The method of gas purification from hydrogen chloride
(57) Abstract:The invention relates to a method of cleaning gases and can be used for separation of hydrogen chloride (HCl) from various gas mixtures and for removal of HCl gas emissions, such as exhaust gases of the processes of thermal treatment (incineration, pyrolysis) of industrial and household waste. Essence: in the method of cleaning gas from the Hcl adsorption of hydrogen chloride from the gas phase provide a solid adsorbent, and then carry out the regeneration of the adsorbent. As the adsorbent of hydrogen chloride using natural zeolites, the adsorption is carried out at from 20 to 100oC, regenerate the adsorbent by heating to 250-300°C. as adsorbent use natural high-silica zeolites (clinoptilolite, mordenite), dehydrated and neobespechenie, and pre-dictionaraoke and dealuminated also dehydrated and neobespechenie. The technical result of the proposed method of gas purification from hydrogen chloride is to simplify purification technology gas from the Hcl through the use of adsorption of the solid adsorbent and eliminating additional process steps, such as distillation technical hydrochloric acid, and exception obrazovaniya gas purification and can be used for separation of hydrogen chloride (HCl) from various gas mixtures and for removal of HCl gas emissions, for example, flue gas processes thermal treatment (incineration, pyrolysis) of industrial and household waste. The gas mixture and emissions may contain 1-10% (by weight) of hydrogen chloride.To absorb the HCl from the gas mixtures typically use methods adsorption or binding of alkaline reagents. Cleaning gas emissions when recycling is also an introduction to the mixture of different additives, linking the released hydrogen chloride.The known method according to which the furnace for combustion or pyrolysis of chlorinated wastes injected specially synthesized granules on the basis of calcium hydroxide or sodium hydrogen carbonate with the addition of other substances (sodium hydroxide, oxides of magnesium or aluminum). Granular additives absorb the hydrogen chloride and other acid gases emitted at temperatures up to 800oC . The method is not applicable in the processes of high-temperature (>800oC) pyrolysis for gas separation processes, excluding additives in the original environment, for example, in the processes of organic synthesis or distillation of volatile chlorides.Also known methods of gas purification from hydrogen chloride, in which the absorption of HCl by INIA, or water [2, 3, 4]. The absorption of hydrogen chloride is produced by passing a stream of hot gas through the nozzle of calcium carbonate or calcium carbonate-magnesium (dolomite), by bubbling gas through a suspension of calcium hydroxide or calcium hydroxide with additives of calcium carbonate, irrigation flow of gas with a slurry of lime milk or water. The disadvantage of these methods is the formation of unusable waste (sludge, wet pastes or wastewater) containing the chlorides of calcium, magnesium, and other substances and are not subject to discharge into the environment. The disadvantage of the methods is also a multi-stage process to produce a marketable product: for disposal of hydrochloric acid is necessary, in addition to the adsorption process of hydrogen chloride, to the purification and distillation received contaminated HCl solution.The closest the merits of the claimed invention is a method consisting in the adsorption of hydrogen chloride gases from the solid adsorbent and subsequent regeneration of the adsorbent . Prototype method allows you to clean gases from the hydrogen chloride without the formation of unusable waste. The disadvantage of this method is the low selectivity of the solid adsorbent.The technical result is achieved by adsorption of hydrogen chloride from the gas phase solid adsorbent and regenerate the adsorbent. As the adsorbent of hydrogen chloride using natural zeolites, the adsorption is carried out at from 20 to 100oC, regenerate the adsorbent by heating to 250-300oC. as an adsorbent use natural high-silica zeolites (clinoptilolite, mordenite): natural, dehydrated and neobespechenie, and pre-dictionaraoke and dealuminated also dehydrated and neobespechenie.The essence of the proposed method of gas purification from hydrogen chloride is that the absorption of HCl carry out solid adsorbent, which is used as natural zeolite, clinoptilolite or mordenite. For this purpose, the gas is cooled to 20 to 100oC when the regeneration of the adsorbent is passed through the nozzle of the natural zeolite, which is the adsorbent of hydrogen chloride. Regeneration of the adsorbent is conducted by heating up to 250oC and above. For h is t for adsorption and absorption of hydrogen chloride. Released during regeneration of the adsorbent HCl is used to produce hydrochloric acid or used for other purposes. The regenerated adsorbent is used repeatedly (PL. 1).Pre-cooling gas is required in order to increase the adsorption capacity of the zeolite. In Fig. 1 shows the adsorption isotherms HCl high-silica zeolite - clinoptilolite - and low-silicon zeolite - phillipsite at different temperatures. From this figure it follows that the adsorption capacity of highly siliceous zeolites 4-5 times more than the low-silicon zeolites. In addition, the increase in temperature of the adsorption interaction above the 100oC leads to a decrease of adsorption capacity of 3 and more times. The temperature is raised to 250oC leads to the translation of HCl in the gas phase (table. 