20 results about "Green liquor" patented technology

The invention relates to an oxygen delignification pulping method taking bagasse as a raw material, fine pulp and application of the fine pulp, and belongs to the technical field of pulping and papermaking. The pulping method comprises the following steps: preparing a cooking liquor with the alkali amount of 20-30% from sodium carbonate and sodium hydroxide in a mass ratio of (2-9): 1; mixing bagasse with the cooking liquor, and heating and preserving heat under an oxygen adding condition to obtain cooking slurry; washing and screening the cooked pulp to obtain fine pulp and black liquor; preparing green liquor from the black liquor, adding sodium hydroxide into the green liquor until the alkali consumption is the same as that of the cooking liquor, and recycling the green liquor to the cooking liquor. According to the invention, the used chemical agents are sodium carbonate as a main agent and sodium hydroxide as an auxiliary agent, so that corrosion to equipment is reduced, a causticization reaction process is omitted, harmful solid waste pollution caused by the causticization process is avoided, and direct cyclic utilization of the green liquor is realized. The content of silicon in the black liquor is relatively low, so that the risk of silicon interference in an alkali recovery section is reduced.

The invention belongs to the field of pulping and papermaking, and particularly relates to a method for promoting precipitation and sedimentation of silicon in non-wood pulp alkali recovery green liquor through Ca-Al synergism. The method comprises the following steps: 1, adding lime into the non-wood-pulp alkali recovery green liquor, carrying out a pre-causticization reaction, and ensuring that the use amount of the lime is 0.5-15% of the total causticized lime amount; secondly, aluminum salt is added into the green liquor treated in the first step for a silicon removal reaction, the molar ratio of the dosage of the aluminum salt to the silicon content of the green liquor is 0.1-2, and after the specified reaction time is reached, standing and settling are conducted. Through the Ca-Al synergistic effect, the settling speed of precipitated silicon is greatly increased, the settling height is remarkably reduced, the problems that the silicon removal rate is low by using a lime pre-causticization method alone and silicon particles are difficult to settle by using an aluminum salt method alone are solved, and an effective method is provided for industrial application of green liquor silicon removal; the problem of serious environmental pollution caused by discharge of a large amount of white mud is solved.

The invention discloses a method for preparing high-quality light calcium carbonate based on green liquid separation and impurity removal-crystal nucleus induction causticization granulation, and relates to the technical field of pulping and papermaking waste liquid treatment. According to the method, pulping black liquor is used as a raw material, calcium silicate is separated through fractional precipitation, granular calcium carbonate crystals are generated through crystal nucleus induction causticization reaction, and high-quality light calcium carbonate is prepared through multi-stage purification. The content of calcium carbonate prepared by the method can reach 98-99.5% of the purity of industrial calcium carbonate, the purity of calcium silicate byproducts is greater than or equal to 90%, the calcium silicate byproducts can be directly used for roadbed materials or cement retarders, the recovery rate of sodium hydroxide in the black liquor is greater than or equal to 92%, and resource utilization is realized.

The invention relates to the technical field of papermaking, and discloses a calcium carboaluminate silicon removal material as well as a preparation method and application thereof. Dispersing CaO in water to obtain lime milk; the preparation method comprises the following steps: respectively dissolving NaAlO2 and Na2CO3 in water, and mixing with lime milk; performing synthesis reaction; and drying and crushing the obtained product to obtain the calcium carboaluminate silicon removal material. The calcium carboaluminate prepared by the method has a regular layered structure, a larger specific surface area of 8.21 m < 2 > / g and a higher crystal water content of 14.14%, so that the calcium carboaluminate shows an excellent silicon removal effect in high-temperature green liquor, and the silicon removal rate can reach 85.36%. The method for removing silicon from the high-temperature green liquor by using the calcium aluminosilicate can be directly used for industrial production, is favorable for improving the silicon removal rate of the high-temperature green liquor, and also has a relatively good calcium aluminosilicate sedimentation effect.

