SU791614A1 - Method of waste water purification - Google Patents

Description

one

The invention relates to the treatment of industrial wastewater with chemicals for the chemical flotation of contaminants, more specifically, to wastewater treatment of the production of raw benzene from coke oven gas, emulsified oils, oxidation products and polymers in oils, resins, fine particulate matter, benzene. , phenols, sulphides and can be used in the coke and chemical industry.

The known method of wastewater treatment simultaneously from oils, resins, benzene, phenols, sulfides and solid particles by chemical flotation with bubbles of gases formed during the interaction in the alkaline environment of a peroxide substance with permanganate, which involves the simultaneous flow of the following processes: oxidation of organic and inorganic impurities with the formation of gaseous products; the formation of flaky oxides of manganese; sorption of oil together with benzene, smolgiii and phenols by flaky oxides of manganese; catalytic decomposition of peroxide substances with the formation of active

oxygen; carbonization of sulphides by carbon dioxide resulting from the oxidation of organic impurities / flotation of oils, finely dispersed solid particles and flaky manganese oxides together with sorbed oil, benzene, and phenols l. However, the treatment of wastewater by a known method requires a large consumption

10 expensive reagents.

It is caused by the fact that in an alkaline medium, flaky manganese oxides, sorbent impurities and floating gas bubbles in the foam phase,

15 is formed only from permanganate upon its interaction with impurities and peroxide.

The aim of the invention is to reduce the cost of the cleaning process by reducing the consumption of permanganate with a similar degree of purification.

The goal is achieved by the fact that the treatment of wastewater with permanganate and peroxide

25 in particular, potassium permanganate and hydrogen peroxide, carried out in the presence of metal salts that catalyze the decomposition of the peroxide substance and form hydroxides. As metal salts, manganese and / or iron soybeans are used to increase the degree of purification; the cleaning process is, if necessary, terminated from suspended substances, by filtering the aqueous phase through a granular loading filter, which uses activated carbon / OR quartz sand.

The essence of the proposed method is that, when treating alkaline wastewater, initially with metal salts, and then successively with permanganate and peroxide substance, the main amount of flocculent particles that can sorb oils together with organic impurities and resins, catalyze the decomposition of the peroxide substance and flotation - formed directly from metal salts introduced into water, the cost of which is significantly lower than the cost of permanganate. At the same time, the consumption of permanganate for water purification is significantly reduced.

When the aqueous phase is filtered through quartz sand and activated carbon, mechanical purification of the remaining suspension and adsorption purification from dissolved organic impurities occurs. In addition, in the process of filtering water, the unreacted peroxide substance decomposes. The wastewater treatment method is carried out as follows.

With alkaline waste water (pH 8), additives of metal salts, permanganate and peroxide are added with its stirring. Shake the treated water vigorously, defend and after the flotation of the impurities, the clarified water is passed into the foam phase through a filter with a granular load. Primary wastewater treatment

water salts of metals helps to reduce the consumption of permanganate and deeper clarification of waste water. As metal salts, manganese and / or iron salts are used, which are cheaper than permanganate and, in an alkaline medium, form hydroxides well sorbing oils together with organic impurities and resins, float well together with impurities of gas bubbles in the foam phase. In the quality, granular loading use activated carbon and / or quartz sand, which adsorb organic impurities well and trap mechanical impurities from water.

Example. One liter of highly emulsified and turbid waste water is used to produce raw benzene from coke oven gas (pH 9, T 20c), containing on average up to 2.5 g of salt absorption oil and tar, 90 kg of benzene, 1.0 mg of phenols, 340 mg of sulfides and Up to g of fine solids and having a strong smell of salt oil, benzene, phenols and sulphides are added at. stirring 0.4, 0.6 g FeSO, 0.2 g KMPO, and then

1d. - Shake the treated water vigorously for 1-3 seconds.

and defend. The gas bubbles formed throughout the whole volume float the impurities of water into the foam phase. Almost complete clarification of the water is reached in 0.5 minutes. After filtration of clarified wastewater, a layer of quartz and activated carbon does not detect any odor and impurities. Cleaning time no more

2 minutes.

For comparison, wastewater treatment of the composition according to the known method is carried out. The results are presented in the table.

Proposed 0.2 1.0 0.4

Known1, 0 1.0 ny

The effect of using this Wastewater Treatment Method, including the treatment of wastewater with manganese and / or iron salts, with permanganate and a peroxide substance, provides less consumption of permanganate and, therefore, reduces the cost of treatment without changing the degree of purification.

0.6 100 2.0 100 2.6

Claims (3)

1. Wastewater treatment method of producing raw benzene from coke oven gas, including reagent flotation using permngunate and peroxide substance in an alkaline medium, different By the fact that, in order to reduce the cost of the process by reducing the consumption of permanganate with an anasogic degree of purification, the process is carried out in the presence of metal salts catalyzing the decomposition of the peroxide substance and forming hydroxides. 2. Method pop. 1, inconsistent with the use of manganese and / or iron salts as metal salts. 3. Method according to paragraphs. 1 and 2, that is, because with a view to increasing the degree of purification from suspended substances, the purification process is completed by filtering the aqueous phase through a filter with a granular load, which is activated carbon and / or quartz sand. Sources of information taken into account in the examination 1. USSR Author's Certificate in Application No. 2734642 / 29-26, cl. C 02 C 5/02, 01.03.79.