RU2421277C1 - Method of producing sorbent for water treatment - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to water treatment in a domestic water supply system. Sorbent for water treatment is obtained by mixing drilling wastes with portland cement-500 in ratio 1:1 in the presence of water. The obtained material is solidified and washed in washing water until the test for the chloride ion is no longer negative.

EFFECT: obtaining efficient sorbent from drilling wastes.

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Description

The invention relates to the field of environmental protection, in particular to the production of an environmentally friendly aluminosilicate sorbent for purifying water from heavy metal ions and a number of organic compounds in a drinking water supply system. The core of the sorbent is drilling waste, in which Portland cement 500 is added to increase strength.

A solution is known that relates to the treatment of wastewater containing anionic surfactants (SAS), and can be used in various fields related to their industrial use. The invention is intended to increase the degree of wastewater treatment from surfactants. To achieve this goal, a cleaning method has been developed, including an electrocoagulation operation, the time of which is 10-40 minutes, and shungite is used as a sorbent. It is advisable to use shungite calcined at a temperature of 500-550 ° C for 2-3 hours [RU 93055727 A].

The invention is described, which relates to the field of water purification for domestic, drinking and technological purposes and can find application for purification of natural (underground and surface) and technogenic waters from organic compounds - humic and fulvic acids, which determine the color of water. The cleaning method involves contacting contaminated water with a sorbent, brucite being used as a sorbent. In a preferred embodiment of the method, sorption is carried out by filtration through a layer of brucite. The implementation of the method is also provided by adding brucite with a particle size of less than 0.1 mm in the treated water, followed by separation of the precipitate. The invention provides high quality water purification and a cheaper process by using a natural sorbent [RU 2315003 C1].

A composite sorbent is described, including a porous sorption material with an inorganic sorbent formed therein, characterized in that ion-exchange resins, activated carbon or sawdust are used as porous sorption material, and iron hydroxide, zirconium hydroxide, titanium hydroxide, hydroxide are used as inorganic sorbent. tin (IV) or mixtures thereof [RU 2003108469].

A scientific and technical solution is proposed that relates to methods of water treatment by filtration through granular natural materials and can be used in the domestic and drinking water supply system, including for the production of drinking water of the highest quality category. The method includes filtering water through a layer of granular serpentite with a granule size of 0.15-2 mm and pre-treating the layer of serpentite with an alkaline solution to convert it into an anion exchange material. As an alkaline solution, a solution of sodium, potassium, ammonium or calcium hydroxide, or a solution of sodium or potassium carbonate, or through two or more layers in series, is used. The method provides an increase in the sorption activity of serpentite, expands the range of recoverable contaminants, ensures the supply of high-purity water to the consumer, the compliance with which is achieved directly in the cleaning process without averaging its composition and the need to have a supply of purified water for this while increasing the duration of operation of the granular material loading [RU 2316479 C1].

An invention is described that relates to the field of preparing water for drinking purposes and can be used at water treatment plants, wastewater treatment plants and other public utilities. The contact filter loading contains as the top layer filtering sorption material - flasks, crushed modified grades ODM-2F with a grain size of 2.3-3.5 mm and a density of 1.35 kg / m ³ , as the middle layer - anthracite crushed by grain size 1 , 5-2.3 mm and a density of 1.6 kg / m ³ and the bottom layer is sand with a grain size of 0.7-1.5 mm and a density of 2.6 kg / m ³ . The invention provides for the production of conditioned drinking water with high productivity [RU 2238787 C1].

Closest to the claimed is a method of producing water, which uses a mixture for the neutralization and lithification of household and industrial waste, sediment, sludge and oil-contaminated soils. The mixture for the neutralization and lithification of household and industrial wastes, bottom sediments, sludges and oil-contaminated soils includes aluminosilicate rock, lime and Portland cement and dispersed organic sorbent in the following ratio of components, wt.%:

Aluminosilicate rock - 55-80;

Lime - 5-10;

Portland cement - 10-30;

Dispersed organic sorbent - 5-30.

Peat, wood flour, chaff or sapropel are used as a dispersed organic sorbent [RU 2184095]. This method is taken by us as a prototype.

The disadvantage of this solution is the use of lime, which is easily washed out of the mixture, and therefore its sorption characteristics deteriorate sharply.

We propose a method for producing a sorbent for water purification with raw materials, for the production of which waste from drilling operations in the Caspian Sea are used.

The method of obtaining the sorbent OBR-1

Drilling waste in the form in which it is disposed of at a moisture content of 10 to 60% (dirt) is mixed with an equal amount of Portland cement-500, i.e. in a mass ratio of 1: 1. If the humidity of the mixture is small, then add the appropriate amount of water to obtain a homogeneous concrete mass. The mass is allowed to dry to a state where granules can be formed from it. The mass is dried at a temperature of 25-40 ° C in a stream of air, then leave the material until completely set, which takes 3-4 days. For large volumes of production, steaming with hot steam in chambers for the production of silicate brick or concrete products can be used. Next, the resulting material is kept in running water until the chloride ion test is negative. Granules should have a diameter of 15 to 20 mm.

