Automatically maintained and automatically controlled long-term safe operation device for concentrating paper pulp-washing black liquor

Abstract

The invention discloses an automatically maintained and automatically controlled long-term safe operation device for concentrating paper pulp-washing black liquor. The device comprises a reverse washing device and a peripheral mechanism, wherein the reverse washing device is vertically enclosed, and composed of a plurality of stages of squeezing and mixing replacement mechanisms connected up and down end to end and an automatic maintenance and preservation system; each stage of squeezing and mixing replacement mechanism consists of a housing, a squeezing cabin arranged inside the housing, a large base plate connected with the housing and a uniform mixing replacement cabin, and the automatic maintenance and preservation system comprises a pulp operation state sensor, and an automatic injection system of butter, gear oil and dynamic seal assembly lubricating oil. Organic matters in paper pulp are effectively separated out, and the waste liquid is effectively concentrated, so the extraction rate of the black liquor is up to over 99% and the concentration exceeds 16%; the water consumed for washing per ton of absolute dry fiber pulp is less than 9t, so the water is saved and the pollution is removed; the environmental protection is facilitated, and the alkaline recovery rate is up to over 98%. The energy source which is 1-1.5times that of papermaking energy consumption can be converted and generated, and the device can be automatically preserved and maintained, so the device can safely operate for a long period of time without a fault and is high in work efficiency.

Description

technical field [0001] The invention relates to a pulp washing equipment for papermaking, in particular to a pulp washing black liquor concentration equipment with automatic maintenance and automatic control for long-term safe operation. Background technique [0002] In the paper industry, the usual method for washing pulp is to perform multiple squeezes and reversely use the waste liquid with poor concentration to diffuse and replace the high-concentration waste liquid in the fiber. In the pulp washing process, there are many types of washing equipment that are often used. The original static pressure washing tank is used to wash the pulp with a large amount of water to replace the non-cellulose substances such as lignin, hemicellulose, ashes and pectin. etc. The water consumption per ton of pulp reaches more than 300 tons; there are mechanical equipment such as screw presses, counter-roll presses, and other pure extrusion methods for pulp washing. These are all single-mach...

AI Technical Summary

Problems solved by technology

In the pulp washing process, there are many types of washing equipment that are often used. The original static pressure washing tank is used to wash the pulp with a large amount of water to replace the non-cellulose substances such as lignin, hemicellulose, ashes and pectin. etc. The water consumption per ton of pulp reaches more than 300 tons; there are mechanical equipment such as screw presses, counter-roll presses, and other pure extrusion methods for pulp washing. These are all single-machine operations, and the water consumption is very high There is also a three-machine combination pressure washing machine for pulp washing. Although it is reverse washing, it is not easy to keep warm, and it is easy to immerse air to produce saponification foam, which will affect the production environment and bring trouble to production.

In short, the above-mentioned pulp washing methods all exist, and the washed pulp needs to be cleaned in the later stage. In the cleaning process, a large amount of low-concentration mid-stage wastewater will be generated, and the water consumption of washing one ton of pulp is large, which can reach more than 250-300 tons. During the period, the extraction and concentration rates of black liquor are low, which will also cause a large workload and high cost of sewage treatment

[0003] In addition, an invention called "Pulp Washing Black Liquor Concentrator" has been disclosed in the Chinese Patent Gazette, and its patent number is: 200520031809.7. Although it can wash pulp and concentrate black liquor, it cannot realize the process of washing pulp. For the automatic control and maintenance of the equipment, the equipment needs to be shut down for overhaul after working for a period of time, so it is difficult to improve the production capacity of the equipment

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