Demercurisation composition

FIELD: metallurgy.

SUBSTANCE: proposed composition comprises 3.0-5.0 wt % of dichlorisocyanuric acid soda as halogen-bearing compound, 0.5-1.5 wt % of thiourea as complexing agent and water making the rest.

EFFECT: higher efficiency of removal mercury from soil, reduced aggressiveness of used substances relative to rooms interior, instruments and equipment.

1 tbl

 

The invention relates to compositions intended for the purification of mercury (mercury removal) of various objects, in particular residential and administrative buildings, health institutions, schools, preschools, mercury pollution which is caused by the destruction of household mercury-containing products.

From the prior art known composition for demercurization, comprising an aqueous solution of potassium permanganate and hydrochloric acid. The reaction products of mercury and demerkurizatsiju reagent removes detergents (see Pugacheva P.P. "Working with mercury in laboratory conditions", M., Izd-vo "Chemistry", 1972). However, the composition is not sufficiently effective, because its application does not provide a decrease in the concentration of mercury vapor in air to the maximum permissible concentration (MPC) - 0.0003 mg/mł

Known composition for demercurization of premises-based solutions of copper sulfate and potassium iodide (patent RU №2081198, M CL SW 43/00, 1997). The peculiarity of this structure is that its active components are formed directly on the cleaned surfaces by sequential sputtering first solution of copper sulphate, and then potassium iodide solution, which interact with the mercury with the formation of complex compounds. The disadvantage of this structure is the toxicity of agressivnosti formed by the reaction of gaseous iodine and as a consequence, damage to the interior (education brown plaque), corrosion of metal products, negative effects on devices and equipment. Work on demercurization using this composition, due to the high aggressiveness components must perform a special service.

The closest to the technical essence of the present invention is a composition for cleaning of premises from mercury on the basis of an aqueous solution of alkali metal halide. As the halide of the alkali metal in the known method using sodium chloride, acidic solution (pH 1.5 to 2.5) which receive unipolar treatment (electrolysis) immediately before use (avts USSR 1157103, CL C22B 43/00, 1983).

The disadvantage of this structure is the considerable complexity of the cleaning process from mercury (the need to subject the composition of the electrolysis before performing the demercurization), which does not allow to recommend this part to address mercury contamination in the domestic environment.

The objective of the invention is the creation of demercurization of the composition, with which users of household mercury-containing products, in case of their failure, can own, without calling a special service, to eliminate mercury pollution with a guaranteed assurance of installed sanitary-and-hygienic norms.

Technical result achieved in the present invention represents an increase of efficiency of purification of mercury and the aggressiveness of the drugs used in relation to interiors, appliances, equipment.

The solution of the stated problem and the achievement of a specific result is achieved by the fact that the composition for demercurization of objects contaminated with mercury, including halogen-containing compound and water, according to the invention further comprises complexing agents, which is used as a thiourea, as well as halogenated compounds using sodium salt of dichloroisocyanuric acid, in the following ratio, wt.%:

Sodium salt of dichloroisocyanuric acid3,0-5,0
Thiourea0.5 to 1.5
WaterRest

The use of the composition improves the efficiency of mercury removal - reduces the content of mercury vapor in the air to the amount not exceeding the maximum permissible concentration (MPC=6,0003 mg/cubic meter), while reducing the aggressiveness of the drugs used in relation to Dept the major materials appliances and equipment.

Demercurization composition prepared by dissolving the components in water at the above ratio.

The components of the composition under the conditions of application of sustainable, non-toxic. Processing contaminated with mercury surface specified by the simple in technological performance, easy and does not require a long time to run.

Demercurization is carried out by treating the floor with an aqueous solution of chemicals, ensuring the translation of atomic mercury (mercury vapour and mercury adsorbed by the surface of the floor) mercury compounds. Demercurization ends by wiping surfaces with cloths dampened with household detergents. Wipes contaminated with salts of mercury, are removed by neutralization to a specialized company.

The mechanism of action of the composition is schematically represented as follows.

