Process performance of anaerobic co-digestion of waste activated sludge and aquaculture sludge

The mesophilic anaerobic co-digestion (AcD) performances of waste activated sludge (WAS) and aquaculture sludge (AS) were studied. Mixtures of different compositions (0, 30, 50, 70 and 100 % of AS on the volume basis) were used as AcD substrates and tested via biochemical methane potential assay. The results showed that CH₄ production increased with AS/WAS ratio increment, and AS alone used as the substrate showed the maximum CH₄ yield, which was 8% higher than that achieved using WAS alone as the substrate. The CH₄ yield values were well fitted with the modified Gompertz model. The maximum methane potential (P₀) and maximum methane production rate (R₀) increased from 66.8 mL CH₄/g VS_fed to 70.9 mL CH₄/g VS_fed and from 4.40 mL CH₄/g VS_fed·d to 5.59 mL CH₄/g VS_fed·d, respectively, as the AS/WAS ratio increased from 0% to 100 %. In addition, lower levels of free ammonia and non-biodegradable organic matter contributed to the CH₄ production increasing with AS/WAS ratio increased.     

利用草菇棉籽壳废料栽培鸡腿蘑技术研究

进行了草菇棉籽壳废料 5个培养基配方栽培鸡腿蘑试验。结果表明 :鸡腿蘑培养料中草菇棉籽壳废料添加量为 3 0 %～5 0 %时 ,菌丝长满料袋时间较短 (18～ 19d) ,现蕾时间较早 (3 7d) ,出菇产量较高 (生物学效率为 73 .4%～ 77.3 % ) ,经济效益最好     

Analysing the Rockmass Permeation of a Low-medium Radioactive Waste Disposal Field

The fractures distribution and fracture rock mass permeation research is the premise condition that to study groundwater movement and pollutant migration in fracture rock mass in bed rock area, which includes the dominance orientation of fracture that groundwater fluxes in it, the brisk zone distribution of fracture water and the permeability calculation of rock mass. This paper mainly analyzes the fracture distribution and the dominance orientation of fracture and the permeability of a low-medium radioactive waste disposal field based on its rich geologic record. The following results are found through Statistical analysis and comparison calculation.The active zone of fractural water in bed rock is an active channel of active nucleus migration. Tthe headrace fracture of disposition have a dominant orientation. The penetrating coefficient tensor in bed rock fracture is also calculated.     

Analysis on the Disposal of the Industrial Solid Waste in the Three Gorges Region

The second step of water storage for Three Gorges Reservoir will be executed in Jue,2003. Because there is still a large quantity of industrial solid waste(ISW) dumped on the reservoir bottom where should be cleaned before water storage and wastes should be disposed. After a full investigation and analyze, the total amount of ISW in the Chongqing reservoir area is about 1.66 million tons. According the principles of safe, economical and reliable, this paper describes the ISW's treatment. The ordinary ISW which is harmless and non toxic after identification should be treated on-site, the ISW that exceeds the national standards should be removed and be disposed in the landfill, and the hazardous waste should be removed for disposition or storage.     

Fuzzy Assessment of MSW Disposal Technologies

Three disposal technologies have their own advantages, and meanwhile disadvantages. Facing a special case, it is difficult to choose a proper one. By integrated analysis to three main technologies, a relatively integrated index system is established. Then by means of fuzzy mathematics (quantify and synthetically analyze the index system, make it unitary) ,a final general assessing model is founded. Finally, the paper takes a planning MSW(municipal solid waste) plant as an example, uses a two-level fuzzy assessment model with three groups of assessing factors,which include economical, environmeutal and the other factors, and concludes that composting is the most appropriate choice.     

内浮顶罐下沉浮盘的改造

为提高内浮顶罐浮盘的抗沉能力，将钢制浮盘改造为铝质浮盘，叙述了具体的施工步骤及实际应用中应注意的事项。实践证明此改造方案效果较佳，可供借鉴。     

某拱顶油罐基础沉陷的修复与试水

通过对某泵站一座1×10~4m~3拱顶油罐基础沉陷修复方案和施工,及充水试验情况的介绍,说明此次油罐基础沉陷处理的方法得当,并收到良好的效果。此次储罐基础沉陷的处理方法简单,只切割底板,处理下沉地基省时、省力、节省费用。     

环舱式内浮顶油罐倾斜的处理

１４２号罐更新为环舱式内浮顶油罐后，罐体发生倾斜，由于浮盘较重，因此，现场分步正油罐罐体，先使倾斜一边的浮盘支柱落到罐的基础上，用空气吹砂法砂法矫正油罐主体；再用千斤顶顶起浮盘，修补罐底，然后试水，合格后恢复油罐附件，纠斜收到了预期效果。     

Changes in the genetic structure of Bacteria and microbial activity in an agricultural soil amended with tannery sludge

The application of tannery sludge to soils is a form of recycling; however, few studies have examined the impacts of this practice on soil microbial properties. We studied effects of two applications (2006 and 2007) of tannery sludge (with a low chromium content) on the structure of the bacterial community and on the microbial activity of soils. We fertilized an agricultural area in Rolândia, Paraná state, Brazil with different doses of sludge based on total N content, which ranged from 0 to 1200 kg N ha⁻¹. Sludge remained on the soil surface for three months before being plowed. Soils were sampled seven times during the experiment. Bacterial community structure, assessed by denaturing gradient gel electrophoresis (DGGE), was modified by the application of tannery sludge. Soon after the first application, there was clear separation between the bacterial communities in different treatments, such that each dose of sludge was associated with a specific community. These differences remained until 300 days after application and also after the second sludge application, but 666 days after the beginning of the experiment no differences were found in the bacterial communities of the lowest doses and the control. The principal response curve (PRC) analysis showed that the first sludge application strongly stimulated biological activity even 300 days after application. The second application also stimulated activity, but at a lower magnitude and for a shorter time, given that 260 days after the second application there was no difference in biological activity among treatments. PRC also showed that the properties most influenced by the application of tannery sludge were enzymatic activities related to N cycling (asparaginase and urease). The redundancy analysis (RDA) showed that tannery sludge’s influence on microbial activity is mainly related to increases in inorganic N and soil pH. Results showed that changes in the structure of the bacterial community in the studied soils were directly related to changes of their biological activity.     

酶催化氧化法处理水中的己烯雌酚

研究用辣根过氧化物酶(HRP)催化氧化法处理水中己烯雌酚(DES)的适宜工艺反应条件。试验考察了反应温度、p H和反应物反应计量比等对DES去除率的影响。结果显示,在p H4.5、25℃、[HRP]0/[DES]0为1.000 U/μmol和MH2 O2∶MDES(反应摩尔比)为1∶2的反应条件下,反应3 h,DES去除率可达到92.08%。研究表明,HRP催化H2O2氧化DES反应的适宜条件是:p H4.5左右,温度25℃左右,[HRP]0/[DES]0为1.000 U/μmol,MH2 O2:MDES宜大于0.5;过量H2O2抑制HRP催化活性;DES起始浓度越高,其去除速率越大;以底物DES去除速率表示的最大反应速率Vmax和米氏常数Km分别为74.63 mmol/(L·h)和46.75 mmol/L。