蔬菜废弃物厌氧发酵制沼气的工艺条件研究

文章以蔬菜废弃物作为发酵原料,以长期驯化的猪粪和池塘污泥作为接种物,将发酵料液的总固体(TS)含量分别设置为8%,10%和12%,置于室温和中温(35℃)条件下进行厌氧发酵实验,通过监测发酵过程中的pH值、日产气量和CH_4含量的变化,研究蔬菜废弃物在不同条件下的厌氧发酵产气特性。研究结果表明:中温条件下,以池塘污泥作为接种物时,发酵料液TS含量为12%的实验组的日产气量峰值和原料产气率分别为1 750 mL和367.69 mL/g,产气效果优于其它实验组;在中温条件下,以池塘污泥作为接种物时,发酵料液TS含量为10%的实验组在稳定期的CH_4平均含量为80.55%,高于其它实验组。     

大中型猪粪厌氧发酵沼气工程的管理技术

一、前言近七八年来,随着农村经济体制改革的深入,养猪业的集约化生产日趋发展。尤其是大中城市附近的郊县,结合菜篮子工程兴办了一批大中型鸡场和猪场,从而出现了大量禽畜粪便堆积,造成严重的环境污染。应用厌氧消化工艺建造大中型沼气集中供气工程,既能使粪便的污染得到控制,保护了生     

木质纤维类农林加工废弃物厌氧发酵产甲烷潜力研究

为评估木质纤维类农林加工废弃物直接作为沼气发酵原料的可行性,采用批次试验,选取其中产量大、分布广的甘蔗渣、棉籽壳、花生壳和木屑4种原料,在中温(37℃)条件下进行厌氧发酵产甲烷潜力(BMP)试验。结果表明:甘蔗渣、棉籽壳、花生壳及木屑4种农林加工废弃物的VS累积甲烷产量(m L/g)分别为205.67,180.30,35.09及4.52,产气高峰期主要集中在厌氧发酵的前26 d;供试原料的产甲烷潜力与其半纤维素、纤维素含量均呈极显著正相关(P<0.01),与木质素含量呈显著负相关(P<0.05)。木质素的存在显著降低了木质纤维类农林加工废弃物的产甲烷潜力。甘蔗渣、棉籽壳具有较高的产甲烷潜力,可直接作为沼气发酵原料;而花生壳、木屑则需进行有效的预处理才可应用到沼气发酵中。     

一种处理鸡粪的小型高效厌氧发酵装置

介绍一种适于养鸡专业户使用的小型高效厌氧发酵装置,可以连续处理每天产生的鸡粪,产气率较高.使用该装置,可获得较高的经济、环境效益.     

几种轻工业加工废弃物厌氧发酵制取生物燃气潜力研究

本试验以典型的轻工业有机废弃物为原料,采用中温批式发酵工艺进行了厌氧发酵制取生物燃气的研究。结果表明,木薯淀粉渣、木薯杆、糖蜜酒精废水、肉食加工废水及果汁废水的产气率分别为623.7 mL/gVS、208 mL/gVS、223.0 mL/gCOD、335.4 mL/gCOD和383.4 mL/gCOD,产甲烷率分别为355.1 mL/gVS、120.6 mL/gVS、94.7 mL/gCOD、187.2 mL/gCOD和136.1 mL/gCOD,平均甲烷含量分别为56.9%、58.0%、43.0%、55.8%和35.5%。这些典型的轻工业加工废弃物皆为生物燃气发酵的适用原料,但是有各自的发酵产气特点,可根据不同原料采用不同的预处理方法及发酵工艺,以期取得更好的产气效果。     

构树与不同生物质废弃物混合厌氧发酵产气性能研究

在温度(55±1℃)和总挥发性固体浓度(2%)为固定参数,碳氮比(C/N)为可变参数的条件下,研究了构树和牛粪、餐厨垃圾、水稻秸秆分别进行混合发酵的产气性能。研究结果表明:与单一发酵相比,混合发酵均能提高甲烷产量,当构树与餐厨垃圾混合物的C/N为20时,可获得最高的累积产甲烷量(411.71 mL/g),比构树和餐厨垃圾单独发酵时的累积产甲烷量分别提高了45.45%和12.61%;构树与餐厨垃圾、牛粪、水稻秸秆进行混合发酵时,原料之间均存在协同作用,其中,构树与水稻秸秆在C/N为15的条件下进行混合发酵时,协同指数最高,为18.69%;构树与不同废弃物的混合厌氧发酵过程符合修正Gompertz方程(R~20.97),可用该拟合方程模拟混合厌氧发酵过程。     

