281results about "Lime production" patented technology

The invention relates to the technical field of lime kiln control, and discloses a lime kiln partition intelligent temperature control system and a storage medium, and the system comprises a data collection unit which is used for collecting state data of each region of a lime kiln; the working condition recognition unit recognizes working conditions based on the state data; the temperature control unit is provided with a PID (Proportion Integration Differentiation) control strategy and a prediction control strategy, and the opening degrees of the fuel regulating valves and the air regulating valves in different areas in the lime kiln are calculated according to the corresponding control strategies selected on the basis of working conditions; the discharging control unit is provided with a balance control strategy, the balance control strategy obtains the current discharging speed through the current productivity of the lime kiln and the material level height in the lime kiln, and the execution unit correspondingly controls the lime kiln according to the control quantity. The method effectively solves the problems of difficulty in multi-area coordination, poor working condition adaptability, high energy consumption and the like in a traditional control mode, and has the remarkable advantages of improving the temperature control precision, ensuring the production stability and reducing the energy consumption.

The invention relates to the technical field of lime shaft kilns, in particular to a full-automatic Kawasaki rotating lime shaft kiln device, and aims to solve the problems that during combustion of an existing lime shaft kiln, due to the fact that flame heat is concentrated on a local part, a disordered and uniform temperature field cannot be formed, and the calcination temperature of limestone is not uniform; limestone processing is achieved through the combustion mechanism on the supporting seat, the soaking assembly in the thermal insulation shell guides materials and cooperates with the combustion assembly for preheating, a flame jet device of the combustion assembly jets flames, the flames act with heating gas blown out by the high-pressure air pump to form a uniform temperature field, and the material guiding plate guides the materials to enter the rotating processing part. And the processing component disperses the materials through the rotating and material uniformizing assembly, so that the limestone is uniformly heated, and the uniform effect during limestone calcination is improved.

The invention relates to the technical field of rotary kiln processes, and provides a method for reducing nodulation in a lime rotary kiln, which comprises the following steps: S1, raw material pretreatment; s2, controlling the environment in the kiln; s3, optimizing the structural design of the kiln body; and S4, cleaning and maintaining in the kiln. According to the technical scheme, through the process steps of proportioning the raw materials, calculating the calcining temperature in a kiln, adjusting the stockline of a cooler to be 1.5 m, starting to discharge ash, and ending when the stockline of the cooler is 0.5 m, the CaO range of block ash is reduced by 11.44%, the SiO2 range is reduced by 1.52%, the activity range is reduced by 94.88 ml, the CaO range of surface ash is reduced by 6.95%, the SiO2 range is reduced by 0.54%, and the activity range is reduced by 100 ml; the data verifies that the quality of the finished product ash subjected to multi-fuel combustion in the rotary kiln is relatively stable after the new method is adopted.

The invention relates to the technical field of lime manufacturing, and provides a process and a system for manufacturing high-purity lime. The process comprises the steps of raw material pretreatment, plasma surface pretreatment, segmented atmosphere calcination, sound wave reinforced mass transfer, heat energy comprehensive utilization and intelligent control, rapid cooling, flue gas treatment and finished product packaging. The system comprises a raw material pretreatment unit, a plasma surface pretreatment unit, a multi-section gradient atmosphere calcining kiln, a sound wave reinforced mass transfer system, a heat energy comprehensive utilization and intelligent control system, a carbon dioxide capturing and recycling unit and a finished product cooling and packaging unit. Through raw material deep purification, surface activation treatment, gradient calcination and atmosphere accurate control, sound wave mass transfer reinforcement, intelligent optimization regulation and control, rapid cooling and flue gas purification and resource recovery, the purity and the reaction activity of a calcium oxide product are synergistically improved, and the production energy consumption and pollutant emission are remarkably reduced; and high-efficiency, clean and resource production of the high-purity lime is realized.

