A method for strengthening hydrophobic toluene biodegradation

Abstract

The invention discloses a method for enhancing biodegradation of hydrophobic methylbenzene, and belongs to the field of volatile organic compound treatment technologies. The method comprises the following steps: adopting bacteria obtained by performing methylbenzene gradient domestication on activated sludge from a wastewater treatment plant; preparing a bacterium suspension for later use after enlarged cultivation; adopting expanded clay aggregate as a filler for a bio-trickling filter, and laying the filler layer by layer; spraying the bacterium suspension to the expanded clay aggregate uniformly from the upper part of the bio-trickling filter; feeding high-concentration methylbenzene gas from the bottom of the bio-trickling filter for further domestication; starting the bio-trickling filter in a gas-phase domestication biofilm-culturing manner, forming biofilms, and enabling the bio-trickling filter to enter the next stable operation stage; adding rhamnolipid, a biosurfactant, to a circulating nutrient solution; spraying the circulating nutrient solution to the filler from the upper part of the bio-trickling filter to allow the rhamnolipid to distribute uniformly on the filler along with the circulating nutrient solution through a liquid distribution board; feeding waste methylbenzene gas to be treated from the bottom of the bio-trickling filter. The method has the advantages that the operation is simple, no secondary pollution is generated, and the biodegradation efficiency of hydrophobic methylbenzene, a VOC (Volatile Organic Compound), can be increased.

Description

technical field [0001] The invention mainly relates to the field of treating volatile organic compounds by using a biological trickling filtration method, in particular to a method for using a biosurfactant to strengthen the degradation of hydrophobic volatile organic compounds toluene in a biological trickling filtration reactor, and belongs to the technical field of volatile organic compounds treatment. Background technique [0002] Volatile Organic Compounds (Volatile Organic Compounds, VOCs) are a class of difficult-to-handle organic compounds including aliphatic and aromatic organic compounds. They have a large evaporation rate and are volatile at room temperature. A large amount of VOCs will be produced during the production, storage and transportation of chemical products and most of the processes involving the use of organic solvents. Daily transportation and pollutant treatment processes will also produce VOCs. VOCs are more harmful to the human body, and some subst...

AI Technical Summary

Problems solved by technology

[0004] In the traditional biological method, the mass transfer process of hydrophobic VOCs from the gas phase through the liquid film to the biofilm has a large resistance, which reduces its bioavailability and becomes the main factor limiting its capture and degradation by microorganisms.

After the water holding capacity in the medium is reduced, the thinning or disappearance of the water film on the outer surface of the biofilm reduces the resistance of the water film, increases the mass transfer rate of toluene and oxygen in the gas phase to the biophase, and then improves the oxidation of biomass in the biofilm. Degradation rate, but too low moisture will affect the activity of the biophase in the trickling filter