Study On Preparation And Application Potential Of Kitchen-based Biomass Carbon

With the development of society and economy,the production materials have gradually satisfied people's normal living needs,and people's living standards have been increasing.In particular,the demand for diet has become higher and higher,and the catering industry has also developed rapidly.However,the environmental problems caused by the kitchen waste have become more and more serious,causing serious problems for people's daily life.And with the shortage of resources,the resource utilization of kitchen and kitchen residues is particularly important.Therefore,this paper relies on the current serious environmental pollution problems,especially the problem of heavy metal pollution,using the kitchen waste as the main raw material,through the anaerobic pyrolysis method to prepare environmentally friendly environmental repair materials.Provide new ideas to solve the current serious environmental problems.Although the existing research has a lot of pyrolysis of kitchen waste,there is very little research on the preparation of biomass charcoal for kitchen waste,and there is a lack of physical structure after the pyrolysis of the kitchen residue.The study of chemical characteristics and applications in the field of environmental remediation is not known to the environmental hazards of heavy metals enriched in kitchen waste.Therefore,this paper carried out research on the preparation of biochar by pyrolysis of kitchen waste,and introduced peanut shell charcoal and corn stover charcoal to discuss its applicability and effectiveness in the environment.The main findings of this paper are as follows:(1)Preparing the kitchen-based biochar at different temperatures,and extracting the heavy metals in the biochar by the improved BCR method,and when the pyrolysis temperature rises to 400?,the kitchen-based organisms More than 90%of the heavy metals in the carbon exist in the form of residual state.According to the ecological risk assessment of the kitchen-based biochar,the ecological risks of heavy metals in KBC400,KBC500 and KBC600 are at a low level.(2)The Langmuir isotherm adsorption model was used to evaluate the adsorption capacity of bio-charcoal for heavy metal Pb2+.KBC400 has the strongest adsorption capacity for heavy metal Pb2+ due to its high ash content,pH and surface-rich functional groups.The adsorption capacity is as high as 149.2 mg/g.Therefore,from the perspective of energy consumption,the ecological risk of heavy metals in the bio-charcoal and the adsorption capacity of heavy metals,it is considered that KBC400 is more suitable as a new environmental remediation material and is the main target of subsequent research.(3)Biochar was prepared by treating peanut shells,corn stover and kitchen residue under the same conditions.The heavy metals Pb2+ and Cd2+were used as the target pollutants.The adsorption behavior of three biochars in aqueous solution was studied by static adsorption experiments in aqueous solution combined with isothermal adsorption model and kinetic model.It was concluded that the three biochars were consistent with Langmuir.Both the isothermal adsorption equation and the quasi-second-order kinetic equation,R2 are greater than 0.99.And the adsorption effect of three biochars on heavy metals Pb2+ and Cd2+is best in KBC400,followed by YBC400 and PBC400.(4)KBC400,YBC400 and PBC400 were added to the soil to study its effect on heavy metals in the soil.The extraction of heavy metals in the soil by the improved BCR method revealed that the heavy metals in the soil were reduced to different degrees by the exchangeable state(F1+F2)compared with the control group.The residual state(F4)is elevated.And using EDTA,HCl to extract heavy metals from the soil found that the bioavailability of heavy metals in the soil was greatly reduced,and the heavy metals in the soil extracted by the TClP experiment were lower than the limits specified in the TCLP.It is concluded that the fixation effect of three biochars on heavy metals Pb and Cd is best in KBC400,followed by YBC400 and PBC400.(5)Pot experiments showed that the addition of three biochars,KBC400,YBC400 and PBC400,can reduce the damage of heavy metals to plants and increase the biomass of plants.The content of SOD and POD in plants decreased with the addition of three kinds of biochar,and the content of chlorophyll gradually increased.Among them,KBC400 is the most effective,followed by YBC400 and PBC400.