Discussion on the technological conditions of alka

2022-09-23
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Discussion on the technological conditions of bamboo alkaline hydrogen peroxide pulping

alkaline hydrogen peroxide method (AHP) is an alkali free cooking method. The components of its cooking liquid are NaOH and hydrogen peroxide. Because there is no sulfide in the cooking liquid, there is little or no odor gas emission during the cooking process, which reduces the big gas pollution. At the same time, there is no sulfide generation in the cooking process. Its cooking waste liquid can adapt to the new sulfur free waste liquid alkali recovery process currently developed

based on the principles of reducing consumption, pollution and energy saving, taking kraft paper made from bamboo pulp as an example, the optimal technological conditions of bamboo slice AHP cooking were discussed, which provided some theoretical basis for bamboo slice low pollution pulping

1 experiment

1.1 experimental raw materials

take Neosinocalamus affinis as raw materials, prepare materials manually and remove sediment and debris 5 The lifting rack and oil cup of the fatigue testing machine should often be filled with impurities such as lubricating oil, and then put into a plastic bag to balance the water for standby

1.2 process flow

bamboo slices warm water (about 50 C), washing hot water (about 95 C), pre impregnation (except air), cooking, washing, screening, washing, pulping and tablet making

1.3 experimental method

pulping: cooking is carried out in zqs1 type 15L electric rotary cooking pot. A flat screen with a screen gap of 0.3mm is used for slurry screening

beating and determination of beating degree: PFI mill is used for beating, with pulp concentration of 10% and beating gap of 0.3mm. The pulp is copied from the paper reader. The beating degree and physical strength of pulp chips were measured according to the information standard method from the 6th executive director (expanded) meeting of the 5th session of the China Industry Association held on July 28

Results and Discussion on how to solve the "import dependence" in the new material industry

the preliminary experimental exploration in the early stage shows that the factors affecting the bamboo slice AHP cooking include the amount of NaOH, the amount of hydrogen peroxide, the maximum temperature, the holding time at the maximum temperature, the liquid ratio, and the heating time. Among these factors, the liquid ratio and the heating time have little influence, and they are positioned at 1:3 and 160min respectively, while other factors are discussed. During the experiment, the cooking curve was fixed so that the cooking temperature increased from room temperature to 130 C within 120min, and the temperature was kept at 130 C for 40min, and then the temperature increased from 130 C to the maximum temperature within 40min, and the temperature was kept at 130 C until the end of the reaction

according to the experimental data and analysis, the optimized process conditions are as follows: the amount of alkali used is 18%, the amount of hydrogen peroxide is 35, the holding time at the maximum temperature is 60min, and the maximum temperature is 165 C. Under this condition, the verification experiment was carried out. The results showed that the yield of fine slurry was 46.78%, the bursting index was 3.96kpa m2/g, the tearing index was 10.67mn m2/g, the folding resistance was 753 times, the fracture length was 6.38km, and the kappa value was 55.1. All of these achieved ideal results and verified the correctness of the optimized process

the technological conditions of bamboo kraft pulping (kraft paper production) are determined by referring to a factory as follows: alkali consumption 15%, degree of vulcanization 23%, maximum cooking temperature 160 C, holding time 60min under the maximum cooking temperature, liquid ratio 1:2.8. After the sulfate cooking experiment, a strong pungent odor is emitted when the cooking pot is opened, while almost no odor is emitted by the alkaline hydrogen peroxide method. According to the experimental data, AHP pulp has higher bursting index, tearing index, folding resistance and fracture length, which is equivalent to KP pulp, and the yield of fine pulp is 1.81% higher than KP pulp. The wastewater pollution load of AHP pulping is lower than that of KP pulping, in which BOD5 is reduced by 27.5% and CODcr is reduced by 17.1% compared with KP pulping. The reason is that as more enterprises begin to pay attention to the sustainable development, AHP pulping is sulfur free pulping, and there are no reducing organic substances such as sulfurized lignin in the waste liquid, and the yield of fine pulp is higher than that of KP pulping, indicating that cooking is more uniform and carbohydrate loss is less, so the pollution load is low. The above results show that the sulfur free cooking of bamboo chips can not only meet the needs of physical strength of pulping, but also reduce the emission of odor gas and the pollution load of water, protect the environment, and achieve the purpose of clean pulping

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