The hottest new way to produce paperboard

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A new way to produce paperboard

the total output of paper and paperboard in China takes flexible packaging film as an example, with 18.2 million tons in 1993, 21.383 million tons in 1994 and 28.123 million tons in 1995, ranking third in the world, second only to the United States and Japan. However, according to the per capita consumption of paper and paperboard, in 1994, the world average was 47.7 kg. Asia has the function of computer automatic processing and the experimental curve shows that the per capita consumption was 23.6 kg, China's per capita consumption was 20.2 kg, and the largest consumption was 332.6 kg in the United States, 266.1 kg in Finland and 233.2 kg in the Hong Kong Special Administrative Region. It can be seen that despite the rapid development of the paper industry, its output is still far from meeting the needs. Moreover, China's non wood raw materials account for 87.5% of the paper industry, and low-grade products account for 50%, and the quality is far from meeting the demand

since the 15th CPC National Congress, with the deepening of reform, the market competition mechanism has been continuously strengthened, and it is impossible to rely on the planning mechanism or administrative means. Only by constantly developing itself in the dynamic competition process of survival of the fittest, can enterprises be invincible. The current market competition is also facing the internationalization of the domestic market. The Chinese market will be a part of the world market. Relying on tariffs to protect the closed country can no longer meet the requirements of economic development. Since the beginning of 1996, there has been a sudden change in the paper market, from the seller's market to the buyer's market. There is a large backlog of products in paper enterprises, and the whole industry is facing difficulties. In this situation, China imported 4.4944 million tons of paper and paperboard in 1996, nearly 20% of the national output, an increase of 48.38% over the import of 3.02 million tons in 1995. From January to March 1997, 1.13 million tons were imported, an increase of 58% over the same period last year. So we can no longer just concentrate on increasing production without analyzing the market

how to develop the paper industry also faces the primary problem of environmental protection. A few years ago, there were many small and medium-sized paper mills. In addition to the original paper mills, the pollution of the paper industry has endangered cities, rural materials, oceans, rivers and lakes, and is becoming more and more serious. If we do not make up our minds, modern people cannot live, and will endanger future generations! On May 15, 1996, President Jiang Zemin issued Presidential Decree No. 66, which issued the law of the people's Republic of China on the prevention and control of water pollution. Article 23 of the law prohibits the construction of small chemical pulp without water pollution control measures... And other enterprises that seriously pollute the water environment. Article 24 it is required that Units discharging (polluting) substances that cause serious pollution of water bodies should be treated within a time limit. The State Council issued the "decision on Several Issues concerning strengthening environmental protection" again in document GF [96] No. 31, which clearly stipulates that small paper mills with an annual output of less than 5000 tons will be banned by September 31, 1996, and that all industrial enterprises in the country will meet the emission target by 2000. Especially in the heavily polluted Huaihe River Basin, the State Council required to "ensure that the discharge of industrial pollution sources in the whole basin is up to the standard in 1997 and that the water body in the Huaihe River Basin will become clear in 2000". In areas where the pollution is not as serious as the Huaihe River Basin, it is natural to meet the discharge standards as soon as possible. Under the correct decision of the central government, national legislation and strong law enforcement by governments at all levels, 4081 small paper mills had been shut down nationwide by December 24, 1996, accounting for 37% of the total number of paper mills. According to the 1995 national industrial census, there are 11025 enterprises in the country. There is only one Fujian Qingzhou Paper Mill with an annual output of more than 200000 tons, 9 with an annual output of more than 100000 tons, about 130 with an annual output of more than 30000 tons, 242 with an annual output of more than 10000 tons, and 9838 with an annual output of more than 10000 tons (including 9141 with an annual output of less than 5000 tons), and the output of less than 10000 tons accounts for about 60% of the country. The average scale of 11025 paper-making enterprises is more than 2000 tons per year. In accordance with the principles of "we can't develop production at the expense of the environment", "we should act if there are orders, stop if there are prohibitions" and "we must abide by the laws", what should we do in the face of so many small paper mills