To provide an information processing system or the like capable of properly estimating an event which may occur in a pulp manufacturing system.SOLUTION: A first step of cooking wood chips with white liquor, a second step of obtaining green liquor from black liquor produced in the first step, a third step of obtaining clarified green liquor from the green liquor, and a step of adding calcium oxide to the clarified green liquor to obtain white liquor and calcium carbonate; A fourth step of supplying white liquor to the first step and supplying calcium carbonate to the fifth step, and the fifth step of supplying calcium oxide obtained by calcination of calcium carbonate to the fourth step are combined, the parameter information acquisition unit acquires two or more parameters related to any of the first step to the fifth step as the parameter information, the relationship model information acquisition unit acquires relationship model information created in advance and indicating a relationship between an event or an index related to the event and two or more parameters, and the estimation unit estimates the event or the index related to the event based on the acquired parameter information and the relationship model information.SELECTED DRAWING: Figure 1

A method for separating lignin (9) from an alkaline aqueous slurry (5) containing lignocellulosic biomass material, the method being carried out in a pulp mill and comprising an alkaline first lignin precipitation step (20) and an acidic second lignin precipitation step (22), wherein the alkaline first lignin precipitation step (20) involves lowering an initial alkaline pH value of the aqueous slurry by means of a first acidifying agent to a lower alkaline pH value The first acidifying agent comprises or consists of sulphuric acid (19) produced from sulphur, which has been at least partly derived from a green liquor stripping process (15) in the pulp mill. A system for carrying out the method is also disclosed.

The invention discloses a causticization reaction-based carbonization reactor for purification of nanoscale calcium carbonate, and relates to the technical field of carbonization reactors, the causticization reaction-based carbonization reactor comprises a distributor, a base and a plurality of ring bodies, the ring bodies are concentrically distributed to form a concentric ring structure, one end of each ring body is inserted into the base, and gear rings are fixed on the inner and outer circumferential surfaces of each ring body; and the gear ring is alternately meshed with a plurality of gear sets in the base. Speed difference exists between the adjacent ring bodies during same-direction and reverse-direction rotation, so that the retention time of bubbles is prolonged, and the utilization rate of carbon dioxide gas is increased; by combining the intermittent and continuous air inlet composite mode, the requirements of most industrial scenes, especially papermaking green liquor causticization reaction recycling, stability, economical efficiency and productivity can be met, and meanwhile intermittent air inlet can be used for part of scenes to inhibit bubble coalescence so as to meet a small part of requirements.

The application discloses a method for improving the stability of bamboo green liquor, and belongs to the technical field of liquor brewing. The method for improving the stability of bamboo green liquor comprises adsorption treatment, i.e. using chelating resin to adsorb the bamboo green liquor. According to the method for improving the stability of bamboo green liquor provided in the application, the bamboo green liquor with complex components can still maintain good color and luster after being stored for a certain period of time, and has high color and luster stability.

The present invention relates to a mixing assembly for controlling the mixing of green liquor and a flocculant. This assembly comprises a mixing vessel (20) with a first end and a second end, an inlet (21) for supplying liquor and flocculant to the mixing vessel near the first end, an outlet (22), and a rotatable stirring device (31) near the first end for mixing the liquor and flocculant by agitation. The mixing vessel (20) has a length from the center of the inlet to the center of the outlet, and a maximum width perpendicular to this length, which is at least 1.5 times the maximum width. The invention also relates to a method for controlling the flocculation of the green liquor.

The invention relates to a method for manufacturing a belite cement clinker The method comprises steps of providing raw materials comprising 10 to 90 wt.% green liquor dregs (GLD), and 0 to 50 wt.% bio-based fly ash, based on total dry weight of the raw materials, and heating a mixture comprising the raw materials in a thermal treatment unit by using a process temperature and a residence time. The invention further relates to a belite cement clinker. The invention further relates to a belite cement composition. The invention further relates to method for manufacturing a belite cement composition.

The present invention discloses a chemimechanical pulp white mud recovery apparatus, and relates to the technical field of papermaking recovery, the chemimechanical pulp white mud recovery apparatus comprises a flocculation tank for recovering green liquor, and further comprises a variable flocculation stirring mechanism for improving the flocculation effect of the flocculation tank and extruding precipitated white mud, the regulation and control mechanism is used for controlling the variable flocculation stirring mechanism to spray out a flocculation agent in a variable mode, the control cabinet is used for controlling discharging to enable the variable flocculation stirring mechanism to change the state, and a recovery tank is arranged beside the flocculation tank. When the device is used for carrying out flocculation treatment on green liquor to recycle the green liquor, the flocculation precipitation rate of white mud in the green liquor can be increased by utilizing the matching effect of the variable flocculation stirring mechanism and the regulation and control mechanism, and meanwhile, the white mud can be automatically extruded after the flocculation precipitation is finished, so that the white mud can be recycled. And therefore, reusable liquid contained in the white mud is discharged, and the recovery effect is improved.

