流化床厌氧反应器流化及反应特性研究

对流化床厌氧反应器的流化及反应特性进行研究,结果显示:床层实际初始流化流速umf为0.138～0.154cm/min,与理论计算值0.143 cm/min一致;在一定范围内,流速增大有利于反应量的提高,当流速为0.414 cm/min时,单位时间内的反应量达到最大,其值为4.66 mg/(L·min);适当提高流速有利...     

好氧及厌氧/好氧序批式工艺中磷化氢的释放

采用二次冷阱富集-气相色谱法作为磷化氢的检测方法,以高纯氮吹脱取样的方式,对好氧序批式工艺及厌氧/好氧序批式工艺中磷化氢的存在及其在工艺中的变化规律进行了研究。结果表明,两种工艺中均检测到磷化氢的存在。好氧序批式工艺中,磷化氢呈递减趋势,运行后期可间断性的检测到低水平（〈0.4 ng/L）磷化氢。厌氧/好氧序批式工艺中...     

IC＋A/O＋BIOFOR处理高浓度有机废水工程实例

江西某生物化工有限公司在生产乳酸的过程中产生大量高浓度有机废水,采用IC＋A/O＋BIOFOR联合工艺进行处理。当进水ρ（COD）平均为5 483 mg/L,ρ（NH3-N）平均为97.83 mg/L时,出水ρ（COD）平均为84 mg/L,去除率达98%;出水ρ（NH3-N）平均为12.07 mg/L,去除率为88%...     

Inhibition and recovery of nitrification in treating real coal gasification wastewater with moving bed biofilm reactor

Moving bed biofilm reactor (MBBR) was used to treat real coal gasification wastewater. Nitrification of the MBBR was inhibited almost completely during start-up period. Sudden increase of influent total NH3 concentration was the main factor inducing nitrification inhibition. Increasing DO concentration in the bulk liquid (from 2 to 3 mg/L) had little e ect on nitrification recovery. Nitrification of the MBBR recovered partially by the addition of nitrifying sludge into the reactor and almost ceased within 5 days. Nitrification ratio of the MBBR achieved 65% within 12 days by increasing dilute ratio of the influent wastewater with tap water. The ratio of nitrification decreased to 25% when influent COD concentration increased from 650 to 1000 mg/L after nitrification recovery and recovered 70% for another 4 days.     

絮凝细菌投加量对好氧颗粒污泥性能影响的研究

为研究絮凝细菌对好氧污泥颗粒化的影响,采用气升式内循环序批反应器,在培养好氧颗粒污泥过程中投加絮凝细菌,探讨其投加量对颗粒污泥的理化性能及生物降解效能的影响.结果表明,适量投加絮凝细菌能促进好氧颗粒污泥的形成,絮凝细菌投加量在0～20mL/L时,均可以培养出成熟的好氧颗粒污泥.絮凝细菌最佳投加量为10mL/L,此时颗粒化速度快,颗粒形成时间由未投加的42d缩短为35d,好氧颗粒污泥疏水性好,SVI稳定在40mL/g左右,沉降速度达35.82m/h,COD、氨氮和总磷的去除率分别为97.14%、84.49%和87.59%.而投加量为30mL/L时最终所形成的是白色污泥絮团,没有实现污泥颗粒化.     

高温ASBR处理水热改性污泥的工艺特性

采用高温ASBR处理水热改性污泥.结果表明,高温ASBR处理水热改性污泥的有机负荷(COD)由7.762kg/(m3·d)提升到13.106kg/(m3·d)后,会导致反应器内VFA的积累,pH和产气量的下降,反应器出现"酸化"现象.这种酸化现象属可恢复性酸化.系统恢复后,ASBR的有机负荷(COD)能达到10kg/(m3·d).高温ASBR在有机负荷(COD)为2.523、4.196、7.762、10.091kg/(m3·d)时的产气率(CH4/COD投入)分别为250、247、219、187mL.高温ASBR的有机负荷OLR与产甲烷速率MPR和COD产气率之间都呈现良好的线性关系,随着OLR的增加,产甲烷速率增大,COD产气率减少.     