Equipment for crushing and grading magnesium oxide comprises a composite grading machine, a striking crushing and stripping machine, a spiral feeding machine, a circulating fan, a cyclone separator, a bag-type dust collector and an air compressor, and is characterized in that a crushing and grading unit is upgraded and grafted on the magnesium oxide crushing and grading equipment by utilizing the air flow advantage of closed-loop circulating air; on the basis of ensuring that the content of MgO is not reduced due to the influence of moisture and CO2 in air in the crushing and grading process, heavy MgCO3 fine powder and coarse MgO powder in raw powder are separated and graded to the maximum extent, and a low-grade magnesium oxide product containing a small amount of MgCO3 is obtained through an outlet of a 1 # air-lock valve of a composite grading machine; a high-grade magnesium oxide fine powder main product is obtained through an outlet of a second air-lock valve of the cyclone separator, and a high-grade magnesium oxide superfine powder product is obtained through an outlet of a third air-lock valve of the bag-type dust collector. By adopting a simple mode of coarse particle stripping shell shrinkage crushing instead of coarse particle grinding, the non-calcined magnesite powder is prevented from entering the fine powder, and the amount of the magnesium oxide fine powder is also increased. Operation is simple and easy to control, productivity efficiency is high, production is safe and environmentally friendly, and market application prospects are wide.

The present invention discloses an alkali-resistant castable for a lime rotary kiln working lining, as well as its preparation method and application. The present invention comprises the following raw materials in parts by mass: 100 parts premixed granular material; 50-55 parts premixed fine powder; and 9-13 parts potassium dihydrogen phosphate solution. The premixed granular material comprises magnesia aluminate spinel particles and calcium hexaaluminate particles; and the premixed fine powder comprises magnesia rhodonite fine powder, enstatite fine powder, zirconium boride fine powder, and amorphous Al2O3 fine powder. The alkali-resistant castable for the lime rotary kiln working lining prepared by the present invention has excellent construction performance. After being cast into the lime rotary kiln working lining, it does not require additional heat treatment or firing, thus saving energy. The castable has high high-temperature strength, low bulk density, low thermal conductivity, high alkalinity, strong resistance to alkali corrosion, and is non-ringing and slag-resistant. The castable has good fluidity, ensuring good overall sealing of the lime rotary kiln working lining. The alkali-resistant castable produces no toxic components before and after construction, making it environmentally friendly.

The invention belongs to the technical field of lime shaft kilns, and particularly discloses a double-hearth type lime shaft kiln which is characterized in that a calcining zone is connected to the lower portion of a preheating zone, a cooling zone is connected to the lower portion of the calcining zone, a discharging barrel is connected to the lower portion of the cooling zone, a discharging frame is connected to the lower portion of the discharging barrel, and a discharging mechanism is arranged in the discharging barrel; an air locking mechanism is arranged in the discharging frame. The discharging mechanism is arranged, four discharging holes of a center plate are matched with a sealing plate, materials fall from the center to the periphery in a dispersed mode, material segregation caused by single-channel discharging is avoided, the air locking mechanism is tightly attached to a conical discharging groove through a sealing plate, and a movable plate and the sealing plate are in linkage sealing, so that the discharging efficiency is improved. The external cold air is effectively prevented from flowing backwards and hot air in the kiln is effectively prevented from leaking, zero-time-difference synchronous actions of blanking hole opening, air locking releasing, blanking hole closing and air locking starting are achieved through linkage control of the blanking mechanism and the air locking mechanism, and the air leakage problem caused by delay of a traditional control system is avoided.

The lime kiln lining structure comprises a kiln top lining and a kiln body lining, and the kiln body lining comprises a first refractory brick layer, a second refractory brick layer, a first heat insulation layer, a second heat insulation layer and a third heat insulation layer which are sequentially arranged from inside to outside. Contact surfaces between two adjacent bricks in the first refractory brick layer are in concave-convex fit and are in sealed connection; the strength of the kiln top lining is higher than that of the first refractory brick layer, the second refractory brick layer, the first heat insulation layer, the second heat insulation layer and the third heat insulation layer, and the kiln top lining extends downwards to form a reinforcing part; kiln protecting plates are arranged on the inner side face of the kiln top lining and the upper side surface of the side, away from the second refractory brick layer, of the first refractory brick layer. The stability of the lime kiln lining can be enhanced, and the service life of the lime kiln can be prolonged; meanwhile, the heat preservation performance of the lime kiln can be enhanced, and heat loss is reduced.

