A calcination resource utilization method for bamboo-wood cationic fiber pulping solid waste

Abstract

The present application relates to bamboo wood cationic fiber pulping solid waste resource utilization technical field, especially in kind of bamboo wood cationic fiber pulping solid waste calcination resource utilization method.The present application first carries out the overall analysis of bamboo wood cationic fiber pulping solid waste process and component, mainly including mineral solid waste (silica, iron ore, etc.), calcium carbonate solid precipitation (from lime and sodium carbonate reaction), lignin and lignin calcium solid precipitation (from wastewater reactor acidification precipitation).Based on this, the present application provides a kind of bamboo wood cationic fiber pulping solid waste calcination resource utilization method, by bamboo wood cationic fiber pulping solid waste is mixed calcination at low temperature, realize the resource utilization of bamboo wood cationic fiber pulping solid waste, not only improve the overall process resource utilization efficiency, and reduce the cost, further improve economic efficiency, wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of resource utilization technology for solid waste from bamboo and wood cationic fiber pulping, and particularly to a method for resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. Background Technology

[0002] Throughout history, paper products have been widely used in printing, product packaging, home decoration, and other industries, accompanying people's daily lives. Therefore, the pulp and paper industry plays a vital role in human survival and development. However, the pulp and paper industry is characterized by high emissions, high pollution, and high energy consumption. The large-scale harmful wastewater generated after pulping and papermaking contains large amounts of cellulose, lignin, and various chemicals, consumes a large amount of oxygen, and also produces solid waste, posing a potential threat to the ecological environment. Therefore, updating pulping technology and effectively treating wastewater and solid waste are important directions for the development of the pulp industry, and technicians have developed many new technical approaches in this regard.

[0003] With the increasing technology intensity and transformation and upgrading of the pulp and paper industry, some new technological demands have begun to emerge. For example, the scarcity of raw material resources has led to a growing emphasis on pulp yield within the industry, and pulping methods such as chemimechanical processes have gained further attention from technicians, who have also conducted further research on chemimechanical methods. In addition, some have proposed using bamboo and eucalyptus, which have short growth cycles, as raw materials to alleviate the scarcity of raw material resources.

[0004] Against this backdrop, engineers proposed a technical solution for bamboo and wood cationic fiber pulping, transforming ordinary bamboo and wood raw materials into high-value-added cationic lignocellulose materials. This significantly improves the utilization rate and product value of bamboo and wood resources, achieving a comprehensive utilization rate of over 95%. All scraps and debris are recycled, eliminating raw material waste and greatly enhancing resource utilization efficiency. The cationic lignocellulose prepared using this solution exhibits strong charge stability, excellent adsorption performance, and broader compatibility, making it suitable for high-end applications across multiple industries. Its market competitiveness far surpasses that of ordinary lignocellulose.

[0005] However, bamboo and wood cationic fiber pulping also has some drawbacks, such as the generation of solid waste. Therefore, how to treat the solid waste from bamboo and wood cationic fiber pulping is an urgent problem to be solved in this field. Summary of the Invention

[0006] In view of this, the present invention provides a method for the calcination resource utilization of solid waste from bamboo and wood cationic fiber pulping. The calcination resource utilization method provided by the present invention can utilize the high-value resources of solid waste from bamboo and wood cationic fiber pulping, and the calcination temperature is below 550 degrees Celsius, realizing the low-temperature resource utilization treatment of solid waste from bamboo and wood cationic fiber pulping.

[0007] This invention provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping by calcination, comprising the following steps: The solid waste from bamboo and wood cationic fiber pulping is subjected to a first calcination, a second calcination, and a third calcination in sequence. The temperature of the first calcination is 200~235 degrees Celsius, the temperature of the second calcination is 305~340 degrees Celsius, and the temperature of the third calcination is 520~550 degrees Celsius. The solid waste from bamboo and wood cationic fiber pulping includes calcium carbonate solid precipitate, lignin, and lignin calcium solid precipitate.

[0008] Preferably, the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:75~85.

[0009] Preferably, the solid waste from bamboo and wood cationic fiber pulping is pulverized before use; the target particle size for pulverization is 100~150 mesh.

[0010] Preferably, the temperature of the first calcination is 200-235 degrees Celsius, and the time is 45 minutes or more; the first calcination is carried out in an air atmosphere.