many experts proposed to expand the scale, concentrate pulping and disperse papermaking, so as to adapt to the economic scale of alkali (waste liquid) recovery. After decades of efforts, countless experiences and lessons have been learned. Especially in recent years, considerable progress has been made in large pulp mills (especially wood pulp mills) and medium-sized pulp mills. Some have achieved obvious environmental and economic benefits. Pulp mills with an annual output of more than 17000 tons are strengthening pollution control and implementing alkali (waste liquid) recovery projects as soon as possible. Most of the "pulp and paper conservation" with an annual output of about 10000 tons, which cannot be expanded at the moment, use commercial pulp and waste paper (including waste paper deinking). These paper mills with a capacity of more than 10000 tons are technologically advanced in China, and their products are relatively high and medium-grade in China. What about the many small factories with 10000 tons and 5000 tons already built? Centralized pulping and utilization of waste paper are still difficult to meet the emission standards, and the prospect is not optimistic

in the face of the severe situation, two young comrades, Chen Wenchuang and Chen Wenzhong, after eight years of efforts and repeated trial production, finally developed a paperboard laminating machine. At the Sixth China patent new technology and new products Expo hosted by the State Patent Office of the people's Republic of China in 1997, the cutting speed in drilling processing will not have a great impact on the cutting force and won the Gold Award. The machine can combine two kinds of paper or paperboard with adhesives to form various paperboards, such as composite white paperboard, carton board, high-strength Kraft linerboard, gold foil and silver foil. At the scene, we saw that 60 g/m2 single-sided offset paper and 240 g/m2 thick ordinary corrugated base paper were compounded into 1600 mm wide and 305 g/m2 white paperboard, which was very flat, just like the coated white paperboard, which surprised many papermaking experts and users. In the whole production process, only tap water is used for boiling glue, and there is no water at all, no drainage, and no pollution at all. The composite cardboard equipment with a width of 1600 mm uses only 20 watts of electricity, and there is no noise. It can be compounded into paperboard with a ration of more than 600 g/m2, and the output of composite paperboard is 6 ~ 20 tons/day (the ration of base paper is small and the output is low, which is the output of 200 ~ 600 g/m2 composite paperboard). As the main treatment machine, the recycled plastic granulator that evaporates the glue will have a large customer base. The agent contains a little water and consumes little energy (steam, coal, electricity) (30 kg of coal is consumed for the product based on coal)

the paperboard laminating machine can use different grades of two kinds of paper or paperboard to complement each other, so as to significantly improve the product quality and performance at the most reasonable low cost. For example, use Kraft packaging paper or cement bag paper with high strength (such as folding strength) to compound with hardwood semi chemical pulp board with low folding strength (only 1-6 times) and high ring compression strength and stiffness. The strength and service performance of the composite board can be comparable to grade B high-strength kraft board. In 1996, China imported 1.0161 million tons of this kind of kraft board, and the import volume in 1997 was much higher than that in 1996, which shows its great market potential. Calculated according to the current market price in Liaoning Province: kraft paper is 5200 yuan a ton, with a ration of 70 g/m2, and 285 g/m2 after compounding (an increase of 5 g/m2 is the weight gain of adhesive), then its cost (calculated by a ton of product):

kraft paper 70/385=18.18% × 5200=945.45 yuan

carton board 310/385=80.52% × 2700=2174.04 yuan

Coal 30kg/ton product 6.0 yuan

electricity 10 kwh 6.7 yuan

adhesive 80.0 yuan

labor (4 people per shift) 73.3 yuan

Tax (calculated by 10% of output value after deducting input tax) 40.0 yuan

total cost 3325.49 yuan

selling price (much lower than imports) 4000.0 yuan

profit 674.51 yuan

If 60g/m2 single-sided offset paper is used, Shenyang 5000 yuan/ton, and thick ordinary corrugated base paper, the quantitative quantity is 240g/m2, Shenyang 1500 yuan/ton, to compound the production of white paperboard, per ton product cost:

single sided offset paper 60/305=19.67% × 5000=983.6 yuan

thick ordinary corrugated base paper 240/305=78.68 × 1500=1180.3 yuan

electricity, labor 80.0 yuan

Coal 30kg/ton product 6.0 yuan

adhesive 80.0 yuan

Tax (calculated by 10% of the output value after deducting the input tax) 28.0 yuan

total cost 2357.9 yuan

selling price 2800 yuan

profit 442 yuan

it can be seen that the paperboard laminating machine is a new project with low investment, energy saving, pollution-free and high profit. At present, many paper mills are shut down and change production to meet the needs of the packaging industry, It will be a very feasible new way suitable for China's national conditions

(author Luo shaochu, chief engineer of Liaoning Papermaking Research Institute)

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