308 results about "Carbonatation" patented technology

The invention relates to a kitchen waste oil recovery treatment method, which comprises: S1, carrying out multi-field synergistic pretreatment: sequentially carrying out ultrasonic wave and high-frequency pulse electric field treatment on waste oil to break an emulsion layer, adding magnetic nanoparticles to adsorb polar impurities, and carrying out magnetic field separation to obtain high-purity oil; s2, supercritical catalytic reaction: under the CO2 supercritical condition, using a core-shell structure composite catalyst to synchronously perform transesterification reaction and glycerol dehydration reaction; s3, dynamic membrane separation: separating biodiesel and glycerol in real time through an intelligent membrane assembly; s4, gradient utilization of energy: recovering reaction waste heat to drive membrane distillation to concentrate wastewater, and using tail gas CO2 for carbonation reaction to generate calcium carbonate. Through four core technologies of multi-field collaborative pretreatment, low-temperature supercritical catalysis, dynamic membrane separation and energy gradient utilization, triple limitations on efficiency, cost and environmental protection in the prior art are remarkably broken through.

The invention provides compositions and methods directed to carbonation of a cement mix during mixing. The carbonation may be controlled by one or more feedback mechanisms to adjust carbon dioxide delivery based on one or more characteristics of the mix or other aspects of the mixing operation.

The invention relates, inter alia, to a method for filling a liquid into a container. The method comprises carbonating the liquid using a carbonator. The method comprises continuously reducing a pressure of the carbonated liquid to below a saturation pressure of carbon dioxide in the carbonated liquid and to above or substantially equal to an ambient pressure using a filling valve. The method further comprises filling the container with the pressure-reduced liquid using the filling valve.

The invention relates to the technical field of industrial control, and discloses a soda water production line intelligent control method and system based on the Internet of Things, and the method comprises the steps: obtaining a backpressure valve reference pressure value according to the obtained real-time dynamic data through employing a pre-constructed carbonation digital twin model, and calculating the backpressure valve reference pressure value according to the backpressure valve reference pressure value; the carbonation digital twinning model is set to obtain a theoretical pressure value by adopting the Henry law according to the target gas content and the real-time data of the mixed liquid temperature, and obtain a predicted pressure value by adopting the pre-constructed pressure prediction model according to the target gas content, the real-time data of the raw material liquid injection flow and the real-time data of the carbon dioxide injection flow; further obtaining a reference pressure value of the back pressure valve; according to a first difference value between the target gas content and the real-time gas content of the mixed liquid, a first feedback correction algorithm is adopted to correct the reference pressure value of the back pressure valve, and a dynamic pressure control instruction of the back pressure valve is obtained; and controlling the back pressure valve to execute the back pressure valve dynamic pressure control instruction. According to the method, the taste stability of the soda water is effectively improved.

The invention discloses an energy system and method for coupling calcium-based thermochemical heat storage and carbon capture. The energy system comprises a calcination unit, a carbon dioxide pretreatment storage unit, a calcium oxide heat exchange storage unit, a carbonation reaction unit and a heat utilization unit which are arranged based on a boiler. The calcining unit takes green valley electricity as energy to drive calcining reaction to realize heat storage, and generated CaO is processed by the calcium oxide heat exchange storage unit and then is stored for use in a heat release stage; generated COs are stored for standby application after passing through the carbon dioxide pretreatment storage unit; in the heat release stage, CaO and the desulfurized flue gas are subjected to heat release carbonation reaction in the carbonation reaction unit, and heat is released; caCO3 generated by the carbonation reaction can be used for the next heat storage stage; and the heat released by the carbonation reaction is conveyed to the heat utilization unit for heat exchange. Through coupling of calcium-based thermochemical heat storage and carbon capture, green electricity and off-peak electricity are fully utilized, and efficient storage and gradient utilization of energy are achieved.

The invention belongs to the technical field of dangerous solid waste resource utilization, and relates to a method and a system for washing, decontaminating and preserving calcium of fly ash through carbonation coupling ultrasonic two-stage pretreatment. The method comprises the following steps: exposing fly ash in air to carry out natural carbonation pretreatment until the pH value of the fly ash is not higher than 9 to obtain a pretreated product; mixing the pretreated product with an NH4HSO4 solution, carrying out ultrasonic pretreatment, and then stirring and washing with water; according to the method, deep dechlorination of the fly ash is achieved, the problem that heavy metal leaching exceeds the standard is effectively solved, the Ca component in the fly ash is reserved to a great extent, and the dual purposes of effective pollution control and efficient resource reservation are achieved.