Drilling waste in the Caspian Sea is a radiation-safe product (there is a sanitary-epidemiological report of the radiation safety supervision department of the Center for Hygiene and Epidemiology in St. Petersburg, protocol No. 1864/06 of 11/01/2006).

The total specific effective activity is 78 ± 10 Bq / kg with a norm of 370 Bq / kg.

The content of the main components in drilling waste (in seized, i.e., after 3-day storage),%: SiO ₂ - 39.88; Al ₂ O ₃ - 7.78; CaCO ₃ - 15.01; H ₂ O - 27.45; salt - up to 10.

However, the waste together with silicon dioxide, kaolin, calcium carbonate and some other oxides also contains a significant amount of sodium chloride, salts of iron, zinc, cadmium, etc. The results of determining the components in the waste are given in Table 1

Table 1 Content of components in drilling waste No. p.p Defined indicators Regulatory content in soils, soils of farmland and materials used in the production of building materials San Pin 2.1.7.573-96 The research results of six samples. The first digit is the smallest, the second is the largest content one. pH of salt extract, units pH 6.0-9.7 8.5-8.8 2. Oil products, mg / kg 10.0 0.50-0.95 3. SAS, mg / kg 5,0 0.05-1.2 four. Chlorides, mg / kg 1500 (for sand) 25000-38000 5. Sulfates, mg / kg 10000 (sand, concrete) 790-950 6. Phosphates, mg / kg Not standardized 10.0-15.0 7. The dry residue after extraction with salt water and evaporation of water, mg / kg 45000-60000 8. Movable iron, mg / kg 10.0 5.0-6.5 9. Zinc mobile, mg / kg No more than 23.0 1.4-2.9 10. Movable Lead, mg / kg No more than 32,0 0.10-0.15 eleven. Movable cadmium, mg / kg No more than 1,0 0.005-0.01 12. Total mercury, mg / kg No more than 2,1 0.003-0.005 13. Movable nickel, mg / kg 1,0 0,035-0,040 fourteen. Movable manganese, mg / kg 2.0 1.0-5.0 fifteen. Arsenic, mc / kg No more than 0,05 0,045-0,050 16. Mobile chromium, mg / kg 0.05 0.01-0.02 17. Movable copper, mg / kg 3.0 0.25-0.35

Hygienic assessment of the sorbent OBR-1 for water purification in the drinking water supply system

Hygienic assessment of the sorbent for water treatment in the drinking water supply system was carried out in accordance with TU 2641-001-51652069-2001, taking into account the guidelines for the hygienic assessment of materials, reagents, equipment, technologies used in the water supply system MU 2.1.4.783. The obtained research results are given in table.2.

table 2 Water quality indicators (water extracts) in a static experiment. Purified tap water with salinity of 200 mg / dm ³ , water temperature - (25 ± 5) ° С, infusion time 1-30 days (1st series of studies), sorbent for water treatment OBR-1 Indicators Hygienic standard Day of observation Right away one 3 5 10 twenty thirty Smell, points ≤2 Try - 0-1 0-1 0-1 0-1 0-1 0-1 The control 0-1 0-1 0-1 0-1 0-1 0-1 0-1 Flavor, points ≤2 Try - 0-1 0-1 0-1 0-1 0-1 0-1 The control 0-1 0-1 0-1 0-1 0-1 0-1 0-1 Color, degrees ≤20 Try - one one one one 0 0 The control 2 one - - 2 2 2 Turbidity 1,5 Try - 0.4 0.3 - 0.15 0.12 0.10 The control <0.1 <0.1 <0.1 - <0.1 <0.1 <0.1 pH, conventional units > 6≤9 Try - 7.6 7.40 7.40 7.40 7.40 7.40 The control 7.5 7.45 7.45 7.45 7.40 7.40 7.40 Permanganate oxidation, mgO ² dm ³ <5 Try 3.9 3.9 3.9 3.9 4.0 4.15 4.15 The control 3.9 3.9 4.0 4.12 4.16 4.16 4.16 Ammonium nitrogen, mg / DM ³ <2 Try - - - - - - 0.96 The control 0.1 - - - - - 0.2 Nitrites, mg / dm ³ <3 Try - - - - - - 0.44 The control 0.1 - - - - - 0,07 Nitrates, mg / DM ³ <45 (50) Try - - - - - - 3.25 The control 1.3 - - - - - 3,5

As can be seen from table 2, the studied material does not impair the organoleptic properties of water (absence of extraneous odor and taste of water extracts, the color value practically did not change in comparison with the control).

Analysis of the content of inorganic impurities in the water extract on the 30th day of the experiment showed (2nd series of studies) that the migration of inorganic substances - toxic metals of hazard class I and II (aluminum, barium, cadmium, nickel, molybdenum, cobalt, vanadium, titanium , niobium, lead) was practically absent, and the migration of metals that affect the organoleptic properties of water (iron, manganese, copper) was not detected (Table 3).

