ASBR反应器厌氧氨氧化脱氮II:反应动力学

研究了ASBR厌氧氨氧化(ANAMMOX)反应器稳定条件下周期内的基质动力学特性以及过程抑制动力学特性,并得到适合描述上述特性的动力学模型.其中,稳态下周期内基质去除模型是首次被调查研究,研究发现,修正的Logistic模型和修正的Boltzmann模型相比Grau二级基质去除模型和修正的Gompertz模型而言,更适合描述稳态下周期内基质去除特性,并且通过模型得到了周期内任意t时刻下的出水总氮和总氮去除率预测公式.运用Haldane模型和Aiba模型建立了出水FA浓度与总氮去除负荷(TN RR)以及出水NO2--N浓度与总氮去除负荷(TN RR)之间的关系,结果表明:Haldane模型更适合用来描述基质抑制动力学特性,模型预测得到的出水FA和出水NO2--N抑制浓度分别为72.36mg/L和140.60mg/L.上述动力学模型的应用和动力学参数的获得可能会有助于ASBR反应器的优化设计和过程控制.     

火电厂液氨泄漏事故影响分析及对策研究

主要对火电厂液氨泄漏事故后对周围大气环境的影响进行了预测分析研究,并给出了相应安全对策。研究以陕西某电厂2×660MW燃煤机组为例,使用详实可靠的参数对该电厂可能发生的液氨储罐泄漏事故进行了不同气象条件下的风险模拟预测,并根据预测结果画出了可供应急救援参考使用的最不利气象条件下液氨储罐最大可信事故泄漏后不同时刻的影响范围动态图。研究还根据收集到的施工设计资料及参数对200-1000MW级火电厂的液氨泄漏进行了预测,给出各级别火电机组液氨泄漏事故后可能出现的最大致死半径范围。为降低火电厂液氨泄漏风险提出了相应的安全对策和应急救援要求,对避免和减少液氨中毒伤亡事故具有指导意义。     

Treatment of dye‐containing wastewater by sequencing batch reactor with powdered activated carbon addition

The process involving the combination of powdered activated carbon (PAC) and biomass in the aeration basin of conventional continuous‐flow activated sludge system, known as the PACT process, has proven to be effective for treating toxic pollutants present in industrial wastewaters. In view of the many advantages of sequencing batch reactors (SBR) operationally, the objective of this study is to evaluate the PACT process under SBR operation to treat wastewater containing Acid Blue 25 (AR) and Basic Yellow 2 dyes (BR). The SBR systems were operated with FILL, REACT, SETTLE and DRAW periods in the ratio of 0.25:3.75: 1.0:1.0 for a cycle time of 6 h. The average COD and AR removal efficiencies were 89% and 93%, respectively with PAC addition compared to 76% and 7%, respectively, without PAC addition. In the case of BR, the average removal efficiencies of COD and dye increased from 52% and 9% to 90% and 93%, respectively, with PAC addition. Kinetic study conducted for the REACT period showed that both dyes exhibited a very pronounced inhibitory effect on the activities of the microorganisms. The addition of PAC was capable of reducing the inhibitory effect of only BR but not AR on the microorganisms.     

Optimal parameters for Phanerochaete chrysosporium degradation of terephthalic acid wastewater

The optimal parameters for the degradation of pure terephthalic acid (PTA) wastewater by the white rot fungus Phanerochaete chrysosporium were investigated. The relative mathematical model, objective function equation, constraint equations, constraint conditions and computer program were established in the optimal method. The results showed that the optimal value of the reactor volume needed was 9798 m³. It could save 83.82% of the reactor volume, which was needed for the native bacterium YZ1. This optimal method is simple, useful and economical for average treatment plants. Using the optimal parameters and P. chrysosporium to design and operate the treatment process of PTA wastewater would increase the treatment efficiency and decrease the cost.     

