improvement in heat recovery.
As a result of the Project, the SME Partners:
- Were able to enhance their understanding of heat exchange under fouling;
- To apply technical innovation for heat transfer intensification for heat recovery;
- To better understand the properties of new materials used in heat exchnage;
- Adopted a innovative methodology for combining heat transfer innovative design with process (mainly heat) integration;
- Received a software toolbox for heat exchanger network design and retrofit based on the innovative methodology and were trained to use the software;
- Validated the methodology and the toolbox on industrial case studies.
The Project results were extensively disseminated during the Project life span.
Project Context and Objectives:
The most efficient way to decrease energy consumption and the release of greenhouse gases from the process industries is to increase heat recovery. The cleanest energy is the energy saved by improved efficiency. Whilst heat recovery is widely practised, it is almost never carried out to its maximum potential. In major process industries including oil refining, petrochemical processes, food, cement, steel, pulp and paper, where very substantial energy savings can be made, heat recovery through enhancement has not yet made a significant impact. This project aims both to identify the maximum potential for heat recovery and to allow a step change improvement in heat recovery through the application of process intensification approach and associated equipment. The conventional heat exchanger technology used in the process industries is mature, and yet various new ways have recently been developed to significantly enhance heat exchanger performance. These new techniques do not need to be applied through the whole heat recovery system, but mainly at those critical parts that limit the system performance. Novel techniques need to be developed and exploited to improve the performance of existing systems, as well as improve the performance of new plant design. This project will develop an approach to the improvement of heat recovery by considering the total energy systems and identifying appropriate places to apply the new intensification technology to make a step change improvement in heat recovery.
One of the biggest energy consumers in the process industries is crude oil distillation. Calculations indicate that the energy consumption could be decreased by 30% purely by using intensification technology in the critical parts of the heat recovery system. Such changes would both enhance the economic performance of European industry and also make a significant reduction in greenhouse gases in a very cost effective way. Until now identification of energy saving opportunities and their location in complex process plants has been carried out by the use of ‘energy accounting’ procedures through the application of techniques, such as pinch analysis. These complex ‘top down’ studies provide plant operators with basic information on where to place new or re-locate existing exchangers to benefit improved energy recovery. Since the inception of pinch technology some 20 years ago, the outcomes have almost without exception exploited heat exchange equipment of the more traditional, low thermal efficiency, type. These commonly used studies have not addressed the use or taken into account the significant benefits available from enhanced, state-of-the-art, high efficiency exchangers, and have not achieved the maximum possible energy recovery.
By necessity process plants use a wide variety of exchangers and exchanger types to meet the technical demands of very different types of streams, fluid states and phases. Yet these exchangers are mostly variations of the traditional shell-and-tube design. Each potential heat recovery opportunity requires individual consideration in the selection of the appropriate enhancement to meet the required new performance. It is therefore understandable that process plant engineers to date have found difficulty in differentiating and applying the optimum equipment. Uptake of recently-developed technologies in the industry has not been high, due to the lack of confidence and understanding of the new technologies.
A core part of this proposal is the development of methodologies to select and rigorously engineer the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they have confidence.
This collaborative project addresses the technical needs of the industry, responds to socio-environmental pressures on energy consumption and carbon emissions, and supports technology developers and industrial end-users.
A core part of this proposal is the development of methodologies to select and rigorously design the appropriate type of enhancement technology into energy optimisation studies to a practical level, whereby process plant engineers can plan and carry out plant energy reduction programmes in which they will have confidence.
The project resulted in developing of a novel heat exchanger network methodology and a toolbox for energy savings through:
(i) Enhancing our understanding of heat exchange and waste heat recovery;
(ii) Combining enhanced heat transfer innovative design to achieve the synergy of separate novel technologies with focus on conventional, plate and membrane exchangers. Current trends are taken into account that whilst new types of exchangers are making an increasing impact and acceptance in the process industry, the main exchanger types are based around tubular constructions, shell and tubes and air cooled exchangers and that it is likely to remain so for many practical and pressure withstanding reasons.
(iii) Proposing new materials of improved economic and environmental performance
(iv) Implementing the developed technologies effectively in heat exchanger networks (HENs) through intelligent process integration and control techniques.