When interacting with water the sodium salt of dichloroisocyanuric acid (this salt contains latent form a strong oxidizer) is activated, forming hypochlorous acid, which then dissociates in water to form hypochlorite ion and hydrogen ion:

In fact, an active substance is hypochlorous acid. The maximum activity of lamovita acid gets in weakly acidic solutions. Therefore, it is important to maintain a stable pH level in the range of 5.8 to 6.2. This effect is high and stable demercurization activity of the claimed composition is achieved by the introduction in addition to the basic acting substance (sodium salt of dichloroisocyanuric acid) supplements in the form of thiourea. Hypochlorous acid under these conditions does not decompose with the formation of chlorine is in the bound state, thus is safer for people and the environment and does not require special safety measures.

Molecular structure of timeonline may be represented by the canonical thioamide form and toiminimi forms bearing the negative charge on the sulfur atom and the positive on the nitrogen atoms amidnogo fragment:

As a result, the sulfur atom is a strong nucleophilic center and thiourea is protonated at the sulfur atom with the formation of salt:

In the above reactions in solution are formed active oxidation components, namely HClO, ClO-that translate mercury atomic ion condition:

Hg+2HOCl→HgCl2+H2O

Data on the efficacy of the composition under different ratio of ingredients shown in the table.

Composition for removing mercury pollution caused by the destruction of household mercury-containing products
№ p/pConcentration, wt.%The content of mercury vapor in air, mg/m3(MPC=0.0003 mg/m3)
Sodium salt of dichloroisocyanuric acidThioureaWater
1,1,001,7097,300,0015
2.2,001,0097,000,0007
3.3,000,5096,50<0,0003
4.4,000,3095,70<0,0003
5.5,001,5093,50<0,0003
6.6,001,7092,30<0,0003

As the table shows, the use of the composition containing the optimal number of components that best provides for the cleanup of mercury to the established norms, i.e. when processing premises demercurization composition at a content of sodium salt of dichloroisocyanuric acid in the range of 3.0 to 5.0 wt.% and thiourea in the range of 0.5-1.5 wt.% reduced mercury vapor in the air to values not exceeding the maximum allowable value (MPC=0.0003 mg/cu.m). The decrease in the concentration of the components reduces the efficiency of mercury removal (items 1,2), increasing the concentration does not change the final result.

Composition for demercurization of objects contaminated with mercury, including halogen-containing compound and water, characterized in that it further comprises complexing agents, which is used as a thiourea, as well as halogenated compounds using sodium salt of dichloroisocyanuric acid, in the following ratio, wt.%:

Sodium salt of dichloroisocyanuric acid3,0-5,0
0.5 to 1.5
WaterRest



 

Same patents:

FIELD: metallurgy.

SUBSTANCE: proposed method comprises anodic oxidation of melt in acid electrolyte at application of electric current. Note here that said anodic oxidation is carried out in acid electrolyte containing 150 g/l of H2SO4+50 g/l HCl. Applied direct electric current features density of 250-300 mA/cm2. Application of said current is conducted at 20-40°C.

EFFECT: notable increase in anodic oxidation rate.

3 tbl, 2 ex

FIELD: metallurgy.

SUBSTANCE: proposed method comprises thermal treatment of residues in air whereat temperature is increased to, at least 500°C at the rate of 150 °/h and curing at said temperature for, at least, two hours. Treated residues are mixed with aluminium powder resulted from grinding aluminium chips and are subjected to aluminothermy with subsequent separation of formed alloy and slag. Aluminothermy is conducted in tight reactor with continuous discharge of gaseous and sublimate reaction products. Note here that aluminium powder and thermally treated residues are taken at the ratio of 1: 6.5-7.0).

EFFECT: higher efficience of processing galvanic process copper bearing residues, method simplifying and higher ecological safety.

3 dwg, 2 tbl, 2 ex

FIELD: metallurgy.

SUBSTANCE: proposed method comprises blending the wastes with flux, smelting the blend, dividing melting products into slag and alloy containing copper and platinum metals. Sodium hydroxide is used as flux. Blending is carried out with copper at copper content of 80-30 wt %, flux content of 10-35 wt % and content of wastes of 10-35 wt %. Melting is conducted at 1100-1200°C for 10-20 min. Produced alloy is electrochemically dissolved in copper sulphate solution. Slag obtained in electrochemical dissolution contains platinum metals and is processed in sulfuric acid solution to remove impurities.

