Các thông số chất lượng nước lớn và ứng dụng TƯƠNG TÁC GIỮA CÁC 3,1 thông số chất lượng nước Chương này giao dịch với các thông số quan trọng chất lượng nước được sử dụng như là các biến kiểm soát đó, Những người đó mạnh ảnh hưởng đến hành vi của các thành phần khác hiện diện trong nhiều nước. Việc kiểm soát các biến số chính là độ pH, oxy hóa khử (oxi hóa khử) tiềm năng, nồng độ axit và kiềm, nhiệt độ, và chất rắn hòa tan Tổng số (TDS). Điều này thảo luận về chương aussi. | 3 Major Water Quality Parameters and Applications INTERACTIONS AMONG WATER QUALITY PARAMETERS This chapter deals with important water quality parameters that serve as controlling variables those that strongly influence the behavior of many other constituents present in the water. The major controlling variables are pH oxidation-reduction redox potential alkalinity and acidity temperature and total dissolved solids TDS . This chapter also discusses several other important parameters such as ammonia sulfide carbonates dissolved metals and dissolved oxygen DO which are strongly affected by changes in the controlling variables. It is important to understand that chemical constituents in natural water bodies react in an environment far more complicated than if they were surrounded only by a large number of water molecules. Various impurities in water interact in ways that can affect their chemical behavior markedly. Water quality parameters defined above as controlling variables have an especially strong effect on water chemistry. For example a pH change from pH 6 to 9 will lower the solubility of Cu2 by four orders of magnitude. The solubility of Cu2 in water at pH 6 is about 40 mg L while at pH 9 it is about 4 X 10 31 mg L 10 000 times smaller. If for example a water solution at pH 6 contained 40 mg L of Cu2 and its pH was raised to 9 all but 4 X 10 31 mg L of the Cu2 would precipitate as solid Cu OH 2. As another example consider a shallow lake with algae and other vegetation growing in it. Its suspended and bottom sediments contain high concentrations of decaying organic matter. The lake is fed by surface and groundwaters containing high concentration of sulfate. During daytime photosynthesis can produce enough DO to maintain a positive oxidation-reduction OR potential in the water. At night photosynthesis stops and biodegradation of suspended and lake-bottom organic sediments consumes nearly all of the DO in the lake. This changes the water from oxidizing .
