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

This paper discusses the development and testing of small scale plate type wet electro-static precipitator (ESP) for cleaning of producer gas generated through the process of biomass gasification. This work is a sequel of the previous work carried out by the same authors on tube type wet ESP. As there were limitations in the design of tube type wet ESP, in terms of continuous operation, a plate type wet ESP having a short residence time charging stage followed by a long residence time precipitation stage was designed from first principles and simulations were carried out to establish its performance. Based on the results of this design study, a full-fledged wet ESP system comprising a two-stage reactor was built and integrated with an existing open top downdraft biomass gasification system. The system was subjected to rigorous testing in order to establish its performance. The outcome of testing was positive to the extent that the gas quality in terms of permissible level of particulate matter and tar was much superior to the prescribed norms for naturally aspirated engines. For turbo charged engines, the particulate matter was well within the prescribed level, and tar was marginally higher than the prescribed value.