| In order to achieve the resources of turmeric diosgenin waste residue and extendthe industry chain of solid waste comprehensive utilization, the subsequent use effectand mechanism of turmeric diosgenin waste residue as raw material preparation ofbiochar was discussed. The research results would provide basic data to enrich thetheory and application of biochar and is theoretical and practical guiding significanceto the industrialized production of biochar.This research mainly has two aspects: First of all, static and dynamic adsorptionexperiment was carried out respectively with the biochar preparation of turmericdiosgenin waste residue as adsorbent. The factors, such as influence of time,temperature, initial concentration, biochar dosing quantity and hunting speed, on theeffect of biological carbon adsorption of methylene blue were investigated by staticadsorption experiments with methylene blue solution as the test sample. And theorthogonal experiment was used to the optimize the experimental conditions. Finally,the adsorption isotherm fitting and the mechanism of adsorption kinetics wereexplored. In the dynamic adsorption experiments, Pb2+solution was used to simulateheavy metal waste water, that flowed through the self-made biological carbonadsorption column at a certain velocity by changing the biochar addition amount,initial concentration of Pb2+, flow rate of wastewater and pH value respectively anddrawing the breakthrough curve under different conditions to study the biologicalcarbon adsorption dynamics model for Pb2+by Thomas and Yoon-Nelson model.Meanwhile, in order to review the preliminary effect of fertilizer maintenance, theabove biochar and biochar slow-release fertilize were filled respectively into sandyand soil by using the self-made leaching device, and initial dissolution rate （24h）and the cumulative release rate soil nutrient elements were measured separately.The experiment results show that:（1）The adsorbing capacity of methylene blue onto biochar increase rapidly asinitial concentration, temperature, time and hunting speed extended and decrease asbiochar dosing quantity extended. Adsorption rate increase rapidly as biochar dosingquantity, temperature, time and hunting speed extended and decrease as initialconcentration extended.（2）The static adsorption experiment data can be better to conform toFreundlich．Theory of equilibrium adsorption quantity and the actual equilibriumadsorption quantity are basically identical. Freundlich parameter value1/n is0.21,between0.1~0.5, meaning that is easy to absorption, and KF6.58L/g, meaning that isthe uneven surface adsorption. Theoretical equilibrium absorption capacity isconsistent with the actual equilibrium adsorption capacity. Methylene blue ontobiochar accords with the second order equation．Theory of equilibrium adsorptionquantity and the actual equilibrium adsorption quantity are basically identical. Itshows that the adsorption is a rate controlling step chemically. （3）The penetration time increase as biochar dosing quantity extended, anddecreasing rapidly as the initial concentration and flow rate increased. The higher thepH value, the longer penetration time. The penetration time remained unchangedbasically when the pH value is greater than4.（4）Thomas and Yoon-Nelson model can well describe the dynamics of biocharon Pb2+adsorption data, and is able to accurately predict adsorption quantity and50%penetration time respectively.（5）The early dissolution rate and the accumulative release rate of nitrogen andphosphorus of sand and soil were increased with the increasing amount of biochar.（6）Both initial dissolution rate and cumulative dissolution rate of biocharslow-release fertilizer for sand and soil are reduced.（7）The slow-release effect of biochar slow-release fertilizer on nutrients isbatter than biochar in the horizontal comparison of them. |
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