29 results about "Calcium bicarbonate" patented technology

The invention discloses a composite mineral admixture prepared from heat-stewed steel slag and a preparation method of the composite mineral admixture, and the mineral admixture is prepared from the following raw materials in parts by weight: 40-50 parts of heat-stewed steel slag powder, 20-30 parts of granulated blast furnace slag powder, 20-40 parts of fly ash, 0.01-0.1 part of a grinding aid and 0.5-4.0 parts of an exciting agent, wherein the grinding aid comprises glycerol and diethanol isopropanolamine, and the exciting agent comprises diphenyl phosphate, sodium sulfate and ammonium bicarbonate. The preparation method comprises the following steps: mixing calcium bicarbonate and water, spraying the mixture on high-temperature steel slag at 600-800 DEG C, carrying out hot braising under the condition of steam pressure of 0.2-0.5 MPa for 8-12 hours to pulverize the steel slag until the particle size is less than 5-10 mm, and carrying out vertical milling on the pulverized steel slag and a grinding aid for 20-40 minutes to obtain hot-braised steel slag powder; uniformly mixing the heat-stewed steel slag powder, granulated blast-furnace slag powder, fly ash, a grinding aid and an exciting agent in proportion to obtain mixed powder; and finally, grinding the mixed powder for 30-50 minutes by adopting a high-energy planetary ball mill to obtain the cement concrete composite mineral admixture with the specific surface area being greater than or equal to 600m < 2 > / kg. According to the invention, the potential hazard of poor stability of a cement concrete material caused by high f-MgO content in the steel slag is broken through, the steel slag is efficiently utilized to prepare a low-carbon green building material, a composite mineral admixture is developed, and the performance meets the II type requirement in JG / T 486-2015 Composite Admixture for Concrete.

This invention discloses a denitrification agent for low-temperature denitrification and its preparation method, belonging to the field of denitrification technology. The denitrification agent is prepared using diatomaceous earth as the matrix framework, compounded with calcium chloride, calcium bicarbonate, chitosan, sodium lignosulfonate, and TRIS (tris(hydroxymethyl)aminomethane). The components synergistically optimize the pore structure. Chitosan and sodium lignosulfonate achieve self-assembly through hydrogen bonding and electrostatic attraction. Nitrogen oxides are removed through a dual action of alkaline absorption and electrostatic adsorption. The TRIS can be regenerated and reused after alkali washing. This invention's denitrification agent solves the problems of high reaction temperature, poor low-temperature activity, low efficiency in removing low-concentration nitrogen oxides, and easy ammonia escape in traditional SCR denitrification technology, and can meet the requirements for NO removal in flue gas from power plants. x ≤15mg / m 3 It has ultra-low emission indicators, and features excellent low-temperature activity, high denitrification efficiency, and recyclability. It is suitable for denitrification treatment of low-temperature flue gas in power plants, etc.

This invention relates to the field of non-fired brick preparation technology, specifically disclosing a method for preparing non-fired bricks with recycled concrete aggregate for thermal insulation. The method includes the following steps: (1) Immersing the recycled concrete coarse aggregate in a saturated calcium bicarbonate solution, then removing and drying the coarse aggregate to obtain pretreated coarse aggregate. (2) Taking the following raw materials: 45-62 parts by weight of slag powder, 18-25 parts by weight of silicate cement, 6-10 parts by weight of fly ash cenospheres, 30-40 parts by weight of the pretreated coarse aggregate, 55-70 parts by weight of sand, and 1-2 parts by weight of water-reducing agent. The above raw materials are mixed evenly, and then mixing water is added according to a water-cement ratio of 0.18-0.22. After mixing, the resulting brick is pressed into a blank and naturally cured to obtain non-fired bricks. The method of this invention can effectively reduce the adverse effects of recycled concrete aggregate on the mechanical properties of non-fired bricks, and the non-fired bricks prepared by this invention also have good thermal insulation properties.

