Studies On Coagulant Characteristics Of Min River With Polyferric Sulfate

Drinking-water safety directly relates to human health.How to improve the water quality of water plant has become one of the major problems to be urgently solved in the field of water supply engineering.Coagulation technology is a key production chain in water purification process.This water treatment process has an important effect on the water quality in which the choice of coagulant is very important.At present polyaluminum chloride(PAC) is usually used as the coagulant in many water supply plants.As a result,this leads to the aluminum content of the potable water increasing which is not of benefit to the drinking-water safety.Using polyferric sulfate(PFC) as the coagulant,the purification efficiency of Min River is studied in this thesis.Through the indoor and site field experiments,the coagulant characteristics of PFS and PAC are contrastively analyzed.The main work and results are as follows.1.It can be found from indoor experiments that the removal of turbidity with PFS tends a trend of linear increase,and on the conditions of 5℃,10℃,15℃and 19℃,the percents of turbidity removal can exceeds 95%when the accessorial quantity arrives at 40mg/L.In contrast with the turbidity removing efficiency of PAC, PFS can get better effects than PAC.2.The experiment results indicate that PFS can reduce more the pH value of water than PAC in any temperature and the maximum decrease value is about 0.6 over the corresponding value of PAC.3.The site field experiment shows that the aluminum content of treated water with PFS is less than 0.02mg/L,but in the same condition the aluminum content of treated water with PAC is as 10 times as the PFS corresponding value.The aluminum contents of treated water with PAC can be 4 times over the raw water.4.The water treatment with using PFS can reduce more electrical energy than that of PAC,its cost of coagulant also can be reduced over 16%than that of PAC.