无机调理剂与表面活性剂联合调理对污泥脱水性能的影响

研究了CaO、PAFC联合表面活性剂预处理对污泥脱水性能的影响。以污泥滤饼含水率和比阻(SRF)作为评价污泥脱水性能的指标,通过测定污泥调理过程中胞外聚合物(EPS)含量、Zeta电位的变化来阐明污泥脱水性能的变化。实验结果表明,十二烷基二甲基苄基氯化铵(1227)的加入导致上清液中EPS含量发生变化,有效降低了SRF和滤饼含水率,提高污泥脱水性能。CaO、PAFC和表面活性剂的联合调理污泥比单独使用表面活性剂的效果更好,CaO、PAFC的投加不仅改善污泥脱水性能,并有助于减少表面活性剂的用量。污泥上清液中EPS及其各组分含量与污泥滤饼含水率、SRF均有较高的相关性,对污泥的脱水性能有重要贡献。实验中确定的最佳污泥调理条件是CaO投加量为66.67 mg·(g DS)?1、PAFC投加量为33.33 mg·(g DS)?1和表面活性剂投加量为56.25 mg·(g DS)?1,污泥滤饼含水率和SRF分别降至69.41%、0.294×1013 m·kg?1。     

无机调理剂与表面活性剂联合调理对污泥脱水性能的影响

研究了CaO,PAFC联合表面活性剂预处理对污泥脱水性能的影响。以污泥滤饼含水率和比阻(SRF)作为评价污泥脱水性能的指标,通过测定污泥调理过程中胞外聚合物(EPS)含量、Zeta电位的变化来阐明污泥脱水性能的变化。实验结果表明,十二烷基二甲基苄基氯化铵(1227)的加入导致上清液中EPS含量发生变化,有效降低了SRF和滤饼含水率,提高污泥脱水性能。CaO,PAFC和表面活性剂的联合调理污泥比单独使用表面活性剂的效果更好,CaO,PAFC的投加不仅改善污泥脱水性能,并有助于减少表面活性剂的用量。污泥上清液中EPS及其各组分含量与污泥滤饼含水率、SRF均有较高的相关性,对污泥的脱水性能有重要贡献。实验中确定的最佳污泥调理条件是CaO投加量为66.67 mg·(g DS)-1,PAFC投加量为33.33 mg·(g DS)-1和表面活性剂投加量为56.25 mg·(g DS)-1,污泥滤饼含水率和SRF分别降至69.41%和2.94×1012m·kg-1。     

化学调理剂对污泥脱水性能影响的研究

研究了表面活性剂TTAB、聚合氯化铝、阳离子聚丙烯酰胺对污泥脱水性能的影响,实验结果表明,它们都有助于改善污泥的脱水性能,表面活性剂TTAB、PAC和CPAM的投加量为0.28 g/L、4.5 g/L和90 mg/L时,污泥的沉降性能和脱水性能分别达到最佳,经表面活性剂调理后的污泥滤饼含水率可以达到70.33%,较PAC和CPAM调理的污泥脱水程度大幅提升,此外,还初步探讨了表面活性剂对污泥的作用机理,研究结果表明,表面活性剂主要通过分散污泥絮体的结构释放污泥絮体内部的结合水和溶出EPS来改善污泥的脱水性能。     

无机混凝剂与壳聚糖联合调理对污泥脱水的影响

研究了无机混凝剂(PAFC和PAC)与壳聚糖(CTS)联合调理对污泥脱水效果的影响。结果表明:联合调理污泥脱水效果明显优于单一混凝剂调理。当无机混凝剂PAFC和PAC投加量(以干污泥量计)分别为60 mg/g,CTS投加量(以干污泥量计)为3.0 mg/g时,PAFC+CTS、PAC+CTS调理污泥比阻比原泥分别降低了87.90%和84.93%,滤饼含水率降到76.3%和76.9%,污泥平均粒径从原来的8.70μm分别增大至59.07μm和54.69μm。相同投加量下,PAFC+CTS联合调理的污泥脱水效果优于PAC+CTS联合调理。     