The application provides a ship exhaust carbon dioxide capture system and method, which comprises the following: an exhaust pretreatment unit, which comprises at least an engine, an exhaust pretreatment tower and a fan; the exhaust port of the engine is connected to the air inlet of the exhaust pretreatment tower; the air outlet of the exhaust pretreatment tower is connected to a CO2 absorption unit through the fan; the liquid outlet of the exhaust pretreatment tower is connected to a solution dilution unit; the CO2 absorption unit comprises at least a first absorption tower and a first dissolving tank; the first absorption tower is connected to the first dissolving tank; the first dissolving tank is provided with a first stirrer; the first dissolving tank is further connected to a first calcium carbonate filling unit; the solution dilution unit comprises at least a ballast water tank and a solution dilution tank; the ballast water tank is connected to the solution dilution tank; and the first dissolving tank is connected to the solution dilution tank. The system can absorb CO2 in the exhaust and convert it into calcium bicarbonate solution, avoids the separation, compression and transportation of CO2, and has the advantages of compact structure, low operation energy consumption and no secondary pollution.

The soft package type battery shell comprises a base layer, a gas barrier layer and a sealant layer which are sequentially stacked, and the sealant layer comprises a particle type fire extinguishing agent. The particulate fire extinguishing agent includes one or more selected from the group consisting of a first fire extinguishing component including sodium bicarbonate, a second fire extinguishing component including calcium bicarbonate, a third fire extinguishing component including ammonium phosphate, and a fourth fire extinguishing component including urea, to provide a pouch type battery case having improved safety.

A carbonized brick of recycled concrete powders and a preparation method thereof are provided, belonging to the field of concrete materials. The preparation method includes: adding composition A to a liquid storage tank; introducing composition B into the liquid storage tank to react with a solid waste solution to generate calcium bicarbonate solution; filling recycled powders into a molding die, decomposing the calcium bicarbonate solution by heat, reacting generated carbon dioxide with calcium ions leached from a C—S—H gel in the recycled powders to produce calcium carbonate, and precipitating, crystallizing and cementing in the molding die together with calcium carbonate produced by decomposing calcium bicarbonate solution, and resulting in strength of the recycled powders.

Provided herein are processes and systems related to a carbon dioxide sequestration process, comprising a) calcining limestone using a fossil fuel alternative input to form a mixture comprising lime and a gaseous stream comprising more than about 30 vol % carbon dioxide; and b) treating the mixture comprising lime with atmospheric air and allowing carbon dioxide from the atmospheric air to react with the mixture and form a composition comprising calcium carbonate, calcium bicarbonate, or combination thereof. Provided also herein are processes and systems related to a carbon dioxide sequestration process, comprising a) calcining limestone using a fossil fuel alternative input to form a mixture comprising lime and a gaseous stream comprising more than about 30 vol % carbon dioxide; and b) treating the mixture comprising lime with natural water and allowing dissolved carbon dioxide in the natural water to react with the mixture to form a composition comprising calcium carbonate, calcium bicarbonate, or combination thereof.

The application discloses a kind of based on ammonium salt leaching agent cycle's smelting slag efficient low-consumption leaching method, belong to metallurgical solid waste resource utilization technical field.Water leaching is carried out to smelting slag, and the obtained water leaching residue is subjected to multistage countercurrent leaching using ammonium salt solution to obtain calcium-rich leaching solution, and the calcium-rich leaching solution is subjected to carbon fixation reaction with excess carbon dioxide gas to generate calcium bicarbonate solution;The calcium bicarbonate solution is subjected to neutralization precipitation with the obtained water leaching solution, liquid-solid separation, to obtain light calcium carbonate and ammonium salt solution, and the obtained ammonium salt solution is recycled for multistage countercurrent leaching.The method designs an ammonium salt solution closed-loop process and a calcium carbonate open-loop process, which not only reduces the acid and alkali consumption cost in the smelting slag leaching process, but also produces high-value light calcium carbonate products, realizes the resource utilization of all components of smelting slag, reduces the processing cost of smelting slag, and provides a new way for harmless, efficient and high-value utilization of steel smelting slag.