A carbonation device for beverages includes a carbonation tank to receive a beverage to be carbonated and carbon dioxide so as to generate a carbonated beverage, carbonated with the carbon dioxide, and a dispensing device in fluid communication with the carbonation tank to dispense, through a duct, the carbonated beverage to a container for carbonated beverages, the carbonated beverage flowing along the duct in a flow direction.The carbonation device further includes a carbonation sensor associated with the duct and having a radiation source to generate a radiation which strikes the duct along an irradiation direction incident to the flow direction.The carbonation sensor also includes a first photodiode placed on the irradiation direction from a side opposite to the radiation source with respect to the duct, or as an alternative, a second photodiode placed along a diffusion direction substantially orthogonal to the irradiation direction.

The invention discloses a steel slag carbon sequestration reaction device, and belongs to the technical field of reaction devices. The device comprises a reactor which is internally provided with a heating part, a partition plate and a water storage disc, is externally connected with a gas supply bottle and a steam generator, and realizes parameter regulation and control through a controller. During working, steel slag is placed on the partition gauze, the heating part is heated, CO2 is introduced into the gas bottle, the steam generator and the water storage disc provide steam, the driving unit drives the partition and the water storage disc to swing, and gas-solid contact is strengthened; the water storage tank, the sealing cylinder and the like form a water circulation system to automatically supplement and return water; and the pressure release valve guarantees safety. Through the synergistic effect of temperature, humidity and mechanical swing, the carbonation reaction efficiency of the steel slag and CO2 is improved, and automatic operation of steel slag carbon sequestration is achieved. The device has the advantages that mass transfer is enhanced through mechanical swing, energy is saved through closed water circulation, steel slag is prevented from falling off through gauze design, waste is treated with waste, and high efficiency and environment friendliness are achieved.

The present invention relates to a method of producing a carbonated composite:a. providing a particulate mineral material, wherein the mineral material comprises metal slag, wherein the metal slag comprises steel slag;b. providing a modifier, wherein the modifier comprises sodium gluconate;c. mixing the mineral material and the modifier with water to form a slurry;d. treating the slurry with carbon dioxide, to form a wet solid residue, wherein the concentration of carbon dioxide is greater than about 10 vol%; ande. drying the wet solid residue to form the carbonated composite.

The invention relates to a method for recovering lithium and fluorine from aluminum electrolysis hazardous waste, which comprises the following steps: firstly, mixing organic polyol and alkaline hydroxide according to a molar ratio of 1: (0.5-2) to obtain a eutectic solvent; heating the eutectic solvent to 80-150 DEG C, and adding a proper amount of raw material fine powder and calcium oxide for reaction leaching; carbonating and filtering the leachate to obtain lithium carbonate; washing the leaching residues with an acetic acid solution to obtain a calcium fluoride product; the concentration of fluorine ions in the leachate is smaller than or equal to 200 ppm, and the purity of calcium fluoride is larger than or equal to 90%; the leaching rate of lithium in the method is greater than 85%; the slag feeding rate of fluorine is greater than 95%; and no hydrogen fluoride gas is generated in the method. According to the method, a non-toxic and biodegradable eutectic solvent is adopted as a leaching agent, and efficient leaching of lithium and fluorine in the aluminum electrolysis dangerous waste materials is achieved; calcium oxide is used as a precipitating agent, free fluorine is promoted to be precipitated and recycled as calcium fluoride, the whole process meets the requirement of green metallurgy, and the win-win situation of resources and the environment is achieved.