典型表面活性剂对污泥脱水性能的影响研究

研究了十六烷基三甲基溴化铵(CTAB)和十二烷基苯磺酸钠(SDBS)对焦化污泥脱水性能的影响和作用机理。结果表明,CTAB的加药量为300 mg/L时污泥比阻(SRF)从1.04×10⁽¹¹⁾ s(11) s²/g降至2.76×102/g降至2.76×10⁽¹⁰⁾ s(10) s²/g,抽滤泥饼含水率(W_C)从83.97%降至77.91%;SDBS加药量为600 mg/L时,SRF只降至3.57×102/g,抽滤泥饼含水率(W_C)从83.97%降至77.91%;SDBS加药量为600 mg/L时,SRF只降至3.57×10⁽¹⁰⁾ s(10) s²/g,W_C为79.80%,SDBS改善污泥的脱水性能不如CTAB。经过表面活性剂调理后的污泥明显疏松。     

不同pH值下表面活性剂对污泥脱水性能影响的研究

通过测定比阻、滤饼含水率、污泥胞外聚合物(EPS)中蛋白质和多糖、污泥沉降体积和污泥毛细吸水时间(CST),研究不同pH值下表面活性剂对污泥脱水性能的影响,采用十二烷基硫酸钠(SDS)作为表面活性剂,在不同pH值下对污泥脱水性能进行了研究,考察了调理污泥的脱水速率、脱水程度、沉降性和滤失性4个方面。结果表明,在原污泥20 g、SDS投加量为污泥干重8%、浓硫酸调节溶液至pH 3的条件下,比阻0.44×10~9 m/kg、滤饼含水率65.10%、污泥胞外聚合物中含蛋白质526.2 mg/g和多糖87.7 mg/g、污泥沉降体积55.4 mL和污泥毛细吸水时间80 s,污泥脱水效果较好。     

Fenton试剂对剩余污泥脱水性能的改善

研究了利用Fenton试剂调理城市污水处理厂剩余污泥,通过测定污泥毛细吸水时间(CST)、污泥比阻(SRF)和泥饼含水率来表征污泥脱水性能的变化,分别考察了污泥初始pH、H2O2投加量、H2O2/Fe2+、反应温度和反应时间对污泥调理效果的影响。综合考虑,确定Fenton调理污泥的最佳条件为:pH=3、抽滤脱水和离心脱水H2O2最佳投加量分别为3 g/L和9 g/L、H2O2/Fe2(+质量比)最佳范围为8～12、反应温度50℃、反应时间60 min。对污泥离心上清液中胞外聚合物(EPS)含量的研究表明,Fenton调理后污泥上清液中蛋白质和多糖含量有大幅升高,说明Fenton试剂能有效氧化破解EPS,从而提高污泥的絮凝性,改善污泥的脱水性能。Fenton氧化后污泥颗粒粒径变小,比表面积增大。     

电芬顿调理污泥脱水性能影响因素研究

采用电芬顿技术对市政剩余污泥进行调理，以毛细吸水时间(CST)、污泥比阻(SRF)和污泥含水率为指标，研究了电芬顿调理污泥的主要影响因素(包括H₂O₂投加量、电压和反应时间)。结果表明，增大H₂O₂投加量和电压、延长反应时间均能有效改善污泥脱水性能。电芬顿调理污泥最佳条件为H₂O₂投加量0.12 mol/L，电压8 V，反应时间60 min。调理后污泥含水率下降18.8%。而过多的H₂O₂投加量、高电压和过长的反应时间均不利于改善污泥脱水性能。     

不同絮凝剂对剩余污泥水解和脱水特性的影响

研究了无机和有机絮凝剂对剩余污泥水解和脱水性能的影响。分别投加浓度为20g/L的CaO和CPAM（阳离子型聚丙烯酰胺）调节剩余污泥,溶出的有机质规律如下：溶解性COD（SCOD）的溶出量表现为CPAM>CaO>空白;溶解性蛋白质（SPN）的溶出量表现为CPAM>CaO>空白;溶解性碳水化合物（SPS）的溶出量表现为CaO>CPAM>空白。污泥的脱水性能指标——比阻（SRF）和滤饼含固率的变化分别为：SRF表现为CPAMCaO>空白。从SPN、SPS和SCOD的溶出量、比阻和滤饼含固率的变化说明：加入CaO和CPAM都能改善剩余污泥的水解和污泥脱水性能。     