EFFECT: higher yield of platinum metals.

2 ex

FIELD: metallurgy.

SUBSTANCE: arc-furnace dust is agglomerated together with crushed carbon reducing agent and binder material in the form of pellets. The latter are dried, heated and roasted in rotary kiln together with solid reducing agent lumps at temperature of discharged materials of 700-1000°C, gases are cooled and dust bearing zinc and lead sublimates is caught therefrom. Note here that, prior to agglomeration, arc-furnace dust is premixed with lime-bearing material and crushed carbon reducing agent in amount 1.5-2 times higher than stoichiometrically necessary content of carbon for reduction of iron, zinc and lead oxides. Mix is damped to water content of 8-11% and cured for 1-3 hours while obtained pellets are loaded into kiln together with solid carbon reducing agent lumps in amount of 200-500 kg per ton of arc-furnace dust, reducing agent lump size making 20 mm.

EFFECT: higher yield of zinc and iron metallisation.

4 cl, 2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: solid or melted substances are loaded on graphite body heated, at least, partially, inductively. Reducing agents are introduced therein, other than graphite carbon to collect flowing reduced and/or gasified melt. Note here that reducing agents are introduced along with solid or melted loaded particles. Said reducing agents represent natural gas, coal dust, brown coal dust, hydrocarbons, hydrogen, carbon oxide and/or ammonia to be introduced together with steam, oxygen, carbon dioxide and/or halogens or halogen hydrides.

EFFECT: simplified process.

18 cl, 5 dwg

FIELD: metallurgy.

SUBSTANCE: proposed method comprises smelting initial material to produce vitreous arsenic trisulfide. Arsenic-bearing sulfide cake is subjected to neutralisation given its moisture content does not exceed 0.5%. Smelting is performed in protective capsule preformed from liquid dump slag at 350-400°C using the heat of said dump slag. Then, buffer layer of heat-insulation material is formed on the surface of obtained cake melt. Now, said protective capsule is sealed by coating its surface with buffer layer of liquid dump slag to be hardened thereafter. Aforesaid heat-insulation layer represents crushed slag and/or quartz sand and/or undersized crushed stone.

EFFECT: higher efficiency.

2 cl, 1 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: proposed furnace comprises body arranged at welded frame and composed of refractory outer lateral, front and rear end walls, accumulation wall and inclined platform confined by hearth and walls, crown, working and spare drain notches, working and slag opening shutters, rotary bowl and gas duct. Furnace has outer heat insulation of walls consisting of asbestos grit, dual layer of refractory mats and dual layer of asbestos cardboard sheets. Accumulation bath and inclined platform are made from corundum blocks laid on the layers of asbestos cardboard and light brick. Furnace frame is filled with concrete with filler from fireclay and asbestos grit. Crown above inclined platform and bath has heat-insulation plaster above which dual layer of refractory heat-insulation mats is laid. One lateral wall of the furnace if provided with two injection eight-mixer medium-pressure burners directed at angle to inclined platform while another lateral wall is furnished with on injection eight-mixer burner directed at angle to inclined platform and another 17-mixer reheat chamber directed to furnace hearth lined by refractory bricks to house sin-mixed gas injection burner, air blower, and waste gas heater arranged above said chamber. Notches in lateral wall for release of fused metal are made in fast-replace notch bricks.

EFFECT: higher efficiency, reduced heat losses.

7 cl, 10 dwg

FIELD: heating.

