SU861335A1 - Method of waste water purification - Google Patents

Description

.I Ieo6retvSh {e relates to purification and remediation grind off the water and can be used for about shstkn grind off water soderzhaaschh ft (f and zfugie 0redp | e impurities obraeukschies The HFOs | 1zvodstve extraction phosphorus hydrochloric ioHcnoibi and mineralyshh fertilizers, as well as ferrous and nonferrous metallurgy. The most widely used method of disposal of wastewater with milk of lime. Reduction of fluoride in, and neutralized solutions is achieved Additional purification, it is known the scavenging of fluoride from fluorine-containing effluent of lime and subsequent addition of alumina networks} discloses a method of treating wastewater excess amount of lime introduced in several steps, followed by evaporation otdeleg cue precipitate RF) etsenshlh effluent I2j. When treating sewage using the following methods, the formation of 1C1F {if insoluble fluorine compounds has a very low wasp rate of 2 ppm (, 2-0.3 m / h). To improve the effect of clarifying neutralized effluent, you can add coagulation additives, such as polyacrypamide (PAA) and earth (AI (SO) iron sulfate (FeSO), etc. Io) and with the use of a receiver, the rate of clarification of neutralized suspensions is low and does not exceed 2-3 m / h. The most common approach to the technical essence and the achieved result is the method of sewage treatment of the production of mineral fertilizers of the following composition, mg / l: 975% 05 70 R; pH of the solution 2.8. Acid drains are neutralized with lime milk containing 8 -10Z C aOdifr, within 30-40 minutes to a pH of 6.7-8.5, 0.11% PAA is added in a quantity of 10 mg / l, the rate of clarification of the suspension is measured, the value of which is 3.5-6.0 The clarified water contains 40-50 mg / l of suspended solids, 6-31 mg / l and 19-45 mg / l of F-C3. The main disadvantage of this method is the relatively low rate of clarification of the suspension, which prolongs the cleaning process In addition, additional difficulties in production conditions create the need for coagulant use. The chain of the invention is to increase the rate of sludge separation and simplify the process with a similar degree of wastewater treatment. The goal is achieved by the fact that wastewater is neutralized with KoBbfM lime milk in the presence of calcium sulfate at a ratio of CaO: CaS 32-A2i, followed by separation of the precipitate. It is advisable to neutralize phosphorus from the decomposition of phosphogypsus, a waste product from the extraction of phosphoric acid. The method allows to intensify the wastewater treatment process by increasing the sedimentation rate of the suspension by 20-50% and simplify it by excluding from the process of using phpacacanth, for example polyacrylate amide. phosphoric acid makes it possible to reduce the cost of wastewater treatment. The introduction of calcium sulfide in an amount less than this results in a decrease in the rate of clarification of the suspension, and an increase in the amount of injected CaS impairs the quality of the clarified water {due to an increase in the amount of suspended matter in it). Example I. 1000 MP waste water for the production of extraction phosphoric acid containing 6080 mg / l P and 2250 mg / l PjOg is neutralized with 9.5% lime milk with the addition of 0.342 g CaS (CaO: CaS ratio of 37.5 for 40 minutes to a pH of 7.9. The resulting suspension is clarified within 1 hour. The clarification rate is 9.2 m

In this case, the clarified water contains

21 mg / l suspended solids; 20.14 mg / l

Claims (3)

F and 4.0 mg / l Pr05 neutralization is carried out in the presence of calcium sulphide with a ratio of € aO: CaS (32-42) :, 5 Example 2. 1000 ml of the original in-. dyes containing 6080. mg / l F and 2250 mg / l 1% n are trated with 7.8% lime milk, prepared from phosphoizate, for 40 minutes to a pH of 7.75. The correlation between CaO and CaS in milk is 32.3 g1. The resulting suspension is clarified for 1 hour. The rate of clarification is 4.2 m / h with a content of 85 mg / l of clarified water of 15.6 mg / l F and 18 mg / l in clarified water. PRI me R 3. 1000 ml of source water containing 6080 mg / l F and 2250 mg / l% 0; Neutralized with 9.3% lime with 1m milk made from phosphoizate for 40 minutes to pH 7.5. The ratio of CaO and CaS is 41: 1. The suspension is clarified at a rate of 4.5 m / h with the content of clarified water in the clarified water of 49.7 mg / l, 23.5 mg / l F and 14.5 mg / l. PRI me R 4. 1000 MP initial water containing 13PO mg / l F, 400 mg / l is neutralized with% milk of lime prepared from phospho-extract for 40 minutes to a pH of 7.7. The ratio of CaO and CaS in milk is 53: 1. The clarification of the suspension obtained was carried out at a speed of 0.84 m / h. The content suspended in clarified water is I14 mg / l F 22.04 mg / l and P-0 1.0 mg / l. The feasibility of the proposed method is that the sedimentation rate in the clarified suspension increases by 3-7 Once compared to the method, in KOTpptM, the distillation is carried out with one milk of lime (without CaS). The method can be prevented by eliminating the use of coagulant and making good use of phosphoiz in the form of waste. Claims, a method for treating wastewater, including neutralizing them with lime milk followed by separating sludge, o t and more, so as to increase the rate of sludge separation and simplify the process with a similar degree of purification 5861335 6 2. The method according to claim 1, about t and h and y-, 1. J. Water and Waste. 20, No. 6, c. and with the fact that, with the udeshev- chain, .1978, s, 667-674, the laziness of the process, the neutralization of the Osu-2, Japan Patent No. 52-85085, the phosphoizme is obtained obtained by the. C 02 C 5/02, published 1977. during the decomposition of phosphogypsum - waste j, the production of phosphorus extraction 3. Referential Cleaning acid emissions and equipment, sources of information, hazards on chemical plants taken into account in the examination, 6,: 1977, p. 2-4