The invention relates to new solutions for effective recovery of chemicals in a Kraft pulp mill A method for recovering chemicals in a Kraft pulp mill is provided. The method comprises producing green liquor in a recovery boiler, conveying green liquor from the recovery boiler to a green liquor stripper, stripping the green liquor with a gas stream comprising or consisting of CO2 so as to produce a stripper off-gas, feeding the stripper off-gas to a sulfuric acid plant, and producing sulfuric acid from the stripper off-gas. Further, a system as well as use of the same for recovering chemicals in a Kraft pulp mill are provided.

[Summary] An information processing system, etc. that can appropriately estimate an event that may arise in a pulp manufacturing system. According to an aspect of the present disclosure, an information processing system for estimating an event that may arise in a pulp manufacturing system is provided in which the pulp manufacturing system comprises a combination of: a first step of obtaining pulp by cooking wood chips with white liquor; a second step of obtaining green liquor by treating black liquor generated in the first step; a third step of obtaining clarified green liquor by treating the green liquor; a fourth step of obtaining white liquor and calcium carbonate by adding calcium oxide to the clarified green liquor, supplying the obtained white liquor to the first step, and supplying the obtained calcium carbonate to a subsequent fifth step; and a fifth step of obtaining calcium oxide by calcining the calcium carbonate, and supplying the obtained calcium oxide to the fourth step, the information processing system comprises: a parameter information acquisition unit configured to acquire, as parameter information, two or more parameters related to any of the first step to the fifth step; a relationship model information acquisition unit configured to acquire relationship model information indicating a relationship between the event or an index related to the event, which has been created in advance, and the two or more parameters; and an estimation unit configured to estimate the event or the index related to the event based on the acquired parameter information and the relationship model information.

A lime slaker odor treatment system comprises a lime slaker, a lime silo and a causticizer; a cyclone feeder is provided on the top of the lime slaker, a green liquor inlet is provided on the top of the side wall of the cyclone feeder, and the green liquor inlet is connected to a green liquor pipeline; a lime inlet is provided on the top of the cyclone feeder, and the lime inlet is connected to a vertical lime pipeline, the top of the lime pipeline is connected to the discharge port of a screw conveyor, and the feed port of the screw conveyor is connected to the outlet of the lime silo via a feed pipe; an exhaust pipe is also provided on the top of the lime slaker, and the exhaust pipe is in an inverted U shape, with one end communicating with the top of the lime slaker and the other end communicating with the top of the causticizer; an odor pipe is connected to the top of the causticizer, and the odor pipe is connected to an odor collection and treatment system.

The invention belongs to the technical field of dissolving tanks, and provides a dissolving tank and an anti-caking device thereof, the anti-caking device comprises: a straight pipe arranged at the outer top of the dissolving tank and used for introducing dilute white liquid; the bent pipe is arranged at the top in the dissolving tank and close to an included angle between the inner side wall of the dissolving tank below the chute and the top cover of the dissolving tank, one end of the bent pipe penetrates through the top cover of the dissolving tank and is communicated with the straight pipe, and the other end extends along the inner side wall of the dissolving tank in an arc shape and is used for distributing dilute white liquid; the nozzles are respectively communicated with the bent pipe and are used for spraying dilute white liquid to the inner side wall of the dissolving tank; wherein the spraying direction of each nozzle can automatically deflect up and down along with the rising and falling of the liquid level of the green liquid in the dissolving tank. The nozzle automatically deflects up and down to cool and protect the inner side wall of the dissolving tank and clean the included angle between the inner side wall of the dissolving tank and the top cover of the dissolving tank, so that the inner side wall of the dissolving tank is effectively prevented from thermal deformation, the service life of the dissolving tank is prolonged, the maintenance cost is reduced, and potential safety hazards caused by caking are eliminated.

