SU582210A1 - Method of thermal detoxication of waste water containing organic acids - Google Patents

Description

one

The invention relates to methods of thermal treatment of waste water containing organic acids, and can be used in the treatment of chemical, petrochemical, forestry and other industries.

The known method of thermal disposal of wastewater containing organic bring, including the complete evaporation of the source effluent with flue gases and the subsequent combustion of vapors with the use of water 1.

The disadvantage of this method is the fuel consumption for evaporation of water and for combustion.

The closest to the invention of the technical essence and the achieved effect is the method of thermal neutralization of wastewater containing organic liquids, including evaporation of the initial wastewater due to heat recovery of flue gases and subsequent incineration 2.

However, during the thermal neutralization of wastewater by this method, volatile organic substances are released during the evaporation process, which leads to pollution of the atmosphere and additional costs for the afterburning of the resulting vapors.

The aim of the invention is to protect the atmosphere from pollution and reduce the cost of the process.

This is achieved in that the evaporation is carried out in the presence of an alkaline reagent.

In this case, the solid residue from incineration is used as the alkaline reagent.

The method is as follows.

Wastewater is sent to a neutralizer, where an alkaline reagent is also introduced — the accumulated solid residue from incineration, which is oxides or carbonates.

alkali metals. In this case, m volatile organic acids are converted into salts of these acids, which, as a rule, are less volatile than the acids themselves.

Neutralized effluent is directed to

evaporation, carried out by the heat of high-temperature flue gases. One stripped effluent with salts of organic acids is fed for incineration. As a result of the combustion of water, it is islated, its vapors overheat, the salts of organic acids are oxidized to form carbon dioxide, water, and the corresponding oxides or carbonates of alkali metals, which are converted into a solid residue returned to the neutralizer.

Example. Wastewater from the production of plastics containing acetic acid at a rate of 3 mWh is sent to a neutralizer, where alkaline reagent sodium carbonate is also introduced. As a result,

sodium acetate, a practically non-volatile compound. Neutralized effluent is evaporated with flue gases with a temperature of –1000 ° C to a sodium acetate concentration of 11% and a decrease in the flow rate in the liquid phase to 1.1. The flow is squeezed in the oven. The resulting solid residue is removed from the furnace in the form of a melt, which is cooled, crushed and sent as an alkaline reagent to a neutralizer.

The method provides protection of the atmosphere from pollution and does not require additional, after-burning costs of the resulting vapors.

Claims (2)

1.-Sp.o.About thermal treatment of wastewater, water / containing organic acids, including evaporation of initial wastewaters and subsequent incineration, characterized in that, in order to protect the atmosphere from pollution and reduce the cost of the process, evaporation is carried out in the presence of an alkaline reagent . 2. A method according to Claim 1, characterized in that the solid residue from burning the waste is eliminated as the alkaline reagent. Sources of information taken into account during examination 1. Dybenko V.M. et al. Deactivation-sewage disposal in installations with deep re-generation of flue gas heat. - “Chemical: 3: Pr.M.Ischennost, 19.75,; No. 5. 2. Bernadiner, M.N., et al. Thermal methods for the disposal of industrial wastewater from chemical plants. ,THEM. D.I. Mendeleev, Sh72, 17, No. 2, p. , 162-168.