The invention provides a low-nitrogen combustion decomposing furnace and a lime calcining system, and belongs to the technical field of limestone calcining, specifically, the low-nitrogen combustion decomposing furnace comprises a decomposing furnace body used for calcining and decomposing limestone, and a furnace chamber of the decomposing furnace body is divided into a material collecting area, a hot carbon reduction area and a combustion decomposing area; materials, combustion-supporting gas and fuel enter the decomposing furnace body in two ways, and the proportion of the materials, the combustion-supporting gas and the fuel entering the decomposing furnace body in the two ways is controlled, so that a hot carbon reduction area and a combustion decomposing area are formed in a furnace cavity of the decomposing furnace body. For example, the proportion of combustion-supporting gas in the combustion decomposition area is more, so that materials can be fully combusted, while the proportion of the combustion-supporting gas in the hot carbon reduction area can be reduced, so that insufficient combustion is carried out in the area, and meanwhile, suppression and reduction are carried out through fuel, so that nitrogen oxide passing through the area is subjected to reduction reaction to become carbon dioxide and nitrogen to be discharged; the content of nitrogen oxide is greatly reduced, and the nitrogen oxide treatment procedure of the subsequent exhaust process is reduced.

The invention discloses a simple and practical slide sieve, and relates to the technical field of refractory material manufacturing. The simple and practical slide sieve comprises a slide carriage shell, a sieving assembly is arranged in the slide carriage shell, an overhauling assembly is arranged on one side of the slide carriage shell, the sieving assembly comprises a sieve arranged in the slide carriage shell, and lifting lugs are fixedly installed on the two sides of the sieve. The screening problem is solved by the self-gravity of the arranged screening assembly in the using process, only the low-power bin wall vibrator is periodically used for vibration, the cost is remarkably saved, the size is small, the weight is light, installation and maintenance are convenient, the structure is simple, multiple inspection holes are formed in the top of the slide sieve, the sieve net is convenient to overhaul and replace, and sampling and testing are convenient; the vibrating screen device replaces traditional vibrating screen equipment, is obvious in using effect especially in occasions for treating and screening lime or making sand and other fine powder materials, meanwhile, is small in installation space occupied area and light in weight, and can still achieve the screening function under the condition that the space layout is compact.

The application discloses a low-ash-consumption converter smelting method, adopts single-slag smelting, controls the converter scrap steel ratio in 8% to 26%, controls the top blowing oxygen supply flow in 3.0 to 4.0 Nm 3 / (min·t), controls the bottom blowing argon flow in 0.03 to 0.10 Nm 3 / (min·t); the smelting process is improved by the cooperation of the gun position and the charging; the solid waste slag is added in the converter blowing process, the content of CaO in the slag is controlled in 45% to 55%, and the content of MgO is controlled in 5.5% to 7.5%; meanwhile, the dust removal pressure ball is added to improve the activity of FeO in the slag, and the terminal carbon content of the converter is controlled to be less than or equal to 0.05%. By adding the solid waste slag in the smelting process, the slag needed to oxidize a large amount of iron elements to generate FeO is reduced, so that the total iron content of the slag is reduced; by adding the synthetic slag, the liquidity of the slag is ensured, and the carbon-oxygen reaction is promoted; the total iron content of the low-carbon steel converter terminal slag is stably controlled to be less than 14.5%, the metal yield is provided; the lime addition amount can be reduced, the lime addition amount is controlled to be less than or equal to 10 kg / t, and the cost is reduced.

The utility model relates to a single-chamber lime shaft kiln with a central burner, and belongs to the technical field of kiln chamber structures of lime kilns. Comprising a furnace body (1) and a central burner (8), the outermost layer of the furnace body (1) is of a steel plate structure, the interior of the furnace body (1) is a lime kiln chamber built by refractory materials, the furnace body (1) is sequentially provided with a preheating section (3), a calcining section (6) and a cooling section (9) from top to bottom, an inner cavity of the preheating section (3) is of a straight barrel type structure, and inner cavities of the calcining section (6) and the cooling section (9) are of a big-end-down circular truncated cone type structure. And the central burner (8) is arranged at the central position of the bottom of the furnace body (1) and is of a thin circular truncated cone structure with a small upper part and a large lower part. The device has a simple structure, is convenient to manufacture, can reduce the formation of suspended materials of the lime kiln, prolongs the normal operation time of the lime kiln, can improve the yield of the lime kiln, ensures the good operation of the lime kiln, and improves the production benefit of the lime kiln.

