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951.
Several starch/PVA/glycerol polymer blends were prepared by a solution casting technique and examined for biodegradation by composting over 45 days. Within this time frame, the starch and glycerol components were fully degraded, leaving the PVA component essentially intact. The lowest PVA content film (20%) was selected as a polymer with enough PVA to impart important physical characteristics, but also enough starch to be considered biodegradable. The film characteristics were further improved by surface modification with chitosan. This modification did not interfere with the biodegradation of the starch component. Furthermore, there was slight evidence that PVA biodegradation had been initiated in composted, surface modified starch/PVA blends.  相似文献   
952.
城市生活垃圾堆肥厂中的除臭技术   总被引:8,自引:1,他引:8  
冯明谦 《四川环境》2002,21(2):44-46
本文分析了垃圾堆肥厂臭气的来源,臭气的成份,介绍了脱臭技术及其设计参数,提出了在垃圾堆肥厂的设计建设中应重视臭气污染,除臭设施应同步建设的观点。  相似文献   
953.
自增强反应器在服役期间,其残余应力会因开停车循环载荷作用,温度、压力的波动及管内介质发生超温分解反应引起的热冲击等因素的作用而衰减,为了比较系统地探讨热冲击引起的自增强残余应力衰减机理和管材损伤机理,本从研究管式反应器受热冲击作用时的应力响应出发,建立相应数学模型,得到了应力随时间变化曲线,应力随半径变化曲线,通过分析得出了热冲击发生时产生的动态应力和异常高温是引起残余应力松弛和材质发生相变和老化的主要原因。  相似文献   
954.
Two series of starch-filled polyethylene films, consisting of high-density or low-density polyethylene and 0–20% starch, have been exposed for 60 days to a controlled composting environment. Evidence is reported that the oxidation of the polyethylene matrix is dependent upon the polyethylene type and content of starch.  相似文献   
955.
采用模拟含氮废水对自行设计制作的A/O生物膜反应器进行脱氮性能研究。研究结果表明:在水温为20~23℃、水力停留时间为18h、进水总氮质量浓度为61~78m g/L、曝气量为25L/min、进水COD分别为110~165m g/L和205~272m g/L的条件下,废水的COD去除率均在90%以上,硝化率分别为98%和95%,总氮去除率分别为50%和78%。采用荧光原位杂交技术对反应器各区域中的硝化细菌进行了检测。结果表明,反应器中的硝化菌主要为亚硝化螺菌属和硝化螺菌属,有少量亚硝化单胞菌属和硝化杆菌属存在。亚硝化菌和硝化菌在好氧区数量相对较多,在缺氧区数量相对较少。  相似文献   
956.
本文对常温(25℃±3℃)条件下低密度载体厌氧流化床(AFB)反应器处理高浓度有机废水进行了研究。实验结果表明:采用好氧预挂膜快速排泥法可加快反应器的启动,低密度载体可有效降低反应器运行能耗,有机物去除效果良好。  相似文献   
957.
嵩屿电厂烟气SCR脱硝工艺及特点分析   总被引:5,自引:0,他引:5  
介绍了厦门嵩屿电厂4×300MW燃煤机组烟气选择性催化还原法(SCR)脱硝工程所选用的工艺,分析了SCR脱硝系统的主要技术特点,为日益增多的同类型脱硝装置的工艺设计与设备选型提供一定的借鉴。  相似文献   
958.
A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier.Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Pxl, Bacillus sp.Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization.The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances),which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm~2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.  相似文献   
959.
Based on the developed neural-fuzzy control system for anaerobic hybrid reactor (AHR) in wastewater treatment and biogas production, the neural network with backpropagation algorithm for prediction of the variables pH, alkalinity (Alk) and total volatile acids (TVA) at present day time t was used as input data for the fuzzy logic to calculate the influent feed flow rate that was applied to control and monitor the process response at di erent operations in the initial, overload influent feeding and the recovery phases. In all three phases, this neural-fuzzy control system showed great potential to control AHR in high stability and performance and quick response. Although in the overloading operation phase II with two fold calculating influent flow rate together with a two fold organic loading rate (OLR), this control system had rapid response and was sensitive to the intended overload. When the influent feeding rate was followed by the calculation of control system in the initial operation phase I and the recovery operation phase III, it was found that the neural-fuzzy control system application was capable of controlling the AHR in a good manner with the pH close to 7, TVA/Alk < 0.4 and COD removal > 80% with biogas and methane yields at 0.45 and 0.30 m3/kg COD removed.  相似文献   
960.
The feasibility of using anaerobic ba ed reactor (ABR) as onsite wastewater treatment system was discussed. The ABR consisted of one sedimentation chamber and three up-flow chambers in series was experimented under di erent peak flow factors (PFF of 1 to 6), superficial gas velocities (between 0.6 and 3.1 cm/hr) and hydraulic retention times (HRT) (24, 36 and 48 hr). Residence time distribution (RTD) analyses were carried out to investigate the hydraulic characteristics of the ABR. It was found that the PFF resulted in hydraulic dead space. The dead space did not exceed 13% at PFF of 1, 2 and 4 while there was 2-fold increase (26%) at PFF of 6. Superficial gas velocities did not result in more (biological) dead space. The mixing pattern of ABR tended to be a completelymixed reactor when PFF increased. Superficial gas velocities did not a ect mixing pattern. The e ects of PFF on mixing pattern could be minimized by higher HRT (48 hr). The tank-in-series (TIS) model (N = 4) was suitable to describe the hydraulic behaviour of the studied system. The HRT of 48 hr was able to maintain the mixing pattern under di erent flow patterns, introducing satisfactory hydraulic e ciency. Chemical oxygen demand (COD) and total suspended solids (TSS) removals under all flow patterns were achieved more than 85% and 90%, respectively. The standard deviation of e uent COD and TSS concentration did not exceed 15 mg/L.  相似文献   
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