Environmentally-friendly paper making and pulping technique and system with high yield

Abstract

The application of the invention provides an environmentally-friendly paper making and pulping technique with high yield, which comprises a raw material preprocessing stage, a physical fibrillation impregnating processing stage, an impregnating, steaming and bleaching three-section integrated pulping stage and a thickening and dewatering processing stage. An environmentally-friendly paper making and pulping system with high yield realizing the pulping technique comprises a stock cutter, a hammering and fibrillation screening dust remover, a washing dust remover, dewatering conveying equipment, a spiral steaming conveyor, a crashing, extruding and impregnating machine, a stirring and impregnating cabin, a pump pipe and a discharge pipe of a high-enriched steaming, bleaching and pulping all-in-one machine, wherein the pump pipe is connected to the high-enriched steaming bleaching pulping all-in-one machine; the discharge pipe of the high-enriched steaming, bleaching and pulping all-in-one machine is connected to a pulp cabin; the pump pipe of the pulp cabin is connected with a thickening and dewatering machine; the thickening and dewatering machine is output to the high-enriched pulping machine; the output of the high-enriched pulping machine is connected with a screening purifier and a thickening and squeezing machine in sequence. In the invention, the problems of high pollution, high energy consumption, serious shortage of paper making raw material and the like in present pulping and paper making industry can be solved fundamentally; rich plant fiber in the nature can be used, and the technical purposes of efficient bleaching, high yield, no black liquor and low energy consumption can be realized.

Description

technical field [0001] The application of the present invention relates to a papermaking pulping process method and its process system, especially a papermaking pulping process method and system composition suitable for annual non-wood fiber grass and crop straw plant raw materials. Background technique [0002] Plant raw materials for paper pulping applications include cellulose, hemicellulose, lignin, and pectin. Compared with woody plants, annual non-woody fiber grasses and crop straws have many fine fibers, high silicon content, large ash content, high pentose content, and many non-fibrous components such as miscellaneous cells. The color is dark, the lignin structure is complex and the content is high, and the content of lignin and its derivatives can reach 30-60%. It is considered as a component of no use value in the paper pulping industry. The lignin and its derivatives must be removed. [0003] The existing paper pulping technology generally has technical problems...

AI Technical Summary

Problems solved by technology

Cooking under high alkali, high temperature and high pressure conditions, the conventional strong alkali dosage is 8-18% of the weight of plant raw materials, the cooking temperature is 155-185°C, the pressure reaches 0.6-0.8MPa, the lignin dissolved in the cooking waste liquid is alkaline Lignin exists in the form of high silicon content, which leads to high viscosity and dark color of cooking waste liquid, which increases the difficulty of bleaching, evaporation concentration and alkali recovery. More cellulose is degraded and lost, resulting in a large amount of sewage in the cooking, washing, and screening processes, and the concentration of suspended solids and organic matter in the sewage is high, high viscosity, high alkali, dark color, poor biodegradability, and large fiber loss

The pre-cooking process and the process between cooking and bleaching in the existing alkaline pulping process have almost no correlation with the core cooking and bleaching process. They just do some simple physical cutting and cleaning for the core process, and the technical pressure is all Concentrate on the cooking process, so it is difficult to take into account the multi-faceted technical requirements

The alkali recovery technology in the above-mentioned pulping process is relatively mature for woody paper pulping black liquor, but there are great technical obstacles for herbaceous paper pulping black liquor. The reason is that the straw pulp waste liquor High silicon content, high viscosity, and poor filterability. When the lime alkali recovery method is used, high silicon content will significantly reduce the availability of active lime. Moreover, the fluidity is poor, it is difficult to transport, and it will also cause scaling problems in the delivery pipe.

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