[0011] Preferably, the process includes a first heating before the first calcination; the rate of the first heating is 5~10℃ / min.

[0012] Preferably, the second calcination temperature is 305-340 degrees Celsius and the time is 30-50 minutes; the second calcination is carried out in an air atmosphere.

[0013] Preferably, the second heating is performed before the second calcination; the rate of the second heating is 3~5℃ / min.

[0014] Preferably, the temperature of the third calcination is 520-550 degrees Celsius, and the time is 1-3 hours; the third calcination is carried out in an air atmosphere.

[0015] Preferably, a third heating is included before the third calcination; the rate of the third heating is 5~10℃ / min.

[0016] Preferably, the third calcination process includes cooling; the cooling process includes rapid cooling and natural cooling in sequence; the rapid cooling rate is 15~20℃ / min, and the final temperature is not higher than 100 degrees Celsius.

[0017] Compared with the prior art, the present invention has achieved the following beneficial effects: This invention provides a comprehensive analysis of the process and composition of solid waste from bamboo and wood cationic fiber pulping, mainly including mineral solid waste (silica, iron ore, etc.), calcium carbonate solid precipitate (from the reaction of lime and sodium carbonate), and lignin and calcium lignin solid precipitate (from acidification precipitation in wastewater reactors). Based on this, this invention provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. By performing low-temperature mixed calcination of the solid waste, resource utilization is achieved, which not only improves the overall resource utilization efficiency of the process but also reduces costs, further enhancing economic benefits and showing broad application prospects.

[0018] Compared to traditional processes, the calcination resource recovery method provided by this invention features lower calcination temperatures, easier-to-obtain reaction conditions, lower costs, and outstanding economic efficiency. Through segmented calcination and controlled raw material ratios, this invention achieves excellent reaction results with impure raw materials (the purity of the aforementioned solid waste is very low compared to fresh raw materials), yielding high-purity lime, which can be used to treat wastewater from bamboo and wood cationic fiber pulping. This achieves the effect of "treating waste with waste," demonstrating significant ecological and economic value. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of this invention, the accompanying drawings used in the embodiments of this invention or in the prior art are briefly described below. For those skilled in the art, other drawings can be derived from the following drawings without creative effort, and all such drawings are within the protection scope of this invention.

[0020] Figure 1 This is a comparison chart of the lime content in the products of Examples 1-10 and Comparative Examples 1-10. Detailed Implementation

[0021] This invention provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping by calcination, comprising the following steps: The solid waste from bamboo and wood cationic fiber pulping is subjected to a first calcination, a second calcination, and a third calcination in sequence. The temperature of the first calcination is 200~235 degrees Celsius, the temperature of the second calcination is 305~340 degrees Celsius, and the temperature of the third calcination is 520~550 degrees Celsius.

[0022] In this invention, the solid waste from bamboo and wood cationic fiber pulping may include calcium carbonate solid precipitate, lignin, and lignin calcium solid precipitate.

[0023] In this invention, the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate can be 100:75~85, specifically 100:78, 100:80, or 100:83. By using the above-mentioned proportions, this invention can achieve the optimal reaction between calcium carbonate solid precipitate and lignin and lignin calcium solid precipitate, thus obtaining the target product lime to a greater extent for use in the alkalization reaction.

[0024] In this invention, the solid waste from bamboo and wood cationic fiber pulping can be pulverized before use; the target particle size can be 100-150 mesh, specifically 120 mesh. Using this particle size promotes effective contact between raw materials and helps reduce the temperature during the calcination process.

[0025] In this invention, the temperature of the first calcination is 200-235 degrees Celsius, specifically 205 degrees Celsius, 215 degrees Celsius or 225 degrees Celsius, and the time is more than 45 minutes, specifically 1 hour or 1.5 hours; the first calcination can be carried out in an air atmosphere.

[0026] In this invention, the first heating may be included before the first calcination; the rate of the first heating may be 5~10℃ / min, specifically 7℃ / min.

[0027] In this invention, the temperature of the second calcination is 305-340 degrees Celsius, specifically 310 degrees Celsius, 320 degrees Celsius or 330 degrees Celsius, and the time is 30-50 minutes, specifically 35 minutes, 40 minutes or 45 minutes; the second calcination can be carried out in an air atmosphere.