The utility model relates to the technical field of furnace valve body devices, in particular to a gas and material linkage feeding valve for an industrial furnace. Comprising a valve body, the valve body is sequentially provided with a first channel, a second channel and a third channel, the first channel and the second channel are distributed on the left side of the valve body, the axes of the first channel and the second channel are perpendicular to each other, a valve assembly used for controlling opening and closing of the first channel and the second channel is arranged behind the valve body, and a control valve is arranged at the third channel. A blanking opening is formed in the lower part of the right side of the valve body; the air inlet, the air outlet and the feeding port are integrated in the valve body, the size specification of the whole device is greatly reduced, the occupied space area is reduced, meanwhile, a closed structure is formed by the whole device and a kiln body after the whole device is installed, and the dust raising condition is avoided.

The utility model relates to the technical field of calcining furnaces, in particular to a microwave heating high-temperature circulating flash calcining furnace, which comprises a cylindrical furnace body, a strong wave-transparent layer arranged on the inner wall of the cylindrical furnace body, a fire-resistant furnace lining arranged on the inner wall of the strong wave-transparent layer, a microwave generator arranged on the periphery of the cylindrical furnace body, and a preheater connected with the upper end of the cylindrical furnace body, a dust removal assembly is arranged above the preheater, and a discharging machine is arranged at the lower end of the cylindrical furnace body and connected with a cooling machine. According to the utility model, the microwave generator is used for calcining magnesite, dolomite, limestone, kaolin, clay, illite and the like, can be used for calcining in a reduction furnace or a vacuum reduction furnace, and is also suitable for high-temperature and ultrahigh-temperature flash sintering high-grade refractory materials; the device has the advantages of low investment cost, small occupied area, high resource utilization rate and the like.

The utility model discloses a device for detecting oxygen content in a kiln body of a light-burned magnesia rotary kiln. The device comprises an oxygen analyzer, wherein the oxygen analyzer consists of a detection unit (oxygen probe) and a control unit (transmitter). Wherein the detection unit is arranged at the end part of the rotary kiln body, and the detector is composed of a sensing probe, a protection tube, a junction box, a standard gas port, a flange and other main components. The whole device is of a totally-closed structure, so that the sealing performance of the whole device is improved, and the service life is prolonged. The control unit is a terminal for a user to operate integrated functions and comprises an operation panel, a display interface and a current output port. The utility model discloses a device for detecting oxygen content in a light-burned magnesia rotary kiln body, relates to the technical field of rotary kiln oxygen content detection equipment, and aims to control the rotating speed of an air blower according to the oxygen content so as to achieve the purpose of controllable oxygen content. Therefore, energy is saved, and electric energy of enterprises can be saved.

The present application relates to a rotary kiln cooler with external air chamber, comprising upper bin body, ring beam, central air distributor, chamber air distributor, lower cone bin, discharging cone and air supply pipeline; the rotary kiln cooler uses two different cooling methods to cool materials at different heights; in the upper part of the cooler, a plurality of air distributors embedded in the material layer and adapted to the shape characteristics of the material layer directly supply air to the material layer for pre-cooling; in the lower part of the cooler, the material is divided into multiple streams, and a plurality of air supply chambers are arranged to achieve uniform cooling in multiple regions; the cooler has simple structure, low material cooling temperature, can cool high-temperature materials from about 1100 DEG to more than 30 DEG to 50 DEG above room temperature, and has sufficient cooling, no red material inclusion, high thermal efficiency, and remarkable energy saving and emission reduction effect.