SUBSTANCE: furnace includes a housing formed with side, front and rear external end refractory walls, a storage bath that is restricted with a bottom and walls, an inclined platform, an arch, a drain tap-hole and a gas duct. The housing is arranged on a welded concrete-cast frame with filler from diatomite chips and provided with two heat-insulating layers from light brick and asbestos board plates under the bottom, two heat-insulating layers from light brick and four layers of asbestos board plates under the inclined platform. The storage bath and the inclined platform are made of mullite-corundum blocks MKP-72 laid on three layers of asbestos board and have packing from diatomite chips, which are mixed with crushed asbestos chips. The furnace has lower and upper large arches located one above another so that a gap for a flue gas duct is formed between them. The furnace is equipped with a rotating chute having the possibility of being turned during liquid metal pouring and having an intermediate nose, a rotating bowl with a shaft welded in its lower part, the end of which is pressed into an inner shell of a ball bearing, and its outer shell is fixed in a bracket fixed in the rear wall of the furnace; at that, a long pouring nose with two handles is welded to the turning bowl for series pouring of metal molten in the furnace to the pouring equipment located in the service sector at an angle of 140°. Front wall of the furnace is provided with a row of injection burners of intermediate pressure, out of which two eight-mixer burners with long flame are directed on edges to the charge contained on the inclined platform and to the bath with molten metal, one burner BIGm 2-6 and two burners BIGm 2-12 are directed to the charge.

EFFECT: high furnace capacity, reduction of heat losses and melting loss and possible environmentally safe remelting of aluminium scraps.

7 cl, 5 dwg

FIELD: metallurgy.

SUBSTANCE: method involves cleaning of scraps by acid treatment with removal of manganese dioxide. Then, deoxidation of cleaned scraps, its hydration, grinding, dehydration at increased temperature is performed so that tantalum hydride powder is agglomerated and tantalum capacitor powder is obtained. At that, acid treatment is performed at room temperature using the solution containing 100-300 g/l of sulphuric acid and 110-300 g/l of hydrogen dioxide, or the solution containing 30-150 g/l of hydrochloric acid and 75-225 g/l of hydrogen dioxide. Scrap hydration is performed by treatment using the solution of hydrofluoric acid with concentration of 1-5%. The obtained capacitor tantalum powder provides specific charge of up to 7300 mcC/g, breakdown voltage of more than 200 V and leakage current of 0.0001-0.0003 mcA/mcC when being used in anodes of tantalum oxide-semiconductor capacitors.

EFFECT: reduction of energy intensity and improvement of environmental friendliness of the process at its simultaneous simplification.

3 cl, 6 ex

FIELD: process engineering.

SUBSTANCE: invention relates to flotation of man-made stock. Method of flotation of sulfide ores of nonferrous and noble metals comprises conditioning crushed ore with dithiophosphate solution or other sulfhydric collectors in lime medium and flotation. Note here that for reduction in floatability of pyrite and increase in extraction of metal up to 10 wt % of thiourea ((NH2)2CO) or its derivatives are preliminary introduced in the solution of dithiophosphate as a modifying agent. Then, pulp from ore is conditioned, first, with modified dithiophosphate at pH 8.5-9.0 for 3-5 minutes and, then, with, xanthate at pH over 9.0 for 1.0 minute. Then flotation of sulphides of nonferrous metals and mineral forms of noble metals at input of modified of dithiophosphate and xanthate varying from 1:3 to 3:1, respectively.

EFFECT: reduced floatability of pyrite and other iron sulphides, increased floatability of nonferrous metal minerals, native gold particles and its exposed concretions with sulphides.

3 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: method involves breaking down said lamps and devices, grinding, heating, evacuating the scrap lamps in a chamber and subsequent condensation of mercury vapour in cooled traps with successive sealing of all processes, wherein a batch of lamps and devices is broken down right away; grinding is carried out to particle size of not more than 20 mm, destruction and extraction of mercury is carried out at temperature of 150-200°C and a vacuum of up to 10 Pa and holding for 30 minutes; a second step for cleaning the scrap with a washing liquid (1 N sulphuric acid or hydrochloric acid solution) is carried out, followed by separation of sockets and scrap glass. When filling the chamber with scrap lamps with washing liquid, circulation mixing is carried out for at least 5 minutes. After separating from the scrap, the washing liquid is subjected to filtration and thermal decomposition to metallic mercury at temperature higher than 500°C. Separation of cleaned sockets and scrap glass is carried out by sieving through a sieve with different cell size under vibration action.

EFFECT: high efficiency and environmental friendliness of the process, efficiency of extracting mercury while reducing power consumption.

5 cl, 6 ex

FIELD: machine building.

