| 摘要 |
PURPOSE:To provide the method for treating waste gas capable of preventing the air polution due to CO2, SOx and NOx generated by burning of gaseous methane and attains the pH control of a methane fermentation tank and the acceleration of the nitrification in a water treating system. CONSTITUTION:The basis of the method is that after removing hydrogen sulfide from the gaseous methane generated from the methane fermentation tank 1 by a desulfurizing apparatus 2, the hydrogen sulfide is burned by a burning device 3 and 3a, and combustion waste gas is subjected to the selective reduction of NOx while mixing with the gaseous methane under the presence of the catalyst at a denitrification catalyst reactor 4. Moreover, the treating method in which the waste gas passing through the denitrification catalyst reactor 4 is introduced to a carbon dioxide absorption apparatus 5 under supplying alkali soln. to fix the carbon dioxide as water soluble sodium carbonate is provided. Some of the fixed sodium carbonate aq. soln. is fed to a water treating system 8 to accelerate nitrification and on the other hand, the other part of the aq. soln. is returned to the methane fermentation tank 1 to be used as a pH controlling agent. |
