Treatment and recycling technology of white water in production of paper-making reconstituted tobacco

Abstract

The invention discloses a treatment and recycling technology of white water in the production of a paper-making reconstituted tobacco. The technology comprises the following steps of: flocculating the white water at a wet part in a production process of the reconstituted tobacco substrate by adding in a flocculating agent, carrying out precipitation pretreatment, filtering clear white water pumped from a clear white water tank by using a multi-disc filter with a self-purification function, causing the ultra-clear white water after the filtration to be collected in an ultra-clear white water tank for storage to prepare for recycling, and returning the automatically discharged solid content in the filtration process to a tapered sedimentation tank. The technology is very applicable to the continuous treatment of the white water in the production process of the reconstituted tobacco substrate, free from back flush, low in treatment cost, good in treatment effect, and 70-80% in solid content removal rate, the ultra-clear white water after the treatment can completely replace clear water to be reused for screen washing, low-pressure spraying and screen edge sealing, the removed solid content dreg can be added into a slurry according to a proportion, waste water drain is reduced, environment protection pressure is relived, raw materials are saved, and economic benefit is obvious.

Description

technical field [0001] The invention relates to a white water treatment and reuse process in the production of reconstituted tobacco leaves by the papermaking method. Specifically, the wet part white water in the process of making reconstituted tobacco leaf substrates is flocculated and pretreated by adding a flocculant and then pretreated by a multi-disc filter. The ultra-clear water is filtered out deeply, and it can be used instead of clean water for net washing, low-pressure spraying and net edge sealing, which belongs to the technical field of reconstituted tobacco leaf production in the cigarette industry. Background technique [0002] The production of reconstituted tobacco leaves (also known as tobacco flakes) by the wet papermaking method is the same as the traditional papermaking industry. It is a major water and water polluter, especially the pollution of water sources. At present, many papermaking enterprises are treating the sewage discharged from the paper machi...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the white water treatment and reuse of the traditional papermaking production line, in the published technologies, patents or literatures at home and abroad, there are treatment methods such as adding coagulant aids, drum filtration or ultrafiltration, air flotation, and multi-disk recovery. Due to the single composition of pulp fibers , high purity, simple and efficient white water treatment methods, such as the Chinese utility model patent "Papermaking White Water Separator" (application number: 91207603.8) equipment for recovering fibers, fillers and clean water from white water in the paper industry, which is characterized by mixing white water into a small amount of flocculation Coagulant and in the form of pulse flow, after uniform water distribution, solid-liquid separation occurs in the settling chamber, so that fibers and fillers are output from the lower part of the separator, and clear water is overflowed from the upper part. This separator is used to treat white water and recover fibers and fillers. The rate can reach more than 99%, but using this equipment alone to recover white water in the reconstituted tobacco leaf production line cannot achieve a recovery rate of more than 60% for tobacco fibers, outer fibers and fillers; the invention patent "A Papermaking White Water Treatment and Reuse Process" (application No.: 200610122128.0) The steps are: A. send papermaking white water to primary treatment to remove most of the fibers and impurities in the white water; The production water enters the papermaking system, C backwashes the disc filter, and the backwash water returns to the white water tank for initial treatment. The disadvantages are: (1) This process is mainly used in large paper mills, and the cost of equipment used is high and the operating cost is high. High, not suitable for small-scale reconstituted tobacco production lines with an annual output of 20,000 tons or less; (2) In view of the fact that fine fibers and non-fibrous components in the reconstituted tobacco pulp raw materials account for the majority, the plastic sheet filter is easy to block the filter when it is used, which will inevitably cause adverse reactions. The washing frequency is high; (3) a large amount of tap water is required for backwashing, which reduces the white water treatment efficiency; the process adopted in the invention patent "Papermaking White Water Treatment Method" (application number: 200410086580.7) is similar to the above-mentioned "A Papermaking White Water Treatment and Reuse Process" The difference is that the ultrafiltration treatment is carried out on the air flotation water. The filter membranes used include polysulfone, polyacrylonitrile, polyvinylidene fluoride or cellulose acetate ultrafiltration membranes. The disadvantage is that it needs to be backwashed with tap water. membrane; the invention patent "A White Water Reuse Process for Papermaking System" (Application No.: 201010582965.8) does not involve the white water recovery device and recycling technology; the new patent "A Batch-type Papermaking White Water Treatment System" (Application No.: 01234166.5) is a combination of multiple circular tanks, and its recovery effect of fibers and fillers is similar to that of "White Water Separator for Papermaking" (application number: 91207603.8)

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