The invention provides a frozen pre-fried food wrapping material and a preparation method and application thereof.The frozen pre-fried food wrapping material comprises a basic wrapping powder mixture, a functional prefabricated material, water and a flavoring agent, and the functional prefabricated material comprises whey protein isolate, high-methoxyl pectin and a citric acid aqueous solution; the basic flour coating mixture comprises wheat flour, pre-gelatinized cassava starch, rice flour, konjac powder, sodium bicarbonate and calcium bicarbonate, and the temperature of the water is 0-5 DEG C. According to the invention, the whey protein isolate and the high-methoxyl pectin form a water-soluble electrostatic composition in an acidic environment, and the electrostatic composition can form a layer of film in a frying process, so that macromolecular grease invasion can be effectively blocked; the konjac powder, the pregelatinized cassava starch and other hydrophilic substances inside form a high-water-holding-capacity gel network close to the inner layer of the food materials, the resistance of outward migration of internal water is increased, juice is firmly locked inside the food materials, and the taste of crispy outside and tender inside is formed.

This invention provides a method for recovering lithium from lithium-containing aluminum electrolyte waste, relating to the field of lithium-containing waste resource utilization. The lithium-containing aluminum electrolyte waste is mixed with a calcium-containing substance and roasted. The calcium-containing substance includes a first calcium-containing substance and a second calcium-containing substance. The first calcium-containing substance is at least one selected from calcium sulfate, calcium bisulfate, calcium carbonate, or calcium bicarbonate. The second calcium-containing substance is at least one selected from calcium carbonate, bicarbonate, sulfate, bisulfate, hydroxide, oxide, or chloride. The molar ratio of calcium in the calcium-containing substance to aluminum in the lithium-containing aluminum electrolyte is controlled at 1-4:1. The molar amount of calcium in the carbonate, bicarbonate, sulfate, and bisulfate is 40%-80% of the total molar amount of calcium in the calcium-containing substance. After roasting, the roasted clinker is mixed with an acidic leachate for lithium extraction. This method significantly improves the lithium leaching rate and effectively and selectively recovers high-value lithium from lithium-containing aluminum electrolytes.

The disclosure relates to a process for producing magnesium hydrogen carbonate and / or calcium hydrogen carbonate. An anion exchanger loaded with bicarbonate ions is provided, and a solution containing magnesium salt and / or calcium salt is then passed through the anion exchanger.

The application relates to the technical field of concrete waste slurry application, and particularly discloses a process for preparing recycled aggregate from non-fluid silicate concrete waste. The process comprises the following steps: (1) after the non-fluid silicate concrete waste is finely ground, the non-fluid silicate concrete waste is uniformly mixed with a silicate cement, graphene, asbestos fiber, a ferrous sulfate or ferrous sulfate aqueous solution, and then granulated, the obtained granules are standard cured, and a pretreated body is obtained after completion; (2) the pretreated body is immersed in a calcium bicarbonate solution, after completion, the pretreated body is separated out and placed in an EDTA or EGTA-containing sodium carbonate solution for activation treatment. After completion, the obtained pretreated body is standard cured again, and recycled aggregate is obtained. The above process of the application utilizes the characteristics of the non-fluid silicate concrete waste to prepare high-strength recycled aggregate, not only realizes resource utilization of the non-fluid silicate concrete waste, but also makes the non-fluid silicate concrete waste better play its own advantages to obtain high-performance recycled aggregate products.

The invention relates to the technical field of magnesium alloy surface treatment, in particular to strontium salt and calcium salt composite chemical conversion liquid for magnesium alloy, a preparation method and a preparation method of a conversion film. The method comprises the following steps: firstly, preparing a saturated calcium bicarbonate solution and a saturated strontium hydroxide solution; sequentially adding a saturated strontium hydroxide solution and hydrogen peroxide into water to obtain a strontium hydroxide preparation solution; preparing a sodium bicarbonate solution; mixing the saturated calcium bicarbonate solution, the strontium hydroxide preparation solution and the sodium bicarbonate solution to obtain a strontium salt and calcium salt composite chemical conversion solution; and the magnesium alloy part to be treated is placed in the strontium salt and calcium salt composite chemical conversion liquid, and after no bubble emerges, the magnesium alloy part subjected to surface treatment is taken out, washed with water and blow-dried. The method is low in cost, low in energy consumption and environmentally friendly, and the prepared composite conversion film composed of SrCO3, CaCO3, MgCO3, MgO, Al2O3 and other phases is uniform, fine, smooth and flat and has excellent corrosion resistance.

