Use of fabric filters for syngas dry filtration in small-scale gasification power systems

This work focused on the assessment of the wood gas filtrating performances of fabric filter bags applied to a small-scale commercial gasification power plant by All Power Labs. As known, the raw producer gas contains pollutants such as tars and particulate matter that need to be removed in order to avoid the premature failure of the mechanical parts of the facility and of the internal combustion engine. PTFE-coated and felt bags were tested to assess their response to the tars and water vapors condensation, in terms of pressure drop. The results shown on one hand the tendency of felt bags to be more sensible to condensation phenomena and on the other hand the drawback of PTFE bags to generate higher pressure drop since the beginning. The possibility of pre-coating the felt bags with fine biochar generated from the gasification facility was then tested. Tars and soot gravimetric analyses conducted on wood gas samples shown the ineffectiveness of pre-coating using char and the coherent tendency of felt bags to increase the filtration performances over time.