Converting the organic fraction of solid waste from the city of Abu Dhabi to valuable products via dark fermentation - Economic and energy assessment

- The cost and energy demand for dark fermentation using OFMSW were established.
- Dark fermentation using OFMSW can produce a carbon source for bioprocesses of about 330 USD/tCOD.
- A maximum purification cost of VFAs from dark fermentation using OFMSW was established to 15 USD/m3.
- Replacing fossil fuel based products by dark fermentation will probably lead to net energy savings.

Landfilling the organic fraction of municipal solid waste (OFMSW) leads to greenhouse gas emissions and loss of valuable resources. Sustainable and cost efficient solutions need to be developed to solve this problem. This study evaluates the feasibility of using dark fermentation (DF) to convert the OFMSW to volatile fatty acids (VFAs), fertilizer and H2. The VFAs in the DF effluent can be used directly as substrate for subsequent bioprocesses or purified from the effluent for industrial use. DF of the OFMSW in Abu Dhabi will be economically sustainable once VFA purification can be accomplished on large scale for less than 15 USD/m3effluent. With a VFA minimum selling price of 330 USD/tCOD, DF provides a competitive carbon source to sugar. Furthermore, DF is likely to use less energy than conventional processes that produce VFAs, fertilizer and H2. This makes DF of OFMSW a promising waste treatment technology and biorefinery platform.