活性污泥中提取的藻酸作为铜吸附剂的研究

采用实验室培养的活性污泥提取藻酸并制备藻酸钙吸附剂,用于去除污水中的Cu2+,考察了其吸附和解吸性能及影响因素,并采用城市污水处理厂的剩余污泥进行验证.结果表明:pH值和藻酸钙投量对其吸附Cu2+有明显影响,当pH值为4、Cu2+初始浓度为100 mg/L、藻酸钙投量为0.7 g/L时,对Cu2+的平衡吸附量为41.96 mg/g;藻酸钙对Cu2+的吸附过程符合Langmuir模型;以盐酸为解吸剂,藻酸钙的解吸率可达到90%.实际剩余污泥可制备(203±11)mg/g的藻酸钙,对Cu2+的吸附量可达51.44 mg/g,而解吸率可达到94%.采用剩余污泥制备藻酸钙吸附剂,操作简单、成本低、对Cu2+的吸附高效、易于再生,具有工业应用前景.     

污泥吸附剂的制备及其对亚甲基蓝的去除研究

以城市污水厂脱水污泥、锯末和焦油的混合物为原料,选择ZnCl2为活化剂制备出过渡孔发达、强度大的优质污泥吸附剂(S-AC),借助BET、FTIR、DT等现代分析测试方法对污泥吸附剂进行表征,并通过吸附动力学、吸附等温线来研究污泥吸附剂的吸附性能;同时,将吸附剂应用于亚甲基蓝溶液的处理,并选择商品活性炭(AC)进行对照试验。结果表明,制得的污泥吸附剂的BET比表面积为358.0 m2/g;在试验浓度范围内,污泥吸附剂在温度分别为20、30和40℃时对亚甲基蓝的最大吸附量分别为57.13、59.37和61.79 mg/g,试验数据均符合Freundlich吸附等温方程;吸附剂的动力学数据均符合液膜扩散方程,液膜扩散为吸附过程的主控步骤。     

改性膨润土吸附剂的制备及其吸附性能的研究

本文以钠基膨润土为主要原料,选用壳聚糖作为改性剂,通过微波辐射进行改性,制备出壳聚糖改性膨润土吸附剂,并研究了其对Cr（VI）的吸附陛能和吸附工艺条件。结果表明,吸附剂对Cr（VI）具有较好的吸附性能,吸附的适宜工艺条件是：pH值为5-6,吸附时间为30min,吸附剂用量为12．0g／L。与单一的膨润土或壳聚糖相比,该吸附剂对Cr（VI）离子的吸附速度快、吸附能力强,并且具有成本低、应用范围广的优点,Cr（VI）的去除率可达N85％。     

硫酸活化市政污泥对氨氮的吸附研究

采用污水厂剩余污泥作为原料,以硫酸作为活化剂制备吸附剂,并将其应用到含氨氮废水处理中。进而系统地研究了溶液初始p H值、氨氮初始浓度、吸附时间等因素对硫酸活化市政污泥吸附氨氮的影响。结果表明,在吸附剂投加量为2 g/L、p H值为7.5、温度为303 K条件下,硫酸活化市政污泥对氨氮的吸附效果最佳。吸附动力学和热力学研究结果表明,吸附剂对氨氮的吸附过程可用准二级动力学模型(R2=0.998 6)来描述,且均符合Langmuir等温吸附模型、Freundlich等温吸附模型和Temkin等温吸附模型。由Langmuir等温吸附模型计算得到活化市政污泥对氨氮的最大吸附容量为44.84 mg/g。颗粒内扩散速率也是其吸附反应的限制因素,但不是唯一限制因素。该研究表明硫酸活化剩余污泥可以作为处理含氨氮废水的材料。     

微波法污泥活性炭的制备技术研究

以城市污水处理厂污泥为原料,考查了固液比、活化剂浓度、浸渍时间和活化时间等因素对氢氧化钾活化-微波加热制备污泥活性炭碘吸附值和产率的影响.在单因素试验的基础上进行正交试验,获得了此工艺制备污泥活性炭的最佳条件,即:固液比1g:1.5m L,氢氧化钾浓度0.40mol·L-1,浸渍时间24h,活化时间420s.此工艺条件下制备的污泥活性炭碘吸附值为537.63 mg·g-1,比表面积为354 m2·g-1,产率为74.09%,吸附性能和产率均优于传统方法制备的污泥活性炭.     

