Study On Algae Analysis And Control Technology In Surface Water Source Of A City

The excessive growth of various algae in water not only affects the appearance,but also causes problems such as green,black and smelly water bodies,and even causes excessive algal toxin in water bodies.In this study,the species and quantity of algae in reservoir no.1 and reservoir no.2 were analyzed from different time and space.According to the test results of chlorophyll a,total phosphorus,total nitrogen and permanganate index in the two reservoir areas,the eutrophication degree of the two reservoir areas was evaluated by the comprehensive nutrition index method,and the treatment Suggestions were given.Based on the detection results of algae in raw water in no.1 reservoir area,the optimal control scheme of algae in surface water source was developed and verified.Seven algae gates were detected in no.1 reservoir,namely,chlorophyta,diatoma,euglenophyta,cyanophyta,cryptolophyta,dinoflagellate and aureophyta.There was a difference in time and space,and the total peak was above 10~8/L.Algae in no.2 reservoir consists of 7 phyla,which are chlorophyta,diatoma,euglenophyta,cyanophyta,cryptolophyta,dinoflagellates and aureophyta.Algae starts to grow in late summer and lasts all autumn until winter.The mean number of algae was5.10×10~6/L.The analysis of eutrophication degree of two reservoirs showed that the total phosphorus,total nitrogen and chlorophyll a in no.1 reservoir exceeded the eutrophication limit of water body,and no.1 reservoir was N and P type eutrophication.The comprehensive nutritional status index was 54.54～66.33,and the nutritional status was light to moderate.The total P and total N in no.2 reservoir exceeded the single index standard of eutrophication.The content of chlorophyll a exceeded the single standard of eutrophication,and the comprehensive nutrient status index was 47.73～48.99,belonging to the medium nutrient status.The result of algae removal experiment shows that activated carbon has good adsorbability and can be added when water contains a lot of algae and high concentration of organic matter.Chlorine dioxide,longed for can easily,and potassium permanganate and composite iron and aluminum joint application,able to handle the high algae water well,the best dosage of 0.4mg/L of potassium permanganate,easy longed for can the best dosage of 2.7mg/L,chlorine dioxide,the best dosage of 0.4mg/L,the quantity of the algae to 10~4/L,the algae removal rate reached more than 99.81%of microcystin algae toxin concentration significantly lower than the raw water,the removal rate reached more than 95.12%.