Table 3 The content of inorganic impurities in aqueous extracts from the sorbent OBR-1 for water purification. Distilled water, water temperature (37 ± 2) ° С, infusion time 30 days (2nd series of studies) No. p / p Name of impurities Hygienic standard, mg / dm ³ The concentration of impurities, mg / DM ³ one Aluminum <0.5 0.01 2 Barium <0.1 0.005 3 Chromium <0.05 0.01 four Nickel <0.1 0.001 5 Cadmium <0.001 0.0001 6 Lead <0.03 0.010 7 Arsenic <0.05 0,0005 8 Zinc <3 0,020 9 Calcium <0.5 0.010 10 Magnesium <0.5 0,040 eleven Iron <0.3 0.010 12 Manganese <0.1 (0.5) 0.008 13 Copper <1 0.010

Experimental studies on the effect of the studied samples of the OBR-1 sorbent on the growth and development of microflora were carried out on the specified sorbent, pre-washed thoroughly and filled with dechlorinated tap water after incubation for 24 hours, followed by the introduction of natural microbiocenosis of contaminated water bodies. For control, dechlorinated tap water was also used with the introduction of a natural microbiocenosis of contaminated water bodies. Water samples from a vessel with sorbent and control were investigated according to San Pin 2.1.4.1074-01.

Table 4 The effect of sorbent OBR-1 on the growth of microflora in water Exposition Experience option OKB / 100 cm ³ TKB / 100 cm ³ OMC (37 ° C) 1 hour The control one hundred 105 110 Experience 80 105 90 1 day The control 5,0 0 0.5 · 10 ⁴ Experience 0 0 0.6 · 10 ⁴ 2 days The control 0 0 2.0 · 10 ⁴ Experience 0 0 2.8 · 10 ⁴ 3 days The control 0 0 3,510 ⁴ Experience 0 0 2.0 · 10 ⁴ 20 days The control 0 0 0.5 · 10 ⁴ Experience 0 0 0.710 ⁴ 30 days The control 0 0 0.710 ⁴ Experience 0 0 0.8 · 10 ⁴

As can be seen from the obtained data (Table 4), after one day there is a decrease in the content of microorganisms (common coliform bacteria (OKB), thermo-tolerant coliform bacteria (TKB)) both in the control and in the experiment. An intensive growth of the microbial number (TBC) on the studied sorbent was observed on the third day, and a more significant peak was observed in the experiment, which is also confirmed by data on an increase in the content of ammonium nitrogen in the experiment as compared with the control. On the twentieth and thirtieth days, the natural death of microflora was observed, and the sorbent slowed down the process of dying. The development of microflora on the studied sample during biofouling confirms the feasibility, if necessary, of periodic or permanent disinfection of the water treated on it with one of the generally accepted disinfection methods.

The sorption of various toxicants on the sorbent OBR-1 was studied. Verification of the effectiveness of water treatment with OBR-1 sorbent showed (Table 5) that OBR-1 has a high absorption capacity for toxic metals and organic compounds.

Table 5 The effectiveness of water purification from toxic metals and organic compounds by the sorbent OBR-1 The determined indicator Content, mg / dm ⁵ The cleaning efficiency,% Before sorption After sorption Toxic metals Lead 10.50 0.01 ± 0.005 99.9 Cadmium 6.50 0.006 ± 0.0006 99.9 Zinc 3,50 0.003 ± 0.0003 99.9 Mercury 9.15 0.001 ± 0.00005 99.9 Copper 5,0 0.003 ± 0.0004 99.9 Cobalt 5,0 0.003 ± 0.0004 99.9 Chrome (III) 1,0 0.005 ± 0.0005 99.5 Chrome (IV) 3.0 0.005 ± 0.0005 99.8 Organic pollutants Benzene 5 ± 0.1 0.01 ± 0.005 99.8 Benz (α) pyrene 0.25 ± 0.05 0,00025 99.9 Phenol 1 ± 0.01 0.001 ± 0.0005 99.9 Formaldehyde 1 ± 0.01 0.001 ± 0.0005 99.9 2,4-dichlorophenol 0.5 ± 0.01 0.0005 ± 0.0001 99.9 2,4-dinitrophenol 0.5 ± 0.01 0.0005 ± 0.0001 99.9 Nitrobenzene 0,0005 Not found 99.9

Thus, based on organoleptic, physico-chemical, express toxicological studies, we can conclude that it is possible to obtain environmentally friendly aluminosilicate sorbent OBR-1, designed to purify water from heavy metal ions and a number of organic compounds in the drinking water supply system.

Claims (1)

A method of producing a sorbent for water purification in a drinking water system, characterized in that drilling sludge (OBR) is used as the base of the sorbent, into which Portland cement 500 (PC) is added with a component ratio of 1: 1, formed from the resulting mass granules, from which, after curing at a temperature of 25-40 ° C for 3-4 days, sodium chloride is washed out.