Project Results:
1. Know-how on experimental fouling
Fouling is fundamentally a complex phenomenon and a broad range of basic fouling mechanisms exist, and hence a range of experimental technologies need to be developed for the investigation of fouling and its mitigation. In the Project, fouling experiments have been carried out over a wide range of conditions using a batch stirred cell system. Negative fouling rates are observable if the surface temperature is reduced and/or the stirring speed is increased after the test surface has undergone a significant amount of fouling, i.e. the fouling resistance has increased to a significant level. The fouling rate data for both positive and negative fouling rates can then be utilized to identify the fouling threshold conditions relatively quickly.
Modification of the geometry of the probe surface with wire attachment or helix threads shows a mitigating effect on crude oil and crystallization fouling, which can be interpreted by intensified turbulence as revealed by CFD simulation.
2. CFD research results on heat transfer enhancement and fouling mitigation
With the help of CFD simulation, the concept of equivalent velocity/Reynolds number is developed such that a fouling model developed for bare round tubes can be extended for use with more complex geometries.
Fouling threshold conditions, predicted by the fouling model with the help of CFD simulation, may provide a guide to avoid fouling or at least to minimise the impact of fouling by operating a heat exchanger under non-fouling conditions.
The proposed method with the help of CFD simulation offers a practical solution for estimation of the average heat transfer coefficient and wall shear stress for tubes fitted with hiTRAN inserts, revealing a significantly enhancement of heat transfer by the inserts, and the influence of the density of inserts on the heat transfer coefficient.
The induction model is valuable to predict the effects of surface temperature and velocity on the length of the induction period.
3. Shell-and-tube exchanger heat transfer enhancement know-how
Shell-and-tube exchanger heat transfer enhancement know-how has been systematised. The information on heat transfer and pressure loss inside tubes fitted with heat transfer performance-enhancing technology was collected. Main types of heat transfer enhancement - the twisted tape, static mixer, helically-coiled wire, core tube and the wire matrix insert - were analysed. It has been shown that the former two insert types are best suited to the laminar flow regime, with helically-coiled wires best suited to turbulent flow, and wire matrix inserts apparently suited well to the transition-turbulent flow regimes, but with proven applications in laminar flow. For the majority of the inserts correlations were presented. The use of a Performance Index for comparison of the thermo hydraulic performance of different inserts was considered. It was demonstrated how using coefficients in equations enable to rapidly determine the heat transfer area reduction that may result from any allowable pressure drop for a certain insert geometry. The influence of the laminar boundary layer, which is considered to be a major inhibitor to heat transfer, was studied, and the removal of which is recognised to be a significant factor in the success of enhancement devices. Optimisation work was described that has demonstrated how heat transfer performance over a flat plate varies with both the distance downstream of a wire protrusion of known thickness, as well as the thickness of the wire in relation to the laminar boundary layer.
4. Mathematical models and the software implementation of tube- and shell side heat transfer enhancement
Tube-side heat transfer enhancement:
The main findings concern the heat transfer and pressure drop data that was obtained from the test rig for a wide range of tube sizes and insert geometries. The empirical correlations derived from this data represent a significant progression in the knowledge of the performance of hiTRAN® inserts, covering almost all of the tube and insert geometries for which the company have been required to give thermal performance guarantees.
The study also presented some qualitative findings in terms of measurement of the pressure drop characteristics of a core wire. Although the function of this study was not to provide a theoretical basis to the notion of a hydraulic core wire diameter, its results may be used to separate the contributors to pressure drop in determining a semi-empirical model.
Also proposed were a number of qualitative studies, aiming to optimise the performance of hiTRAN® inserts, in terms of its geometrical parameters. The loop inclination angle (or, analogously, the coil diameter) was optimised for the most commonly used insert wire combinations inside the two most common tube sizes. This study made a useful contribution to the company’s existing knowledge of optimum coil diameter, and may be effectively used as a basis for further investigations into optimum coil diameter for other tube diameters. Optimisation of the number of turns applied to the core wire during the fabrication of an insert was carried out. This will allow the company to modify their manufacturing procedures The analysis provided on wall fit in this chapter provides a useful basis for further experiments on the quantitative determination of the effect of wall fit.
Internal fins:
Simulations were carried out to test the performance of micro-fins for different heat exchanger configurations. It was found that the overall level of enhancement of the heat exchanger was sensitive to all the studied geometric parameters: fin height and number of fins.