成型聚铝污泥吸附剂处理实际尾水及再生研究

成型聚铝污泥对阴离子具有良好的亲和吸附能力,可作为水处理领域的吸附剂。以印染废水尾水为处理对象,采用成型聚铝污泥吸附经Fenton氧化后的尾水,在pH值=4.0、FeSO_4·7H_2O用量为56 mg/L、H_2O_2用量为0.2 m L/L、反应时间为120 min、聚铝污泥吸附剂投加量为20 g/L、进水COD和TP分别为114和1.85 mg/L的条件下,出水COD和TP分别为44、0.46 mg/L。分别用酸碱和Fenton技术对吸附饱和的聚铝污泥进行再生试验,在pH值=3.0、FeSO_4·7H_2O投加量为40 mg/L的条件下,当H_2O_2投加量为0.3 m L/L时,Fenton氧化对聚铝污泥的再生率几乎可达到100%。     

好氧颗粒污泥吸附Zn2+的研究

以不同粒径的好氧颗粒污泥作为吸附剂吸附水中的重金属Zn2+,分析了颗粒污泥的粒径在不同初始Zn2+浓度和初始污泥浓度下对吸附效果的影响;同时以活性污泥为对照,对比研究了两种吸附剂对重金属Zn2+的吸附效果.研究发现,好氧颗粒污泥具有多孔结构,吸附过程满足一级可逆反应方程;小颗粒的吸附容量较大颗粒的高;颗粒污泥的解吸率均低于普通活性污泥的.可见,好氧颗粒污泥可作为含Zn2+废水的生物吸附剂.     

酸热改性凹凸棒石粘土对低硫汽油的脱硫效果研究

通过浸渍法制备改性凹凸棒石粘土汽油脱硫剂.用浓硫酸对产自甘肃临泽的凹凸棒石粘土进行酸改性和热活化,以改性后的凹凸棒石粘土为吸附剂,达到了对汽油进行吸附脱硫的目的.采用正交试验考察制备脱硫剂和吸附脱硫的最佳工艺条件.根据正交试验分析得到确定最佳试验工艺路线为A3B3C2D2E3,即酸化凹凸棒石粘土的硫酸浓度为2mol/L、热改性温度为90℃、吸附时间60min.最佳吸附脱硫工艺为脱硫剂用量4g/40mL、吸附温度为40℃、吸附时间为60min.凹凸棒石粘土经过改性后脱硫率明显提升,硫含量的质量分数从280μg/g降到54.43μg/g,脱硫率达到80.56％.     

改性沸石对废水中锰的吸附研究

采用吸附法去除水体中重金属锰,以NaOH对天然沸石改性,对含Mn的水体进行处理,通过单因素实验系统考察了改性沸石用量、吸附时间、初始浓度、温度对吸附效果的影响,研究结果表明在25℃,吸附剂用量为1.0 g,吸附时间120 min,对初始浓度为1.0 mg/L时,锰的去除率可达到99.3%,最大吸附容量达到9.93 mg/g。     

改性净水污泥负载纳米零价铁去除水中的Cr(Ⅵ)

以净水污泥为原材料,通过高温煅烧和盐酸活化制备得到改性净水污泥。利用液相还原法,以NaBH_4为还原剂还原Fe~(3+)合成改性净水污泥负载纳米零价铁(MWS-nZVI)吸附剂,将其用于去除水中的Cr(Ⅵ);并将MWS-nZVI与净水污泥负载纳米零价铁(WS-nZVI)作对比,考察了溶液pH值、吸附剂投加量和Cr(Ⅵ)初始浓度对吸附效果的影响;另外,采用扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和傅里叶变换红外光谱(FTIR)等表征手段,分析吸附材料的物理特性和化学组成。结果表明,MWS-n ZVI对Cr(Ⅵ)具有良好的去除效果,当投加量为0.3 g/L、pH值为2、Cr(Ⅵ)初始浓度为20 mg/L、反应时间为3.5 h时,对Cr(Ⅵ)的最大吸附量可达到26.0mg/g。表征结果显示,MWS-n ZVI的比表面积较大,且对纳米零价铁的负载效果更好。通过拟合发现,Freundlich吸附等温方程更适合模拟MWS-nZVI对Cr(Ⅵ)的去除过程。     

