Organic fertilizer prepared from papermaking black liquor produced in alkaline pulping process and preparation method of organic fertilizer

Abstract

The invention discloses an organic fertilizer. The organic fertilizer is prepared from papermaking black liquor produced in an alkaline pulping process. According to the preparation process of the organic fertilizer, the difficult-to-treat black liquid generated in the pulping process is fully utilized, so that the pollution problem in the pulping process is solved from the source, the environment-friendly chemistry standard is realized, organic matter and inorganic elements in the black liquor are effectively utilized, and the prepared fertilizer meets the national standard. The organic matter content of the pulping black liquor is stable, the requirements of various nutrient elements in the fertilizer can be met, and the utilization rate of the black liquor is high. The prepared fertilizer is high in fertilizer efficiency and balanced in nutrition and is suitable for plant growth, wherein the organic matter contained in the fertilizer can effectively improve physical, chemical and biological characteristics of soil, and the soil can be cured.

Description

technical field [0001] The invention belongs to the technical field of fertilizers, and in particular relates to an organic fertilizer prepared from papermaking black liquor produced by an alkaline pulping process and a preparation method thereof. Background technique [0002] Paper is an important item closely related to human life. It has developed into a raw material for packaging, printing, cigarettes, stationery, machinery, building materials, military industry and other industries. The paper industry has a wide range of applications in all walks of life. The development of the paper industry directly It reflects the level of a country's national economy and civilization construction. my country is a big country for papermaking and papermaking, and papermaking has become an important basic industry that drives the development of the national economy. According to China's 2015 Paper Industry Annual Report, in 2015 there were about 2,900 paper and cardboard manufacturers...

AI Technical Summary

Problems solved by technology

[0003] The traditional papermaking process is to process the papermaking raw materials through pulping, modulation, papermaking, processing and other main processing steps. Among them, pulping is the first step and the most critical step in papermaking. The pulping process is to remove the pulping raw materials. The process of lignin; the removal process is mainly divided into chemical pulping method, mechanical pulping method and semi-chemical pulping method. Chemical pulping method is the most widely used production method. The above high-temperature steam device continuously cooks the tablet, so that the lignin in the pulping raw material reacts with chemical reagents at high temperature to produce water-soluble matter, which is separated from the fiber into a slurry; chemical pulping retains the natural length of the fiber and removes Most of the lignin is removed, but the pulp yield is low and the pollution is large. In addition, during the cooking process, due to the addition of chemicals, the prepared pulp has an unpleasant smell and a bitter taste. And during the washing process, a large amount of black liquor will also be produced

[0004] Black liquor contains a large amount of suspended solids, organic pollutants and toxic substances, of which about 30-35% are inorganic substances, and the main components are sodium hydroxide, sodium carbonate, sodium sulfide, sodium sulfate and other sodium salts combined with organic substances ; It also contains 65-70% organic substances, the main components are lignin, resin, starch and low-molecular compounds, etc. If the black liquor is directly discharged into the water body, it will cause serious pollution, such as containing a large amount of fiber, pigment and inorganic Salt papermaking wastewater will turn the water black and have a special stench; the biochemical oxygen demand (BOD) of papermaking black liquor containing high concentrations of organic pollutants can be as high as 5000-40000g / L, which will consume a large amount of dissolved water. Oxygen affects the water quality; a large amount of alkaline substances in the black liquor will cause the pH value of the water to rise sharply and destroy the balance of the water environment

Traditional alkali recovery technology equipment is complex and requires a large amount of investment. It is reported that a set of alkali recovery equipment generally requires an investment of more than 30 million yuan, and its daily operating costs are also relatively high. It is as high as 2671 yuan / ton of alkali, while the market price of sodium hydroxide is only 1800 yuan. Therefore, most of our enterprises are unable to carry out alkali recovery at present, but directly discharge the black liquor or directly discharge it after dilution, causing environmental pollution, especially in water areas. extreme pollution

[0005] At present, there are relevant reports on the preparation of fertilizers from papermaking black liquor, and they have not been effectively promoted. Not only that, but there are also some problems in these technical solutions: (1) the cost is high; (2) the quality of the prepared fertilizer is poor , poor fertilizer efficiency; (3) it is necessary to add other nutrient sources, and its consumption is equivalent to that of fertilizers prepared by other methods in the prior art; (4) there are few utilization methods and a single variety