High Temperature. Raw Material In The Gasification Gas, Hydrogen Sulfide Removal

Biomass is attracting more and more attention as a kind of renewable energy. Biomass gasification is one of the main technologies of biomass utilization. There is a minim quantity of hydrogen sulfide in the biomass producer gas. It will not only pollute environment, but also poison the catalysts of removal tar and removal ammonia. Therefore, the hydrogen sulfide, which is the pollution content in the biomass producer gas, must be removed before using the biomass producer gas. This dissertation focuses on the performance of sorbents removing hydrogen sulfide at high temperature.Three kinds of sorbents prepared in the research. They were dolomite sorbent, zinc titanate sorbent and Ni/Zinc titanate sorbent. Dolomite was used to produce half-calcined dolomite and calcined dolomite sorbent by calcining the raw dolomite at 800℃ and 950℃ respectively. Using bentonite as agglomerant and NaCMC as pore-enhancer, zinc titanate desulfurizer was produced by mixing zinc oxide and titanium dioxide through mechanical dry mixing method according to a certain proportion. Ni/Zinc titanate sorbent was made by calcining Ni/Zinc titanate sorbent for an hour at 650℃ after it impregnated with certain amount of nickel nitrate. Before desulfurizing reaction, the prepared dolomite sorbent and zinc titanate sorbent were heated to reaction temperature under the protection of N₂. But Ni/Zinc titanate sorbent needed to be heated to 650℃ under the protection of N₂, and then reduce by H₂ completely for 2.5h before desulfurizing reaction. The H₂S content of the outlet gases were investigated online by Varian CP-3800 GC. Three characterization methods of the lab samples were as followings: X-ray analysis, specific surface area and pore analysis, and thermal analysis.The experiment results show that both dolomite and zinc titanate can be used as sorbents for desulfurization during the experiment of hydrogen sulfide removal reaction at high- temperature. The desulfurization capacity of half-calcined dolomite...