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Use of HTC technology as an innovative reuse method for sewage sludge

Periodic Reporting for period 1 - HTSew (Use of HTC technology as an innovative reuse method for sewage sludge)

Reporting period: 2014-10-01 to 2015-03-31

Efficient municipal wastewater treatment, such as the systems currently in place in most European municipalities, produces vast amounts of sewage sludge. The latest data collected show a yearly production of 9.637 thousands of tons in the EU28 countries. The most common disposal methods for sludge are spreading on agricultural soil, composting, incineration and anaerobic digestion. Spreading on soil entails on average the lowest cost (15 €/ton), but it is not an available option in all EU28 countries, due to different legislations in force, and that the more and more regions are banning this use due to safety concerns. Incineration entails the highest costs (50-130 € /ton), but is also considered the safest disposal method and is fast growing and widely adopted. However, it presents also technical difficulties, such as the low overall efficiency of the process (sludge can contain up to 85% water, which renders the process very inefficient), the huge logistic efforts required to transport the sludge to the incineration plants, or the disposal of the ashes after the sludge has been incinerated.

In this situation, Ingelia has the objective to demonstrate and commercialize their proprietary technology for hydrothermal carbonization (HTC) to the conditions of sewage sludge (HTSew), showing clearly technical and economic advantages against the current sludge treatment methods. Ingelia aims to reduce the treatment costs for the sludge, providing an innovative technology, which is at the same time beneficial for the environment. The HTSew process turns the sewage sludge disposal from a costly and environmental unfriendly process into an income-generating activity, by reducing the treatment costs and enhancing locally the industrial sector
During phase 1 of SME-Instrument, Ingelia has already carried out tests at industrial scale (5 tons) with their in-house prototype which have shown that sewage sludge is a technically viable feedstock for HTC, and that the treatment and reuse price using HTC would be at 50 €/ton, almost a 50% reduction from the most moderate of the currently available incineration options. Based on the results of the test runs technical optimizations have been developed for HTC mono-systems for sewage sludge. Other objectives on phase 1 were to make a feasibility study that assesses in depth the existing sludge disposal markets identifying and characterizing the regions where the current market for sludge disposal is ready for the uptake of HTC, by (i) the identification of the most promising regions at the NUTS-2 or NUTS-3 level with regard to sludge production and current disposal methods; (ii) the identification of potential local distributors or commercial agents and setup of a commercialization network; (iii) the identification of the possible HTC products and commercialization strategies adapted to each region and product; (iv) the construction of a database of potential customers, end-users and competitors. Phase 1 permitted to Ingelia to construct the business plan based on HTSew, as well as to prepare the deployment strategy for achieving it.

The requested funding (Phase 2 of SME-Instrument) would be needed to implement and construct a demonstration plant for sludge treatment (15 tons/day) and run demonstration tests for interested clients in key markets, and deploy the business.
The feasibility study has comprised:
Task 1.1: Identification of the most promising regions at the NUTS-2 or NUTS-3 level with regard to sludge production and current disposal methods:
- Market analysis in these regions: Disposal fees, logistics, number of disposal agents and/or plants, price structure, competitors to HTC
- Legal framework: Disposal routes allowed and banned
- Profile of suitable clients (amount of sludge, cost of disposal, size of WWTP, supervising capacities)
- Restrictions and emission limits for sewage sludge handling, process emissions and coal combustion in different markets
- Assessment of the price trends of incineration and price elasticity of the demand
Task 1.2: Identification of potential local distributors or commercial agents and setup of a commercialization network
Task 1.3: Determination of the possible HTC products and commercialization strategies adapted to each region and product
Task 1.4: Compilation of a database of potential customers, end-users and competitors
Task 1.5: Business plan:
- Capacities of Ingelia
- Development of the growth strategy.
- Profit and loses projection
- Sensivity analysis in three different scenarios
- Cost-benefit analysis, defined as minimum of plants that need to be sold to achieve sustainable growth at Ingelia.

The outcome of HTSew project (Phase 1 of SME-Instrument) is the definition of the business plan and the deployment strategy for the creation of a new business pathway in the upgrade of sludge into new resources using HTC, which will pave the way to provide economically attractive and environmentally friendly alternatives to utilization of what nowadays is considered a difficult waste.
The main needs of the targeted end-users of HTC plants processing sludge are cost-effective and safe disposal ways for their produced sewage sludge. HTSew is offering an innovative, safe and cost-effective disposal method for sewage sludge. Beyond that, HTSew will provide a solution that is not only more economic than the ones in place, but that will reduce the operational costs for the HTSew plant operator.

A study performed in the HTSew project shows the income that could be generated by a 2-reactors plant treating up to 23.400 tons of sewage sludge yearly. Assuming a 50€/tDS tipping fee, the HTSew plant will generate benefits around 685.000€/year, that is, a 4.1 years of amortization period for the 2.8M€ of investment.

HTSew addresses a global market, and one that has a huge potential in Europe. With more than 84.000 wastewater treatment plants and 9.637 thousand tons of sludge produced each year, the implementation of HTSew will have a profound impact in the sludge disposal sector towards a higher sustainability and increased business opportunity, turning disposal plants from mere sinks of matter and energy to industrial plants processing the sludge environmental friendly and enhancing innovation in the industry sector.

The completion of HTSew in the Phase 2 will open a yet untapped market for Ingelia, with a huge potential for implementation and which will imply a business development worth millions of Euros. By achieving funding for the Phase 2 Ingelia will have the necessary resources for building a demonstration plant that will be definitive to boost the uptake of HTC by the wastewater treatment sector.
Ingelia estimates that sewage sludge sector will imply a growth and increase in value for the company estimated to triple in a period of four to five years after the project is completed, reaching a turnover of 70 Mio € in the fifth year after the project ends. It will also entail the generation of jobs, at least 80 direct and as many indirect (commercial network on site and suppliers).
Disposal methods for sewage sludge in EU-27.
Collaborating institutions of Ingelia
Ingelia's history
Deployment strategy for HTSew