Study On The Inactivation Of Microorganisms In Water And Algae And Performance Mechanism By Pulsed Light

As the source of life, water is indispensable to all life on earth, life, is human survival and development of material resources, is the human production, life and maintain a good ecological environment is an integral part of basic conditions, and is the only irreplaceable in the nature, repeatable use of natural resources, it has many functions, including life support, production support functions, maintaining environmental functions, in addition to this, such as power generation, shipping, landscape and natural beauty is the most important function of water resources. But with the rapid development of the human society, production, economic and other fields, the demand for water is increasing, making a tense situation appear in short supply of water resources, the rapid development, at the same time worsening water pollution caused by a variety of industrial production, and how to reduce or even avoid the secondary pollution, eliminate harmful substances by micro-organisms and other micro-organisms in the water to become more and more the focus of attention of the people in the field of water treatment and disinfection.Disinfection method used in water treatment at home and abroad, traditional water treatment method using chlorine as usually drinking water disinfection chemicals, although strong chlorine oxidation and good processing effect is widely recognized, but chlorine disinfection is easy to produce halogenated disinfection by-products such as harmful, and decrease the security of water. As emerging oxidation technology of pulsed light flash technology, according to the method is simple operation, high processing efficiency, no secondary pollution, etc. Advantages are paid attention to by the researchers at home and abroadThis thesis using pulse light sterilization technology to kill microorganisms in natural water, inactivated Microcystis aeruginosa in water body, through optical microscope and scanning electron microscope Microcystis aeruginosa after pulse light flashes according to inactivate the cell morphological changes and study the mechanism of inactivated. The results show that:(1) Pulsed light inactivation of microorganisms and Microcystis aeruginosa in natural water, there is a strong lethal effect, has a good application prospect in the field of drinking water disinfection.(2) Experiments of microorganisms inactivated rate and experimental device of flash according to frequency and the input voltage, according to the more, the device input voltage, the greater the microorganisms inactivated effect is better;(3) Under different conditions of the water quality factors, the total number of bacteria in the Songhua River water samples by pulse light flashes according to inactivate the effects of different effect. Low temperature of watery broth after pulse light flashes according to the inactivated effect is better than the inactivated effect of high fluid temperature. Microorganisms in water with the increase of solution turbidity inactivated rate gradually decreased; Solution pH value of5.68,7.45, and9.12in the solution, after pulse light flashes according to the changed the nature of the ions in the liquid, inactivated rate7.26logarithm reached7.26a logarithmic, respectively,7.33log, so the pulse light in weak alkaline solution of inactivated effect is better(4) Microcystis aeruginosa inactivated effect by the pulse light flash according to the input voltage, pulse frequency, water temperature, turbidity, and factors such as initial solution pH value; Appropriate increase pulse light flashes according to frequency and the input voltage can improve the inactivated rate of algae; Within the scope of the algae, the optimum growth temperature, inactivated effect is good; As the algae solution turbidity is more and more big, the inactivated rate gradually decreased, the turbidity of inactivated effect; In appropriate patina of algal growth pH range, the weak alkaline seaweed liquid treated by pulsed light produced by the algae inactivated effect is good in weak acid.(5) Through optical and electronic electron microscope observation, combined with the existing experimental results speculated that cause patina of algal cell death is caused by pulse light flashes according to the common effect of physics and chemistry. Light pulse discharge damage the outer structure of algal cells, cells appeared a lot of holes, intracellular thylakoid phycobilisome destroyed, and is a major cause of lead to cell death.