SUBSTANCE: plant includes two units, the first one of which is a lamp sorting unit, and the second one is a unit of multistage exit gas cleaning system. The first unit includes a lamp sorting device consisting of a loading assembly, a pneumatic vibrating separator with a crusher and a cyclone, a crushed lamp glass collecting hopper, a lamp base receiving container and a fluorescent dye container. The second unit is made in the form of multistage exit gas cleaning system consisting of a sleeve filter, adsorbers, a gas blower with a compressor, which creates negative pressure in the plant of 5-8 kPa in the lamp loading zone and up to 19-23 kPa before gas blower. The plant is equipped with a series pulverised-coal and gas emission cleaning system consisting of a cyclone, sleeve filters, a working adsorber operating on activated coal, which allows reducing mercury content in exit gases to the level of less than 0.0001 mg/m3.

EFFECT: improving utilisation efficiency owing to excluding the probability of PC-air emissions to a production room and improving energy resource saving of metal scrap processing and gas cleaning.

2 cl, 2 dwg

FIELD: metallurgy.

SUBSTANCE: method for gold extraction from cyanide solutions with dissolved mercury contained in them, gold-bearing ores formed during leaching, involves sorption of gold and mercury on activated carbon with enrichment of activated carbon with gold and mercury. Then, gold desorption is performed with alkali-cyanide solution under autoclave conditions, gold electrolysis from strippants so that cathode deposit is obtained and its remelting is performed so that finished products are obtained in the form of raw base gold alloy. Prior to gold desorption the selective desorption of mercury is performed by treatment of saturated carbon with alkali-cyanide solution containing 15-20 g/l of sodium cyanide and 3-5 g/l of sodium hydroxide, at temperature of 18-20°C and atmospheric pressure during 10 hours.

EFFECT: simplifying the method due to mercury desorption in a separate cycle prior to gold desorption; improving selectivity of gold extraction and creation of possibility of safer conditions during processing of cathode deposits so that finished products are obtained.

4 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: method of gold extraction from mercury-containing cyanic solutions consists in sorption by ion-exchange resin of AM-2B mark. Then mercury de-sorption is carried out from saturated ion-exchange resin at a temperature 40-50°C and for 6 hours and aurum de-sorption. Note that mercury de-sorption is done by solution containing sulfuric acid 30-50 g/l with the presence of hydrogen peroxide 5-10 g/l.

EFFECT: reduction of mercury content in saturated gold-containing ion-exchange resin till safe concentration or complete elimination of mercury penetration into finished products.

5 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: apparatus contains a unit for crushing fluorescent lamps and a decontamination unit. The crushing unit is in form of a drum with revolving blades for crushing the glass of the lamps, a conveyor and a tray for feeding glass into the decontamination unit. The decontamination unit is in form of a mixer for a demercuration solution and the processing milling agent, which is mounted on a base with possibility of being rotated by a drive and tipping over in order to unload the processed product, a container for collecting the processed product which is mounted on a movable tray with a gutter for draining the spent solution, and a receiving tank from which spent solution can be pumped through a filter with a sulphonated carbon KU-2 filling and then taken for burning in a furnace to obtain mercury metal. The demercuration solution contains potassium permanganate KMnO4 - 0.0002525 g/l, hydrochloric acid HCl -0.000125 g/l and process water - 0.0375 g/l for one recycled fluorescent lamp. Said solution is at 28°C.

EFFECT: high efficiency and energy-saving when processing fluorescent lamps and purifying gases.

1 dwg

FIELD: machine building.

SUBSTANCE: procedure for extraction of mercury form fluorescent lamps consists in lamps crushing, in loading scrap into container and in removal of mercury from lamps scrap in bath with solution during 1.5 hour. Further, the container is set on a tray for solution drainage. Scrap and accessories in containers are transported to a classification line. Spent solution is collected into a receiving tank and pumped over through a filter with a sulphonated coal. The filter with sulphonated coal is burned and there is produced metal mercury. Solution is collected for repeated preparation or for draining into sewage.

EFFECT: raised efficiency and energy saving at scrap processing and at gas cleaning.

1 dwg, 1 tbl

FIELD: metallurgy.

