The Study On The Immobilized Laccase And Application Of Oil Removal In The Circulating Cooling Water System

The problem of general oil leakage has been commonly found in C hina's oil refining companies.O il leakage makes circulating water containing a large amount of petroleum hydrocarbons,which affects the normal operation of the production plant.Enzyme is a kind of green environmental protecting biological catalyst,which can degrade oil material effectively.According to the disadvantage of free laccase,such as can be easily affected by environmental conditions and its reaction system is not easy to separate,this paper uses immobilized laccase instead of the free enzyme to overcome the deficiency of the free enzyme,and studies on the immobilized laccase and oil removal effect in diesel oil leakage of the circulating water.The main contents include(1)Studied on the three methods of immobilized enzyme,such as embedding method,crosslinking method and embedding-crosslinking method,then determined the optimal immobilized conditions.(2)Optimized the process conditions of circulating cooling water with diesel.(3)Studied on the synergy of the conventional corrosion inhibitors(PASP and ATMP)and immobilized laccase.(4)Maked a filter column with the immobilized laccase compound medicament and the activated carbon,then investigated oil removal rate in the practical application.The experimental results show that laccase immobilized with crosslinking method has the best deoiling effect,it can degrade 77.2% of the diesel,and after being repeatedly used 6 times,oil removal rate can reach 44%.Fix the ATMP which corrosion inhibition is better and laccase on chitosan carrier and optimize the corrosion inhibition of the immobilized laccase,the inhibition rate increases from 16.22% to 46.89% under the same conditions.Fill the immobilized laccase and PAC into the filter column,set the flow of the pump to 0.9L/h,and the oil removal rate is 92.8% after 5 times through the filter column.The oil removal rate is 30% when equipping with an equal amount of active carbon in the filter column.So the result confirms the feasibility of the immobilized laccase of oil removal in the filter column.