Functionalization And Performance Of Livestock Manure Biochar On Plateau

Due to the rapid development of animal husbandry,the amount of livestock and poultry manure has greatly increased.On the basis of conventional feed,energy,fertilizer and other treatment methods,it is necessary to seek new treatment strategies to solve the problem of livestock and poultry manure and increase its additional value.Biochar is an important way for the utilization of biomass wastes.Through this method,it can not only kill pathogenic bacteria and solidify heavy metals through high temperature,but also make it into a good charcoal material.Compared with traditional manure treatment methods,plateau livestock manure biochar has the advantages of environmental protection and renewable,and it is very necessary to make full use of these plateau livestock manure.Therefore,this thesis closely focuses on the high value-added functional utilization and resource application of plateau livestock manure（Yak dung,Tibetan pig manure）,and develops efficient and economical adsorbents and electrode materials.Mainly carry out the following work:（1）When preparing plateau livestock manure biochar as uranium adsorption material,we provide a method for manure treatment and solve the problem of uranium wastewater.The biochar of plateau livestock manure（Yak dung,Tibetan pig manure）is mainly prepared by low-temperature carbonization.The effects of different p H values,different amounts of biochar,reaction time and temperature on uranium wastewater are investigated,and the mechanism research is clarified.At p H 4,temperature 70℃and adsorption time 210 min,Yak dung biochar Y-500 has the best removal effect on uranium.In the adsorption kinetics,the quasi-secondary kinetic model can better describe the adsorption kinetics process of biochar from plateau livestock manure（Yak dung,Tibetan pig manure）,which are mainly chemical adsorption,and the equilibrium time is at the three temperatures.The order is Y-700<Y-300<Y-500.In the adsorption isotherm,compared with Tibetan pig manure biochar,Yak dung biochar is more in line with the Langmuir model,and the order of the maximum adsorption capacity is Y-700<Y-300<Y-500.In general,of the two types of biochar,the maximum adsorption capacity（119.2mg/g）of Yak dung biochar（Y-500）is higher than the adsorption capacity of Tibetan pig manure for uranium（106.87mg/g）,and the equilibrium adsorption time the shortest.（2）In the preparation of biochar capacitors for plateau livestock manure,we demonstrated a method of turning waste into treasure,which solved the problem of energy conversion and storage.Mainly through KOH activation method using plateau livestock manure as raw material,without adding any chemical substances,successfully prepared nitrogen-doped porous carbon,to achieve waste recycling.The results showed that plateau livestock biochar（Yak dung,Tibetan pig manure）prepared under different high-temperature carbonization activation conditions,the specific surface area of??Yak dung activated carbon increased from 508.9 m²g^-1to 635.2 m²g^-1,the ratio of Tibetan pig manure activated carbon The surface area is increased from 255.9 m²g^-1to 228.9 m²g^-1.The specific surface area of??Yak dung biochar is 2 times higher than that of Tibetan pig manure biochar.It is a typical micro-mesoporous material.As Tibetan pig manure biochar contains a large amount of Si O₂and Ca O,it will directly affect the conductivity of the electrode.Contrary to Tibetan pig manure biochar,Yak dung biochar has better electrochemical performance.At a current density of 1A g^-1,the specific capacitance of N-YD-800 is 346.3 F g^-1higher than that of N-PD-800 of 39.46 F g^-1.After 5,000 charge-discharge cycles of N-YD-800,the specific volume ratio of the material remains at 93.3%.Therefore,it is hopeful that nitrogen-doped yak dung-based carbon can be applied to electrode materials for supercapacitor applications,so as to solve the problems of animal manure resource treatment and electrode material preparation costs.In summary,plateau livestock manure（Yak dung,Tibetan pig manure）biochar has adsorption properties and electrochemical properties.Further analysis of the structure and function of the digestive system of yak and Tibetan pig,yak and Tibetan pig are mainly different from the foregastric,and the unique physiological functions of microorganisms.Monogastric digestion has digestive enzymes,hydrochloric acid and mucus for digestion.In addition,compound stomach animals also have anaerobic fungi,bacteria,and ciliates.Therefore,the rumen-fermented Yak dung has better performance than Tibetan pig manure.The raw materials and methods for finding high-quality carbon materials are obtained,and the high value-added functional utilization and resource application are realized.