The study of the performance was carried out for different flow conditions within the laminar turbulent region. Based on the obtained results it was possible to conclude flow conditions under which micro-fins are not beneficial and under which conditions they are able to provide a medium-high level of enhancement of the overall heat transfer of a heat exchanger, affecting not only the tube-side heat transfer coefficient, but the overall heat transfer area.
Shell-side enhancement: Shell-side enhancement is achieved when using a non-continuous helical baffle and is more effective when the helix angle is smaller, hence, smaller helical pitch for the same diameter. However, the choice of helix angle should not allow the helical pitch/baffle spacing to drop below the width of the existing segmental ones as this will increase pressure drop levels exponentially. Moreover, higher viscosity fluids are preferred for enhancement as larger heat transfer enhancements would be achieved with a mild increase in pressure drop. In addition, it has been observed that, the pressure drop trend becomes milder at larger helical angles.
Software:
The server application was developed, the HEX Network solver software, which provides information concerning the Geometry, process and property data for each exchanger. With this information the developed dll is able to calculate the corresponding heat transfer and pressure drop results.
5. Know-how on basic configuration framework for plastic heat exchanger units
Basic design parameters of the current Makatec heat exchanger (HEX) model were analysed. The delivered design parameters represent the background for further investigations. The available HEX is presently not configured for the use with sulphuric or hydrochloric acid.
The change to polymer materials which may be exposed to sulphuric or hydrochloric acid offers the company an opportunity to take possession of a new field of application for the HEX.
A promising way towards optimisation of HEX performance is to reduce pressure drop and enhance the volume flow at the same time. This can be achieved by choosing an optimal spacer configuration inside the channels.
6. CFD models and simulation results for plastic spiral heat exchanger
The pressure drop within plastic heat exchanger grids was experimentally investigated and a CFD model describing the fluid dynamics in the spiral wound heat exchanger was developed and implemented. This model was validated using the experimental pressure drop data of Makatec. A satisfactory agreement between simulated and measured values was found.
Using this model, the spacer geometry was varied to identify its impact on the pressure drop characteristics. In particular, the spacer angle α variation and the size of the channels were tested.
7. Optimised results of the geometry and operating conditions for plastic heat exchanger units
- Pressure drop within plastic heat exchanger grids was experimentally investigated.
- A CFD model was developed describing the fluid dynamics in the spiral wound heat exchanger
- The spacer geometry was analysed and its impact on pressure drop characteristics established
- The investigations clearly show that the pressure drop reduction can be achieved by enlargement of the channels within the spacer grid, for instance, applying double layers of spacer grids or spacer grids with larger spacer diameters or bigger distances between the spacer filaments.
- Enhanced heat transfer can be achieved by induced turbulent flow pattern, but with a significantly increased pressure drop characteristics.
8. Design methodology for new heat exchanger networks using P-graph and the ABB (Accelerated Branch-and-Bound) optimisation algorithm - know-how
A novel approach to the design of new heat exchanger networks using P-graph and the ABB (Accelerated Branch-and-Bound) optimisation algorithm was developed. It considers HEN synthesis through the development of generic superstructures that incorporate all the types of the previously investigated heat exchangers, while it will accounts for a generic HEN representation to facilitate HEN interconnectivity. The approach was tested for an industrial case study and showed agreement with experimental data.
9. Retrofit procedure for heat exchanger networks prone to fouling deposition - know-how
A novel optimization method was developed to improve heat recovery in heat exchanger networks (HENs) with intensified heat transfer, and simultaneously considering fouling effects In order to solve large scale HEN retrofit problems efficiently, a new iterative MILP-based method has been proposed. The proposed design approach is able to give realistic and practical solutions for the debottlenecking of HEN as detailed intensified techniques are systematically applied. This leads substantial capital saving as no structural modification in heat recovery system configuration is considered.
To reduce energy consumption of the whole HEN, the retrofit includes the following aggregate steps:
Step 1: Optimize the whole HEN to reduce energy consumption (SA design method).
Step 2: Identify suitable exchangers for retrofit based on the optimal results obtained in Step 1.
Step 3: Identify retrofit strategies (intensifications, new exchangers, or both) in the selected exchangers.
Step 4: Consider detailed performances (heat transfer coefficients and pressure drops) of the selected exchangers.
Step 5: Select suitable intensification techniques (subject to maximum pressure drop restrictions, and required enhanced heat transfer coefficients) on the enhanced exchangers.
