剩余污泥生态稳定化研究

利用中试规模的人工湿地对污泥进行了为期4 a的生态稳定化处理。系统占地80 m 2,填料层厚度为0.6 m,超高0.5 m,湿地植物选用芦苇。系统前2 a为污泥负荷期,后2 a自然稳定期。进泥TS、VS、含水率分别为平均22.34 g/L、7.76 g/L和97%,污泥负荷平均0.691 kg(TS）/m 2·d。在第1 a的系统调整期内,渗滤液COD去除率在60%～80%;而第2 aCOD去除率低于第1 a,为40％～50%;出水COD在100～200 mg/L之间。在负荷期内,随着运行时间的延长,也即随着污泥积存厚度的增加,渗滤液透过积泥层的时间变化不定,即渗滤液并非均匀下渗,而是部分渗滤液优先沿阻力最小的植物茎壁、根系以及积存污泥中大的孔隙向下流动。在第3 a和第4 a的自然稳定期内,污泥脱水较为充分,含水率分别降至平均34.3%和30.5%;污泥有机质含量分别降至平均16.8%和10.24%;稳定化污泥的全氮和全磷含量分别为平均0.98%和0.27%。对比发现,系统内植物量和植物营养成分都比野生植物高。     

生物絮凝吸附一级强化处理城市污水技术研究

通过进行生物絮凝吸附技术处理城市污水试验,着重讨论该技术在中、低污泥负荷条件下,水温10～14℃、pH6.4～6.7、水力停留时间1.5h、溶解氧2.0mg·L-1、污泥负荷0.55～0.10kgBOD5/kgMLSS·d时对BOD5、COD、SS的去除率;高污泥负荷条件下,水温11～29℃、pH5.8～6.4时影响COD、SS等污染物去除率的因素以及在根据回归正交试验所得水力停留时间、污泥负荷、溶解氧三因素推荐组合水平参数条件下高污泥负荷的运行效果。     

不同有机负荷下好氧颗粒污泥的特性

采用气升式内循环间歇反应器(IC-SBAR)培养好氧颗粒污泥,考察了有机负荷分别为1.58和14.12kg/(m3·d)时所形成的好氧颗粒污泥的特性。结果表明,在两种负荷下反应器对COD、TN和TP的去除率均分别达90%、80%和90%左右,但高负荷下培养的好氧颗粒污泥的沉降性能较好。     

油田含油污泥与芦苇共热解实验研究

以北方某油田湿地芦苇与油田某污水处理厂剩余污泥为对象,利用同步热分析仪及静态热解炉研究油田含油污泥及含油污泥-芦苇混合物的热解特性,将静态热解过程数据与同步热分析TG（热重分析）、DTG（微分热重分析）、DSC（差示扫描量热分析）曲线结合,计算了终止温度、产物量等。结果表明：不同含油污泥样品其产物生成率差别不大,热解TG、DTG和DSC曲线有较大差别,添加一定比例的芦苇可以使含油污泥热解过程变得匀速缓和,5%（质量比）的芦苇添加量可以使热解残渣恒重温度降低约25℃。混掺芦苇的样品残渣呈分散颗粒状,无聚结现象,对热解结焦将产生一定抑制作用。     

内循环UASB处理酒精废水及其颗粒污泥特性

针对传统UASB反应器在启动时颗粒污泥形成缓慢的问题,采用内循环UASB反应器作为厌氧单元对酒精废水进行处理。其以低负荷启动,启动完成后容积负荷为7.9 kg/(m3.d),对COD的去除率可达80%,整个试验阶段对NH3-N的平均去除率为16.38%。扫描电镜显示颗粒污泥中的优势菌开始为短杆菌,随着培养时间的延长则出现了球菌;而现有UASB反应器中颗粒污泥的优势菌为丝状菌。对沼气成分进行分析,CH4含量最高为81.61%,N2含量则随着颗粒污泥培养时间的延长由3.68%增加至18.59%。     

表面流芦苇湿地处理造纸废水的负荷估算

结合造纸废水生态处理现场试验和实际工程运行,测定了生态场区域的降雨量、蒸发量、苇田蒸散量,分析了苇田的水量与水质变化。结果表明,当进水COD浓度为800mg/L左右时,表面流人工芦苇湿地的蒸散负荷为0.9～1.12m3/(m2.a),COD面积负荷为0.65～0.786kg/(m2.a)。按照已投入运行的芦苇湿地面积为930hm2计算,则在满负荷运行的情况下芦苇湿地可消耗水量为(8.37～10.4)×106m3/a,去除有机物量为(5.58～7.29)×103t/a。     