[0028] In this invention, the second heating may be included before the second calcination; the rate of the second heating may be 3~5℃ / min, specifically 4℃ / min.

[0029] In this invention, the temperature of the third calcination can be 520-550 degrees Celsius, specifically 530 degrees Celsius or 540 degrees Celsius, and the time can be 1-3 hours, specifically 2 hours; the third calcination can be carried out in an air atmosphere. This invention achieves improved lime purity and yield through the aforementioned first, second, and third calcinations. Specifically, the first calcination removes surface moisture and some adsorbed water from calcium carbonate, preparing it for subsequent calcination, and also carbonizes some impurities, reducing their interference with the high-temperature calcination (third calcination) stage; the second calcination, under the action of lignin calcium, degrades some lignin into phenolic compounds, guaiacol, astragalophenol, etc., providing assistance for the subsequent function of lignin; the third calcination, through the combination of lignin and the pyrolysis products of lignin from the second calcination, achieves the degradation of calcium carbonate into lime under low-temperature conditions, yielding the final product.

[0030] In this invention, a third heating may be included before the third calcination; the rate of the third heating may be 5~10℃ / min, specifically 7℃ / min.

[0031] In this invention, the third calcination may further include cooling; cooling may include sequential rapid cooling and natural cooling; the rapid cooling rate may be 15~20℃ / min, specifically 18℃ / min, and the final temperature may not exceed 100 degrees Celsius, specifically 90 degrees Celsius, 80 degrees Celsius or 50 degrees Celsius.

[0032] In this invention, cooling may further include pulverizing the resulting product; the target particle size of the pulverized product may be 5 to 15 mm, specifically 10 mm.

[0033] The product obtained by the above-mentioned calcination resource utilization method is mainly composed of lime, which can be used for the alkalization reaction of wastewater generated during the preparation of bamboo and wood cationic fibers, so as to realize the full utilization of resources and has broad application prospects.

[0034] To further illustrate the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and embodiments.

[0035] Example 1: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:75. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 85 minutes in air at a rate of 6°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 5°C / min and calcined at 320°C for 40 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0036] Example 2: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:77. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 225°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 5°C / min and calcined at 330°C for 35 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0037] Example 3: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:82. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 5°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 5°C / min and calcined at 330°C for 40 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0038] Example 4: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:85. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 70 minutes in air at a rate of 5°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 320°C for 40 minutes at a rate of 5°C / min. Subsequently, the temperature was increased at 535°C for 2 hours at a rate of 8°C / min. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0039] Example 5: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:80. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 225°C for 55 minutes in air at a rate of 10°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 4°C / min and calcined at 320°C for 40 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0040] Example 6: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:79. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 225°C for 50 minutes in air at a rate of 6°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 5°C / min and calcined at 330°C for 35 minutes. Subsequently, the temperature was increased at 10°C and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0041] Example 7: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 205°C for 85 minutes in air at a rate of 6°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 5°C / min and calcined at 320°C for 40 minutes. Subsequently, the temperature was increased at 10°C and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0042] Example 8: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:77. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 205°C for 90 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 10°C and calcined at 545°C for 1.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0043] Example 9: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:81. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 330°C for 40 minutes. Subsequently, the temperature was increased at 10°C and calcined at 535°C for 2 hours. Afterward, the temperature was decreased to 100°C at a rate of 20°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0044] Example 10: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 525°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0045] Example 11: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 520°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0046] Example 12: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 525°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0047] Example 13: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 530°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0048] Example 14: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 540°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0049] Example 15: This embodiment provides a method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping through calcination. The specific steps are as follows: Calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were separately pulverized to a particle size distribution of 100-150 mesh. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were weighed according to a mass ratio of 100:83. The calcium carbonate solid precipitate, lignin, and calcium lignin solid precipitate were mixed and calcined at 215°C for 60 minutes in air at a rate of 8°C / min. Then, while maintaining the air atmosphere, the temperature was increased at 3°C / min and calcined at 310°C for 50 minutes. Subsequently, the temperature was increased at 8°C / min and calcined at 545°C for 2.5 hours. Afterward, the temperature was decreased to 100°C at a rate of 15°C / min and allowed to cool naturally. The resulting product was pulverized to a particle size of 5-15 mm to obtain the lime product.

[0050] Comparative Example 1: The preparation method of this comparative example is the same as that of Example 10, except that the calcination at 215 degrees Celsius for 60 minutes is omitted.

