生物流化床法处理污泥回流液的影响因素研究

将生物流化床工艺与活性污泥工艺相结合,以市政污水处理厂污泥回流液为研究对像。以0.3～0.45mm活性炭颗粒为载体对生物流化床中微生物进行培养、驯化,挂膜成功后,分别对生物流化床厌氧段和好氧段进行了单因素试验,得出进水的最佳pH值介于7.0～7.5,生物流化床厌氧段的最佳水力停留时间4.4h、最佳碳源为蔗糖,;缺氧段及好氧段的最佳水力停留时间2.69h、8.06h,曝气量0.5mL/min。在最佳工艺参数条件下进行污泥回流液脱氮除磷试验得出,此工艺可使总氮浓度为150.0mg/L,总磷浓度为59.0mg/L的污泥回流液的总氮浓度降低至65.19mg/L,此时的总氮去除率为56.54%;总磷的去除率较低。试验结果表明,该工艺对处理污泥回流液中氮磷具有一定的效果。     

SBR工艺在城市污水处理厂的应用

以SBR新工艺应用于抚顺市三宝屯污水处理厂为例,介绍了该工艺的主要性能特点、关键技术处理及工程设计思路,探讨了在实际应用中应关注的问题,并提出相应的措施。     

浮动填料生化法与活性污泥法比较研究

对沈阳市沈水湾污水处理厂的运行现状进行了概述,介绍了浮动填料生化法的工艺原理,通过对1号线浮动填料工艺和2号线活性污泥工艺运行参数的比较,表明浮动填料工艺在出水水质、抗冲击负荷等方面优于活性污泥法。     

Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion

Alkaline and ultrasonic sludge disintegration can both be used as pretreatments of waste activated sludge (WAS) for improving the subsequent anaerobic or aerobic digestion. The pretreatment has been carried out using different combination of these two methods in this study. The effect was evaluated based on the quantity of soluble chemical oxygen demand (SCOD) in the pretreated sludge as well as the degradation of organic matter in the following aerobic digestion. For WAS samples with combined pretreatment, the released COD was in high level than those with ultrasonic or alkaline treatment. When combined with the same ultrasonic treatment, NaOH treatment resulted in more solubilization of WAS than Ca(OH)2. For combined NaOH and ultrasonic treatments with different sequences, the released COD were in the order: simultaneous treatment > ultrasonic treatment following NaOH treatment > NaOH treatment following ultrasonic treatment. For simultaneous treatment, low NaOH dosage (100 g/kg dry solid), short duration (30 min) of NaOH treatment, and low ultrasonic specific energy (7 500 kJ/kg dry solid) were beneficial for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with the optimium parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than with ultrasonic (42.5%) or with NaOH pretreatment (43.5%) in the subsequent aerobic digestion at the same retention time.     

广州市污水污泥中的重金属及其农用探讨

分析了广州市6种污水污泥中重金属(Zn,Cu,Pb,Cr,Mn和Ni)质量分数及其存在形态,并对污泥农业利用过程中施用的最大量进行了估算.结果表明:广州不同来源污水污泥中.(Cu),w(Zn),w(Mn)和,(Ni)较高,变幅较大,而w( Ph )和w( Cr)低.除一种污泥中w(Cu)超标外,其他重金属基本符合国家农用控制标准(G1318918-2002),但所有污泥中重金属质量分数都超过广州市农田土壤平均值.不同重金属以及同一重金属在不同污泥中的形态分布也不同,其中Zn,Mn和Ni的潜在迁移性强,Cu和Cr中的还原态占有很大的比例,污泥中Pb主要以还原态和残渣态存在.根据广州市主要旱地赤红色土壤静态环境容量和动态环境容量计算表明,污泥农用过程中Cu和Zn是主要监控污染元素,不同来源污泥的最大施用量有明显差异.为保证土壤环境的安全,建议将Cu和Zn作为控制城市污水污泥农用过程中最高施用量的计算参考指标.     

Organic matter extracted from activated sludge with ammonium hydroxide and its characterization

In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH 3 ·H 2 O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics.     

