CZ59794A3 - Method of treating water contaminated predominantly with oil component by the action of bentonite - Google Patents

Abstract

Firstly, the natural bentonite is mixed e.g. with polluted water, and then a stream of this mixture is made, being put advantageously into the milling/mixing pump. In this pump the mixture is pressurized in the range 0.1 - 1000 MPa and milled and stirred under local alternative acceleration and retardation in the range 5 - 500 m/s. The originated suspension can be further activated by an organic flocculant.

Description

Method of water treatment by bentonite contaminated mainly by i_O-Laj-Ova component

Technical field

The present invention provides a process for treating water contaminated predominantly with an oil component by the action of bentonite in the form of an aqueous suspension.

BACKGROUND OF THE INVENTION

So far, the sorption and flocculation properties of bentonite and other clays from the montmorillonite group have been increased by their chemical treatment. The purpose of such treatments is to bind the chemical flocculants to the bentonite structure and thereby inducing a stronger flocculation effect than the bentonite itself is capable of. Ten | -pak | preferably, due to its specific ability, it loads the sludge _; and thereby significantly accelerates its sedimentation.

For example, the mechanical-chemical treatment of an aqueous suspension of bentonite in an iron, iron or aluminum cycle is known in an amount dependent on water contamination. Wet bentonite with aqueous activating agents are also known to treat bentonite with chlorides, sulphates, suspensions in which the reagent is a group of nitrates, hydroxides and phosphates dosed depending on the amount of bentonite used. Treatment of bentonite with mineral acids, hydrochloric acid and / or sulfuric acid is also known.

These acids are mixed with bentonite at elevated temperatures and vigorous stirring. As a result, the metal part of the base material is extracted from the bentonite and at the same time the remaining material increases its volume and its microporous size. The extracted metal salts and excess acid were then separated, the resulting product was washed, dried and ground. Sometimes still

The extraction carried out additional extraction, for example with hydrochloric acid, but at the expense of the adsorption capacity of the activated bentonite.

Photo

A more modern way of bentonite, ongoing stages, bentonite acid. performs

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The first step is a continuous countercurrent activation at boiling point in two to four steps, a fine-grained suspension of the extracted metal salt is entered, and the remainder of the last step is entered with an acid solution and a suspension of the extracted bentonite. It is then washed, dried, ground and sorted.

then

The disadvantage is the consumption of the existing chemicals i, the methods of activation of salinisation waste demands and additional costs for the process and washing of activated bentonite.

Bentonite is high water, energy purification water from the activation

SUMMARY OF THE INVENTION

Said drawbacks in the considerable treatment of water contaminated predominantly with bentonite in the form of an aqueous suspension at a temperature of 5 to 25 ° C.

It is an object of the present invention to mix natural bentonite with contaminated water to form a stream which is pressurized to 0.1 to 10 alternately accelerated and retarded in m / s, while mixing and vigorously mixing. Preferably, an organic flocculant may be added to the suspension prior to mixing.

The process removes the process by the oil component by the action to be treated at

The MPa and the stream of the mixture then range from 5 to 500

The process according to the invention has been verified in industrial waters. Its advantage is the use of chemical additives, a considerable increase in the sorption properties of activated bentonite and a reduction in the environmental burden of waste chemicals.

in a wastewater treatment plant eliminating the necessity

DETAILED DESCRIPTION OF THE INVENTION

Example 1

Per 1 m ³ of car wash washer temperature of ^ C, containing 0.52 mg / l of non-polar petroleum substances (NEL), 2 kg of ground, unactivated bentonite from the Obrnice bearing was dosed via the hopper of the grinding and mixing pump. The mixture was sucked through a grinding and mixing pump and pressurized to 0.3 MPa. (Pal ^ was up to 500 m / s at local alternating acceleration. This process resulted in grinding and stirring and retarding within 5 to activate bentonite and adsorption of petroleum substances to the surface. polyacrylate in an amount of 1 polymeric flocculant per kg of flocculent bentonite followed by rapid sedimentation.

g cat ionactive There was created

Purified waste water was subjected to laboratory analysis and was found to contain 0.257 mg / l NEL.

Example 2

Per 1 m ^{3 of the} same waste water, 5 kg of the same bentonite was dosed through the hopper of the grinding and mixing pump at the same temperature. Water was cleaned to 0.032 mg / l NEL using the same procedure.

Example 3

Per 1 m ³ of the polluted wastewater from the carwash station, containing 0.52 mg / 1 NEC was added to the used oil content and therefore increased NEL 4 [000 mg / 1 NEC. 4.44 kg of ground bentonite from the Obrnice bearing was dosed through the hopper of the grinding and mixing pump. The mixture was sucked through a grinding and mixing pump and pressurized to 0.5 MPa. Following the procedure described in the previous examples, bentonite was activated, oil emulsified, and oil products sorbed in various forms to bentonite grains. Addition of 2 g of polyacrylate-based cationic polymeric flocculant per kg of bentonite resulted in the formation of floccules followed by rapid sedimentation.

Purified water contained 0.24 mg / l NEL.

Industrial applicability

The process according to the invention can also be used in analogous processes in which fine grinding and mixing of e.g. bulk powders in liquids to form suspensions or emulsions from liquids and various substances, not just bentonite.

Claims (1)

PATENT CLAIMS Process for treating water contaminated predominantly with an oil component by the action of bentonite in the form of an aqueous suspension, which is treated at a temperature of -5 to 25 ° C, characterized in that the natural bentonite is mixed with the contaminated water. [whereupon! from this mixture to a pressure of 0.1 to 10 MPa and Vpakj and retarded in the range to form a stream, which is the mixture flow alternately at a speed of 5 to 500 m / s, pressurized to accelerate while the mixture is ground and vigorously stirred.