The invention provides a device and method for directly mineralizing carbon dioxide in air by using industrial solid waste carbide slag, the device comprises a raw material closed-loop crushing and weighing system and a main reactor system, the raw material closed-loop crushing and weighing system is used for controlling the fineness of crushed carbide slag to be that the mass of particles with the particle size smaller than 2 mm accounts for 90%-100% of the total mass; the main reactor system comprises a bubbling bed mineralization reactor, a riser mineralization reactor and a gas-solid parallel flow downer mineralization reactor which are connected in sequence. The raw material crushing and screening system controls the granularity of the carbide slag to be-2mm, the content of the carbide slag is 90-100 wt%, then the carbide slag is fed into the main reactor system, the main reactor system works cooperatively, the bubbling bed completes pre-carbonation of alkaline substances on the surface layer and the shallow layer of the carbide slag, and the riser and downer coupling system further carbonates an intermediate product. And finally, efficient mineralization of the carbide slag is achieved, the mineralization rate is high, the conversion rate is high, the product granularity is stable, system adjustment is intelligent, CO2 emission can be effectively reduced, and resource utilization of industrial solid waste is promoted.

A method may include: introducing a resin modified cement slurry into a wellbore penetrating a subterranean formation, the subterranean formation comprising a caprock and a carbon dioxide injection zone, the resin modified cement slurry comprising: a resin; a hardener, a hydraulic cement; and water; and setting the resin modified cement slurry to form a set cement wherein the set cement forms a carbonation-resistant barrier in the carbon dioxide injection zone in the subterranean formation.

The invention relates to a method and a system for washing, dechlorinating and protecting calcium of fly ash based on carbonation pretreatment, and belongs to the technical field of resource utilization of dangerous solid wastes. The method comprises the following steps: exposing fly ash with the water content of 10-20% in air to carry out natural carbonation pretreatment, so that the pH value of the fly ash is not higher than 9; and washing the fly ash subjected to natural carbonation pretreatment by adopting a citric acid solution. According to the method provided by the invention, the defects of traditional water washing are overcome, the Ca-based component in the fly ash can be retained while the chlorine reaches the standard, and the mass loss caused in the fly ash elution process is reduced to a certain extent, so that the resource property of the fly ash is well retained, and the resource utilization value of the fly ash is improved.

The invention provides a power generation system and method based on carbonation calcination cycle coupling thermochemical energy storage. The power generation system comprises a carbonate calcination reactor, a COturbine power generation unit, a carbonation reactor, a thermochemical energy storage unit, a heat exchange network and a control system. According to the invention, industrial waste heat or renewable energy electric power is utilized to drive carbonate calcination to generate high-temperature COs to push the turbine to generate power; meanwhile, a calcined product CaO / MgO enters a carbonation reactor to absorb COO in smoke or the atmosphere, carbon sequestration circulation is completed, high-temperature heat needed by calcination is supplied by high-grade heat energy stored by a thermochemical energy storage unit in the charging stage, and the heat energy comes from surplus electric power or system power generation tail gas waste heat; the thermochemical energy storage unit releases heat to drive calcination in the discharging stage, and power grid peak regulation and energy time shifting are achieved. The problems of intermittency and carbon emission of traditional thermal power / wind and light power generation are solved, and integration of efficient, low-carbon and schedulable power output and carbon capture is achieved.

The thermal chemical heat storage and carbon capture system comprises a coal-fired boiler, a calcination reactor and a carbonation reactor, the calcination reactor extracts high-temperature flue gas from the front wall of a hearth of the coal-fired boiler, the high-temperature flue gas drives CaCO3 in the calcination reactor to be decomposed into CaO and CO2, and heat storage is achieved; the reacted flue gas is pumped back into a tail flue of the coal-fired boiler, and the flue gas flow required by the reaction is controlled through a flow control valve on a pumping pipeline; caO generated by the calcination reaction can enter the carbonation reactor in the heat release stage, a heat release carbonation reaction is carried out, heat is released, CaCO3 obtained after the heat release reaction returns to the calcination reactor through a pipeline to serve as a reaction raw material, and CO2 obtained after the heat release reaction is output to a heat supply system. The integration of heat storage, heat release and carbon capture is realized by utilizing calcium-based material circulation, and the peak regulation capacity and the carbon capture economy of the coal-fired unit are remarkably improved.