10. Software tool for screening and analysis design and retrofit HEN options taking into account the intensified heat exchanger parameters
Based on the integrated methodology described above, a software tool for HEN design and retrofit taking into account heat transfer enhancement technologies and fouling has been developed. A manual and training materials have also been developed and training provided to SME Partners.
11. Know-how of application of spiral plastic heat exchanger for cooling of acids
The investigations clearly show that the pressure drop reduction can be achieved by enlargement of the channels within the spacer grid, for instance, applying double layers of spacer grids or spacer grids with large spacer diameters or bigger distances between the spacer filaments.
Another way to geometry optimisation of the spiral wound heat exchangers is to enhance turbulence and hence heat transfer. In this regard, a grid geometry with interwoven spacers was investigated. The results showed indeed a turbulent flow pattern, but with a significantly increased pressure drop characteristics. It is thus necessary to investigate temperature fields and heat transfer parameters in all studied geometries and compare them. This work will be done in the near future. Further investigations are also going to be performed with regard to new materials which are appropriate for use in sulphuric or hydrochloric acid applications. The change to polymer materials which may be exposed to sulphuric or hydrochloric acid offers an opportunity to open a new field of application for the spiral wound heat exchanger.
12. Know-how of application of the toolbox developed in chemical/petrochemical industry
The demonstration case study was carried out on an existing preheat train for a crude oil distillation column in a refinery plant. The network structure includes 31 heat exchangers and 14 processing streams (3 cold streams and 11 hot streams). The retrofit objective was to reduce the hot utility (HU) consumption, namely, to reduce the heat duty of particular heat exchangers (target exchangers). As a result of application of the methodology and the software developed, the preheat train total utility consumption has reduced by ca 12%, total network operating cost has reduced by ca 4%, retrofit annual profit amounted $570k and CO2 emissions have reduced by 10% with negligible retrofit cost of $54k (the inserts and labour)
13. Know-how of heat transfer intensification for water and energy minimisation
The methodology developed provides significant fuel and hot utility savings which in turn mean hot and cold utility water consumption reduction. For the preheat train case study, the hot utility consumption was reduced by 15% utility consumption. For the crude oil distillation unit with plate frame heat exchangers the hot and cold utility consumption savings reached 10%.
14. Know-how of application of the toolbox developed in food industry
Energy studies have been carried out at three plants of a food company. The biogas utilisation plant has been identified as the most interesting and promising of the three case studies. In that plant, a full HEN retrofit analysis has been performed showing a serious potential for improving both the energy and the economic efficiency of the plant.
- A ca 70% increase in the profit on operational basis has been identified for the biogas utilisation plant, equivalent to 23 k$/y savings from decreased utility cost and increased steam sale revenues.
- The latter can be achieved by installing heat transfer enhancement devices costing ca $11k
- As a result the payback period of the investment is very attractive amounting to ~5 ½ months
The above findings have been also double-checked by performing a sensitivity study, also providing the company with an investment decision tool.
They have been further consulted and have indicated that this is a very promising retrofit suggestion, worth of considering for an investment decision.
Those case studies demonstrated the potential of the developed software tool and the methodology of INHEAT project for implementation by the SMS.
This methodology has been appreciated by all SMS involved in the project and will be providing them a considerable support for their future research and development activities.
15. Know-how of application of the plate exchangers using the software tool in chemical/petrochemical industry
Plate frame heat exchangers are still not widely used in refineries. However, the exchangers that manufactures offer at the market these days have already proved their potential benefits. The feasibility of application of plate frame heat exchangers for atmospheric crude oil unit retrofit was studied using the methodology and the software developed. As a result, the total utility cost has reduced by ca 16%, capital cost by 20%, total network cost by 14%.
Potential Impact:
The objective of the current project was to significantly increase energy efficiency of heat exchangers and their networks throughout different sectors of the process industries by developing methodologies to select and rigorously engineer the appropriate type of enhancement technology applied at a practical level, superior to existing systems in both capital cost and performance. Given that the new heat enhancement systems installed using the proposed methodology have a remarkably lower capital and operating costs it should improve the competitiveness of European end-users especially within the chemical, petrochemical, refinery, food and pulp and paper sectors. Positive impact can be identified for the consortium and industrial companies (SMEs in particular), end-users, broader Community economic and societal development.
