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1.
奶牛粪便与秸秆混合发酵过程通风工艺优化   总被引:2,自引:2,他引:0  
通风是影响好氧发酵的重要技术参数,但目前对于奶牛粪便好氧发酵通风缺乏系统研究,导致发酵后物料质量参差不齐,为优化奶牛粪便好氧发酵过程中的通风参数,该研究采用响应曲面法,以通风速率、通停比、通风时间为3因素,通过中心组合试验设计方法(Box-Behnken Design)设计17组试验,以含水率和病原菌去除效率为响应值,...  相似文献   

2.
对城市污泥和稻草秸秆混合物料进行好氧堆肥试验,研究不同通风量堆肥过程氧气浓度的变化特征和差异性,分析了耗氧速率与温度和含水率之间的相关性。结果表明:(1)温度的变化经历4个时期:升温期、高温期、降温期和稳定期,最高温度达到74.20℃;含水率先升高,后降低,然后趋于稳定;(2)不同时期氧气浓度逐渐下降,高温期下降最明显;(3)氧气浓度在高温期与稳定期之间差异性达到极显著水平(P0.01);(4)各处理耗氧速率最大值的大小顺序为:3号箱2号箱1号箱4号箱,耗氧速率下降为0.11%/min,可以作为堆肥的腐熟评价指标,3号箱耗氧速率和温度与含水率的相关性达到极显著水平(P0.01)。当通风量为1.00 m~3/h时,堆肥历时共16 d,高温期最长(6 d),氧气浓度超过17%,耗氧速率最大(0.75%/min),最适合污泥好氧堆肥发酵。  相似文献   

3.
旨在对农村有机生活垃圾厌氧发酵产沼气的潜力进行研究。对江苏省徐州市沛县大屯街道王庄村生活垃圾分类处置中心每月一次采集样品,并对一周年十二个月份的生活垃圾样品进行批式中温厌氧发酵产气潜力研究,考察农村生活垃圾作为发酵原料周年沼气产量和甲烷产量的变化,各月份试验组的累积沼气产气量范围为447~1 398 mL、累积甲烷产气量范围为215~865 mL。并用SPSS数据分析发现农村生活垃圾含水率、TP、TK、TN、有机质、C/N、半纤维素、纤维素、木质素的含量均对产沼气潜力有影响,其中纤维素含量会对产沼气潜力有显著的正向影响关系,而TP会对产气潜力产生显著的负向影响关系,最后,该研究根据生活垃圾理化性质数据基础上建立了多元线性逐步回归最优方程,可根据农村有机生活垃圾的含水率、纤维素和木质素的含量预测其厌氧发酵产沼气潜力。  相似文献   

4.
为解决厨余垃圾等有机废弃物处理难的问题,该研究以厨余垃圾、绿化废弃物和茶叶渣为主要原料,通过控制通风方式和菌种类型在堆肥成套设备内开展中试好氧堆肥,选取温度、含水率、碳氮比(C/N)、总养分、有机质含量、种子发芽指数和卫生学特性等指标评估共堆肥系统的技术可行性和经济可行性。结果表明:选择间歇式通风方式并按质量分数1‰投加复配菌剂,堆肥在65 ℃以上高温持续7 d;经10 d发酵,物料含水率和C/N分别从63.5%和31.5降至30.1%和9.6;堆肥产物的总养分(9.8%,质量分数,下同)和有机质含量(43%)均远高于NY/T 525-2021农业行业标准(总养分≥4%,有机质含量≥30%);堆肥产物腐熟度和卫生学特性状况良好,种子发芽指数达88.3%,粪大肠菌群数<3 个/g,产物中未发现蛔虫卵。该共堆肥系统的废物平均处置成本低至(248.67±19.89)元/t。研究结果可为实现厨余垃圾、绿化废弃物和茶叶渣的低成本、规模化处理,有效解决厨余等有机废弃物环境污染问题提供参考依据。  相似文献   

5.
猪粪堆肥挥发性有机物的产生规律与影响因素   总被引:5,自引:3,他引:2  
堆肥是畜禽粪便处理及资源化利用的有效途径,然而堆肥过程中极易产生挥发性有机物(VOCs,volatile organic compounds),引发恶臭问题,并对人体健康带来危害。该研究以猪粪和秸秆为原料,通过堆肥试验,研究了含水率、碳氮比和通风速率等工艺参数对猪粪堆肥过程中主要VOCs产生的影响。研究结果表明:堆肥过程中TVOCs的最高体积分数可达2 000×10~(-6)以上,主要在堆肥升温期产生。二甲二硫、二甲三硫是主要的致臭VOCs,其中,影响二甲二硫排放的主要因素为物料初始含水率,影响二甲三硫排放的主要因素为通风速率。极差及方差分析结果表明,堆肥过程中采用含水率65%,碳氮比30,通风速率0.1 m~3/(min·m~3)可以有效控制VOCs的排放。  相似文献   

6.
养殖业的发展造成了周边环境的严重污染。好氧堆肥技术是处理固体有机废弃物的一种有效方法。该文利用自制发酵箱进行了牛粪与不同调理剂一玉米芯、玉米秸秆和稻草的混合好氧堆肥试验。试验结果表明,当堆肥底料的初始碳氮比为27:1,初始含水率为65%时,玉米芯、玉米秸杆和稻草均可作为调理剂与牛粪进行好氧堆肥,且可达到无害化要求。而采用粒径大、多孔、疏松的玉米芯作为调理剂,有利于通风供氧,堆体升温和降温均较快,高温持续时间长,堆料腐熟快,有利于加快堆肥的进程。  相似文献   

