牛粪与超声预处理污泥中温混合厌氧消化效果

Mixed Anaerobic Digestion of Cattle Manure and Ultrasonic Pretreated Sludge

文章以牛粪和超声预处理污泥为发酵原料,在恒温35℃±1℃及底物浓度为15 gVS·L^(-1)的条件下,采用正常运行的大型沼气池沼液作为接种物,研究不同配比(VS_(污泥)∶VS_(牛粪)分别为1∶0,2∶1,1∶1,1∶2,0∶1)对混合厌氧消化效果的影响。研究表明,在35℃±1℃条件下,超声预处理污泥与牛粪的比例为1∶2时累积产气量高于其他4种比例,VS产气率达到了470.33 mL·g^(-1),甲烷产量在发酵稳定后达到了58.68%。发酵过程中pH值,NH_4^+-N,COD的变化表明了混合厌氧消化能够平衡营养物质,稀释有毒物质,具有协同作用,发酵过程中未出现酸抑制以及氨抑制。进一步研究得出,将超声预处理污泥与牛粪按一定比例混合发酵可以将产气高峰提前,并出现"双峰",提升产气速率,大幅提升了原料的产气潜力。

Cattle manure mixed with ultrasonic pretreated sludge as raw material, anaerobic digestion were carried out under condition of temperature 35℃＋1℃, VS concentration 15 g ·L-1 , and different sludge and cattle manure mixing ratio （ sludge VS： cattle manure VS = 1： 0, 2：1,1： 1,1 ： 2,0： 1 ） , adopting biogas slurry from a normal operated large scale biogas digester as inoculums. The results showed that the mixing ratio of 1：2 obtained the highest gas production, for which the VS gas production rate reached 470.33 mL ·g-1 , and the methane content was 58.68%. Through the determination of pH, NH4＋ -N, COD, it was showed that the mixed anaerobic digestion could balance the nutrients, dilute toxic substances, and had a synergistic effect with no acid suppression and ammonia inhibition during the digestion process. Further study proved that ultrasonic sludge mixed with cattle manure could advance the gas production peak and appear double peaks, improving the gas production potential of raw material.