[0051] Comparative Example 2: The preparation method of this comparative example is the same as that of Example 10, except that the calcination at 310 degrees Celsius for 50 minutes is omitted.

[0052] Comparative Example 3: The preparation method of this comparative example is the same as that of Example 10, except that the calcination at 525 degrees Celsius for 2.5 hours is omitted.

[0053] Comparative Example 4: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:70.

[0054] Comparative Example 5: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:65.

[0055] Comparative Example 6: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:90.

[0056] Comparative Example 7: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:95.

[0057] Comparative Example 8: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and calcium lignin solid precipitate is 100:100.

[0058] Comparative Example 9: The preparation method of this comparative example is the same as that of Example 10, except that the mass ratio of calcium carbonate solid precipitate to lignin and calcium lignin solid precipitate is 100:200.

[0059] Comparative Example 10: The preparation method of this comparative example is the same as that of Example 10, except that the temperature is increased at a rate of 3°C / min and calcined at 525°C for 2.5 hours.

[0060] Test Example 1: The products of Examples 1-10 and Comparative Examples 1-10 were tested, and the test results are shown in Table 1 and... Figure 1 As shown.

[0061] Table 1. Test results of Examples 1-10 and Comparative Examples 1-10:

[0062] According to Table 1 and Figure 1 It can be seen that the calcination resource utilization method provided by this invention can achieve efficient utilization of solid waste from bamboo and wood cationic fiber pulping. The resulting product can be recycled for wastewater treatment, demonstrating resource recycling and broad application prospects. Compared with comparative examples 1-10, it can be seen that after omitting the third calcination, calcium carbonate basically does not degrade, and the lime content is extremely low. This lime may be inherent in the raw materials. This invention, through raw material control and stepwise calcination, achieves an engineerable technology for producing lime from low-purity raw materials at low temperatures (approximately 400 degrees Celsius lower than traditional methods), providing a new option for the pulping industry.

[0063] The test results of Examples 11-15 are similar to those of Example 10, and will not be repeated here.

[0064] As can be seen from the above embodiments, the calcination resource utilization method for solid waste from bamboo and wood cationic fiber pulping provided by the present invention achieves low-temperature mixed calcination resource utilization of solid waste from bamboo and wood cationic fiber pulping by adjusting the composition, dosage, and multi-stage calcination combination, and finally obtains a lime product with high purity.

[0065] The embodiments of the present invention have been described above; however, these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. All other embodiments obtained by those skilled in the art based on the above embodiments of the present invention without inventive effort are within the protection scope of the present invention.

Claims

1. A method for the resource utilization of solid waste from bamboo and wood cationic fiber pulping by calcination, characterized in that, Includes the following steps: The solid waste from bamboo and wood cationic fiber pulping is subjected to a first calcination, a second calcination, and a third calcination in sequence. The temperature of the first calcination is 200~235 degrees Celsius, the temperature of the second calcination is 305~340 degrees Celsius, and the temperature of the third calcination is 520~550 degrees Celsius. The solid waste from bamboo and wood cationic fiber pulping includes calcium carbonate solid precipitate, lignin, and lignin calcium solid precipitate.

2. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The mass ratio of calcium carbonate solid precipitate to lignin and lignin calcium solid precipitate is 100:75~85.

3. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, Bamboo and wood cationic fiber pulp solid waste should be crushed before use; the target particle size for crushing is 100~150 mesh.

4. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The first calcination time is more than 45 minutes; the first calcination is carried out in an air atmosphere.

5. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The process before the first calcination also includes a first heating; the rate of the first heating is 5~10℃ / min.

6. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The second calcination takes 30 to 50 minutes and is carried out in an air atmosphere.

7. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The second heating process, preceding the second calcination, involves a second heating rate of 3-5 °C / min.

8. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The third calcination takes 1 to 3 hours and is carried out in an air atmosphere.

9. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The third heating process, preceding the third calcination, involves a third heating rate of 5-10 °C / min.

10. The method for resource utilization of solid waste from bamboo and wood cationic fiber pulping according to claim 1, characterized in that, The third calcination process includes cooling; cooling includes rapid cooling and natural cooling in sequence; the rapid cooling rate is 15~20℃ / min, and the final temperature is not higher than 100 degrees Celsius.

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