The present invention relates to hazardous waste treatment technology, and aims to provide a method and system for efficient detoxification, quality improvement and reuse of fly ash from garbage incineration. The method utilizes a stirred ball mill reactor, a secondary water washing unit, a tertiary water washing unit and a fired-free brick preparation unit arranged in sequence, and couples a wet mechanochemical method with a carbonation, multi-stage water washing and fired-free pressing treatment process to achieve detoxification, quality improvement and reuse of fly ash from garbage incineration; before the flue gas is introduced to start the carbonation reaction, the fly ash is first subjected to a wet mechanical ball milling pretreatment, and a heavy metal composite stabilizer is added according to the characteristics of the reaction system, so that phosphate and tris-mercapto-s-triazine trisodium salt react with heavy metals respectively to stabilize the heavy metals in the solid phase medium. The present invention can improve the ability of fly ash to seal carbon dioxide, and the hardness of the obtained water washing liquid is lower than , and the heavy metal content is extremely low, which reduces the cost of the existing evaporation crystallization process; the risk of heavy metal leaching is low, the fly ash dechlorination efficiency is high, and the mechanical properties of the prepared fired-free bricks are better than those of the prior art.

The invention relates to the technical field of building materials, in particular to a carbon sequestration concrete solid brick prepared from coal-based solid waste and a preparation method of the carbon sequestration concrete solid brick. The carbon sequestration concrete solid brick is prepared from the following raw materials in parts by weight: 20 to 30 parts of fly ash, 65 to 75 parts of furnace bottom slag and 5 parts of cement, wherein the fly ash is secondary ash, the particle size of the furnace bottom slag is smaller than or equal to 4.75 mm, and the mark number of the cement is P.O 42.5. The method comprises the following steps: firstly, enabling carbon dioxide to react with alkaline components such as dicalcium silicate in the fly ash to form carbonate so as to realize effective carbon sequestration; and then through secondary mineralization maintenance, carbon dioxide, active components such as calcium and magnesium in the cement and dicalcium silicate which is not completely reacted in the fly ash are subjected to carbonation reaction, so that a product layer filling effect is realized. According to the invention, the building material with good carbon sequestration performance and excellent mechanical properties is prepared by utilizing industrial solid waste and carbon dioxide, so that energy conservation and emission reduction are realized, meanwhile, greenhouse gas emission is reduced, and the performance of the building solid waste brick is enhanced.

The invention relates to the technical field of aluminum oxide preparation, in particular to a method for preparing flaky aluminum oxide by using electrolyte waste liquid and flaky aluminum oxide. The method comprises the following steps: carrying out carbonation reaction on the electrolyte waste liquid by using carbon dioxide to obtain aluminum hydroxide precipitate; washing the aluminum hydroxide precipitate for the first time by using a washing agent to obtain a washed aluminum hydroxide solid-phase substance with a preset sodium content; calcining the washed aluminum hydroxide solid-phase substance to obtain a gamma-type aluminum oxide precursor; carrying out molten salt reaction on the composite molten salt system and the gamma-type aluminum oxide precursor to obtain a flaky aluminum oxide crude product; wherein the composite molten salt system is a mixture of sodium chloride, potassium chloride and sodium sulfate; and carrying out secondary washing on the sheet-shaped aluminum oxide crude product to obtain a sheet-shaped aluminum oxide product. According to the method, the flaky alumina with the high radius-thickness ratio is prepared under fluoride-free and strong acid conditions through a three-step core strategy of resource utilization of waste electrolyte, accurate sodium content control and directional induction of composite molten salt.

The invention provides a method for preparing high-purity vanadium pentoxide from carbonation leachate. The method comprises the following steps: S1, adding aluminum salt into the carbonation leachate to remove silicon, and carrying out solid-liquid separation to obtain silicon-removed liquid; s2, mixing the silicon-removed liquid with ammonium salt, and performing solid-liquid separation after vanadium precipitation to obtain crude ammonium metavanadate; s3, re-dissolving the coarse ammonium metavanadate, carrying out stirring reaction on the obtained coarse ammonium metavanadate re-dissolved slurry, and carrying out solid-liquid separation to obtain an ammonium metavanadate solution; s4, a complexing agent and ammonium salt are added into the ammonium metavanadate solution for vanadium precipitation, and high-purity ammonium metavanadate is obtained after solid-liquid separation; and S5, carrying out high-temperature calcination on the high-purity ammonium metavanadate to obtain the high-purity vanadium pentoxide. According to the method provided by the invention, the high-purity vanadium pentoxide with low impurity content is obtained by adopting the technological means of deeply removing silicon, re-dissolving to remove iron and separating cations such as calcium, potassium, sodium and the like into the vanadium product through complexing crystallization, and the method is simple in technological process, low in auxiliary material consumption and relatively low in cost.

