Passivation Effect Of Biochar And Wood Vinegar On Heavy Metals In Livestock And Poultry Breeding Wastewater

In recent years,China's livestock and poultry industry has developed rapidly,but the pollutant production and discharge from livestock and poultry industries become more and more serious.In the actual production process,some hevy metals such as copper and zinc are commonly added in the feed in order to prevent the occurrence of diseases and promote the growth.However,due to the lack of effective treatment and comprehensive utilization of livestock and poultry manure,large amounts of the livestock and poultry manure pollutants are discharged into the environment,become a major source of soil,water and air pollution,among which the heavy metals can jeopardize human health through the food chain.Current methods of heavy metal removel in livestock and poultry discharge including compost method,passivation,drain immersion method and chemical method,with many researches focus on the ulitization of biochar as adsorbents to reduce the bioavailability of heavy metals in livestock and poultry wastewater,but report of joint use of biochar and wood vinegar as to deal with the heavy metal problem of livestock and poultry wastewater is rare.Given that wood vinegar liquid is a rich agricultural biomass resource,the combined use of wood vinegar liquid and biochar to treat heavy metals in livestock and poultry wastewater not only can realize efficiency utilization of agriculture and forestry residues,but also can solve the pollution problems of livestock and poultry wastewater,which has vital significance in the ecology,resources and agricultural sustainable development.This study was conducted to study the effects of wood vinegar and biochar on the passivation of heavy metals in swine wastewater.Inductively coupled plasma mass spectrometry(ICP-MS)was used as the main analytical means to analyze heavy metals in pig wastewater,biological charcoal and wood vinegar.According to the characteristics of heavy metal content in pig wastewater,the design of gradient concentration of wood vinegar and biological carbon in different treatment conditions to carry out its biological characteristics in the culture wastewater.Effect of DTPA extraction on heavy metal concentration.Finally,through the data mining of the determination of heavy metal content,the passivation effect of wood vinegar and biological carbon on heavy metals in aquaculture wastewater is explored.The purpose is to provide a reliable theoretical basis for the control technology of heavy metals in livestock and poultry wastewater,and to provide a technical hand for the research on the use of biological carbon and wood vinegar in green agriculture and ecological agriculture.The results showed that there was no obvious linear relationship between heavy metal content in rice straw biological carbon and pyrolysis temperature at 300?-500?,the content of heavy metals was the lowest at 500? and the content of heavy metals was the highest under the condition of 400?.Under the condition of 300?-700?,most of the weight of maize straw biomass increased with the temperature of cracking.The content of metal elements has a downward trend.The total change trend of four elements in Mn,Ba,Zn,Mo and As is as follows: with the increase of the content of biological carbon,the concentration of effective heavy metals is increasing,the elements of Co are decreasing;Fe,Cu and Se three elements are in the waste water under the dynamic treatment conditions.In the static condition,the content of the effective state elements showed an upward trend,which showed that the three elements were greatly influenced by the content of the biological carbon under the dynamic conditions.The experiment of heavy metals in the passivated pig wastewater from the wood vinegar solution showed that the wood vinegar of 0.5%-2.0% could obviously reduce the content of the effective heavy metals in the wastewater,and 5% of the wood vinegar.In liquid treatment,the efficiency of passivation decreased.In the actual production process,we should start the experiment with the amount of 0.5% wood vinegar added,in order to make the concentration of heavy metals in the water reach the standard of the organic manure emission standard,take into consideration the economy and applicability of the production,and finally determine the best technology of adding wood vinegar to the research and development of heavy metal passivation technology,biological charcoal and wood vinegar in the waste water of livestock and poultry.It can provide references for the promotion of liquid properties and the large-scale application of organic fertilizers.