低溶解氧SBR除磷工艺研究

试验研究了低溶解氧条件下SBR的除磷性能。结果表明,在全程低氧曝气的SBR系统内聚磷菌可得到富集,并出现了明显的放磷、过量吸磷现象。污泥负荷对COD去除率和除磷效率影响较大,除磷最佳的污泥负荷为0.26kgBOD/(kgMLSS·d),其时COD去除率为85%,除磷效率为96%,出水PO3-4-P<1.0mg/L;最佳污泥负荷下的污泥沉降性能良好,污泥负荷过高会导致非丝状菌污泥膨胀。     

氧化沟剩余污泥涡凹气浮(CAF)浓缩设备改进

指出了涡凹气浮工艺浓缩氧化沟剩余活性污泥存在的不足,并对其原因进行了分析,对涡凹气浮设备提出了改进措施,并研制出了1台MCAF 10型改进型涡凹气浮（MCAF）设备,用于对氧化沟剩余活性污泥的浓缩,絮凝剂投加量为1.0 kg FO4440SH/tDS,表面活性剂投加量为0.2 kg 1227/tDS时,采用CAF浓缩氧化沟剩余污泥时,最佳固体负荷为230 kgMLSS/m2·d,水力负荷为90 m3/m2·d,出水SS200～250 mg/L;采用MCAF浓缩氧化沟剩余活性污泥时,最佳固体负荷为270 kgMLSS/m2·d时,水力负荷为110 m3/m2·d,出水SS100～150 mg/L。试验表明：改进后的涡凹气浮设备更适宜于污泥浓缩。     

ICSTD反应器对剩余污泥的浓缩消化研究

采用新型内循环污泥浓缩消化反应器(ICSTD)对污水处理厂剩余污泥进行浓缩消化处理,系统运行稳定后对反应器内污泥特性进行研究。结果表明:在温度为30~35℃时,污泥产气率最高为1.6 m3/m3泥;所产沼气的甲烷含量在54%~75%之间;反应器运行期间污泥比阻从513×1012m/kg降低到202×1012m/kg,污泥脱水性能逐渐变好;对污泥所含元素进行分析,发现反应器消化效果较好,具有一定的脱氮效能。反应器内污泥优势菌属为鬃毛甲烷菌。     

接种污泥对UASB处理1,4-丁二醇生产废水的影响

采用UASB反应器处理1,4-丁二醇生产废水时,分别接种颗粒污泥、絮状污泥及两者的混合污泥,研究不同接种污泥对处理效果的影响。结果表明,接种颗粒污泥的反应器处理效果最好,但接种混合污泥时亦能取得较好的驯化及处理效果;接种颗粒污泥可以提高系统的最大COD容积负荷、抗污染负荷冲击能力及产气量,同时可降低挥发性脂肪酸的积累对微生物活性的抑制;在保持COD去除率>70%的条件下,3组反应器的最大COD容积负荷分别为4.70、3.25和4.50 kg/(m3.d)。     

Forms of polycyclic aromatic hydrocarbon in the formation of sewage sludge toxicity to Heterocypris incongruens

The aim of the present study was to evaluate to what degree polycyclic aromatic hydrocarbon (PAH) determines sewage sludge toxicity in relation to Heterocypris incongruens. Six differing sewage sludges with increasing contents of polycyclic aromatic hydrocarbons were selected for the present study. As well as total PAH content, the content of the potentially bioavailable fraction was also determined in the sewage sludges using a method of mild-solvent extraction (with n-butanol). The PAH content was also calculated in the sewage sludge pore water by the equilibrium partitioning method. The total PAH content in the sewage sludges studied were in the range 3.60 to 27.95 mg kg(-1). The contribution of the n-butanol extracted fraction was in the range 38.7 to 75.4%. In the group of individual PAHs, 4- and 5-ring compounds had the highest content in the potentially bioavailable group. H. incongruens mortality in the range 6.7 to 100%, depending both on the sewage sludge and the dose applied. An increase of the sewage sludge dose usually resulted in an increase in toxicity. At the highest dose, a 100% mortality of H. incongruens was found in half of the sludges. The lowest dose, irrespective of the sludge type, caused over 40% growth inhibition. However, the results obtained did not allow for the establishing of an unambiguous relationship between various sludge toxicity levels and the content of potentially bio-available PAHs. In some cases only, the extraction using n-butanol explained the high difference in toxicity despite a slight differentiation in the PAH content.     