This invention belongs to the field of water treatment and provides a zero-discharge hardness removal process using aluminum-based adsorbents. The process involves uniformly mixing sodium and aluminum salts in a solution to obtain a mixed solution; performing ion exchange with a cation exchange resin using this mixed solution to obtain an aluminum-based adsorbent; treating water with this aluminum-based adsorbent to adsorb calcium or magnesium ions, forming nano-sized aluminum hydroxide precipitates that adhere to the aluminum-based adsorbent framework, and collecting the effluent; regenerating the aluminum-based adsorbent with carbon dioxide gas to displace calcium or magnesium bicarbonate, collecting the effluent, and allowing it to settle to form calcium carbonate or magnesium carbonate precipitates, thus obtaining the final product. This hardness removal process does not use any chemical agents, only carbon dioxide gas as a regenerator. The regeneration process produces no waste liquid and simultaneously achieves carbon dioxide fixation and hardness ion removal, meeting the requirement of zero discharge.

The application discloses a production method and device of feed calcium with multiple particle sizes by concentrated acid method, and relates to the technical field of feed-grade calcium phosphate preparation. Carbon dioxide tail gas is sent into a washing tower, and washing liquid and washed carbon dioxide are obtained after the carbon dioxide tail gas is washed by process water; the washing liquid is sent into a slurry preparation tank, calcium carbonate is added for slurry preparation, and the washed carbon dioxide is sent into the slurry preparation tank; slurry after reaction in the slurry preparation tank is sent into a reaction tank, phosphoric acid is added into the reaction tank, and carbon dioxide-containing gas from the slurry preparation tank is blown into the reaction tank; slurry after reaction in the reaction tank is continuously reacted in a reactor, when the slurry is in a semi-dry state, the slurry is sent into a granulator by a spiral feeder; after granulation, drying, screening, crushing and cooling, feed calcium phosphate salt with multiple particle sizes is obtained. The carbon dioxide tail gas is used to prepare calcium carbonate emulsion containing calcium bicarbonate, the carbon dioxide is introduced into the reaction tank to improve the reaction efficiency of phosphoric acid and calcium carbonate, and a non-return material granulation process is adopted to increase the production efficiency of the feed calcium.

Method for producing calcium bicarbonate, comprising: mixing, by means of a mixer (101), water and calcium carbonate, thereby obtaining a first solution; providing a multiple scrubber (100) comprising: a cold steam scrubber (200), a shower scrubber (201), a plate scrubber (202) and a dehumidifier / fan (203); feeding, to the multiple scrubber (100), the first solution and a fluid comprising carbon dioxide; activating said multiple scrubber (100) to obtain a second solution comprising water, calcium bicarbonate and residues of calcium carbonate; obtaining, from said second solution, an aqueous solution of calcium bicarbonate. A system for producing calcium bicarbonate is also described.

Disclosed herein are oral care compositions for improving oral health and / or desensitizing teeth. According to one aspect, there is provided an oral care composition having from about 2% to about 10% by weight of a potassium source comprising potassium nitrate, potassium citrate, potassium oxalate, and combinations thereof; an abrasive comprising calcium carbonate, calcium bicarbonate, or a combination thereof; a fluoride source; and a polyol, wherein all weight percentages are based on the total weight of the oral care composition. The oral care composition may be substantially free or free of silica abrasives.