1, line 5) that is used for the regeneration of the zeolite adsorbent.To increase the absorption capacity of natural zeolite in the hydrogen chloride regenerated adsorbent can be optionally humidified air containing water vapor, or water directly. An even greater increase in the adsorption capacity of the solid adsorbent for hydrogen chloride is achieved in the case of application of PR is of the adsorption capacity of natural, dehydrated and decationizing of clinoptilolite, which show a significant (2-fold) increase in capacity of the zeolite HCl for samples pre-decationizing and delaminating and saturated with water.Example
Through the nozzle, consisting of 1 kg of natural clinoptilolite or pre decationizing and delaminating of clinoptilolite, crushed to a fraction of 0.5 - 3.0 mm, pass gas, consisting of N2, CO2, CO, NH3H2O, containing 6.0 wt.% HCl. Gas through the nozzle miss up to saturation of the sample. After completion of the adsorption process, the zeolite is heated for 10-15 minutes without air to 250-300oC evolved hydrogen chloride is collected. The regenerated and cooled adsorbent used again. Hydration of the adsorbent is achieved directly by passing through the nozzle wet the source gas, or air containing water vapor, or spray water into the layer of the adsorbent.Methods of preparation of the zeolite and the results are shown in table. 3.Technical efficiency of the proposed method of gas purification from hydrogen chloride in comparison with the prototype is to simplify technology clear for example, distillation technical hydrochloric acid, and the exclusion of education unusable waste in the cleaning process.Literature
1. Akira Deguchi. Gasification of wastes generated during the reprocessing of old cars, and the use of gas for electricity generation. - KAGAKU kogaku. in 1991, 55, N 1, S. 37 and 38.2. Patent Of Russia No. 2019275, B 01 D 53/34, 15.09.94.3. Patent Of Russia No. 2095130, 01 D 53/68, 10.11.97.4. Aufarbeitung von Abfallsalzsaure. - Techn. Rdsch. Sulzer. in 1991, 73, N 4, p. 35-38.5. Patent Of Russia No. 2015158, 01 D 53/34, 1994. 1. The method of gas purification from hydrogen chloride, comprising the adsorption of hydrogen chloride from the gas phase solid adsorbent and regeneration of the adsorbent, characterized in that the adsorbent of hydrogen chloride using natural zeolites, the adsorption is carried out at 20 - 100oWith the regenerate the adsorbent by heating to 250 - 300oC.2. The method according to p. 1, characterized in that the adsorbent of the hydrogen chloride used drive high-silicon zeolites, clinoptilolite and mordenite.3. The method according to PP.1 and 2, characterized in that the adsorbent using natural zeolites, dehydrated and neobespechenie.4. The method according to p. 1, wherein eolit, dehydrated and diabetogenic.
FIELD: production of aluminum in cells with self-fired anodes, possibly processes for cleaning anode gases.
SUBSTANCE: method comprises steps of accumulating anode gases, preliminarily combusting them together with air in burner devices mounted in cells; supplying gas-air mixture after preliminary combustion of anode gases along gas duct to stage of dust and gas trapping and blowing out to atmosphere. Before supplying gas-air mixture from burner devices to stage of dust and gas trapping, it is fed to process for oxidizing roasting; heated up to temperature 800-1100°C and then it is cooled until 230-290°C and heat is used for production needs.
EFFECT: lowered content of carbon, resin and CO in exhaust gases.
FIELD: heat technology.
SUBSTANCE: invention relates to technology for treatment of smoke gases from sulfur dioxide. Method for treatment of smoke gases from sulfur dioxide involves passing smoke gases through countercurrent scrubber with absorption liquid based on ammonia aqueous solution for preparing ammonium sulfite followed by oxidation of ammonium sulfite to ammonium sulfate. Then one part of absorption solution removing after oxidation is mixed with fresh ammonium aqueous solution and fed to treatment of smoke gases and another part is fed to utilization. Oxidation is carried out with smoke gases oxygen in indicated scrubber in addition initiating agent for oxidation to absorption liquid as azocompounds. Invention provides simplifying the process and to reduce time for accumulation of ammonium sulfite by 1.8-2.0-fold.
