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Design for Resource and Energy efficiency in cerAMic kilns

Periodic Reporting for period 2 - DREAM (Design for Resource and Energy efficiency in cerAMic kilns)

Reporting period: 2018-04-01 to 2019-09-30

The EU ceramics industry is a key contributor to export, value added and jobs, representing an annual production value of around €30 billion (2018), delivered by 17,000 enterprises directly employing over 240.000 people. Ceramic processing is highly demanding in terms of energy: the production of one ton of ceramic tiles required 6GJ (1.67 MWh) of energy, and the ceramic industry has the highest number of installations in EU Emission Trading System, mainly associated with the use of energy in the kiln and spray dryer.
Within the ceramic manufacturing process, firing accounts for 55% of all thermal energy used in tile manufacture . Average thermal energy consumption in ceramic tile manufacture is estimated to be 1,28 kWh/kg fired tile, relative to the lower heating value (LHV) of natural gas. The energy required in the process is obtained by combustion of natural gas, which is a fossil fuel. Natural gas combustion gives rise to air emissions of carbon dioxide (CO2), a greenhouse gas, the emissions of which are internationally subject to control and capture measures.
In order to encourage the evolution of ceramic kilns towards a more sustainable technological paradygm, the DREAM project aims to design, develop and demonstrate a radically improved architecture for ceramic industrial furnaces, characterised by optimised energy consumption, reduced emissions, and lower operating costs compared to currently available technological solutions. This will be obtained by substantially enhancing specific furnace parts (control system, refractories, emissions abatement system) and by adding new modules and sub-systems (CHP unit, heat pipes) to the current furnace architecture.
The DREAM Specific Objectives are:
Biofuel fed CHP integration in firing stage (WP1). In order to optimise the firing process energy consumption, DREAM integrates state-of-the art technological solutions which have never been applied to the ceramics industry, and which will represent a significant upgrade to the current practice.
Advanced simulation tools equipped kiln control system (WP2). DREAM aimed to endow end users with accurate and optimised process control tools, by integrating within the kiln control system an ad-hoc developed thermal-fluid dynamic model.
Waste heat recovery through heat pipes (WP3). DREAM designs a solution for conveying waste heat from the cooling stage of the kiln to the drying stage of the ceramic manufacturing line.
Innovative refractory solutions and new materials for insulation (WP4). Through DREAM, the consortium developed innovative refractory materials and retrofitting solutions (including foam ceramics, opacifiers and emissivity coatings), aimed to reduce the heat transfer within refractory materials and to optimise the heat transfer between the kiln and the materials.
Emissions monitoring and abatement techniques optimisation (WP5). DREAM systematically investigated and optimised currently employed emissions abatement techniques in the ceramics industry, based on the combination of Best Available Techniques with a specifically designed absorbent for filters.
DREAM develops and demonstrates technologies enabling a significant advancement in the sustainability of ceramics processes, implementing 5 synergic lines of research and 3 industrial demonstrators, which are acting as technological showcases for market deployment.
The achieved results, classified by WP are listed below:
WP1 - The CHP unit is installed besides an industrial plant for ceramic tiles production where a new generation kiln is operational. All the required functional tests have already been carried out, both with natural gas and biomethane as well. WP Subjected to an amendment.
WP2 - UNIMORE has built up the 0D/1D model to represent the physical phenomena involved in the processes in the different kiln sections, namely fluid dynamics of air streams and burnt gases, heat exchange among the different kiln components, thermal behaviour of products (tiles) all over the kiln length. A new software to identify and manage production gaps along the production line has been developed by Synesis and tested besides MIRAGE facilities. The ”sleep mode” algorithm has been developed and tested.
WP3 - Due to safety concerns the heat pipes structure was positioned out of the kiln to work as heat exchanger to the drier post press. The HPAP has been positioned, connected and tested: full report available to the relative WP description: This Wp has been subject to an amendment.
WP4 - Studies and manufacturing of a new insulating brick and a new lining pattern have been carried out within Rath facilities and the resulting output tested in the lab kiln at Sacmi facilities in Imola. All the measurements and tests have been carried out and concluded.
WP5 - All the programmed tests have been performed and data collected to identify the optimal working conditions of the different filters in relation to the pollutants to abate. The reduction in pollutants emission of 30% has been reached and overcome for all the pollutants indicated in the BREF guidelines.
WP6 - In the Demonstration phase prototypes developed within WP1-5 have been integrated in a set of three industrial demonstrators, in order to test the expected performance improvements against real-life working conditions.
WP7 - Communication strategy aimed at communicating DREAM’s results to promote their impact and benefits to the whole society, addressing a multiple audience in terms of knowledge and interests.
To be successful in designing the exploitation plan of DREAM results, the consortium started with the identification and characterization of the exploitable results. Indeed, not all of what has been achieved throughout course of the project was likely to have an exploitation route. Exploitable results are only those having a potential scientific, economic and social significance. A systematic approach to the characterization of the exploitable results was followed: it not only allowed to classify the exploitable results into different categories, but also provided for reference points and benchmarks related to the innovation levels and technology readiness.
WP8 - Project management had the aim to monitor and keep the project on track in terms of time, technical results and resources, ensuring efficient management and coordination at the administrative, financial and technical level.
Several innovations will be introduced through DREAM, namely:
- A new CHP concept never applied in ceramics firing
- A breakthrough simulation approach to improve the kilns design process
- A novel heat recovery concept for ceramic firing, using heat pipes
- A bespoke coating and insulating fire brick optimised for operational conditions in ceramic firing
- An emission abatement system compliant with emerging pollutants and regulations
Through the introduction of ceramic kilns with lower energy consumption, the DREAM project will make the EU ceramic industry more sustainable both environmentally and economically, and will help to increase competitiveness in the European process industry. Furthermore, the project will help to maintain and even increase the employment in this important industrial sector despite the uncertainties regarding the international situation, and at the same time it will reinforce the competitiveness of the value chain, mainly represented by the high-skilled European ceramic machinery industry.