Enhanced heat exchanger networks market
Various recent studies show that the world wide shell and tube heat exchanger market is set to grow from just under $1.9bn per year during 2005 ($0.5bn for Europe) to over $3.4bn ($0.65bn for Europe) by 2012, with Middle East and Asia markets offering the greatest growth potential with Europe and the Americas also offering attractive prospects. While the Middle East and Asia Pacific markets are expected to dominate the new build refinery sector, around 67% of the world market for shell and tube heat exchangers will continue to derive from brownfield, retrofit and revamp projects. For Europe, this is expected to grow even higher to 77% of the available market and it is this which offers the most prospects for the deployment of the innovative heat transfer solutions which the current project generated. It will be in this sector where we offer the biggest potential benefits in terms of energy consumption and CO2 emissions derived from the replacement of older, inefficient units with state-of-the-art technologies. While it is certainly already a substantial potential market for companies such as Cal Gavin and EMBAFFLE BV and, the further process intensification and heat transfer performance enhancement synergies that are expected from the combination of these and other complementary technologies including finned and profiled tubes will undoubtedly lead to even faster uptake by the market as the benefits from this work become more widely disseminated. We estimate that successful outcome of the INTHEAT could improve the potential year on year growth patterns of these and associated companies working in this area by 15-20% Compound Annual Growth Rate (CAGR) over the five year period compared with where the respective companies would be without this work being carried out. By far and away the greatest benefit will come from the application of these new process intensification/integration technologies in the reduction of energy consumption and CO2 emissions as a result of the very significant improvements in operating efficiencies and working practices from across new and existing plants.
Expected impact
The project delivers a comprehensive methodology for developing new and improving existing heat exchanger designs to significantly enhance their energy and environmental performance. The direct impact is the considerably improved cost effectiveness and increased competitiveness in the world market. The following impact contexts can be distinguished:
• General profit for the industry
• Positive impact on the project partners business and research performance
Positive impact on the industry
The expected impacts on industry are increased energy and cost efficiency, reduced environmental impact and improved availability of the energy saving measures. They will be both positive effect on the Small-to-Medium Enterprises and that on the large-scale industry. The improvement of the energy efficiency has been already registered in the range from 12-16% in larger companies in refining and petrochemical sectors and up to 40% and more for smaller-scale enterprises in eg food sector. The reason for this is that in most cases, the European heavy industry has already energy efficiency improvement measures. These measures have been made possible by the larger sites/space and capital availability. In smaller companies, energy recovery measures have been still considered too costly due to the smaller available budgets and have not been a given a clear go ahead. The potential savings in energy costs and carbon footprints are of similar magnitude. The decreased energy demands will also enable SMEs to consider small-scale local energy resources, including renewable ones, which will further limit the net rate of CO2 emissions.
Another important impact in this regard is benefits for end-users if the developed technologies from the current project are implemented. The refining industry is taken as an example. The huge costs currently associated with fouling in heat exchangers can be categorised as follows:
• Energy costs and environmental impact. In refining this corresponds to the additional fuel required for the furnace due to the reduced heat recovery in the preheat train as exchangers foul. Energy losses due to increased pressure drop (pumping power) may also be significant. The use of more fuel leads to additional production of CO2 with the associated environmental impact. Total amount of CO2 generated due to fouling is approximated 2.5% of the total anthropogenic CO2 emissions, and this crude oil fouling accounts for about 10% of total CO2 carbon footprint of refinery industries. Another environmental impact is the discharge of chemical agents used for fouling inhibition and cleaning.
• Production loss during shutdowns due to fouling. For instance, If a crude oil pre-heat train is furnace-limited, a typical 10% loss of production due to taking a heat exchanger out of service in a 100 000 US barrel/day plant would cost $20 000 US per day (assuming $2 per US barrel of marginal lost production). After shutdown, there is an additional cost due to out-of-specification production after production is restarted. The methodology developed reduces the shutdowns caused by fouling.
• Capital expenditure. This includes excess surface area, costs for stronger foundations, provisions for extra space, increased transport and installation costs, costs of anti-fouling equipment, costs of installation of on-line cleaning devices and treatment plants, increased cost of disposal of the (larger) replaced bundles and, finally, the (larger) heat exchangers.
