Beter (dan) vergisten
At present manure digesters are designed on the basis of robust and proven technology for which it is known that the economic viability is marginal. In Beter (dan) Vergisten companies and WFBR team-up to develop new technological routes throughout the chain which will drastically improve the situation.
The innovations developed in Beter (dan) Vergisten will improve the business case of digesters to the point that they are profitably operated without subsidy. Digesters as such do not contribute in solving the phosphate problem of the agro-food sector in the Netherlands. Within the framework of the proposed project, innovative technologies are developed to economically separate phosphate from manure having the potential to close the phosphate balance.
Digesters offer an efficient method to convert manure into energy (biogas) and a residual mineral concentrate. New digesters are in planning for the manure surplus of livestock farming (East-NL greater than 1,000,000 tonnes in 2017). The design of existing and new digesters is based on robust and proven technology (Best Available Techniques), of which it is known that the economy is only marginal, even with subsidies. In Beter (dan) Vergisten new technologies are developed that improve the economy by both increasing biogas production and recovering valuable components. This will be achieved by:
- Preventing preliminary losses of fermentable solids and CH4;
- Oxidative treatment of unfermented organic matter and recycling;
- Conversion of small fatty acids into valuable biopolymers;
- Phosphate extraction from the digestate; and
- Production of ammonium sulfate from the thin fraction.
The original goal of the project is to improve the economics of fermenters. The project also has a potential contribution to the objectives of the Climate Agreement, the prevention of nitrogen emissions and the closing of the phosphate cycle:
- Increasing the gas yield and reducing biogas losses on the farm contribute to the reduction of CO2 emissions described in the Climate Agreement;
- Extraction of products (e.g. PHA (poly-hydroxy-alkanoate)) creates additional economic value that is necessary to achieve the social goals;
- New technology development for closing the phosphate, nitrogen and potassium cycle.
For each of the five steps to improve the economy of the digester, focus is on:
- Selecting the most appropriate technology;
- Evaluating the business case;
- Ensuring process and feedstock characteristics;
- Obtaining the desired intermediate products; and
- Any constraint imposed by law and regulations.