电渗透/Fe-过硫酸盐氧化协同强化污泥深度脱水

利用电渗透和高级氧化技术,采用自制实验装置对城市污水处理厂的脱水污泥进行了脱水研究,系统研究了过硫酸盐投加量、铁盐与过硫酸盐比例、电压梯度、脱水时间和污泥厚度对污泥脱水的影响。结果表明,电渗透-高级氧化复合技术可以改善污泥的脱水性能,在污泥样品为140 g、过硫酸盐投加量为100（mg·g DS）^-1、Fe²⁺与过硫酸盐比例为1：1、机械压力为17.59 kPa、控制初始电压为11 V·cm^-1时,污泥的含水率可以降低至60%以下,与单独使用电渗透技术相比,泥饼具有更好的均匀性,便于后续的运输和安置。     

Fe(Ⅱ)活化过硫酸盐氧化破解剩余污泥

采用 Fe(Ⅱ)活化过硫酸盐,产生强氧化性硫酸根自由基(SO₄^-·),以污泥释放的溶解性COD(SCOD)、相对疏水性(RH)和污泥比阻(SRF)为表征,考察了SO₄^-·氧化破解剩余污泥强化脱水的影响因素,并解析了机理。结果表明:当初始pH为4.5,n(S₂O₈^2-)=2.2 mmol·(g VSS)^-1,n(Fe²⁺)=1.32 mmol·(g VSS)^-1,常温下反应3 h后,SCOD由66.5 mg·L^-1增加到472.3 mg·L^-1,RH由26.9%升高到41.1%,SRF由24.9×10⁸ S²·g^-1降低至4.5×10⁸ S²·g^-1;在此基础上利用响应面法,根据Box-Benhnken中心组合试验设计,以SRF为响应指标,优化条件为pH 4.27,n(S₂O₈^2-)=2.6 mmol·(g VSS)^-1,n(Fe²⁺)=1.59 mmol·(g VSS)^-1时,SRF为3.8×10⁸ S²·g^-1,泥饼含水率为72.7%。镜检发现,破解后污泥变为颗粒碎片状;傅里叶红外光谱显示污泥表面官能团对应的特征吸收峰强度有一定程度的减弱;热重分析表明无明显物理吸附水失重区。证实了在SO₄^-·作用下,污泥菌胶团结构破坏,溶胞释放了有机物,使表观疏水性更强,与水结合力明显减弱,脱水性得到了较大提高,有利于污泥减量化应用。     

污泥深度脱水调理剂对污泥干化过程中含硫气体释放的影响

采用5种复合调理剂改善污泥脱水性能,制得深度脱水泥饼。通过检测N₂气氛下,不同干化温度（100℃、200℃）,停留时间（30 min、60 min）时,不同调理脱水污泥含水率的变化情况,以及含硫气体的种类和释放量,探讨不同调理剂对干化过程中含硫气体释放特性的影响。结果表明,提高温度、延长时间都可以有效降低污泥的含水率;原污泥干化过程释放的主要含硫气体为H₂S和SO₂,其总量占含硫气体的82.4%;FeCl₃+CaO和H₂SO₄+FeSO₄+H₂O₂+CaO复合调理剂调理脱水泥饼在干化过程中SO₂释放量占原污泥释放量的40.3%和40.6%,H₂S则基本没有释放;H₂SO₄+FeSO₄+H₂O₂+CaO调理脱水污泥在100℃和200℃干化过程中的总硫释放量分别占原污泥总释放量的75.0%和45.6%,该复合调理剂在有效提高污泥脱水性能的基础上,能最大限度地抑制含硫气体的释放。     

A Study for Development of Real-Scale Thermal Filter Press Dewatering (TFPD)

Real-scale thermal filter press dewatering equipment (plate size: 630 mm × 630 mm) was installed and operated at a waterworks for one year in an attempt to achieve sludge reduction. During the period, the dewaterability was evaluated according to the seasonal sludge properties in order to compare the dewaterability of thermal dewatering and mechanical dewatering, as well as to determine the economics of thermal dewatering. According to the results, the winter season sludge showed a 36% decrease in water content and a two-thirds reduction in dewatering velocity compared to the summertime sludge. In addition, the dewatered cakes of the thermal filter press dewatering equipment showed a lower specific cake resistance and water content in the dewatered cakes than the mechanical filter press dewatering equipment, indicating superior dewaterability. This was attributed to the easier removal of the filtrate remaining in the capillary tubes due to thermal dewatering. The energy consumption for thermal dewatering was 300 kJ/dry solids (DS) kg. A comparison of the sludge dryers indicated that it is possible to produce dewatered cakes that consume less energy and can be recycled. According to the performance evaluation results, the real-scale thermal filter press dewatering equipment had high adaptability to the changes in seasonal sludge, showing excellent dewaterability compared to the mechanical filter press dewatering equipment, and was economical due to the lower energy consumption.     

