WABICO, WAALWIJK: FROM WASTE TO BIOMETHANE, CLEAN WATER, SOLID COMPOST & LIQUEFIED CO2
HoSt has constructed a biogas plant in Waalwijk, the Netherlands, with the purpose of producing biomethane (green gas) from various waste streams like roadside grass, vegetable waste, flotation sludge’s and unpacked supermarket waste. Due to the combination of different innovative techniques, it is one of the most advanced biogas units in the world.
The solid feeding system is capable of handling difficult fuels. The installation is provided with a size reduction step to make it possible to use high amounts of grass.
In this project, a biogas upgrading unit is placed to upgrade biogas to the quality of natural gas. The capacity of the plant is 1,000 Nm³/hr ingoing biogas that is upgraded to 650 Nm³/hr biomethane. The biogas upgrading has an integrated heat recovery system, so that no gas is needed for the digester. The biomethane is injected into the national gas grid. The upgrading kit including compressor, membranes, control panel, heat recovery, odorisation and biogas analysis is placed in three containers. The three containers are located at an upgrading island besides the AD-plant.
The digestate coming out of the AD-plant will be processed to dischargeable water that will be discharged into the sewer. This is reached due to a screw press separator in combination with a decanter centrifuge and PE-injection. Deammonification is done by the DEMON® process.
CO2 RECOVERY SYSTEM
A CO2 recovery system recovers and liquefies the CO2 (carbon dioxide), that is filtered after entering the 3-stage membrane separation system. The recovery system compresses, filters and cooles the CO2 to reach the required purity and liquid state. This captured CO2, stored in storage tanks, is used in the food and beverage industry, and creates an extra source of revenue. Besides this advantage, another great advantage is that the methane slip is reduced to zero.