Metal chlorides loaded on activated carbon to capture elemental mercury

Activated carbon (AC) was considered to be an effective sorbent to control mercury in combustion systems. However, its capture capacity was low and it required a high carbon-to-mercury mass ratio. AC loaded with catalyst showed a high elemental mercury (Hg0) capture capacity due to large surface area of AC and high oxidization ability of catalyst. In this study, several metal chlorides and metal oxides were used to promote the sorption capacity of AC. As a result, metal chlorides were better than metal oxides loaded on AC to remove gaseous mercury. X-ray diffractometer (XRD), thermogravimetric analyzer (TGA) and specific surface area by Brunauer- Emmett-Teller method (BET) analysis showed the main mechanisms: first, AC had an enormous surface area for loading enough MClx; second, Cl and MxOy were generated during pyrogenation of MClx; finally, there were lots of active elements such as Cl and MxOy which could react with elemental mercury and convert it to mercury oxide and mercury chloride. The HgO and HgCl2 might be released from AC’s porous structure by thermo regeneration. A catalytic chemisorption mechanism predominates the sorption process of elemental mercury. As Co and Mn were valence variable metal elements, their catalytic effect on Hg0 oxidization may accelerate both oxidation and halogenation of Hg0. The sorbents loaded with metal chlorides possessed a synergistic function of catalytic effect of valence variable metal and chlorine oxidation.     

低温时污泥膨胀对MBR中膜污染的影响

通过一体式膜生物反应装置考察了在低温条件下发生污泥膨胀过程中反应器的运行效果和膜污染的情况,并从微生物角度分析了引起膜污染的因素.结果表明,低温时COD上清液和出水平均去除率分别为85%和92%,发生丝状菌污泥膨胀后去除率变化不大.MBR中丝状菌污泥膨胀形成的过程中,污泥沉降性变差,丝状菌丰度（FI）由2增加到5,丝状菌伸出絮体形成网状结构.低温时膜操作压力随时间呈直线变化,膜组件的水力清洗周期为15 d.在丝状菌大量繁殖时缩短到7 d,膜污染严重.通过测定活性污泥的特性,发现膨胀污泥的胞外聚合物（EPS）总量是正常污泥的3倍,污泥絮体相对疏水性（RH）随FI的提高而增大.EPS和RH增大后会引起更多物质沉积到膜表面,使膜污染速率提高,膜的运行周期变短.进一步的分析表明,混合液粘度、Zeta电位、污泥絮体形态也是影响膜污染的因素.     

EGSB反应器中实现完全自营养脱氮与运行优化

同时接种好氧氨氧化污泥和厌氧氨氧化污泥启动EGSB反应器,培养完全自营养脱氮颗粒污泥,总氮去除速率达0.101 kg·(m³·d)^-1.基于边界层假设模拟颗粒污泥与液相主体间的传质过程,并将其与颗粒污泥内传质过程以及好氧氨氧化、厌氧氨氧化和亚硝酸盐氧化过程相耦合,建立了颗粒污泥完全自营养脱氮模型,应用实验结果对模型进行了验证.根据模拟结果对EGSB反应器运行条件进行优化,总氮平均去除效率由52%提高到61%,平均去除速率由0.103 kg·(m³·d)^-1提高到0.114 kg·(m³·d)^-1.     

泥水预分离MBR膜污染缓减效能研究

通过长期运行实验,进行了泥水预分离膜生物反应器（sludge/water pre-separation membrane bioreactor, S/W-MBR）与传统淹没式膜生物反应器（submerged membrane bioreactor, SMBR）对比研究,考察了污泥浓度、胞外聚合物含量（extracellular polymeric substances, EPS）及过膜阻力（trans-membrane pressure, TMP）随运行时间的变化规律及其对膜污染的缓减作用.结果表明,S/W-MBR与SMBR生物区的污泥浓度基本一致,而S/W-MBR膜区的污泥浓度较SMBR有显著降低.两者生物区的EPS含量均随运行时间的延长而增加,而S/W-MBR膜区的单位质量污泥的EPS含量始终保持在15 mg/g左右的较低水平.S/W-MBR比SMBR具有更好的缓减膜污染能力,在近90d的连续运行过程中,前者的膜组件仅需清洗2次,后者的膜组件清洗了5次.