RU2643047C2 - Combined method for cleaning natural bischofite brine - Google Patents

Abstract

FIELD: pharmacology.

SUBSTANCE: invention is a medicinal product, a balneological agent, a preventive agent used in various pathological conditions of the body, as a means of preventing diseases of various etiologies, as a balneological factor in a sanatorium-resort therapy or as an active constituent for the preparation of complex drug formulations. The source raw material is pre-aerated. The raw material is then passed through filtering installations containing granular activated carbon. Further, the raw material is subjected to mechanical filtration through a filtering membrane and nanofiltration through membranes to remove dissolved substances with a size of 1 nm and organic substances with a molecular weight of 200-400 Da.

EFFECT: obtaining purified natural bischofite brine from impurities of iron ions, oil products, heavy metal salts and suspended mechanical particles.

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Description

The invention relates to medicine, pharmacy and balneology and is a medicine, balneological agent, prophylactic agent used for various pathological conditions of the body, as a means of preventing diseases of various etiologies, as a balneological factor in spa treatment or as an active component to obtain complex dosage forms.

The bischofite mineral is magnesium chloride hexahydrate; its deposits were discovered in vast areas of the Caspian Basin and the Volga monocline at depths of up to 2000 m. Industrial bischofite mining is carried out by underground dissolution, which allows the extraction of 75-85% bischofite brine.

Our proposed bischofite purification method implies a rational approach with the aim of removing (reducing the content) of such impurities as iron ions, oil products, salts of heavy metals and suspended mechanical particles.

Bischofite is purified by using the combined filtration method, which consists in preliminary aeration of the initial brine, followed by passing through filtering units containing granular activated carbon, mechanical filtration and final adjustment of the chemical composition as a result of nanofiltration.

Preliminary aeration of the starting brine is carried out in a vacuum ejection apparatus.

The device provides air supply up to 20 m ³ per 1 m ^{3 of} brine. Upon contact with air, iron and other readily oxidizing substances are oxidized. Next, the brine is pumped to a filter loaded with granular activated carbon.

Activated carbon based on coconut shell is used, since such grades of coal have the best indicators of sorption capacity, and have sufficient mechanical strength, which allows it to be used, among other things, to remove iron in low concentrations in the initial solutions.

To obtain high cleaning results, coal should have the following technical characteristics: bulk density> 0.48-0.52 g / cm ³ , iodine number> 1050 mg / g, carbon tetrachloride activity> 55%, sorption capacity for methylene blue> 240 mg / g, humidity <5%, hardness> 95%, ash content 5%.

The next step in the purification of bischofite brine is mechanical filtration. For this purpose, polypropylene filtering membranes are used that provide a delay of 5 micron particles.

The final adjustment of the trace element composition of bischofite brine is carried out by nanofiltration.

Separation occurs using a membrane having a less dense and more permeable selective layer than for reverse osmosis, so the nanofiltration membranes used have reduced selectivity, increased permeability and lower working pressure at a given performance. In the process of nanofiltration, components of dissolved substances with a size of 1 nm and organic substances with a molecular weight of 200-400 Da are effectively retained. During operation, a working pressure of 3-20 atm is maintained, depending on the required performance.

Passing through the membrane, the brine is cleaned of suspended mechanical and colloidal particles, microorganisms, organic compounds and salts of heavy metals, oil products.

During the operation of membranes, colloidal impurities, iron ions, heavy metals, organic compounds, microorganisms are deposited on their surface. This leads to a decrease in productivity, deterioration in the quality of work and degradation of the membranes.

To do this, during the operation of the membranes, the indicator of the colloidal index of the liquid (brine) supplied to them is controlled, determined by a special technique (colloidal index of 3 or less - stable operation; from 3 to 5 - acceptable operation; more than 5 - it is not recommended to apply brine to nanofiltration plants ) Such control does not allow to reduce the quality of brine cleaning.

The essence of the invention lies in the use of combined cleaning methods - the simultaneous deposition of chemicals and filtration.

The aim of the invention is to obtain a purified natural bischofite brine that has passed the purification stage, which allows to obtain a bischofite mineral brine having the characteristics shown in table 1.

Claims (1)

The method of purification of natural bischofite brine from impurities by a combined cleaning method, characterized in that the initial bischofite brine is aerated, then passed through granular activated carbon, a filtering membrane for mechanical filtration and nanofiltration membranes to remove dissolved substances from 1 nm in size and organic substances with molecular weighing from 200-400 Yes.