Characteristics of sludge developed under different loading conditions during UASB reactor start-up and granulation

Sludge characteristics available inside the reactor are of vital importance to maximize advantages of UASB reactor. The organic loading rate and sludge loading rate applied during start-up are among the important parameters to govern the sludge characteristics. Effects of these loading rates on the characteristics of the sludge developed are evaluated in six laboratory scale UASB reactors. The sludge characteristics considered are VSS/SS ratio of the sludge, sludge volume index, specific gravity, settling velocity and metal contents of the sludge developed under different loading rates. The experimental results indicate that, for developing good characteristics sludge, during primary start-up from flocculent inoculum sludge, organic loading rate and sludge loading rate should be in the range of 2.0-4.5 kg COD/m3 d and 0.1-0.25 kg COD/kg VSS d, respectively (chemical oxygen demand, COD). Proper sludge granulation and higher COD removal efficiency will be achieved by these loading rates.     

接种蚯蚓堆肥处理压滤污泥的试验研究

选取上海桃浦污水处理厂的压滤污泥，采用不接种及接种赤子爱胜蚓（俗称红蚯蚓）两种方法对其进行模拟堆肥处理，通过检测pH值、挥发性固体、水溶性氮和C／N等理化参数以及毒性浸出浓度随时间的变化，系统地研究了利用蚯蚓堆肥处理污泥的可行性，并探讨了堆肥的机制。结果表明，接种赤子爱胜蚓后污泥的堆肥过程进行得比较顺利，经处理后污泥的pH值趋于中性，挥发性固体的含量降至44．10％，水溶性氮的含量增至18．34mg／kg，C／N值达2．56；Pb、Fe、Cr、Cd及Cu等5种金属的浸出毒性明显减小。     

Examination of arsenic(III) and (V) uptake by the desert plant species mesquite (Prosopis spp.) using X-ray absorption spectroscopy

This study describes the effects of Arsenic(III) and (V) on the growth and their uptake by the desert plant mesquite (Prosopis spp.). Seedlings were sown in agar-based medium containing a modified Hoagland's nutrient solution. After 1 week, the seedlings were transplanted to arsenic (As) treated agar media that contained 5 mgL(-1) of As either As(III) (As(2)O(3)) or As(V) (As(2)O(5)). The plants were harvested after 14 days of growth and sectioned into roots, stems, and leaves. After digestion, As concentrations in the roots, stems, and leaves were determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Our results showed that the As concentrations from As(V) were significantly higher than the As concentrations from As(III) in all portions of the plant. Plants exposed to As(V) concentrated (mg As kg(-1) d wt) about 770+/-191, 326+/-94, and 119+/-18 in roots, stems, and leaves, respectively. X-ray absorption spectroscopy (XAS) showed that As(V) was reduced to As(III) inside the mesquite plant. In addition, greater than 90% of the As(III) found in the mesquite plants was bound to sulfur ligands in the roots, stems and leaves.     

絮凝方式对净水厂排泥特性的影响

在不同的聚合氯化铝(PAC)投量下,考察了网格、折板和机械搅拌三种絮凝方式对沉淀池排泥周期和污泥静沉性能的影响。结果表明,当PAC投量20 mg/L时,网格絮凝池中矾花的沉降性能最好,相应的沉淀池排泥周期也最长,为10 h;当PAC投量为25 mg/L时,三者的排泥周期均为8 h左右,排泥水初始含固率也基本相同,此时,与网格池和搅拌池相比,折板池的污泥静沉性能最好、上清液浊度最低、浓缩后的污泥体积最小,表明该池型更适于对排泥水进行再絮凝沉淀。     

Operational strategies for an activated sludge process in conjunction with ozone oxidation for zero excess sludge production during winter season

A pilot-scale activated sludge system coupled with sludge ozonation process was operated for 112 days of a winter season without excess sludge wasting. The concept of this process is that the excess sludge produced is first disintegrated by ozone oxidation and then recirculated to a bioreactor in order to mineralize the particulate and soluble organic compounds. The basis of operation was to determine either the optimal amount of sludge in kg SS ozonated each day (SO) or the optimal ozonation frequency under the variable influent chemical oxygen demand (COD) loading and temperature conditions, since the ozone supply consumes costly energy. The optimal SO was obtained using the theoretically estimated sludge production rate (SP) and experimentally obtained ozonation frequency (n). While the SP was mainly subject to the COD loadings, sludge concentration was affected by the temperature changes in winter season. The optimal n was observed between 2.5 and 2.7 at around 15 degrees C, but it was doubled at 10 degrees C. Mixed liquor suspended solids (MLSS) concentration was leveled off at around 5000 mg/L in bioreactor at 15 degrees C, but the volatile fraction of MLSS was fixed around 0.7 indicating that there was no significant inorganic accumulation. Suspended solids (SS) and soluble COD in effluents kept always a satisfactory level of 10 and 15 mg/L with sufficient biodegradation. It was recommended to apply a dynamic SO under variable influent COD loadings and temperature conditions to the activated sludge system without excess sludge production for saving energy as well as system stabilization.     

