Treatment method of paper pulp biological sludge

Abstract

The invention relates to a treatment method of paper pulp biological sludge. According to the method, the paper pulp biological sludge is successively subjected to the following steps of collecting biological sludge and carrying out auxiliary coagulation, pre-dewatering and separating, preheating and then mixing with a back liquid for multiple-effect evaporation and carrying out super concentration and evaporation on biological sludge-back liquid, and finally mixing and burning in an alkali furnace for generating electricity and supplying heat, and causticizing fusant and then recycling the causticized fusant. According to the invention, solid biological sludge wastes are turned to wealth, so that a pulp plant reaches zero emission, thereby achieving clean production and energy saving andemission reduction, reducing garbage landfill and being beneficial to development of circulating economy. The method has novel technology and achieves a 3R (reduce, reuse and recycle) target initiated by international clean production.

Description

technical field [0001] The invention relates to the field of environmental protection, in particular to a method for treating pulp and paper biological sludge. Background technique [0002] At present, in the sewage treatment of domestic and foreign bleached kraft pulp mills, most of the primary sludge and biochemical treatment sludge produced are mixed landfill or a small amount of sludge is composted, which inevitably leads to a large amount of land occupation and even produce secondary pollution. [0003] According to the statistics of China Paper Association, in 2010, the total output of paper and paperboard in China was 92.7 million tons, the consumption was 91.73 million tons, and the remaining wet sludge generated by the whole industry was about 9-10 million tons. With the development of the national economy and the improvement of people's living standards and quality, the production and sales of pulp and paper will also increase, and the requirements for the surroun...

AI Technical Summary

Problems solved by technology

Biological sludge contains a large amount of organic matter, is viscous, and is difficult to dehydrate in depth. Therefore, mixed treatment and landfill will only increase a large amount of additional freight, and incineration requires additional fuel to remove water. It is very difficult technically and economically. At present, there is no slurry that can operate stably at home and abroad. Paper sludge incinerator

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