This application relates to the interdisciplinary field of inorganic compound synthesis and building materials technology, specifically to a method for preparing solid calcium bicarbonate using calcium-rich solid waste. The method includes: grinding: crushing and grinding the calcium-rich solid waste to obtain solid waste powder; preparing a leaching solution; leaching: adding the solid waste powder to the leaching solution for leaching, filtering to obtain a filtrate; and generating: adjusting the relative permittivity of the filtrate to <50, adjusting the pH range to 9-11, mixing thoroughly, introducing carbon dioxide gas to generate a white precipitate, centrifuging or filtering to obtain solid calcium bicarbonate. This application fully utilizes the alkalinity and calcium-rich properties of solid waste, meeting the requirements for calcium bicarbonate preparation. It not only solves the land occupation and pollution problems associated with solid waste but also produces a high-value-added material, opening up a new path for the resource utilization of solid waste in the interdisciplinary field of inorganic compound synthesis and building materials technology.

The utility model relates to the technical field of carbonization reaction equipment, and discloses nano calcium carbonate continuous carbonization reaction equipment which comprises a reaction mechanism, and a temperature control mechanism is arranged at the bottom end of the reaction mechanism. According to the continuous carbonization reaction equipment for the nano calcium carbonate, a calcium hydroxide solution is input through the liquid conveying pipe and atomized through the atomizing spray head, carbon dioxide guided in through the gas conveying pipe is diffused through the gas conveying spray head, gas-liquid two-phase full contact is achieved, calcium carbonate precipitates are generated, the precipitates are intercepted to the containing cabin through the filter screen, and redundant liquid is discharged through the discharging port; for side reaction, a temperature control medium is input through a liquid inlet of the temperature control mechanism, so that the liquid tank is kept in an environment of 35 + / -2 DEG C, and reverse dissolution of calcium carbonate is inhibited; and the CO2 concentration is adjusted to 8-12 vol%, so that the main and side reaction paths can be directionally regulated and controlled, the yield of nano calcium carbonate is ensured to be more than 95%, and the production of calcium bicarbonate can be switched.

This invention discloses an air particulate matter separation device and method. The device includes a fan, a purified water chamber, and a multi-stage separation chamber. A filter element is installed within the multi-stage separation chamber. The fan blows air carrying dust particles into the multi-stage separation chamber, causing the dust particles (calcium carbonate particles) to be filtered onto the filter element. The multi-stage separation chamber is connected to a first gas separation mechanism, which in turn is connected to the purified water chamber. The purified water chamber stores distilled water. The first gas separation mechanism separates carbon dioxide from the air and inputs the carbon dioxide into the purified water chamber, converting the distilled water into carbon dioxide-containing water. The purified water chamber is connected to the multi-stage separation chamber, and the filter element is rinsed using this carbon dioxide-containing water. During physical rinsing, carbon dioxide, water, and calcium carbonate react to form calcium bicarbonate dissolved in the water, effectively removing dust particles adhering to the filter element, preventing filter pore clogging, extending filter element life, and avoiding frequent filter element replacements.

The application discloses a method for preparing aragonite type calcium carbonate by fixing carbon dioxide with steel slag, which comprises the following steps: (1) crushing and grinding the steel slag into steel slag powder, and then activating the steel slag powder in ultrasonic waves to obtain ultrasonic-activated steel slag powder; (2) mixing the ultrasonic-activated steel slag powder with water, adding pure acetic acid solvent to warm and acidify, and preparing acidified steel slag; (3) CO2 gas quenching the acidified steel slag, adding water to the acetic acid leaching solution and the steel slag powder in a mass ratio of 3-10:1, adjusting the pH of the leaching solution to 7-9, stopping the CO2 input after 10-90 min of stirring, and filtering to obtain calcium bicarbonate filtrate; and (4) crystallizing and filtering the calcium bicarbonate filtrate to obtain aragonite type calcium carbonate. The method can fix carbon dioxide in tail gas on site by using the waste steel slag stacked in a steel plant, achieves the effect of "waste treatment by waste", the leaching reagent can be recycled, and the method is economic and environment-friendly, and solves the technical problems of utilization of steel slag waste and carbon dioxide resources.