EFFECT: improved method for treatment.
FIELD: gas treatment.
SUBSTANCE: invention relates to novel catalysts, which can be, in particular, used in automobile engine exhaust treatment, in processes of deep oxidation of toxic organic impurities in industrial emission gases, and in other applications. Adsorption-catalytic system, including granules of sorbent capable of sorbing at least one of reagents and catalyst, represents geometrically structured system wherein catalyst is made in the form of microfibers 5-20 μm in diameter, sorbent granules are disposed inside catalyst, and size ratio of sorbent granules to catalyst microfibers is at least 10:1. Catalyst microfibers are structured in the form of woven, knitted, or pressed material. Gas treatment process involving use of such system is based on that gaseous reaction mixture to be treated is passed through above-defined system while periodically varying temperature of mixture, in particular raising it, to accomplish or regeneration of sorbent.
EFFECT: enhanced process simplicity and reliability (simple process government system, absence of mechanical stream switching devices, reduced power consumption, and enabled continuous gas treatment.
2 cl, 2 ex
FIELD: chemical industry; reactor having a circulating fluidized layer and a system of selective catalytic reduction.
SUBSTANCE: the offered invention is pertaining to the field of chemical industry. A combination of a device consisting of a reactor or a combustion chamber with a circulating fluidized layer and a selective catalytic reduction system contains the reactor chamber with a circulating fluidized layer, the primary solid particles separator, a means for return of the solid particles trapped by the primary solid particles separator to the reactor chamber, at least one surface of heat transfer of a vapor overheater or an intermediate vapor overheater, a system of the selective catalytic reduction, a dry scrubber located below on the production chain in respect to the system of the selective catalytic reduction and a means for introduction of ammonia in the flow of a smoke gas-solid particles. According to one of the offered versions the given device contains a multicyclone dust separator and a means for return of the solid particles trapped by the multicyclone dust separator to the reactor chamber. The given engineering solution ensures low outbursts of nitrogen oxides at the minimum operational cost.
EFFECT: the invention ensures low outbursts of nitrogen oxides at the minimum operational cost.
11 cl, 3 dwg, 2 tbl
FIELD: consuming industrial waste.
SUBSTANCE: method comprises securing the housing filled with the charge of the solid rocket fuel to the front part of the gas duct of the plant for using the charges of the solid rocket fuel, burning the solid rocket fuel, and processing the combustion products by cooling the combustion products with a material with high heat capacity, dry cleaning of gas with a neutralizer-sorbent, and afterburning the combustion products.
EFFECT: enhanced efficiency.
7 cl, 2 dwg
FIELD: purification of gases.
SUBSTANCE: method comprises absorbing sulfur dioxide by means of a lime suspension, crystallization, and removing slime. The gas is cooled before absorbing up to the dew point by water evaporating. The ratio of the volume of water to that of the gas should be 0.08-0.12 l/m3. The water temperature exceeds that of the dew point by 10°C of the cooled gas. The gas is absorbed by the suspension made of droplets supplied perpendicular to the gas flow.
EFFECT: enhanced quality of purification.
1 cl, 1 dwg, 1 tbl
SUBSTANCE: device comprises inlet and outlet for gas and plate provided with openings and interposed between the gas inlet and outlet for permitting gas to flow from below. The top side of the plate is used for flowing the absorbing liquid. The inlet pipeline connects the tank with the absorbing liquid to the top of the plate. The pump transports the absorbing liquid from the tanks to the top of the plate through the inlet pipeline and over the plate. The device is additionally provided with the outlet vessel for collecting the absorbing liquid that flows over the plate with openings and at least with one means for distributing that is in a contact with the gas supplied to the device through the inlet. The liquid flows from the outlet vessel to the tank upstream of the site where gas flows through the plate with openings.
EFFECT: enhanced reliability.
16 cl, 10 dwg, 1 ex
FIELD: environment protection from radionuclides.
SUBSTANCE: proposed method for producing chemical sorbent to absorb nuclear fuel fission products (radionuclides of iodine, ruthenium, and their volatiles) includes impregnation of activated carbon in triethylene diamine followed by its drying at temperature of 110-130 °C. For the purpose use is made of activated carbon produced from raw bituminous coal having micropore volume vmp = 0.28-0.33 cm3/g and total pore volume vΣ = 0.85-1.0 cm3/g. Activated carbon is impregnated until triethylene diamine content is reduced to 1-2% of base mass. Then chemical sorbent obtained in the process is dried out and sifted.