PAH emission from the incineration of waste oily sludge and PE plastic mixtures

A batch-type, controlled-air incinerator was used for the treatment of oily sludge and polyethylene (PE) plastic mixtures. The concentration and composition of 21 individual PAHs (polycyclic aromatic hydrocarbons) in the raw wastes, flue gas (gas and particle phases) and ash were determined. Stack flue-gas samples were collected by a PAH stack-sampling system. Twenty one individual PAHs were analyzed primarily by a gas chromatograph and a gas chromatography/mass spectrometer. Due to incomplete combustion, PAH content in the feeding wastes have a strong influence on PAH emission in both stack flue gas and ash residue. With the oily sludge in the feeding waste mixtures, the input mass of lower molecular weight PAHs — Nap, AcPy, Acp, Flu, PA, Ant and FL — was contributed mainly by liquid diesel, while the input mass of higher molecular weight PAHs — Pyr, CYC, CHR, BbF, BkF, BeP, BaP, PER, IND, DBA, BbC, BghiP and COR — was primarily contributed by the oily sludge. For the distribution of individual PAH mean output mass, lower molecular weight PAHs — Nap, AcPy, Acp and Flu — have > 87% of their mass discharged by the stack flue gas. However, the higher molecular weight PAHs — Ant, FL, CHR, BbF, BeP, BaP, PER, IND, DBA, BbC, BghiP and COR — have significant mass fractions (>18%) discharged by the ash residue. The total-PAH output/input mass ratios were between 0.00103 and 0.00360 and averaged 0.00203. This result indicated that the depletion of PAH mass in the combustion process was very significant. The PAH content in the fuel during the combustion process is the control factor of PAH emission. The co-combustion of oily sludge with plastic is a potential method of reducing the PAH emission and of saving the consumption of auxiliary fuel.     

Occurrence of synthetic musks in Korean sewage sludges

Six polycyclic musks (PCMs) and five nitro musks (NMs) were analyzed in dewatered sludge samples from 13 municipal, 4 livestock and 1 pharmaceutical wastewater treatment plants (WWTPs) in South Korea. 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-(g)-2-benzopyran (HHCB; Galaxolide^®, Abbalide^®), and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN; Tonalide^®, Fixolide^®) were the two predominant PCMs in the sludge samples, at concentrations ranging from 0.52 to 82.0 mg/kg dry weight (dw) and 0.12 to 28.8 mg/kg (dw), respectively, suggesting the extensive use of these two PCMs in South Korea. Hierarchical cluster analysis (HCA) revealed the different usage patterns of PCMs between livestock cultivating farm and household. The levels of HHCB and AHTN in the effluent discharged from the WWTPs were lower than the threshold effect levels derived for fish, suggesting low potential risks to aquatic organisms. Nevertheless, the calculated discharge of synthetic musks (SMs) from sludge in each target WWTP ranged from 36 to 10,961 g/d. These results indicate the necessity of conducting monitoring studies in marine ecosystems due to ocean disposal of sludge, particularly focused on the two prevailing PCMs.     

好氧颗粒污泥技术用于味精废水处理的研究

以厌氧颗粒污泥为接种污泥,采用人工模拟废水在SBR反应器内培养好氧颗粒污泥,35 d后颗粒污泥成熟,反应器对COD和NH4+-N的去除率分别高于95%和99%。采用该反应器处理味精废水,当COD、NH4+-N的容积负荷分别为2.4、0.24 kg/(m3.d)时,对COD、NH4+-N和TN的去除率分别在90%、99%和85%左右,且颗粒污泥未出现解体的现象。以厌氧颗粒污泥为接种污泥、味精废水为进水,在与上述相同条件下培养好氧颗粒污泥,经过60 d的培养,反应器内的污泥以絮状污泥为主,该系统对COD、NH4+-N和TN的去除率分别为85%、99%和70%。