• Maintenance costs. This includes staff and other costs for removing fouling deposits and the cost of chemicals or other operating costs of anti-fouling devices. There are also economic and environmental penalties associated with disposal of cleaning chemicals after cleaning. What has been shown, in detail, is a typical application of tube-side enhancement from a current live refining project. The results show the preheat train total utility consumption reduction by ca 12%, total network operating cost reduction by ca 4%, retrofit annual profit of $570k and CO2 emissions reduction by 10% with negligible retrofit cost of $54k (the inserts for exchangers to be enhanced and labour)
Developing new concepts for radically improving energy and capital efficiency
This project will have a significant impact in terms of energy and capital efficiency improvement by proposing new concepts in the design of heat exchangers. The development of heat exchangers using polymer materials is one such case. As a result of the project, the efficiency of heat recovery systems is expected to increase. They also cost fundamentally lower than the shell-and-tube exchangers, which makes energy saving a much more affordable option. This is expected to boost the interest of industry and especially SMEs to energy saving projects, involving reduced fouling and the discussed advanced heat exchangers.
New concepts were also developed in addressing the effects of fouling in heat exchangers. The use of CFD methods offers a rigorous representation and in-depth understanding of the underlying fouling causes and result in methods of predicting and designing heat exchangers of limited susceptibility to fouling. Fouling is also addressed in the design of heat exchange networks by appropriately manipulating HEN design and control variables that lead to prevention of fouling. Research in this area resulted in novel methods that enable the quantification of fouling effects in both individual heat exchanger equipment as well as entire heat exchanger networks. Industrial heat exchanger equipment developers and users will be able to capitalize on this work to eradicate fouling from their processes.
The databases on heat exchangers optimal duty and process streams parameters and heat transfer enhancements for wide variety of industries will stipulate the development and manufacturing of new more efficient and competitive constructions by different producing companies, even the smaller ones. This will lead to increase of competition in the area of energy efficient heat transfer equipment manufacturing and marketing with consequent decrease in prices. In turn such situation will stipulate the acceptance of such equipment by process industries and engineering companies and will contribute to long term effects of energy saving and CO2 emissions reduction according to EC targets for year 2050.
Effect on the project partners
The multidisciplinary team of the project consortium has considerably benefitted in terms of expertise and knowledge exchange from the project. The industrial partners were able to increase their energy-saving and technology development efforts, to extend their networks, better exploit the research results and acquire technological know-how, bridging the gap between research and practice. This strengthened the academic partners’ research and innovation capacity and their own contribution to the development of new technology-based products.
The optimal combination of science and private initiative, the science being the source of knowledge, and the private initiative that of technological, economic and managerial experience has been useful for both sides: it promoted penetration of the scientific accomplishments into the business and inspired the advancement of new inter-disciplinary knowledge in the scientific community.
Benefits for Industrial SME Partners
CALGAVIN expects a 1.5 times increase in its turnover from increased sales of improved and new type heat exchanger technologies as a result of the project. CALGAVIN, EMBAFFLE, OIKOS and PIL will be able to provide engineering consultancy to the processing industry in Europe and world-wide.
While considering benefits to industrial SME Partners, it is necessary to account for several important factors:
• Many of the European enterprises are in need to significantly improve their direct environmental performance via decrease of CO2 emissions. Enterprises are also pushed to continually reduce their consumption of fossil-fuel-derived energy dictated by the climate change regulations.
• Given the strong competition on the chemicals market, they also look for every measure which will cut down their bills and reducing energy by better energy recovery is always an excellent opportunity, especially in the view of crude oil prices rising to US$ 130/bbl and higher.
• A large number of new start-ups and chemical site re-openings take place in Central and Eastern Europe and most of these plants are in a great need of new technologies, especially in terms carbon emissions and energy recovery.
• Consequently, only in Europe alone there is a market for heat transfer engineering and energy recovery services amounting to at about 2-5 billion EUR per year.
Benefits for Research Partners
The RTD performers benefitted from the collaboration throughout the project and after. One important impact was strengthening the links between the academic centres via the establishment and development of a common methodological and software platform for industrial innovation. The synergy between the expertise in targeting-based Process Integration (UNIMAN), combinatorial network optimisation research (UNIPAN), computational fluid dynamics (UNIPAD), and fouling experiment and analysis (UNIBATH) has produced improved system designs and brought about wider horizons of all RTD performers involved. Concerted dissemination activities meant that along with the uptake by the industry, research institutions primarily in Europe have been aware of the Project and its activities and a wide network of business relations in the field has been established.
