Treating abattoir waste water to reduce COD - by adding sodium bentonite, polyvalent metal flocculating agent and flocculation auxiliary, e.g. acrylamide-acrylate copolymer

摘要

Waste water from albatross is purified by treating with; (1) 0.1-2 kg/cu.m of an Na bentonite (I) of high swelling capacity nad ion-exchange capacity (IEC) 60-110mVal/100g. which in aq. suspension produces a pH of 10-11; (2) as cationic flocculating agent (II) a soluble polyvalent metal salt or hydroxide at 50-1000m Val cations/cu.m., and (3) 0.2-15g/cu.m. of a cationic or anionic flocculation auxiliary (III) as aq. soln. The ratio of (1): (2) is such that before addn. of (3), the water has pH below 6.8 (opt. with addn. of acid). Pref. component (2) comprises as major components Al203 (Sic), FeCl3, CaCl2 and/or MgCl2, esp. an aq. soln. contg. (g/l) AlCl3, 45-60; FeCl3, 15-25; CaCl2, 4-8 and MgCl2, 9-15 at 0.3-3 l/cu.m. waste water. USE/ADVANTAGE - This method provides rapid and simple redn. in the COH of the water (in examples to about 11-15% of the original value) and good sepn. of the flocculated solids. Addn. of (3) provides a greater level of purification than possible with (1) and (2) only. The flocculated material can be used as cattle fodder and feed supple