EFFECT: enhanced quality of chemical sorbent obtained.
1 cl, 1 tbl, 9 ex
FIELD: chemical industry; petrochemical industry; gaseous industry; oil-producing industry; oil-processing industry; installation for purification of the hydrocarbon raw from methanol.
SUBSTANCE: the invention is pertaining to the technology of purification of the hydrocarbon raw from methanol and may be used in gaseous, petroleum, petrochemical and chemical industries. The installation includes the assembly of the preliminary separation of the raw connected with the block of the adsorbing purification, the pipeline links and the shut-off-adjusting fittings. The assembly of the preliminary separation includes: the block of the preheating of the raw consisting of the heat exchangers (1) and (2), the rectifying column (3) with the connecting pipes for feeding of the liquid hydrocarbon raw (4), withdrawal of the methanol with the light fraction of hydrocarbons (5) and the withdrawal of the hydrocarbon tailings (6) with the bottom heating, the cooler (10) and container(11). The block of the raw preheating is connected to the connecting pipe (4) of the raw feeding into the rectifying column (3), and the connecting pipe (5) for the raw withdrawal in series through the raw preheating block, the cooler (10) and the container (11) directly connected with the block of adsorbing purification. In the other version the block of the raw preheating is connected to the connecting pipe (4) of feeding of the liquid hydrocarbon raw into the rectifying column (3), and the connecting pipe (5) of withdrawal through the heat exchanger (1) and the cooler (10) is connected to the connecting pipe (23) of the inlet into the extraction column. The connecting pipe (25) of withdrawal of the methanol with the light fraction of hydrocarbons out of the extraction column (20) is connected to the inlet connection pipe (28) of the separator (21), and the connecting pipe (26) of withdrawal of the water-methanol mixture is connected with the intermediate container (22). The connecting pipe (29) of withdrawal of the methanol with the light hydrocarbons from the separator (21) is connected to the block of the adsorbing purification. The connecting pipe (29) of withdrawal of the water-methanol mixture of the separator (21) is connected to the intermediate vessel (22), which outlet is connected to the feeding line of the extracting liquid into the extraction column (20). The invention reduces the operational costs, increases the lifetime of zeolite.
EFFECT: the invention ensures reduction of the operational costs, the increased lifetime of zeolite.
2 cl, 2 dwg, 2 ex
FIELD: chemical industry; oil-refining industry; other industries; methods of production of the catalytic microporous fine-dispersed materials.
SUBSTANCE: the invention is pertaining to the method of production of the catalytic microporous fine-dispersed material, which is used in such processes, as purification of the oil fractions, purification of the sewage disposal, the catalytic conversion of the exhaust gases exiting from the combustion engines. The method allows to produce the catalytic microporous fine-dispersed material with the coating of the rare-earth metal oxide, in which the quantity of the metal oxide deposited on it is high without the risk for efficiency of the material. At that the rare-metal oxide is deposited on the outer surfaces of the indicated material and may be within the interval of 20-70 mass % with respect to with respect to the total equivalent content of the rare-earth metal oxide and the microporous fine-dispersed material. The method provides for the combination of the quantity of the colloid dispersion of the hydrate of the rare-earth metal oxide with the compatible microporous fine-dispersed material with formation of the suspension and the thermal treatment of the indicated suspension for the rare-earth metal oxide fixation on the outer surfaces of the indicated material. At that the indicated microporous fine-dispersed material has the average size of the pores less than 20 Å, and the indicated colloid dispersion has the particle size of the particles of not less than 20 Å. The invention also presents the catalytic free-loose fine-dispersed material with the rare-earth metal oxide coating containing the ceolite fine-dispersed material, the rare-earth metal oxide. At that the indicated ceolite fine-dispersed material has the average size of the pores less than the size of the particles of the indicated rare-earth metal oxide, and more than 20 mass % of the indicated rare-earth metal oxide is on the outer surfaces the indicated ceolite fine-dispersed material with respect to the total equivalent content of the rare-earth metal oxide and the ceolite. The ceolite free-loose fine-dispersed material having the high contents of the rare-earth metal oxide has the tendency to be the very stable material.
EFFECT: the invention ensures production of the catalytic microporous fine-dispersed material with the coating of the rare-earth metal oxide without the risk for efficiency of the material and the ceolite free-loose fine-dispersed material having the high contents of the rare-earth metal oxide has the tendency to be the very stable material.
31 cl, 11 ex, 3 tbl