Hydrodynamic characteristics of a four-compartment periodic anaerobic ba ed reactor

Periodic anaerobic baffled reactor (PABR) is a novel reactor based on the design concept of anaerobic baffled reactor (ABR). Residence time distribution (RTD) studies on both clean and working reactors at the same hydraulic residence time (HRT) of 2 d were carried out to investigate the dead spaces and mixing patterns in PABRs at different organic loading rates (OLRs) in various switching manners and frequencies.The results showed that the fraction of dead space in PABR was similar to that in ABR,which was low in comparison with other reactor designs.Dead space may be divided into two categories,hydraulic and biological.In RTD studies without biomass,the hydraulic dead space in the PABR run in an"every second"switching manner with T=2 d was the lowest whereas that in the PABR run in a T=∞(ABR) switching manner was the highest.The same trend was obtained with the total dead space in RTD studies with biomass no matter what the OLR was.Biological dead space was the major contributor to dead space but affected decreasingly at higher OLR whichever switching manner the PABR run in.The flow patterns within the PABRs were intermediate between plug-flow and perfectly mixed under all the conditions tested.     

Coordinability and consistency: Application of systems theory to accident causation and prevention

Recent works in the safety literature report several fruitful attempts to introduce mathematically rigorous results from systems and control theory to bear upon accident prevention and system safety. Previously, we discussed the implications on safety of the systems theoretic principles of coordinability and consistency, and we identified the lack of coordinability and/or consistency as fundamental failure modes in hierarchical multilevel systems. In this work, we further develop system safety analysis techniques based on these principles. We demonstrate that these principles not only provide a domain-independent vocabulary for expressing the results of post-mortem accident analyses, but they can also be applied to guide design and operational choices for accident prevention and system safety. We develop these ideas with the help of an illustrative case study. This case study represents a broad class of systems where operational policies and procedures of individual stakeholders in the system interact with physical processes such that new system behaviors emerge, and unanticipated safety issues arise. We argue, and illustrate our arguments using this case study, that the coordinability and consistency principles can be developed to deliver a threefold impact on accident analysis and prevention: firstly, these principles provide domain-independent procedural templates and vocabulary for post-mortem accident analysis. Secondly, these principles provide theoretical safety specifications to be met during system design and operation. Finally, these safety specifications can precipitate the formulation of a series of questions directly related to safety-oriented choices in the design, operation, and control of systems.     

生物活性炭塔中有机物沿程降解规律和降解动力学模型

上流式曝气生物活性炭塔(BAC)中的废水、空气从下往上流过生物活性炭层。为研究废水中有机物沿活性炭层的降解规律,生物活性炭塔由下至上共设有10个废水取样口,研究沿程各区间段对有机物的降解差异。试验结果表明在水力负荷为5.02~10.04 L/(m2·min),气水比为4∶1~6∶1时,COD、UV、色度的脱除主要集中在塔的中下部,占总脱除率70%以上。进水废水浓度对脱色率影响不大,对COD的脱除率有影响,进水废水浓度过大,脱除率降低。依据推流反应器模型,推导出废水净化塔中COD的降解动力学方程:Ce=Coexp(-2.406 4 H/L0.962)。     

新型双循环厌氧反应器的设计与水力特性研究

结合IC与EGSB的特点,同时根据厌氧处理理论,设计了新型双循环厌氧反应器,用于处理高浓度含有毒物质工业废水,并以Li Cl作为示踪剂,对该反应器不同水力停留时间(HRT)下的水力特性进行了研究。结果表明,在无循环时,各HRT下双循环厌氧反应器的C-θ曲线为不对称的单峰曲线。HRT为6,9,12 h时,反应器的死区比例分别为0.165,0.155,0.146。反应器呈推流流态,且随着HRT的增加,推流作用逐渐加强而完全混合作用逐渐减弱。当存在双循环时,在HRT为6,9,12 h的条件下,反应器第一反应区的σ2分别为0.249,0.179,0.113,第二反应区的σ2分别为0.135,0.112,0.106。双循环增大了反应器的返混程度,且与第一反应区相比,第二反应区更趋于推流式。