(513g) Evaluation of a Novel Nickel-Ceramic Filter for Hot Gas Removal of Tars and Particulates from Biomass Syngas

Biomass gasification is considered one of the most promising thermochemical routes for converting biomass to energy, which involves partial oxidation of carbonaceous fuels at high temperatures to produce synthesis gas. Syngas has a variety of applicable uses including combustion for combined heat and power, generation of electricity, use as a feedstock in transportation fuels, and production of general/specialty chemicals. Downstream syngas applications require contaminants in syngas to be below certain levels in order to process effectively.

Two syngas contaminants that present major hurdles limiting biomass gasification commercialization are particulate matter and tar content. Typically, particulate matter is separated through high temperature filtration using metallic or ceramic materials. Tar formation is the most cost inducing problem whereby their condensation creates problems in processing by clogging and fouling downstream equipment. The most promising and cost-effective strategy for tar abatement is catalytic tar reforming, whereby conversion of tars into syngas improves the overall efficiency of the gasification process. By using a ceramic filter as a catalyst support, process intensification can be achieved by reforming tars and filtering particulates in a single unit.

The surface area of the ceramic filter (91 m²/g) makes it an ideal support for catalyst material and its high porosity (85%) leads to a low pressure drop and minimal internal mass transfer limitations. Nickel was effectively impregnated on the filter via incipient wetness method. Steam reforming evaluation tests using naphthalene as a tar simulant were performed at 750°C, steam to carbon ratio of 5, and a residence time of 0.07 s with an inlet naphthalene concentration of 15 g/m³. Naphthalene conversions of up to 82% were observed for 2 hours with a Nickel loading of 15 wt%, which is comparable with commercial catalysts for tar removal.