生物炭加速餐厨垃圾厌氧消化的机理

为考察生物炭对餐厨垃圾厌氧消化的影响并探究其影响机理，采用批次实验，以餐厨垃圾为基质，设置污泥空白组、餐厨垃圾对照组和生物炭实验组。检测系统的甲烷日产量、甲烷浓度、渗滤液pH、电导率、挥发性脂肪酸（乙酸、丙酸和丁酸）和氨氮浓度，并对生物炭进行了表征（pH、表面元素、表面形态和官能团）。结果表明，生物炭的添加使体系的最大日甲烷产量提高24.09%，并保持较高的pH，乙酸、丙酸、丁酸峰值分别降低了10.46%、9.96%和13.79%。生物炭丰富的孔结构为微生物提供了生长位点；生物炭的表面金属元素（K、Ca、Mg）和官能团（—OH、C≡C、—NH、C＝O（C—O）、 CO 3 2 - ）使其具有较高的碱度，从而提高厌氧消化系统的缓冲能力和产甲烷菌活性，进而提高产甲烷速率。

Mechanisms for enhancement of biogas generation from food waste anaerobic digestion with biochar supplement

A series of batch experiments were carried out to investigate the effects of sawdust biochar on food waste (FW) anaerobic digestion (AD), including a blank group of sludge, a control group of FW and a test group of FW with biochar. Different parameters were analyzed to evaluate the change of biogas and leachate characteristics during the AD process, including daily methane yield, methane content, pH, conductivity, volatile fatty acids and ammonia nitrogen etc. The results revealed that with the addition of biochar, the maximum daily methane yield increased by 24.09% with a high pH of the AD system, and the peak values of acetate, propionate and butyrate decreased by 10.46%, 9.96% and 13.79%, respectively. In addition, the biochar was characterized with pH, surface morphology, surface elements and functional groups. It can be seen that the rich porous structure could provide growth sites for microbes, the surface elements (K, Ca, Mg) and functional groups (—OH,C≡C,—NH,C＝O (C—O), CO 3 2 - ) on the biochar led to the increase of its alkalinity, thus enhanced the buffer capacity and methanogens activity as well as methane production rate in AD.