The invention relates to the field of agricultural soil improvement, and discloses a conditioner for soda saline alkali soil and application, the conditioner comprises a calcium-based material, a sulfur-containing material and an improvement auxiliary agent; wherein the improvement auxiliary agent contains citric acid, polyaspartic acid and gallic acid, and the weight ratio of the citric acid to the polyaspartic acid to the gallic acid is (2-12): (0.5-5): 1. The conditioner contains a specific improvement auxiliary agent, can efficiently destroy the compact structure of calcium carbonate / calcium bicarbonate on the surfaces of soil particles and in pores, release fixed calcium ions and convert invalid calcium into effective calcium, and meanwhile, the conditioner can adjust the pH of the soda saline-alkali soil, reduce the alkalinity of the soil and achieve improvement of the soda saline-alkali soil. In addition, by adopting the preferable scheme, the pH of the soda saline-alkali soil can be further reduced, and the replacement reaction of calcium ions and exchangeable sodium ions can be efficiently realized.

The application relates to the photovoltaic manufacturing technical field, in particular to a photovoltaic wastewater zero-discharge treatment system and treatment method. The system comprises a dilute acid wastewater treatment device, a dilute alkali wastewater treatment device and a neutralized concentrated water filtering device. The dilute acid wastewater treatment device comprises a dilute acid wastewater filtering unit, an acid path concentrated water adjusting unit, a calcium fluoride crystallization unit and a calcium bicarbonate crystallization unit which are connected in sequence. The dilute acid wastewater treatment unit further comprises an adjusting pipeline which is connected between the upstream of the calcium fluoride crystallization unit, the calcium fluoride crystallization unit and the calcium bicarbonate crystallization unit and the downstream of the calcium bicarbonate crystallization unit. The adjusting pipeline can switch whether the concentrated water flowing out of the acid path concentrated water adjusting unit passes through the calcium fluoride crystallization unit and / or the calcium bicarbonate crystallization unit. The dilute alkali wastewater treatment device comprises a dilute alkali wastewater filtering unit and a silicic acid crystallization unit which are connected in sequence. The neutralized concentrated water filtering device is used for deep treatment of the crystallized concentrated water. The system can produce high-quality regenerated water and realize zero discharge while efficiently controlling energy consumption and chemical consumption.

This invention provides a roasting aid for lithium-containing aluminum electrolyte waste, its preparation method, application, and application method in the resource recovery of lithium-containing aluminum electrolyte waste, as well as roasted clinker, relating to the field of lithium-containing waste recycling. The roasting aid for lithium-containing aluminum electrolyte waste contains a first calcium-containing substance and a second calcium-containing substance. The first calcium-containing substance is at least one of calcium sulfate, calcium bisulfate, calcium carbonate, or calcium bicarbonate. The second calcium-containing substance is at least one of calcium carbonate, bicarbonate, sulfate, bisulfate, hydroxide, oxide, or chloride. The second calcium-containing substance and the first calcium-containing substance contain different or dissimilar anions. The molar amount of calcium in the first calcium-containing substance accounts for 40%-80% of the total molar amount of calcium. Furthermore, the ratio of the total molar amount of calcium in the first and second calcium-containing substances to the molar amount of aluminum in the lithium-containing aluminum electrolyte waste is 1-4:1. The roasting aid of this invention has high roasting efficiency, good roasting effect, and low energy consumption.

The utility model relates to a carbonized recycled aggregate preparation device which comprises a carbon dioxide gas cylinder, a first container for preparing a calcium bicarbonate solution and a second container for carbonizing recycled aggregate which are communicated in sequence, the first container and the second container are respectively provided with a first temperature controller and a second temperature controller which are used for controlling the temperature, the preparation of the calcium bicarbonate solution and the carbonization of the recycled aggregate are arranged in two different containers, and the temperature controller is arranged in each container; according to the present invention, the temperature suitable for each reaction can be adjusted during the generation of the calcium bicarbonate solution and the carbonization of the recycled aggregate, such that the preparation of the calcium bicarbonate solution can be adjusted to the low temperature so as to ensure the concentration of the calcium bicarbonate solution, and then the high-concentration calcium bicarbonate solution is introduced into the second container, and after the temperature is adjusted to a proper temperature through the second temperature controller, the recycled aggregate is carbonized, so that the carbonization effect of the recycled aggregate is improved.