The present application aims at the problems of excessive consumption of traditional cement limestone resources, excessive energy consumption and high carbon emission, and provides a carbonated hardened low-calcium cement and a preparation and hardening method thereof, which is a hardening method for curing low-calcium cement by CO2 carbonation. The mass percentage composition of cement raw material components is: limestone: 60-70%, sandstone or clay or silica ash: 15-25%, phosphogypsum, fluorogypsum or desulfurization gypsum: 5-25%, component A: 0.5-2%. Component A is composed of the following raw material components in mass percentage: fluorite 0-50%, barium slag: 0-50%, lithium slag 0-50%, wood ash 0-50%, industrial sodium carbonate 0-30%. The composition design of carbonated hardened cement clinker minerals is C2S: 10-90%, C5S2$: 10-90%, C$: 0-5%, C4A3$: 0-10%, etc. In the present application, the limestone required for the cement clinker is lower than that of ordinary Portland cement clinker, the calcination temperature is reduced by 200-350 DEG C than that of ordinary Portland cement clinker, and the energy consumption and carbon emission are significantly lower than those of Portland cement; the low-calcium cement is hardened by CO2 carbonation curing, which can make the cement obtain excellent mechanical properties within 2 hours.

A process for the preparation of carbonated recycled concrete fines, particularly recycled concrete fines from construction and demolition waste, and carbonated recycled concrete fines prepared by the process, is described. The process relates to accelerated mineral carbonation of recycled concrete fines having a specific moisture content. Also described is further processing the carbonated recycled concrete fines into secondary aggregate as well as uses and methods involving the carbonated recycled concrete fines and / or aggregate.

The invention belongs to the technical field of thermochemical energy storage, and discloses a calcium-based thermochemical energy storage coupled coal-fired unit carbon capture system and an operation method thereof, the calcium-based thermochemical energy storage coupled coal-fired unit carbon capture system comprises a coal-fired unit subsystem and a calcium-based thermochemical energy storage subsystem; the coal-fired unit subsystem comprises a boiler, a desulfurizing tower and a chimney which are connected in sequence; a flue gas inlet of the calcium-based thermochemical energy storage subsystem is connected with a flue gas outlet of the desulfurization tower, and a flue gas outlet of the calcium-based thermochemical energy storage subsystem is connected with an inlet of the chimney; wherein the calcium-based thermochemical energy storage subsystem is used for heating and decomposing calcium carbonate into calcium oxide and pyrolysis gas by utilizing peak regulation plant power consumption of the coal-fired unit subsystem, and is also used for generating calcium carbonate and releasing heat by utilizing carbonation reaction of desulfurized flue gas and calcium oxide; thermal chemical energy storage is coupled in the carbon capture process, the near-zero-energy-consumption carbon capture effect is achieved, meanwhile, frequency modulation and peak regulation of a coal-fired unit can be achieved, the energy utilization efficiency of the system is high, and operation is flexible.

The invention belongs to the field of thermochemical energy storage, and discloses a calcium-based thermochemical energy storage system and method coupled with a flue gas direct carbon capture system, and the calcium-based thermochemical energy storage system comprises a flue gas calcination reaction system, a CO2 collection system and the flue gas direct carbon capture system; a material inlet of the flue gas calcination reaction system is connected with a material outlet of the flue gas direct carbon capture system, a material outlet of the flue gas calcination reaction system is connected with a material inlet of the flue gas direct carbon capture system, and an inlet of the CO2 collection system is connected with exhaust gas of the flue gas calcination reaction system; the flue gas calcination reaction system is used for calcining calcium carbonate by using high-temperature flue gas so as to decompose calcium oxide and carbon dioxide to realize heat storage; the carbon dioxide collecting system is used for collecting and storing carbon dioxide; the flue gas direct carbon capture system is used for carrying out carbonation reaction on the desulfurized flue gas and calcium oxide to generate calcium carbonate and realize heat release; the storage and release process is independently carried out, the system design is simple, and the flexibility is high.

A method of sequestering carbon uses a mixed component gas that includes carbon dioxide, dissolves the carbon dioxide in a liquid under pressure, and pumps the resulting carbonated liquid into a subterranean formation.

