AD-BES
AD-BES unit
Introduction
In general, the Bioelectrochemical Systems with Anaerobic DigestionAD-BES enable effective wastewater treatment. An anaerobic digester combined with a bio-electrochemical system (1 m3 volume) produces biomethane with a purity of up to 95% owing to microbial conversion of the organic matter content of wastewater.
The AD-BES system proposed in the ROBINSON project's case is built by Hysytech.
AD-BES unit
Technical description and Technology Flowchart
Figure 1 AD-BES Technology flowchart
An anaerobic digester in combination with a bio-electrochemical system (1 m3 volume) produces biomethane – up to a purity of 95% – due to microbial conversion of organic matter content of wastewater. The BES unit is supplied with electricity at a voltage near 1 V, in order to upgrade the AD unit in terms of process kinetics and CH4 content of produced biogas. The technology has several advantages, such as high process efficiency under mild operation conditions, high flexibility regarding power fluctuation and plant size as well as the opportunity for seasonal energy storage in the form of biomethane.
Technology requirements and operating conditions
Some characteristics foreseen for AD-BES units are presented below.
Operational parameters of the AD-BES pilot plant
|
Parameter |
Value |
|
Biogas production rate |
0.12 – 0.22 Nm3/day |
|
Delivery temperature |
37 oC |
|
Delivery pressure |
0.02 barg |
|
Composition of biogas (range values) |
CH4 65 mol% (min value) H2 0 mol% H2O 6 mol% CO2 29 mol% H2S 500 ppm VOC 100 ppm |
|
Electrical power need (AC) |
3.5 kW |
|
Wastewater demand |
100 L/day (min value) ORL: 0.35 – 0.7 kgCOD/m3/d (min value) 5 oC - 40 oC 2 – 8 barg |
|
Compressed air |
1 Nm3/hr 6 – 8 barg |
|
Flow rate of drain |
Min 3 m3/hr |
|
Internet connection (min requirement) |
1 Mbps for upload 6 Mbps for download |