Study On Treatment Of Coal Pyrolysis Wastewater By Moving Biological Bed In Oxygen Limited Environment

In China,the energy content of oil and natural gas is relatively low,and the content of coal is high.The imbalance of the energy structure affects the economic and social development of my country.The coal pyrolysis industry uses coal to produce energy such as oil and natural gas.Therefore,the development of the coal pyrolysis industry is the only way for my country to alleviate energy conflicts.However,the coal pyrolysis industry has problems such as high water consumption,large amount of waste water,and large amounts of toxic substances such as ammonia nitrogen,phenols,aromatic hydrocarbons,heterocyclic compounds,etc.,and the country has put forward requirements for "zero emissions",but The "zero emission" standard has not been reached,and there are many problems in technology and economy.In this paper,oxygen limited environment mobile biological bed is used as the research object.Through aeration pump and mechanical stirring,the oxygen limited environment is realized.The influence of two kinds of fillers of powdered activated carbon and polyurethane foam on the degradation efficiency of coal pyrolysis wastewater is explored.The best dosage of powdered activated carbon and the best filling rate of polyurethane foam are determined,and the total phenol load,hydraulic retention time and dissolved oxygen concentration of the influent are optimized.Compared with the influent quinoline load and other conditions,the degradation efficiency of the two systems was compared to provide suggestions and suggestions for practical engineering application.In the intermittent flow experiment,the best dosage of PAC is 3 g / L,and the particle size of PAC is 60 mesh.Through the change of polyurethane foam filling rate,influent total phenol concentration,hydraulic retention time and water temperature,the study shows that the best filling rate of polyurethane foam is 30%,and the water temperature of 30 degrees centigrade can achieve better results.In the continuous flow experiment,the study of the influencing factors such as total phenol load,hydraulic retention time,dissolved oxygen concentration and quinoline load of the influent showed that the hydraulic retention time of the powder activated carbon mobile biological bed and the polyurethane foam mobile biological bed was 48 h When the dissolved oxygen concentration is 0.5-1.0 mg/L and the influent quinoline concentration is less than 150 mg/L,it has good degradation efficiency for coal pyrolysis wastewater.The analysis of the sludge shows that,compared with polyurethane foam,powder activated carbon has a more obvious strengthening effect on sludge properties and microbial population.Through economic analysis and comparison,compared with the traditional AO process,the operation cost of the powder activated carbon mobile biological bed process increased to 0.48 yuan / ton water,and the operation cost of the polyurethane foam mobile biological bed process increased to 0.44 yuan / ton water,and the difference between them was small.