ABR-BAF组合工艺处理制革综合废水

针对制革综合废水有机污染浓度高的特点,采用厌氧折流板反应器(ABR)-曝气生物滤池(BAF)新工艺处理,试验研究了ABR和BAF的启动以及水力停留时间(HRT)、有机负荷及其他因素对处理效果的影响。试验结果表明:ABR在HRT为12 h、水温25～37℃,BAF在HRT为2.5 h、DO≥2.0 mg/L的条件下,组合工艺对制革综合废水的COD平均去除率达88%,出水COD、SS、色度、总铬等指标达DB 44/26—2001《广东省地方标准水污染物排放限值》一级标准。     

竹炭固定床-聚氨酯流化床一体化反应器处理生活污水

为解决剩余污泥问题,研制了产泥率少的片状竹炭固定床-聚氨酯切块流化床一体化反应器,在保证流化床高浓度微生物的同时,维持竹炭固定床的好氧,兼性厌氧,以实现污泥的原位分解.试验采用南京林业大学紫湖溪生活污水,COD为140—170 mg·L-1,TP为1—2 mg·L-1,TN为35—45 mg·L-1,氨氮25—30 mg·L-1,SS为35—40 mg·L-1.反应器在第30 d启动成功.稳定的运行结果显示,水力停留时间为10 h时,反应器对有机物的去除效果较好,出水中COD、TN、TP、氨氮的浓度分别为19 mg·L-1、7 mg·L-1、0.47 mg·L-1、4.5 mg·L-1,去除率达到87%、76%、72%、84%,出水中各指标均满足《城镇污水处理厂污染物排放标准》(GB18918—2002)中的一级B排放标准.经竹炭固定床处理的出水SS浓度很低,长期维持在14 mg·L-1左右,二沉池出水中的SS平均浓度为12.7 mg·L-1,整个反应器对二沉池依赖性较小.     

在役柴油加氢装置HAZOP分析技术

柴油加氢装置属甲类火灾危险生产装置,为了保障其安全生产,实现事故早期预防,对其进行风险分析和安全评价势在必行.HAZOP分析方法是流程工业广泛使用的一种危险辨识和分析方法,具有较好的系统性和完备性.首先介绍了HAZOP分析方法的由来及应用情况,其次分析了在役装置HAZOP分析的难点,并提出了相应的建议,然后详述了在役装置HAZOP方法的分析流程.最后以中石油某石化公司在役柴油加氢装置为例进行了HAZOP分析,辨识出可能存在的安全隐患和潜在危险,对较高风险提出了必要的安全保护措施和合理的改进建议.结果表明,HAZOP分析是提高在役装置安全性的一种有效手段,其结果为装置安全管理提供了可靠的依据.     

厌氧迁移式污泥床反应器的水力特性研究

采用脉冲示踪法以NH4Cl作示踪剂,通过其在反应器中的停留时间分布来研究厌氧迁移式污泥床反应器(AMBR)的水力特性。反应器的结构决定了反应器的流态,从而控制着可能达到的处理效率。为优化设计反应器结构研究了反应器的构型、导流板与器壁间距对水力特性的影响。研究发现,反应器的流态介于推流式和完全混合式之间,带有导流板的反应器推流程度更大一些,而底部有孔的反应器推流程度弱,反应器的水力死区较小,均小于20%;导流板与器壁间距为8 mm时最佳。     

Effects of La,Ce on nitrogen removal in sequencing batch reactor

Batch experiments were conducted to study the short-term biological effects of rare earth ions (La³⁺, Ce³⁺) and their mixture on the nitrogen removal in a sequencing batch reactor (SBR). The data showed that higher NH⁺₄―N removal rate, total inorganic nitrogen removal efficiency, and denitrification efficiency were achieved at lower concentrations of rare earth elements (REEs) (<1mg/L). In the first hour of the aeration stage of SBR, the presence of REEs increased the total inorganic nitrogen removal efficiency and NH⁺₄―N removal efficiency by 15.7% and 10%―15%, respectively. When the concentrations of REEs were higher than 1mg/L, the total inorganic nitrogen removal efficiency decreased, and nitrate was found to accumulate in the effluent. When the concentrations of REEs was up to 50.0mg/L, the total inorganic nitrogen removal efficiency was less than 30% of the control efficiency with a high level of nitrate. Lower concentrations of REEs were found to accelerate the nitrogen conversion and removal in SBR.     

Co- or Ni-modified Sn-MnOx low-dimensional multi-oxides for high-efficient NH3-SCR De-NOx: Performance optimization and reaction mechanism

NH₃-SCR performances were explored to the relationship between structure morphology and physio-chemical properties over low-dimensional ternary Mn-based catalysts prepared by one-step synthesis method.Due to its strong oxidation performance,Sn-MnOx was prone to side reactions between NO,NH₃ and O₂,resulting in the generation of more NO₂ and N₂ O,here most of N₂ O was driven from the non-selective oxidation of NH₃,while ...