There were approximately 20 billion chickens in the world in 2010, with 23% of the chicken population found in China. In 2009, the rapid development of chicken farms in China resulted in the production of 126 million tons of poultry manure. If managed inappropriately, poultry manure can cause serious environmental problems by polluting water, air, and soil. Anaerobic digestion is a complex bioconversion process that can treat organic waste and generate biogas with a high methane content that can be used as renewable energy, hence reducing the consumption of fossil fuel and curtailing greenhouse gas emissions. Ca2+-betonite is an environmental friendly material and is widely used in compost, heavy metal removal, pollutant adsorption, etc. In order to investigate the effect of betonite addition on anaerobic digestion of poultry manure, an orthogonal experiment L8(23)was conducted to determine amount of poultry manure (organic loading rate (OLR)), amount of bentonite and inoculum concentration on characteristics of methane production and organic acid production during anaerobic batch digestion of poultry manure under mesophilic condition (35±1)℃. The results showed that bentonite addition could significantly increase methane production per VS by 22.72% and 27.72% with 3.0% and 1.5% betonite addition (based on poultry manure total solids), respectively compared to the control group under low OLR condition. Methane production from poultry manure with 3.0% or 1.5% betonite addition had no significant (P>0.05) difference under low OLR condition. Specifically, methane production could be very significantly (P<0.05) increased by adding betonite under high OLR condition. Methane production was increased by 78.68% and 55.41% with 3.0% and 1.5% betonite addition, respectively, compared to the control group under high OLR condition. Methane production from poultry manure with 3.0% or 1.5% betonite addition had significant (P<0.05) difference under high OLR condition. In the treatment with 19.91 g VS (volatile solid) poultry manure, 3.0% bentonite addition and 20% inoculum concentration, the highest methane production was observed with methane production 301.92 mL/g, very significantly higher (P<0.05) than control group (87.8% more) and its variable cost was also the lowest with 2.43 Yuan per m3 methane among all treatments. Variable costs of methane production from anaerobic digestion of poultry manure with betonite were 0.40 to 1.68 Yuan per m3 lower than from anaerobic digestion of poultry manure only. Peak values of dissolved organic carbon (DOC) appeared five days earlier and were lower than the control group under low OLR condition. Variance of DOC, pH value and dissolved inorganic carbon (DIC) in control group was higher than treatment groups with betonite showed stability of poultry manure anaerobic digestion could be improved by bentonite addition through increasing consistent of DOC degradation. Interestingly, formic acid and propionic acid were not found during the whole anaerobic digestion process of poultry manure with betonite. Variance of acetate, lactate and n-butyrate of treatment groups with betonite were lower than the control group showing that betonite addition could enhance the stability of anaerobic digestion process of poultry manure. Organic loading rate was the key factor of anaerobic digestion of poultry manure with bentonite under low OLR condition. Amount of betonite was the key factor of poultry manure anaerobic digestion with bentonite under high OLR condition. Inoculum concentration and OLR had significant interaction on acetate concentration. Organic loading rate had significant effect on lactate concentration. No interactions of these three factors were found on lactate concentration.%为探究膨润土对鸡粪厌氧消化过程中产甲烷特性和可溶性有机酸代谢特性的影响，采用L8（23）正交试验设计，以鸡粪添加量（有机负荷率）、膨润土添加量和接种量为三因素，每个因素设置2个水平，研究了中温条件下(35±1)℃膨润土添加对鸡粪厌氧消化过程中产酸和产甲烷特性的影响。结果表明：与对照组相比，低有机负荷条件下，膨润土添加能显著（P＜0.05）提高鸡粪挥发性固体（volatile solid，VS）产甲烷量，添加量为3.0%和1.5%时VS产甲烷量分别提升了22.72%、27.72%（膨润土添加量不同的组差异不显著（P＞0.05））；高有机负荷条件下，膨润土添加能极显著（P<0.01）提高鸡粪VS产甲烷量，添加量为3.0%和1.5%时VS产甲烷量分别提升了78.68%和55.41%（膨润土添加量不同的组差异显著（P＜0.05））。当鸡粪添加量为19.91 g挥发性固体，膨润土添加量为3.0%（占干基比）和接种量为80 mL（体积分数20%）时，单位挥发性固体产甲烷量最高为301.92 mL/g，比对照组高87.8%，此时可变成本也最低为2.43元/m3，比两对照组分别低1.29和1.68元/m3。方差分析表明：膨润土添加可提高鸡粪厌氧消化过程中挥发性脂肪酸，pH值，可溶性有机碳和可溶性无机碳的稳定性。膨润土可加强鸡粪厌氧消化系统的稳定性，降低产甲烷的可变成本，为膨润土强化鸡粪厌氧处理提供了试验验证据。
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