Biomass gasification producer gas cleanup

In addition to primary gases, biomass-derived producer gas contains nonnegligible concentrations of undesirable byproducts collectively known as contaminants. Syngas contaminants are composed of tar-, nitrogen-, and sulfur-based compounds and halides and other trace metals that must be minimize their negative impacts on downstream processes or to adhere to environmental regulations. The producer gas cleanup consists of all processes that are employed to reduce the concentration of contaminants in raw producer gas prior to conditioning and utilization in downstream applications. This chapter discusses primary contaminants, the impact of operating conditions on them, their mitigation and regulations governing their emissions. Additionally, best of available technology (BAT) are discussed for select contaminants.