The application discloses a device and a production method for producing low-sulfur and low-chlorine lime powder by calcining limestone powder, and belongs to the field of limestone powder production and steelmaking. The decomposition furnace is divided into a high-temperature oxygen-deficient combustion region, a first limestone decomposition region and a second limestone decomposition region. A high-temperature oxygen-deficient CaO-free environment is created in the high-temperature oxygen-deficient combustion region, so as to promote the volatilization of residual KCl and NaCl, and then the residual KCl and NaCl are discharged through bypass air release technology. Limestone is added in the first decomposition region for decomposition, and combustion-supporting air is added in the second limestone decomposition region for strengthening combustion effect. In this way, the decomposition rate of limestone can be improved, the quality of steelmaking lime can be improved, and the steelmaking cost can be reduced.

The invention relates to the technical field of cranes, in particular to a hoisting device facilitating fixation of a kiln shell. Comprising a mounting frame, fixing seats, rotating wheels, a chain plate, a driving motor I and the like, the fixing seats are symmetrically connected to the bottom face of the mounting frame, the rotating wheels are rotationally connected to the fixing seats, the chain plate is wound on the rotating wheels, the driving motor I is mounted on the side faces of the fixing seats, and the end of a rotating shaft of each rotating wheel is connected with an output shaft of the driving motor I. The driving motor I drives the rotating wheels to rotate to lower the chain plates, the fixing rods and the moving frame can be connected in an inserted mode, so that the chain plates and the steel wire rope form a whole, the side faces of the four chain plates are limited through the four rotating wheels, the chain plates can be prevented from shifting in the front, back, left and right directions, and the service life of the chain plates is prolonged. Therefore, the steel wire rope can be prevented from deviating, the kiln shell can be prevented from shaking in the hoisting process, and it is guaranteed that the kiln shell can be rapidly aligned and installed.

The device comprises a flash replacement kiln, the flash replacement kiln comprises a powder-fuel gas heat exchanger and an oxygen-powder bin, slag sludge is ground by a Reynolds mill after moisture is evaporated and falls into the oxygen-powder bin, oxygen powder and fuel gas in the kiln are mixed and then subjected to fuel gas combustion, powder vapor is heated to 550-650 DEG C and subjected to a replacement reaction, slaked lime powder is generated, and the slaked lime powder is discharged into the flash replacement kiln. And the powder-fuel gas heat exchange tube is frequently impacted to reduce the temperature to 80-90 DEG C, CO2-enriched gas flow enters the drying kiln and the CO2-enriched gas-oxygen heat exchanger to be cooled, and part of condensed water is separated out by the cyclone dehydrator and sprayed into the kiln. The particle size of the limestone powder is smaller than 200 meshes, the temperature of an upper inner cavity is 550-650 DEG C, and the steam supply coefficient is 1.03-1.05. The limestone slag sludge can be recycled. The method is low in investment, high in waste heat recovery rate, low in emission, free of burning reduction of products, long in service life and large in carbon capture potential, and the key management object lime kiln device of the national two-high project is prevented from being used.

Method for calcining carbonate mineral stones in a parallel flow regenerative kiln wherein the method comprises an extraction step of the heated cooling gas through a series of extracting port located in an effective cooling zone within a cooling zone below a connecting channel, said heating cooling gas enters into an implementation port orifice and passes into a port duct to reach an evacuation element at an average extraction velocity comprised between 0.5 and 5 m / s.

The application discloses a suspension calcining system with a CO2 partial pressure reduction function and a method for preparing high-activity lime, and belongs to the technical field of lime stone calcination. The system comprises a pretreatment unit, a calcining unit, a cooling unit, a dust removal unit, a CO2 treatment unit and a product bin. The steps for preparing high-activity lime are as follows: after crushing the lime stone raw ore, the lime stone powder is added into a lime stone powder feeding bin, is fed into a cyclone preheater for three-stage preheating, is added into a suspension calcining furnace for calcination, air is introduced into the bottom of the calcining furnace during the calcination process, and the powder is ensured to be in a suspension state at all times; the powder after the calcination is sent into a cyclone cooler for three-stage cooling, and high-activity lime is obtained. In the process of preparing high-activity lime, the powder is heated more uniformly, the heat transfer efficiency is higher, the flowing gas timely discharges the CO2 generated by the decomposition, the CO2 treatment equipment is used for separation, the lime stone decomposition is moved to a positive direction, the decomposition speed is accelerated, and the decomposition efficiency is improved.

