Method for resource utilization of sludge biochar

Abstract

The invention discloses a method for resource utilization of sludge biochar. Comprising the following steps: performing fine grinding and magnetic separation on biochar prepared from sludge to obtain a ferromagnetic material and biochar micro powder without iron; wherein the charcoal micro powder, the cement and the early strength agent are subjected to dry premixing to obtain a premix; then adding river sand and mixing to obtain a secondary mixture; uniformly dispersing a water reducing agent and water in a stirrer, and adding the secondary mixture to obtain a third mixture; feeding into a mold for pressure forming; placing the mold in a steam curing box, cooling to room temperature after steam curing, and removing the mold after the green body is solidified; and curing at normal temperature to obtain concrete solid bricks, building blocks or thermal insulation materials. According to the method, harmful heavy metal in the sludge is solidified, secondary pollution to the environment is avoided, the concrete solid brick is directly prepared, resource utilization and large-scale treatment of the sludge are achieved, and the method is particularly suitable for treatment of biochar obtained through pyrolysis of the sludge containing the heavy metal. The method is simple in process and low in cost, and has good economic and environmental benefits.

Description

technical field [0001] The invention relates to the field of comprehensive utilization of solid waste resources, in particular to a method for resource utilization of sludge biochar. Background technique [0002] Although sludge contains potentially useful organic matter and nutrients such as N, P, and K, the direct entry of salt, pathogenic microorganisms, organic polymers, and especially heavy metals into the environment will cause air, water, and soil pollution. The study found that the larger the city, the higher the concentration of heavy metals in the sludge. Heavy metals in sludge in my country have obvious regional characteristics. For example, coal-fired heating is more common in the north, so the content of As and Hg is higher; the distribution of non-ferrous metal mining areas in the south is concentrated and the degree of human development is higher, so the content of Cr, Ni, Cu, Zn, Cd, and Pb is higher. At present, the problem of high heavy metal content in s...

AI Technical Summary

Problems solved by technology

The above methods all need to remove some heavy metals from the sludge by leaching, then plate and frame filter, then add fly ash or blast furnace slag, mix and granulate, dry, and then crack at high temperature for 3 to 4 hours to obtain sludge biochar. This sludge biochar The preparation process is complicated and the applicability is poor; moreover, waste fabrics need to be added in the brick making process, which makes the whole process cost high and the application is limited

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