A carbonation machine includes a carbonation head comprising: a carbonation lever configured to be operated by a user to assume a carbonation position to carbonate a liquid in a bottle connected to the carbonation head; a plunger for operating a valve of a gas canister between a closed position and an open position, whereby, when the carbonation lever assumes a carbonation position, the plunger causes the valve to open so as to allow carbon-dioxide from the gas canister to flow into the bottle to carbonate the liquid; and a retractor configured to interact with the carbonation lever such that when the carbonation lever assumes the carbonation position the retractor retracts during a predetermined period of time from an initial deployed state to a retracted position, so as to cause the plunger to move to the closed position and cause the valve to close.

The application relates to the technical field of aluminum hydroxide, in particular to a preparation method of coarse-grained aluminum hydroxide; the preparation method comprises the following steps: continuously decomposing sodium aluminate solution through carbonation to obtain coarse-grained aluminum hydroxide slurry; drying the coarse-grained aluminum hydroxide slurry, and then performing multi-stage continuous screening and multi-stage air separation to obtain high-quality coarse-grained aluminum hydroxide products; the continuous decomposition through carbonation comprises continuously decomposing in a gradient-decreasing manner of aluminum oxide concentration; the particle size of the coarse-grained aluminum hydroxide products meets the requirements of D10>=145 mu m, D50>=220 mu m and D90>=300 mu m; the existing sodium aluminate decomposition stage is introduced with continuous carbonation decomposition, the continuous decomposition process is controlled in a gradient-decreasing manner of aluminum oxide concentration, and then the particle size of the dried aluminum hydroxide is accurately graded through multi-stage continuous screening and multi-stage air separation, so that the high-quality coarse-grained aluminum hydroxide products with concentrated particle size distribution are obtained.

The invention relates to a water carbonator with an integrated water filter and / or mineralization stage, which can enable a rapid preparation of high-quality carobonated water despite different water qualities of the water to be treated, the water being forced through the filter and / or the mineralization stage by the CO2 gas pressure of the gas cylinder.

Provided are: a calcium-based carbonic acid compound, the shape of which is controlled so as to have a high aspect ratio; and an inorganic molded body. The present invention provides a calcium-based carbonic acid compound wherein: the content of phosphorus atoms is 1,000-15,000 ppm; the content of sulfur atoms is 2,000 ppm or less; and the aspect ratio of the average major axis to the average minor axis is 6-19.

The invention provides a bouquet-shaped calcium carbonate preparation method, and relates to the technical field of calcium carbonate preparation processes. The preparation method comprises the following steps: 1) adding polyhydroxy organic acid into water as a base solution; 2) preparing a calcium hydroxide suspension as a calcium source; (3) simultaneously adding a calcium source into the base solution and introducing CO2 gas; 4) adjusting the adding speed of a calcium source in real time to control the reaction conductivity interval until the carbonation reaction is finished to obtain a calcium carbonate suspension; and 5) precipitating, filtering, drying and screening the obtained suspension to obtain a target product. According to the invention, the formation of bouquet-shaped calcium carbonate crystals is controlled by combining conductivity regulation and control and an organic molecule induction method. The method is simple in operation process and small in chemical reagent addition, and the prepared bouquet-shaped calcium carbonate is uniform in morphology, good in dispersion, multiple in interfacial active sites, large in specific surface area and rich in pores and has a secondary fine structure.

The present invention relates to a process for binding carbon dioxide to a waste building material 10, wherein the reaction is carried out in a carbonation reactor 20, wherein a waste building material 10 is fed to the carbonation reactor 20, wherein a carbon dioxide-containing gas 30 is fed to the carbonation reactor 20, and wherein a carbonation product 50 is discharged from the carbonation reactor 20, characterized in that the alkaline earth content of the waste building material 10 fed to the carbonation reactor 20 and / or of the carbonation product 50 discharged from the carbonation reactor 20 is determined by means of elemental analysis 60, wherein the degree of carbonation C of the carbonation product 50 is determined by IR spectroscopy, and wherein a carbonation degree limit value Cmax is set.wherein if the carbonation degree limit Cmax is undershot, the supply of the waste material 10 to the carbonation reactor 20 is reduced and / or the supply of the carbon dioxide-containing gas 30 to the carbonation reactor 20 is increased, wherein if the carbonation degree limit Cmax is exceeded, the supply of the waste material 10 to the carbonation reactor 20 is increased and / or the supply of the carbon dioxide-containing gas 30 to the carbonation reactor 20 is reduced.