Benefits for potential end-users
Significantly reduced utility consumption is the major benefit for the end users. Improved heat transfer and energy integration, with increased heat recovery of about 15-20% in particular translate into up to 20% reduction in their overall operation costs. The SME partners are expected to benefit through increase of their engineering, consultancy and manufacturing business activities in the ballpark of 1.3 – 2+ of their incomes after the end of the project. This estimate is convincingly supported by a publicly available report about a production site in the United States – the 3M Hutchinson production site, where from 7 MM$/y initial energy expenses, only the applied energy recovery from the RTO units brings savings of approximately 0.7 MM$/y. This is 10% cost reduction only from the heat integration. Given the contemporary globalised market conditions such a cost reduction could result in market share increases comparable with the SMEs current turnovers. Basically, if the cost efficiency improvement potential is implemented, the only factor limiting the SME partners’ turnover increase would be mainly the availability of funds/credits and the enterprises’ management capabilities.
Longer term impacts on the consortium
The SME partners will derive their benefits from the outputs of the project primarily as vendor of the finished enhanced heat transfer equipment and/or as providers of specialised engineering design solutions based on the methodology developed and through expansion of their consultancy activities. There will be additional benefits shared within the partnership in form of a transnational network that will help penetrating markets across the EU and globally. The specific benefits, apart from economical benefits, for each partner are briefly summarised below: The calculated jobs gained by implementing INTHEAT will be spread between the consortium members, sub-contractors and suppliers, with the majority going to CALGAVIN, EMBAFFLE, PIL and OIKOS, which can boost production to follow projected sales. In total, we expect to have created 25 new jobs throughout the SME consortium by the end of year 5 post-project based on assumptions of current turnover and labour intensity. In addition to this, at least an equal number of jobs are likely to be created with third party sub-suppliers. In conclusion, INTHEAT has been economically justified for all participating industrial partners, all of which gaining payback of their initial investment within a reasonable time horizon.
Time-to-market
Before the consortium can enter the market, it initiated knowledge protection procedures. Successful outputs will help to attract investors for the upscaling of production, alongside the demand effects to be expected from a successful demonstration by end-users.
On the supply side, once protection procedures for critical IPR have been completed, the consortium will begin planning of capacity and possible expansions. Production is expected to start incrementally, the consortium being capable of supplying systems themselves for at least the first 3 years post-project according to the market analysis stipulated.
Benefits to the EU and political/societal aspects
In addition to the benefits for process industry and the consortium, we also investigate the impact at the third and final level, i.e. the positive societal effects of the project in a number of areas, also supporting European policies. The main rationale and opportunity is to produce a novel enhanced heat exchanger design and retrofit methodology, which is much beyond the state-of-the-art in overcoming current market and technical barriers.Itr provides significant advantages in terms of both performance and economics to end-users, and at the same time contributes significantly to meeting EU policy objectives, especially within Energy/CO2 Environment emissions field.
Build-up of dirt deposits, or fouling, on the metal surfaces of petrochemical plant heat exchangers is a major economic and environmental problem worldwide. According to IHS estimates have been made of fouling costs due primarily to wasted energy through excess fuel burn that are as high as 0.25 per cent of the gross national product (GNP) of the industrialised countries. With oil prices at record highs, the payback from fouling reduction by increased throughput and less wasted fuel increases year on year. Many millions of tonnes of carbon emissions are the result of this inefficiency. Costs associated specifically with crude oil fouling in the pre-heat trains of oil refineries worldwide are estimated to be of the order of $4.5bn (http://uk.ihs.com/news/overcoming-effect-oilfouling.htm). Following these estimates, the EU losses from fouling constitute 42,075 million 2007 USD. The project will provide solutions which will enable to reduce those losses by 25- 35 %. For the countries where participating Partners are planning to primarily exploit the results of the project the loss reductions are estimated as follows (Table 1). Successful completion of INTHEAT goals will be considerable contribution to the implementation of Directive on eco-design requirements for end-use energy-using products (2005/32/EC, O.J. L 191of 22.7.2005) and the Directive on energy end-use efficiency and energy savings (2006/32/EC, O.J. L 114 of 27.4.2006).
Table 1. Estimated fouling caused loss reductions in some countries:
Country - Fouling caused loss reductions, MM USD 2007
Czech Republic - 131
Germany - 2,492
Greece - 236
Hungary - 104
Italy - 1,578
Slovakia - 56
Spain - 1,079
The Netherlands - 577
UK - 2,079
Ukraine - 1,005
List of Websites:
www.intheat.eu