The application provides a lime rotary kiln preheater push head material return recovery device and relates to the technical field of lime calcination. The device comprises a preheater main body, a plurality of push heads are respectively arranged in a plurality of through channels formed in the preheater main body, one end of the through channel is connected with the outside world, and the other end is connected with a vertical feeding channel of the preheater main body; a layered space is formed between the upper part of the through channel and the upper part of the push head, two baffle structures are respectively connected with the two ends of the through channel, the distance between the bottom of each baffle structure and the upper part of the push head is less than 1.5 mm, a plurality of balls are arranged in the layered space, the push head is hollow, a plurality of through holes with a diameter less than 1.5 mm are arranged on the upper surface of the hollow part of the push head, the through holes are connected with the inside of the push head and the layered space, and the hollow space of the push head is connected with an external material collecting bin through a material guide pipe. The application can avoid the powder from sliding from the gap between the preheater main body and the push head, thereby reducing the waste of raw materials.

The present invention relates to a rotary kiln for burning carbonate-containing material, in particular limestone or dolomite, including a rotary tube having an inlet end for feeding the material to be burned and an outlet end for discharging the burnt material, and a burner unit arranged in the region of the outlet end, the rotary tube having an inlet zone at its inlet end and an outlet zone at its outlet end, a preheating zone and a combustion zone being arranged between the inlet zone and outlet zone in the direction of transport of the material. The rotary kiln is characterized according to the invention in that at least one projection is arranged in the outlet zone of the rotary tube, the at least one projection having a contour tapering in the direction of rotation of the rotary tube. The present invention further relates to a method for burning carbonate-containing material, in particular limestone or dolomite.

The utility model relates to a magnesite calcining system, which comprises a feeding device, a vertical preheater, a rotary kiln, a cylindrical cooler, a dust remover and a fan, the discharge end of the feeding device is positioned above the inlet of the vertical preheater, the outlet of the vertical preheater is connected with the rotary kiln, a burner is arranged at the kiln head of the rotary kiln, and the cylindrical cooler is connected with the rotary kiln. An outlet of the rotary kiln is connected with an inlet of the cylindrical cooler, an inlet of the dust remover is communicated with a smoke port of the vertical preheater, an outlet of the dust remover is connected with an inlet of the fan, and an outlet of the fan is connected with the chimney. According to the utility model, the vertical preheater is adopted, the pressure loss is low, and the air distribution is uniform, so that the preheating efficiency is high, the power consumption of the system is low, the decomposition rate of preheated magnesite raw materials entering a kiln is high, the small-particle-size magnesite raw materials of 10-50mm can be calcined, proper pressure and stroke of the hydraulic push rod can be determined according to different feeding particle sizes of the magnesite raw materials, the material pushing balance is ensured, and the energy consumption is low. The resource utilization rate is improved; and a cylindrical cooler is selected, so that the cooling effect is better.

The utility model discloses novel energy-saving limestone calcining treatment equipment, which relates to the technical field of limestone processing, and comprises a base and a calcining kiln arranged on the base, the calcining kiln comprises a calcining cylinder, a feeding cylinder, a sealing cover and a discharging pipe; the calcining barrel is of a hollow structure, one end of the calcining barrel is open, the feeding barrel is rotationally arranged on the outer wall of the open end of the calcining barrel, the sealing cover is arranged at the end, away from the end cover, of the feeding barrel, and the discharging pipe is arranged below the side, away from the feeding barrel, of the calcining barrel; an electric heating plate is arranged in the interlayer of the calcining cylinder; two bearings are arranged on the outer wall of the calcining cylinder, the calcining cylinder can rotate in the bearings, a first lifting device used for adjusting the angle of the calcining cylinder is arranged at the bottom of each bearing, and the first lifting devices are arranged at the top of the base; and the function of uniform calcination is achieved, exhausted hot air is utilized, limestone is preheated, the cost can be reduced, and the practicability is improved.