SUBSTANCE: procedure for extraction of mercury out of mercury-selenium final tailings consists in introduction of mercury selenium final tailings into pulp of calcium hydroxide and in re-pulping produced mixture, in burning in tubular furnace and in withdrawing process gases of burning containing vapours of mercury into condenser, in condensing mercury out of process gases, in production of stupp and in removing mercury from stupp. Also, mixture re-pulping is performed at ratio of hydroxide of calcium and selenium in final tailings Ca(OH)2:Se final tailings=(3.0-3.5):1. First, there is burned re-pulped mixture producing process gases not containing elementary selenium, further there is burned stupp upon its removal. Burning is carried out in a rotating tubular furnace at excess of oxygen. Output of mercury comes to 99 %. There is produced mercury-less ash with maximal content of bound selenium suitable for successive extraction of selenium.

EFFECT: increased output of mercury facilitating further extraction of selenium due to elimination of mercury losses owing to complete selenium binding with excess of calcium hydroxide at oxidising burning.

1 ex

FIELD: metallurgy.

SUBSTANCE: procedure consists in combustion of spent catalyst of acetylene hydro-chlorination in air and in successive cooling combustion products for condensation and extraction of metal mercury and for neutralisation of fumes. Neutralisation is performed with solution of alkali producing water-salt solution with mercury oxide. Mercury oxide produced in the process of neutralisation is filtered from water-salt solution. Further, mercury oxide is directed to recycle and mixed with source spent catalyst for successive decomposition releasing metal mercury at combustion of spent catalyst.

EFFECT: increased output of metal mercury from spent catalyst of acetylene hydro-chlorination.

2 cl, 2 tbl, 1 dwg, 7 ex

FIELD: metallurgy.

SUBSTANCE: proposed method comprises decomposing wastes in electrolyte solution containing sulphuric acid and hydrogen dioxide. Note here that redox potential varies from initial potential of thallic amalgam of -0.35 V to that of mercury of +0.69 V to produce pure mercury and saturated electrolyte. Note here that saturated electrolyte is in equilibrium with univalent thallium sulphate precipitate that is extracted by filtration and used as finished high-purity chemical reagent.

EFFECT: high process rate, better ecology.

1 ex

FIELD: chemistry.

SUBSTANCE: method involves treatment of wastes with a calcium polysulphide solution. Before treatment with the calcium polysulphide solution, the wastes are mixed with an oxidising agent which contains active chlorine in amount of 0.15-10.0 % of the weight of the wastes. Water is then added and the mixture is held. The obtained mixture is treated with a calcium polysulphide solution in ratio of calcium polysulphide solution to the mixture equal to 1-4:10 wt % respectively, and the reaction mixture is then held.

EFFECT: avoiding the need to use complex equipment, recycled wastes which are converted from hazard class 1 to hazard class 4 contain mercury sulphide inclusions which are not hazardous to the environment and are safe for disposal.

5 cl, 1 tbl, 9 ex

FIELD: utilization of mercury-containing devices; processing rejected luminescent lamps and mercury-containing devices and devices whose service life has expired.

SUBSTANCE: plant for utilization of mercury-containing devices includes working bath, unit for breaking and treating the mercury-containing devices with liquid medium which is made in form of container with breaking devices and devices for supply of liquid medium, vibrator, working solution reservoir connected with breaking device by means of drainage pipe line laid in lowest point of working bath; plant is also provided with pipe lines equipped with fittings and pump for transfer of liquids; it is also provided with water reservoir which is connected with breaking device by means of drainage pipe line laid at definite height above bottom of working bath; working bath, water reservoir and working solution reservoir are combined in system which makes it possible to fill working bath in turn with water or with working solution by means of one pump; breaking device is made in form of cross-piece with knives secured on it. Proposed method of utilization of mercury-containing devices includes grinding of such devices under layer of water at continuous washing of luminescent substance, forming the suspension and settling mercury in form of finely-dispersed particles on bath bottom, after which mercury is subjected to neutralization with the aid of said plant. Breaking the mercury-containing devices and washing-off the luminescent substance will be performed by vibration; neutralization is accompanied by forming of insoluble calomel.

EFFECT: possibility of performing chemical demercuration at temperature close to surrounding temperature.

3 cl, 5 dwg

Up!