Biomass fuel based on sludge, straw and raw coal, preparation method of biomass fuel and application of fuel slag

Abstract

The invention discloses a biomass fuel based on sludge, straw and raw coal, a preparation method of the biomass fuel and application of a fuel slag, and belongs to the field of resource utilization of solid waste. The biomass fuel is formed by mixing, pressing and molding the sludge, the straw and the raw coal; and the weight ratio of the sludge, the straw and the raw coal is (1-3): (1-3): 3. The preparation method comprises the following steps of: adding limestone to the dehydrated sludge subjected to application of an aluminum coagulant, wherein the mass percentage of the limestone in the sludge is 1 to 3 percent; mixing the sludge and the straw to aerobically compost; mixing the raw coal with the mixture of sludge and straw, pressing and molding to obtain the biomass fuel. After the biomass fuel disclosed by the invention is burnt, the maximum absorption capacity of the slag exceeds 25g / Kg and can be used as substitutes of filler materials for artificial wetlands. According to the biomass fuel based on sludge, straw and raw coal, the preparation method of the biomass fuel and the application of the fuel slag, water in the raw material can be hydrated quickly, heavy metals can be passivated, the emission of SO2 in combustion of the raw coal can be reduced, and the burnt slag of the biomass fuel has high contents of calcium, aluminum and Ferrum with strong absorption capacity to phosphor and can be used as a phosphorus removing agent during sewage treatment.

Description

technical field [0001] The invention belongs to the technical field of resource utilization of environmental protection solid waste, and more specifically relates to a biomass fuel based on sludge-straw-raw coal and a preparation method thereof, as well as the application of slag after combustion of the biomass fuel. Background technique [0002] With the increasing service level of municipal facilities in modern cities and the increase of urban population, the discharge of urban domestic sewage is also increasing, resulting in the generation of a large amount of sludge in the process of urban sewage treatment. Sewage sludge is a heterogeneous body composed of organic debris, microorganisms, inorganic particles, colloids, etc. Sludge contains toxic organic matter, pathogenic microorganisms and heavy metals, which will cause serious harm to the environment. With the rapid increase in sludge production The disposal of sludge has attracted more and more attention. [0003] The...

AI Technical Summary

Problems solved by technology

[0009] The present invention aims at the problems that in the existing sludge-straw-raw coal mixed combustion technology, the raw material dehydration time is long, heavy metals may be leached during transportation, and the slag cannot be utilized as a resource, and a sludge-straw-raw coal based Biomass fuel and its preparation method, the present invention screens specific sludge, and by adding a small amount of quicklimestone for sterilization and dehydration, using straw and sludge mixed compost to initially reduce the moisture content, straw degraded humus passivation and quicklimestone meet water to produce Oh - It can solidify the heavy metal content in the sludge, which is beneficial to the storage and transportation of the sludge-straw mixture; the sludge-straw mixture is then mixed with raw coal and pressed into shape, and the CaO and Al in the sludge are coordinated after adding quicklime. 2 o 3 , Fe 2 o 3 And the characteristics of high NaCl content can be solidified to reduce SO in the process of mixed fuel incineration 2 release, and the high content of Ca, Al and Fe in the slag after combustion improves the phosphorus adsorption capacity in the sewage, so that the fuel slag can be used as a phosphorus removal agent in the sewage treatment process or as a constructed wetland filler

Images