The present invention discloses a decarbonation process of carbonated materials, in particular limestone and dolomitic limestone, with CO2 recovery in a multishaft vertical kiln (MSVK) comprising a first, a second, and optionally a third shaft with preheating, heating and cooling zones and a cross-over channel between each shaft, alternately heating carbonated materials by a combustion of at least one fuel with at least one comburent up to a temperature range in which carbon dioxide of the carbonated materials is released, the combustion of the fuel and the decarbonatation generating an exhaust gas, the decarbonated materials being cooled in the cooling zones with one or more cooling streams, wherein a mixing between the exhaust gas and the one or more cooling streams is minimized by operating said kiln in a mode in which between two subsequent alternating heating cycles between the first and the second or the third shaft, the decarbonated materials in at least the first, the second and / or the third shaft are cooled with the one or more cooling streams while a supply of the fuel in each shaft is stopped.

The specification relates to a method and a system for adjusting pH of green liquor dregs. The method comprises contacting a slurry containing green liquor dregs (100, 200, 300, 400, 500) with flue gas (101, 201, 301, 401, 501). The system comprises a recovery boiler (105) configured to burn black liquor to produce smelt, a smelt dissolving tank (107) configured to dissolve the smelt to produce green liquor comprising green liquor dregs, and a green liquor clarifier / filter (103) and / or a dregs filter (104) configured to separate a slurry containing green liquor dregs (100, 200, 300, 400, 500) from the green liquor. The system further comprises a vessel (102, 202, 302, 402) configured to receive a slurry containing green liquor dregs (100, 200, 300, 400, 500) and a gas inlet (210, 310, 410, 510) configured to convey flue gas (101, 201, 301, 401, 501) to be contacted with the slurry containing green liquor dregs (100, 200, 300, 400, 500).

The present invention relates to a method for calcining mineral rock in a regenerative co-current vertical shaft furnace, comprising collecting a portion of the gaseous waste discharged from the furnace shaft in a preheating mode (2) in a recirculation circuit (18), mixing the collected portion of the gaseous waste with a high concentration of oxygen from an oxygen source (20) to form an oxidizing mixture, and inserting the oxidizing mixture into the top of the shaft (1) in a calcining mode, thereby ensuring combustion of the fuel in the presence of oxygen, wherein the gaseous waste discharged from the furnace has a high concentration of CO2.

The utility model relates to the technical field of magnesia production, in particular to a kiln entering device for magnesia production, which comprises a funnel, a screening component is arranged in an inner cavity of the funnel, the screening component comprises two convex blocks, the outer sides of the two convex blocks are fixedly connected with the inner wall of the funnel, a screen is arranged above the two convex blocks, and the outer side of the screen is fixedly connected with the inner wall of the funnel. Springs are arranged at the joints of the two ends of the bottom of the screen and the protruding blocks, and striking plates are arranged above the two sides of the top of the screen. The magnesite is firstly placed on the screen, then the motor operates, the motor drives the rotary table to rotate, the rotary table drives the guide rod to rotate, the guide rod is matched with the guide groove to drive the push plate to move downwards, the push plate drives the push rod to move downwards, the movable plate is matched with the push rod to move downwards, and the push rod drives the striking plate to move downwards. The striking plate drives the screen to press downwards, and at the moment, the screen is matched with the protruding block to drive the spring to conduct extrusion.

The invention provides a method for efficiently dephosphorizing converter slag by using electric furnace slag, which comprises the following steps: discharging the electric furnace slag after electric furnace smelting is finished, sampling and analyzing main chemical components of the electric furnace slag, and calculating the amount of active lime needing to be supplemented and added; the discharged electric furnace slag is conveyed to a converter area through a special slag tank with a heat preservation function, and the hot-state electric furnace slag is poured into a converter through a traveling crane; the method comprises the following steps: firstly adding scrap steel into a converter, then adding molten iron, supplying oxygen for blowing, finally adding active lime, adjusting the alkalinity of slag to 2.5-4.5, blowing to the end point, and tapping. According to the method, the low-phosphorus characteristic of the electric furnace slag is combined, the electric furnace slag has good interface reaction performance and dephosphorization capacity in the thermal state and is directly returned to the converter smelting process, lime consumption is reduced, efficient dephosphorization of the converter slag is achieved, efficient dephosphorization and resource utilization of the electric furnace slag are achieved, and the method has the advantages of saving energy, reducing emission, reducing cost, improving efficiency and recycling resources.