皇竹草厌氧发酵特性及稀土元素溶出研究

为探讨稀土尾矿区修复用皇竹草的厌氧发酵特性和发酵过程稀土元素溶出情况,开展不同发酵浓度（总固体浓度分别为2%、4%、6%、8%、10%）的中温（37±1℃）批式厌氧发酵实验。结果表明,总固体（TS）浓度为4%条件下皇竹草产甲烷性能最佳,日产甲烷率和累积产甲烷率分别为25.56mL/g和197.33m L/g。采用修正Gompertz方程能较好地模拟不同TS下皇竹草发酵累积产甲烷率的变化。分析发酵液中稀土元素浓度变化,结果表明,皇竹草内的稀土元素在厌氧发酵过程中只发生小部分溶出,主要包括La、Ce、Nd、Sc、Y等,各处理发酵液中稀土元素浓度并未超出文献报道的抑制浓度。相关性分析结果表明,稀土元素溶出率与发酵体系的TS浓度、化学需氧量（COD）呈负相关,与pH呈正相关。研究可为稀土矿区皇竹草沼气工程应用和发酵剩余物的肥料化利用提供指导。     

浙江省农业废弃物的能源利用初探

讨论了浙江省2004年农业废弃物秸秆和畜禽粪便的资源量及利用现状，论述了秸秆压缩成型、秸秆气化、液化及畜禽粪便的沼气、沼液、沼渣等资源化综合利用的途径。     

干式厌氧发酵技术现状与国内应用项目简介

针对当前农业、工业及城市排放中的大量高浓度有机固体废弃物须要进行无害化处理和资源化利用的问题,文章从生物无害化处理的角度对当前的应用技术进行了探讨.从厌氧消化项目示范角度分析了国内外干式厌氧发酵技术工艺研究现状,并结合当前干法发酵工艺及反应器开发的进展,列举了在国内稳定运行的3个干式发酵案例,对各发酵工艺的优缺点进行了...     

Dry anaerobic fermentation of agricultural residues

The dry anaerobic fermentation plays an important role in the field of bioengineering, especially in the production of energy (biogas) and organic fertilizer. Meanwhile the pollution effect of the solid wastes are decreased. Dry anaerobic fermentations of different organic solid wastes were studied. These included cotton stalks, treated cotton stalks, corn stalks, rice straw, and water hyacinth. The effect of the initial solid concentration, temperature, starter, and buffer additives on dry anaerobic fermentation on biogas production rate and yield has been studied.     

我国城市生活垃圾厌氧消化处理的探讨

分析了我国城市生活垃圾处理现状及存在问题，探讨了以厌氧消化技术为主的城市生活垃圾处理方式，为解决我国的城市生活垃圾问题提供参考。     

厌氧干发酵技术研究进展

厌氧干发酵技术正逐渐成为世界各国处理有机同体废弃物以及生产新能源的重要选择.文章综述了厌氧干发酵机制以及厌氧干发酵工艺在发酵底物的选取、预处理、接种、发酵过程管理等方面的研究进展,总结了该技术在基础研究和实际应用中存在的一些问题,展望了其发展前景.     

Effects of size and autoclavation of fruit and vegetable wastes on biohydrogen production by dark dry anaerobic fermentation under mesophilic condition

Fermentative hydrogen production from fruit and vegetable wastes (FVWs) through Dry Fermentation Technology (DFT) was studied through three independent experiments in order to find out the effect of particle size and autoclaving pretreatment on bio-hydrogen production from FVWs and as follows: (1) autoclaved FVWs with sizes < 5 cm (experiment I); (2) raw FVWs with sizes < 5 cm (experiment II) and (3) autoclaved FVWs with sizes > 5 cm (experiment III). The assay with autoclaved waste yielded a higher percentage of hydrogen in the headspace of the dry fermenter reaching a maximum value of 44% in experiment I. However, the maximum hydrogen production was obtained in experiment III with 14573 NmL at a yield of 23.53 NmL H₂/gVS. Profiling of the microbial communities by denaturing gradient gel electrophoresis (DGGE) indicated that the most prominent species were the genera Clostridium, Bifidobacterium, and Lactobacillus.     

城市有机垃圾车库式干发酵技术

城市有机垃圾处理和资源再生利用已成为我国建设资源节约型和环境友好型社会中迫切需要解决的问题。欧洲国家中以德国为代表的车库式干发酵技术(Garage-type dry anaerobic digestion)已经成熟,可进行规模化的沼气生产。文章着重介绍了车库式干发酵沼气工程的技术要点,并以德国Loock TNS工艺和黑龙江宾县车库式干发酵项目为例,介绍了有机垃圾车库式干发酵喷淋回流、系统密封等关键技术,以期为我国车库式干发酵工程的工艺设计提供参考。     

