Experimental Research On The Preparation And Application Of Embedded Immobilized Microorganisms In Water Quality Control Of The Recirculating Aquaculture System

This dissertation chooses the embedded immobilized microorganisms as the main research object,studies the preparation of the embedded immobilized microorganisms and the removal of ammonia nitrogen,nitrite nitrogen and nitrate nitrogen in the simulated seawater recirculating aquaculture system.The content of this dissertation consists of the following fields: the selection of the raw materials used,the dosage of the promoter and initiator,and the choice of additive used in the preparation of the embedded immobilized microorganisms;the domestication of the embedded immobilized microorganisms and the removal of ammonia nitrogen,nitrite nitrogen and nitrate nitrogen in domestication stage;the domestication of the embedded immobilized microorganisms and the removal of ammonia nitrogen,nitrite nitrogen and nitrate nitrogen in domestication stage in the simulated seawater recirculating aquaculture system.In the synthesis process of the polyurethane prepolymer,the reaction between TDI or IPDI and PPG,TDI polyurethane intermediates or IPDI polyurethane intermediates and HEMA are the second-order reactions.This dissertation chooses IPDI as the raw material of the preparation of the embedded immobilized microorganisms,65 ? as the optimum reaction temperature and 4h-5h as the optimum reaction time.The reaction rate constants are 0.017mol/kg*min and 0.012mol/kg*min,the corresponding activation energy are 45.44kJ/mol and 127.03kJ/mol.In the preparation of the embedded immobilized microorganisms,according to the synthetic reaction rate and the actual processing results of ammonia nitrogen removal.The composition of embedded immobilized microorganisms used in this dissertation is polyurethane prepolymer 10%,initiator KPS 0.2%,promoter TEMED 0.1%,additive active carbon powder 3%.In seawater recirculating aquaculture system's simulation experiment,the domestication period lasts 58 days,higher than that of fresh water.In the process,the removal rate of ammonia is more than 90%,the removal rate of total nitrogen is more than 70%.After the domestication period,the ammonia nitrogen concentration is lower than 0.02 mg/L,the nitrate nitrogen concentration is lower than 0.1 mg/L,the nitrite nitrogen concentrations less than 50 mg/L.Experimental results show that the embedded immobilized microorganisms can effectively remove three forms of nitrogen.The embedded immobilized microorganisms have good potential for application in the recirculating aquaculture system.