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.     

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.     

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。     

不同乙酸钠/甘油比对好氧/延长闲置SBR除磷性能的影响

以合成废水为研究对象,以甘油和生活污水中常见的乙酸钠作为碳源,建立了5个好氧/延长闲置序批式反应器(乙酸钠/甘油比分别为1∶0、4∶1、1∶1、1∶4和0∶1),考察了各反应器长期运行过程中的除磷效果,并通过分析典型周期内磷及微生物体内各储能物质的变化,初步探究不同乙酸钠/甘油比对除磷性能的影响机理.研究表明,当乙酸钠/甘油比由1∶0逐渐降至4∶1和1∶1时,平均除磷率由90.1%升至92.5%、97.3%.乙酸钠/甘油比继续降至1∶4及0∶1时,系统除磷率降至65.7%、53.4%.当乙酸钠/甘油比为1∶1时,聚磷菌体内合成大量聚羟基脂肪酸酯(PHAs)(2.55 mmol·g-1,以每g VSS积累的C(mmol)计,下同),为后续磷的吸收及聚磷合成提供更多的能量,而以甘油作为单一碳源时,PHAs合成量最少(0.82 mmol·g-1),糖原合成量最大(2.56 mmol·g-1,以每g VSS积累的C(mmol)计).     

溶解氧对好氧/延长闲置SBR除磷性能的影响

以合成废水为研究对象,乙酸钠为外加碳源,考察不同溶解氧(DO)浓度下好氧/延长闲置(O/EI)序批式反应器的除磷效果,并通过分析典型周期内磷元素及微生物体内各储能物质的变化,探究DO浓度对O/EI工艺除磷性能的影响机制.结果表明,低DO浓度(1 mg·L-1)条件下,O/EI系统具有良好的除磷效果,除磷率高达96%,单位污泥除磷量为5.02 mg·g-1;而当DO浓度较高(4 mg·L-1)时,反应器内磷的去除率降至50%,单位污泥除磷量仅2.81 mg·g-1.研究表明,在DO浓度为1 mg·L-1时,微生物能合成较多聚羟基脂肪酸酯(PHAs),糖原的合成及利用较少,系统好氧吸磷量远高于其他反应器,并在闲置期释放出更多聚磷酸盐.可见,DO可通过影响微生物体内PHAs和糖原的合成及转化,闲置期释磷,好氧前期释磷及好氧吸磷,进而影响系统的除磷性能.