鸡粪和玉米秸秆混合干发酵特性及微生物多样性研究

鸡粪中添加一定量的秸秆可以有效解决单一物料发酵出现的C/N失衡问题。为了维持系统稳定,文章以鸡粪为底物添加10%的玉米秸秆开展中温连续式干发酵实验,研究发酵消化系统的理化参数、产气特性、酶活性以及微生物群落的变化情况。研究结果表明:甲烷最高日产量为43.39 L;在整个厌氧消化过程中,氨氮浓度未对微生物的生长产生抑制作用;消化液的pH值呈现出先稳定后减小,最后上升至7±0.2并保持稳定的变化趋势,VFAs浓度的变化趋势为先上升后趋于稳定;COD浓度最大值为110 400 mg/L,纤维素酶、半纤维素酶、蛋白酶、脂肪酶和淀粉酶活性的最大值分别为2.44×10⁵,0.34,153.06,471.93,307.76 IU/L;在水解酸化阶段,门水平上的优势菌为广古菌门、厚壁菌门、变形菌门和拟杆菌门,产甲烷阶段的优势菌属主要为甲烷丝状菌属、甲烷拟杆菌属和甲烷球形菌属。     

Biohydrogen production from soluble condensed molasses fermentation using anaerobic fermentation

Using anaerobic micro-organisms to convert organic waste to produce hydrogen gas gives the benefits of energy recovery and environmental protection. The objective of this study was to develop a biohydrogen production technology from food wastewater focusing on hydrogen production efficiency and micro-flora community at different hydraulic retention times. Soluble condensed molasses fermentation (CMS) was used as the substrate because it is sacchariferous and ideal for hydrogen production. CMS contains nutrient components that are necessary for bacterial growth: microbial protein, amino acids, organic acids, vitamins and coenzymes. The seed sludge was obtained from the waste activated sludge from a municipal sewage treatment plant in Central Taiwan. This seed sludge was rich in Clostridium sp.A CSTR (continuously stirred tank reactor) lab-scale hydrogen fermentor (working volume, 4.0 L) was operated at a hydraulic retention time (HRT) of 3–24 h with an influent CMS concentration of 40 g COD/L. The results showed that the peak hydrogen production rate of 390 mmol H₂/L-d occurred at an organic loading rate (OLR) of 320 g COD/L-d at a HRT of 3 h. The peak hydrogen yield was obtained at an OLR of 80 g COD/L-d at a HRT of 12 h. At HRT 8 h, all hydrogenase mRNA detected were from Clostridium acetobutylicum-like and Clostridium pasteurianum-like hydrogen-producing bacteria by RT-PCR analysis. RNA based hydrogenase gene and 16S rRNA gene analysis suggests that Clostridium exists in the fermentative hydrogen-producing system and might be the dominant hydrogen-producing bacteria at tested HRTs (except 3 h). The hydrogen production feedstock from CMS is lower than that of sucrose and starch because CMS is a waste and has zero cost, requiring no added nutrients. Therefore, producing hydrogen from food wastewater is a more commercially feasible bioprocess.     

A sequential process of anaerobic solid-state fermentation followed by dark fermentation for bio-hydrogen production from Chlorella sp.

Microalgal biomass has recently been one of the most widely studied feedstocks for bio-hydrogen production, owing to its richness in fermentable components, e.g. polysaccharides and proteins, and high biomass productivity. In this study, biomass of microalga Chlorella sp. TISTR 8411 was converted to hydrogen through a sequential process consisting of an anaerobic solid-state fermentation (ASSF) followed by a dark fermentation. The microalga was grown photoautothrophically in 80-L rectangular glass tanks and then scaled-up to a 240-L open pond for the production of biomass. The highest biomass concentration attained was 4.45 g L⁻¹. The biomass was harvested with over 90% flocculation efficiency at pH 11.5 and a biomass concentration of 2.6 g/L. The sequential process gave a total hydrogen yield (HY) of 16.2 mL/g-volatile-solid (VS), of which 11.6 mL/g-VS was from ASSF. The high HY obtained from the ASSF indicated that it was effective and could be integrated with a conventional hydrogen production process to improve energy recovery from biomass.     

醋糟厌氧发酵特性的研究

以醋糟为厌氧发酵原料,分别进行了连续进料试验和全进全出料试验。连续进料试验结果表明,在每天进料量保持不变的情况下,日产气量稳定,平均产气率为0.918 m3/(m3.d),最高产气率可达1.111 m3/(m3.d)。经过计算可知,8.52 kg醋糟可产1 m3沼气。全进全出料发酵试验结果表明,醋糟厌氧发酵的体积上浮和膨胀非常明显。当进料浓度为4%时,料液最大膨胀体积为322.68 cm3,为发酵料液体积的28.8%。醋糟厌氧发酵具有降解速率快,滞留期短等特点。