Enhancement of biological fermented sludge dewaterability by inoculation of filamentous fungi Mucor circinelloides XY-Z and Penicillium oxalicum LY-1

Abstract

The two filamentous fungi of Mucor circinelloides XY-Z and Penicillium oxalicum LY-1 isolated from citric acid wastewater sludge collectively enhanced sludge dewaterability by 85.83% to achieve the lowest value of normalized sludge specific resistance (SRF) to 6.8?×?10¹¹ m·L/kg·g-TSS. The results showed that 75.77% of slime extracellular polymeric substances (EPS), 42.99% of protein in slime EPS and 60.27% of polysaccharide in LB-EPS were degraded during activated sludge treatment by the two mixed fungi of Mucor circinelloides XY-Z and Penicillium oxalicum LY-1, contributing to the conversion of 64.61% of bound water wrapped in EPS into free water, thereby improving activated sludge dewaterability.     

污泥含炭吸附剂的制备及其吸附模拟烟气中汞蒸汽的应用(英文)

The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Fourier transform infrared spectroscopy(FT-IR) ,and adsorption of nitrogen.The surface analysis showed that the carbonaceous adsorbent had good specific surface and porosity(394 m 2 ·g-1of BET surface,0.12 and 0.10 ml·g-1of microporous and mesoporous volume,respectively) .The oxygen functional groups such as OH,C O and C O were found on the surface by FTIR and XPS(X-ray photoelectron spectroscopy) .The adsorption of elemental mercury(Hg0) on the carbonaceous adsorbent was studied in a fixed bed reactor.The dynamic adsorption capacity of carbonaceous adsorbent increased with influent mercury concentration,from 23.6μg·g-1at 12.58μg·m-3to 87.9μg·g-1at 72.50μg·m-3,and decreased as the adsorption temperature increased,from 246 μg·g-1 at 25°C to 61.3μg·g-1 at 140°C,when dry nitrogen was used as the carrier gas.The carbonaceous adsorbent presented higher dynamic adsorption capacity than activated carbon,which was 81.2μg·g-1and 53.8μg·g-1respectively.The adsorption data were fitted to the Langmuir adsorption model.The physical and chemical adsorption were identified on the adsorbent.     

微波辐射对脱水城市污泥穿透性和脱水性的影响

研究了频率2450 MHz、功率500 W的微波在脱水城市污泥中的穿透性及辐射过程中污泥脱水性的变化. 结果表明,微波的穿透深度为8.7 mm,适宜的辐射可显著提高污泥的脱水性. 微波辐射5 min,上层容器中污泥离心后含水率由80.61%降至75.09%. 当温度高于约60℃时,污泥中微生物细胞开始大量破碎,胞内水释出,离心后含水率随温度升高而降低;高于88℃时,胞外聚合物含量无明显增加而亲水性下降,污泥脱水性迅速改善.     

Enhancing dewaterability of sewage sludge by the application of tween-20 during bioleaching: Performance evaluation and mechanistic study

Dewatering is recognized as an important method for treating sewage sludge before its disposal. In this paper, the nonionic surfactant Tween-20 was used for the first time to improve the dewaterability of sewage sludge during bioleaching. The specific resistance to filtration (SRF), water content (WC) and bound water content (BW) of the sludge cake were used to evaluate sludge dewaterability. The results indicated that a 1?g/L Tween-20 dosage with an inoculum ratio of 20%, a S⁰ dosage of 2?g/L and a FeSO₄?·?7H₂O dosage of 10?g/L provided oxidation efficiencies up to 100% for Fe²⁺ and 65.8% for S⁰. The SRF of the bioleached sludge decreased to as low as 0.81?×?10¹²?m/kg from the initial 12.6?×?10¹²?m/kg for raw sludge. A WC of 47.16% was achieved while 48.1% of BW was released during bioleaching. The results from this study indicate that adding of an appropriate amount of Tween-20 to sewage sludge is a promising method to enhance dewaterability by bioleaching.     

