Study On Degradation Pattern Of Two Biocides In Seawater

Water treatment agents are one of the key technology in seawater circulating cooling system, the biocides of which has function to kill bacteria and the algae, which results in potential hazards to environment. The paper studies degradation of SW303 in three levels that are static experiment, self-made water flowing equipment and dynamic analogue device, analyzes the influence to results at the length of the factors as concentration factor, initial concentration and pH. Meanwhile, degradation of SW303 and quaternary ammonium salt is compared in static experiment, through which friendly character to environment is also discussed. The following are the conclusions.(1) The degradation ways of SW303 are biodegradation, photolysis, and less hydrolysis. Degradation of quaternary ammonium salt is completed via biodegradation, photolysis, and hydrolysis. Results have no obvious difference from spent hours and final percentage.(2) The natural attenuation of SW303 goes beyond that of quaternary ammonium salt in the environment.(3) It is identical in static experiment considering noticeable factors (natural factors, including water quality, organisms and light, etc. simple technology parameter to system, for example, supplementary-discharged water).(4) Results indicated there is some difference between actual and theoretical values, so attenuation of SW303 in seawater circulating cooling system can't be considered to be caused by biodegradation, photolysis and discharged water.It's first to study biocides on degradation pattern in seawater in the world. It is necessary to further perfect related experiment and theory combining to real process of seawater circulating cooling technology, which could provide dependable technology basis for environmental impact assessment of seawater circulating cooling engineering and accelerate the green progress of seawater circulating cooling technology.