7.
病死猪辅热快速好氧发酵工艺参数优化与装备研制   总被引:1,自引:1,他引:1  
将病死猪、辅料拌合后加入发酵菌种,在50~70℃条件下进行辅热快速好氧发酵处理,可在短时间内将病死猪转化为干颗粒物料。为了优化发酵工艺参数,提高发酵处理质量,该文采用辅热快速好氧发酵试验装置,以猪死胎为原料、麸皮为辅料,选取通风量和温度为试验因素,以产物的总游离氨基酸(free amino acid,FAA)质量分数、含水率、粒度分布和pH值作为试验指标,开展了病死猪辅热快速好氧发酵处理试验。发酵温度选取50、60和70℃3个水平,通风量选取8、9和10 L/(L·min) 3个水平。结果表明,发酵温度60℃、通风量10 L/(L·min)时处理效果最佳。在此基础上,设计并试制了一台处理能力为150kg/批的病死猪辅热快速好氧发酵处理设备,并进行了初步试验。设定通风量为10 L/(L·min),发酵温度为60℃,发酵3d后物料中的FAA质量分数为20.74g/kg,含水率为14%左右,pH值为5.4,88.89%能通过4.75 mm编织筛,未检出大肠杆菌,平均每处理1 kg病死猪的能耗为2.37 kW?h。试验结果表明,试制的装备能在3 d内将冰冻状态的病死猪无害化处理转变为干颗粒物料,处理产物能满足后续有机肥生产的要求。  相似文献   

8.
养殖业的发展造成了周边环境的严重污染。好氧堆肥技术是处理固体有机废弃物的一种有效方法。该文利用自制发酵箱进行了牛粪与不同调理剂-玉米芯、玉米秸秆和稻草的混合好氧堆肥试验。试验结果表明,当堆肥底料的初始碳氮比为27:1,初始含水率为65%时,玉米芯、玉米秸杆和稻草均可作为调理剂与牛粪进行好氧堆肥,且可达到无害化要求。而采用粒径大、多孔、疏松的玉米芯作为调理剂,有利于通风供氧,堆体升温和降温均较快,高温持续时间长,堆料腐熟快,有利于加快堆肥的进程。  相似文献   

9.
城市污泥与稻草混合堆肥的最佳通风量优化研究   总被引:1,自引:0,他引:1       下载免费PDF全文
以城市污泥+稻草秸秆混合物料为研究对象,运用好氧堆肥方法,研究不同通风量对污泥堆肥过程的影响,测定了堆肥过程中温度、含水率、有机质含量和种子发芽指数的变化规律,分析了堆肥过程中通风与未通风之间的差异性。结果表明:(1)通风能够有效保证堆料升温和维持高温期,温度高达74.20℃,高温持续时间达到6 d,温度上升速率达到24.03℃/d。(2)通风条件下,含水率呈现先升高,后降低,然后趋于稳定的变化规律。(3)堆肥结束后,各处理有机质含量均达到国家标准。(4)通风能够显著影响种子发芽系数,各处理GI值的大小顺序为3号箱2号箱1号箱4号箱5号箱。当通风量为1.00 m~3/h,高温维持时间最长(6 d),种子发芽指数最高(84.25%),堆肥效果最理想。  相似文献   

10.
传统沼气工程的气肥联产工艺中,厌氧发酵产气与好氧发酵产肥互相独立,产气和产肥周期均较长、有机肥品质差,影响工程的高效运行。为缩短发酵周期、提高产气效率和有机肥品质,该研究将猪粪、鸡粪和秸秆混合进行15和30 d的干法厌氧发酵,将得到的沼渣添加秸秆辅料混合,分别设置65%和70%的发酵物料初始含水率进行15 d的高温好氧发酵,对比分析了不同厌氧-好氧发酵组合对产气和产肥的影响。结果表明:厌氧发酵阶段,混合物料的日产气率自发酵开始后逐渐上升,并在第8天达到最高峰,至第15天降至峰值的50%以下,此时累积产气量达到30 d发酵周期的71%,平均容积产气率达到1.91 m~3/(m~3?d),比发酵30 d平均容积产气率高41.5%。好氧发酵阶段,各处理组碳元素含量持续下降,氮元素含量先下降后增加,所得发酵产物均达到腐熟标准。采用15 d厌氧发酵所获得的沼渣进行好氧发酵,所得发酵产物的电导率、腐殖化程度和发芽指数均优于采用30 d厌氧发酵所获得的沼渣进行好氧发酵所得的发酵产物,同时总有机碳和总氮含量也较其分别提高了6.0%~21.7%和3.0%~10.2%,不同好氧发酵物料初始含水率对发酵产物的品质影响较不明显。因此,采用厌氧、好氧发酵周期均为15 d的组合,可缩短发酵周期、大幅提高产气效率和发酵产物的碳氮营养元素含量,有利于提高沼气工程运行效率和经济效益。  相似文献   

11.
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

13.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

14.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

15.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

16.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

17.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

18.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

19.
Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.  相似文献   

20.
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.  相似文献   

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