Spray-drying assisted layer-structured H2TiO3 ion sieve synthesis and lithium adsorption performance

A spray-drying assisted solid-state method to prepare spherical layer-structured H₂TiO₃ ion sieve (LSTIS) particles is reported herein. The effects of synthesis parameters (calcination temperature, calcination time, and the lithium-titanium molar ratio) on adsorption–desorption performance (the delithiation ratio, titanium dissolution loss, and the adsorption capacity) were investigated. The as-prepared LSTIS exhibited an equilibrium adsorption capacity of 30.08 mg·g^-1 (average of 25.85 mg·g^-1 over 5 cycles) and ultra-low titanium dissolution loss of less than 0.12% (average of 0.086% over 5 cycles). The LSTIS showed excellent selectivity toward Li⁺ in Na⁺, K⁺, Mg²⁺, and Ca²⁺ coexisting saline solutions where its adsorption capacity reached 27.45 mg·g^-1 and the separation factors of Li⁺ over the coexisting cations exceeded 100. The data suggests that the LSTIS is promising to competitively enrich Li⁺ from saline solutions.     

聚季铵盐调理污泥深度脱水过程与中试效能

采用聚季铵盐[P(DM-AM)]取代传统化学调理剂聚丙烯酰胺（polyacrylamide,PAM）,通过分析污泥脱水性能、胞外聚合物含量以及抽滤液水质指标,验证P(DM-AM)作为污泥调理剂的效果。结果表明,P(DM-AM)作为阳离子型高分子絮凝剂能够提高污泥的脱水性能,在最适投加量为0.4%～0.5%（按污泥干固量计算）时,毛细吸水时间（capillary absorption time,CST）和污泥比阻（specific resistance of sludge,SRF）分别下降48%和40%,污泥热值可达2686cal/g（1cal=4.18J）。当P(DM-AM)协同生石灰（CaO）和氯化铁（FeCl₃）作为调理剂调理污泥时,处理后的污泥水分去除率可升高55%左右,与污泥紧密结合型胞外聚合物（tightly bound-EPS,TB-EPS）中的多糖含量降低了74%,且污泥中Cl^-浓度约为92.3mg/gDS,较采用PAM调理的污泥下降约6%,可缓解污泥焚烧对焚烧炉腐蚀的影响。同时,P(DM-AM)调理污泥后,其抽滤液化学需氧量（chemical oxygen demand,COD）由2120mg/L降低至1941.8mg/L,可有效减轻污水处理厂运行负担。     

Removal of Cd（II） by Nanometer AIO（OH） Loaded on Fiberglass with Activated Carbon Fiber Felt as Carrier

A new nanometer material, nanometer AlO（OH） loaded on the fiberglass with activated carbon fibers felt（ACF） as the carrier, was prepared by hydrolytic reaction for the removal of Cd（II） from aqueous solution using column adsorption experiment. As was confirmed by XRD determination, the hydrolysis production loaded on fiberglass was similar to the orthorhombic phase AlO（OH）. SEM images showed that AlO（OH） particles were in the form of small aggregated clusters. The Thomas model was applied for estimating the kinetic parameters and the saturated adsorption ability of Cd（II） adsorption on the new adsorbent. The results showed that the maximum adsorption capacity of Cd（II） was 128.50 mg·g^-1 and 117.86 mg·g^-1 for the adsorbent mass of 0.3289 g and the adsorbent mass of 0.2867 g, respectively. The elution experiment result indicated that the adsorbed Cd ions was easily desorbed from the material with 0.1 mol·L^-1 HCl solution. Adsorption-desorption cycles showed the feasibility of repealed uses of the composited material. The adsorption capacities were influenced by pH and the initial Cd（II） concentration. The amount adsorbed was greatest at pH 6.5 and the initial Cd（II） concentration of 0.07 mg·L^-1, respectively. Nanometer AlO（OH） played a major role in the adsorption process, whereas the fiberglass and ACF were assistants in the process of removing Cd（II）. In addition, the adsorption capacities for Cd（II） were obviously reduced from 128.50 mg·L^-1 to 64.28 mg·L^-1 when Pb ions were present because Pb ions took up more adsorption sites.