The application relates to the technical field of sewage treatment, and discloses a composite material for tunnel construction sewage treatment and a sewage treatment method thereof, which is made from the following components in parts by weight: lanthanum-aluminum bimetal modified attapulgite, dopamine-coated modified magnetic nano composite particles, chitosan grafted polyacrylamide, aminotri(methylene) phosphonic acid, nano hydroxyapatite, calcium bicarbonate, polyaspartic acid zinc, sodium lignosulfonate and deionized water; through scientific proportioning of the components and optimization of key preparation processes, a synergistically efficient technical scheme is formed. From the micro level, the functions of the components are complementary and synergistic, ensuring the synchronous and efficient removal of suspended solids, heavy metal ions and organic pollutants; a series of problems existing in traditional tunnel construction sewage treatment, such as poor purification effect, slow separation speed, high cost and insufficient environmental protection, are solved.

The invention discloses a device and method for separating particulate matter in air, the device comprises a fan, a water purification bin and a multi-stage separation bin, a filter element is arranged in the multi-stage separation bin, the fan is used for blowing air with dust particles into the multi-stage separation bin, the dust particles are filtered on the filter element, the dust particles are calcium carbonate particles, and the filter element is used for filtering the air with the dust particles. The multi-stage separation bin is communicated with the first gas separation mechanism, the first gas separation mechanism is communicated with the water purification bin, the water purification bin is used for storing distilled water, the first gas separation mechanism is used for separating carbon dioxide in air, inputting the carbon dioxide into the water purification bin and converting the distilled water into a water body containing the carbon dioxide, and the water purification bin is communicated with the multi-stage separation bin; the filter element is flushed by a carbon dioxide-containing water body. During physical washing, carbon dioxide, water and calcium carbonate react to generate calcium bicarbonate dissolved in water, dust particles attached to the filter element are efficiently removed, filter holes of the filter element are prevented from being blocked, the service life of the filter element is prolonged, and frequent replacement of the filter element is avoided.

The invention relates to the technical field of saltpeter production, in particular to a heat exchanger descaling method which is characterized in that hydrochloric acid is mixed with mother liquor in advance so as to adjust the pH value range of the mother liquor, CO3 < 2-> can be converted into HCO3 <->, calcium carbonate with small solubility is converted into calcium bicarbonate with large solubility, calcium carbonate scaling precipitation is prevented, and the heat exchanger descaling effect is improved. The sodium sulfate heat exchanger is prevented from scaling, the production quality of sodium sulfate is effectively guaranteed, the pH value of a solution in each evaporation chamber can be rapidly adjusted by directly adding hydrochloric acid into each evaporation chamber, so that calcium carbonate with low solubility is converted into calcium bicarbonate with high solubility, and scaling formation is inhibited from the source.

The invention discloses a continuous preparation method of an acyl fluoride compound, according to the continuous preparation method, in the presence of a catalyst, perfluoroolefin with a general formula of R1R2C = CR3R4 and carbonyl fluoride are subjected to an addition reaction to prepare the acyl fluoride compound with a general formula of CFR3R4-CR1R2-COF, R1, R2, R3 and R4 are independently selected from CnF2n + 1, and n is 0-6; the catalyst is a non-loaded body porous catalyst and consists of bicarbonate and hydrofluoride, and the bicarbonate is selected from one or more of lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, cesium bicarbonate, magnesium bicarbonate, calcium bicarbonate, strontium bicarbonate and barium bicarbonate; the hydrogen fluoride salt is selected from one or more of lithium fluoride, sodium fluoride, potassium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride and barium fluoride; the mass percentage ratio of the bicarbonate to the hydrofluoride is (0-60%): (40-100%). The method is mild in continuous reaction condition, easy to operate, almost free of byproducts and suitable for continuous production.