The Biobed® EGSB technology (Expanded Granular Sludge Bed) is an extremely compact, high performance anaerobic treatment process for industrial effluents using granular sludge.
To prepare the industrial effluent for anaerobic treatment, the pH-value and the temperature of the raw wastewater are regulated in a pretreatment step in a conditioning tank. The liquid will also be mixed with recycled, treated anaerobic effluent from a recirculation step to attain a homogenous body. Nutrients are added if necessary to achieve optimal growth conditions for the anaerobic biomass in the Biobed® EGSB reactor.
In the following treatment step the conditioned wastewater is pumped at a constant, continuous flow to the tall and slender Biobed® EGSB reactor. A special influent distribution system guarantees equal distribution over the entire reactor surface area. The influent then passes a dense and expanded anaerobic granular biomass bed where the biological treatment takes place converting the COD load (Chemical Oxygen Demand) present in the wastewater into biogas.
At the reactor top patented three phase settlers, which are installed internally in the reactor, separate the treated water from the produced biogas. The biomass settles back to the reactor bottom while part of the treated effluent is recycled and returned to the conditioning tank for dilution.
Biogas is collected at the top of the reactor and is piped to a biogas treatment step. Under controlled conditions it can be burned in a biogas flare or alternatively serve as a source of energy for the production site.