Influence Of Attapulgite On Leachability Of Heavy Metals During Composting Of Chicken Manure

Livestock manure is one of the problems has been difficult to deal with at home and abroad, after the full use of this part of the resources can bring great economic benefits. Thermophilic aerobic composting is processed poultry manure research trends, the use of high-temperature fermentation partial degradation of livestock excrement class of persistent organic pollutants, kill livestock manure pathogens, passivation livestock excrement class of heavy metals, reduce heavy metals The migration rate of conversion, so that as little as possible of heavy metals into the food chain, to reduce damage to human health.Test manure collected from Ganzhou District of Zhangye City in Gansu Province, Linze County, Gansu Province, attapulgite clay thermophilic aerobic composting for inactivation agent. Add different proportions of attapulgite to high temperature fermentation in livestock manure compost, compost attapulgite explore the fermentation process of immobilization, the water, EDTA, DTPA and hydrochloric Four Forest filtrate extraction of heavy metals in the process of composting, explore changes in the concentration and Heavy Metals concentrations of heavy metals, analytical relevance of heavy metal concentration differences between different times and different treatments and the effective state and Heavy Metals and Heavy Metals by multiple comparisons between and analysis of variance.The results showed that:(1) During the experiment, the initial temperature of the experiment appear in the ups and downs of the phenomenon, namely the initial test temperature in 5 days to 50 ℃, the maximum temperature is about composting process may be pre-added to ferment the reason, but then the temperature is gradually lowered, occasional temperature phenomenon. The reason may be the pile is too small and too large temperature difference between day and night temperatures occasionally rise, with chicken, attapulgite, straw mixing uniformity related.(2) Leaching during composting varying concentrations of heavy metals showed different trends,different states leaching of heavy metals in the composting process are presented Cr clear upward trend, concentration compost maturity compost or more after the initial concentration of 2 times. Different leaching heavy metals and Cu in the initial concentration of compost compost maturity relatively minor downward trend. Different leaching heavy metals Ni and Zn in concentration after compost maturity remained unchanged or decreased small amplitude.(3) Leaching of heavy metals in varying concentrations compost pre large, small changes in the concentration of heavy metals in the latter part of that change in the concentration of heavy metals leaching basically completed in the early compost. Leaching of heavy metals concentrations in different proportions among attapulgite added processing A3, A6, A9 significant difference between in dealing with A9, A12, A15 difference was not significant between that composting manure attapulgite added content exceeds 25% attapulgite add conversion leaching heavy metals not significantly reduced role. Add chicken manure composting process attapulgite have to reduce leaching heavy metals can promote.(4) Between the different parts of extracting agent to extract heavy metals relevance P>0.05, while hydrochloric acid extractable heavy metals and EDTA-extractable Cr relevance P<0.05, that is leaching heavy metals in attapulgite Add chicken manure composting process between there is no correlation necessarily reliable.(5) Leaching of heavy metals and heavy metal residue state there is a certain negative correlation, shower corresponding reduction in filter state when that is the concentration of heavy metals will increase in residual heavy. Leaching of heavy metals and heavy metals in acid-soluble state, oxidation state, reducing state association is not uniform, without some heavy metals leaching of heavy metals and chemical forms of the existence or relevance of certain forms of heavy metals and other chemicals.