A method for transforming a black liquor, comprising the following steps: a) supplying a black liquor, b) gasifying the black liquor by means of supercritical water gasification in the presence of a hydrogenated carbon-free fuel, by means of which reaction products are formed, c) cooling the reaction products, by means of which a gaseous mixture is obtained which comprises at least methane and a green liquor comprising at least sulphur in the form of NaHS, Na2S and H2S.

The invention discloses polyacrylamide for alkali recovery. The polyacrylamide is prepared from the following raw materials in parts by weight: 60 to 80 parts of an acrylamide monomer, 5 to 15 parts of a cationic monomer, 10 to 20 parts of an anionic monomer, 2 to 8 parts of a hydrophobic modified monomer, 0.05 to 0.3 part of an initiator, 0.01 to 0.05 part of a chain transfer agent, 0.01 to 0.1 part of a cross-linking agent and 150 to 250 parts of deionized water. The polyacrylamide can efficiently flocculate suspended solid particles in the green liquor under the alkaline condition, the content of suspended solids in the green liquor is remarkably reduced, meanwhile, the dryness of green mud is improved, the size and treatment cost of the green mud are reduced, and the overall efficiency of an alkali recovery system is improved.

The invention belongs to the field of pulping and papermaking and functional material preparation, and discloses a method for preparing high-yield bagasse dissolving pulp in a green and circulating mode. According to the method, bagasse is used as a raw material, and a low-temperature oxygen-alkali cooking-biological enzyme enhanced hydrogen peroxide bleaching cleaning process system with sodium carbonate as an alkali source is constructed. The method is characterized in that bagasse is adopted as a raw material, dependence of traditional dissolving pulp preparation on wood fibers is broken through, and the raw material source is widened; a low-temperature oxygen-alkali cooking system is constructed, a green liquor self-circulation system is matched, efficient recycling of alkali components is achieved through evaporation concentration and high-temperature firing, the problems of silicon interference and white mud pollution in traditional alkali recovery are solved, and the closed-loop circulation rate of cooking waste liquor is 100%; a biological enzyme and hydrogen peroxide synergistic chlorine-free bleaching process is developed, so that the use amount of a bleaching agent and wastewater discharge are reduced, and the dissolving pulp with the yield of 35.2-37.8% is prepared. Through systematic innovation, a resource-saving and environment-friendly preparation system is constructed, the resource utilization efficiency and the clean production level are improved, and the method has great significance in industry green transformation.

The present invention discloses a chemical mechanical pulping white mud recovery device, which relates to the field of papermaking recycling technology. The device comprises a flocculation tank for recovering green liquor, a variable flocculation and stirring mechanism for improving the flocculation effect of the flocculation tank and squeezing the precipitated white mud, a control mechanism for controlling the variable flocculation and stirring mechanism to variably spray flocculation reagents, and a control cabinet for controlling the discharge of the variable flocculation and stirring mechanism to change the state of the variable flocculation and stirring mechanism. A recovery tank is provided adjacent to the flocculation tank. When flocculating green liquor for recovery, the device utilizes the coordinated action of the variable flocculation and stirring mechanism and the control mechanism to increase the flocculation and sedimentation rate of the white mud in the green liquor. Furthermore, after the flocculation and sedimentation are completed, the device automatically squeezes the white mud to discharge the reusable liquid contained in the white mud, thereby improving the recovery effect.

This utility model relates to the field of feeding technology for causticizing lime digestion and slag removal machines in papermaking alkali recovery, specifically a cyclone feeder for a lime digestion and slag removal machine. The feeder includes a cylinder body positioned between the lime digestion and slag removal machine and the lime feeding assembly. A green liquor inlet is also provided on the cylinder body. The cylinder body comprises an upper cylinder and a lower cylinder body. The lower cylinder body includes an inverted conical cylinder and an upright conical cylinder. The connection between the inverted and upright conical cylinders forms a neck. The bottom end of the upright conical cylinder is below the liquid surface in the lime digestion and slag removal machine. This cyclone feeder for a lime digestion and slag removal machine ensures thorough mixing of quicklime and green liquor while solving the problem of lime dust pollution. It reduces the processing load on the scrubber and decreases the formation of sludge within the scrubber. The structure is simple, with no maintenance or operating parts, resulting in low manufacturing costs. It is applicable to feeding lime digestion and slag removal machines in the causticizing section of alkali recovery in the papermaking industry and can also be used in similar solid-liquid mixing scenarios in other industries.