Development and testing of tube type wet ESP for the removal of particulate matter and tar from producer gas

•A wet ESP was developed and tested for the removal of particulate matters and tar.•Wire and tube radius were determined using simulation of electrical characteristics.•Maximum removal efficiencies of particulate and tar were 83% and 62%, respectively.•Cleaned producer gas purity meets Indian standard for use with gas engines.

This paper reports the development and testing of a state-of-the-art tube type wet electro-static precipitator (ESP) for cleaning producer gas generated through the process of biomass gasification. A wet ESP facilitates the removal of fine particulate matter (less than 1 micron) and tar with the added advantage of low internal power consumption. A tube type wet ESP was designed from first principles and simulations were carried out to prove its performance. Later on a full-fledged wet ESP was designed to process 100 Nm3/hr of gas, and was tested with an existing open top down draft biomass gasification system. Maximum particulate matter removal efficiency of 83% and tar removal efficiency of 62% was achieved. The results were encouraging to the tune that the particulate matter and tar levels were found below the permissible limits (50 mg/Nm3) for naturally aspirated reciprocating engines and thus the proof of concept was established. Nevertheless, the performance fell short of the permissible limits for turbo-charged reciprocating engines. The cause of the same has been identified and further development work is in progress.