Kinetic and equilibrium studies of fluoride adsorption by a carbonaceous material from pyrolysis of waste sludge

The efficiency of the adsorption for fluoride by sludge from the treatment of starch industry wastewater was investigated. Batch experiments were conducted in order to determine the parameters that affect the adsorption process. The activation for waste sludge and specific surface area and porosity effects in enhancing the pyrolysis conditions were determined. The adsorption parameters of initial fluoride concentration, pH and adsorbent dosage were investigated with carbonaceous material. As a result of pyrolysis of samples treated with ZnCl₂ 1196 m²/g, the specific surface area was reached. Correlation coefficient of 0.99 and 12.75 mg/g adsorption capacity and adsorption isotherm model were revealed as convenient. Experimental results show that the adsorption of fluoride waste sludge will be effective in many ways in which the adsorbent is applied.     

Microwave-induced pyrolysis of sewage sludge

This paper describes a new method for pyrolyzing sewage sludge using a microwave furnace. It was found that if just the raw wet sludge is treated in the microwave, only drying of the sample takes place. However, if the sludge is mixed with a small amount of a suitable microwave absorber (such as the char produced in the pyrolysis itself) temperatures of up to 900 degrees C can be achieved, so that pyrolysis takes place rather than drying. Microwave treatments were also compared with those carried out in a conventional electric furnace, as well as the characteristics of their respective carbonaceous solid residues.     

Adsorbent obtained from CEPT sludge in wastewater chemically enhanced treatment

Chemically enhanced primary treatment (CEPT) in municipal wastewater treatment is particularly suitable for rapidly growing cities. The focus on CEPT process now might be the cost of chemicals and disposal of chemical sludge. In this study, the potential application of adsorbent made from CEPT sludge in CEPT wastewater treatment was investigated in various conditions, such as the adsorbent dosage, pH, and dosing modes of ferric chloride and adsorbent. It was found that sludge-derived adsorbent was a good way of sludge disposal while enhanced pollutants removal rate and reduced the fresh ferric chloride dosage. With the use of 10.0 mg L⁻¹ of ferric chloride and 0.6 g L⁻¹ of the adsorbent at the first stage simultaneously, the enhanced removal efficiencies of turbidity, UV₂₅₄, COD, TP were 83.3%, 52.3%, 48.8% and 89.0%, respectively. The experiments showed that ferric chloride dose was reduced about 50%. The pH played a significant role in coagulation and adsorption process.     

Characterisation of adsorbents prepared by pyrolysis of sludge and sludge/disposal filter cake mix

Copper and zinc removal from water (pH = 5.0) using adsorbents produced from slow and fast pyrolysis of industrial sludge and industrial sludge mixed with a disposal filter cake (FC), post treated with HCl, is investigated in comparison with a commercial adsorbent F400. The results show that a pseudo-second order kinetics model is followed. The Langmuir-Freundlich isotherm model is found to fit the data best. The capacity for heavy metal removal of studied adsorbents is generally better than that of commercial F400. The dominant heavy metal removal mechanism is cation exchange. Higher heavy metal removal capacity is associated with fast pyrolysis adsorbents and sludge/FC derived adsorbents, due to enhanced cation exchange. Improvement of Zn²⁺ removal via 1 N HCl post-treatment is only effective when exchangeable cations of the adsorbent are substituted with H⁺ ions, which boost the cation exchange capacity. Increase of temperature also enhances metal removal capacity. Fast pyrolysis sludge-based adsorbents can be reused after several adsorption-desorption cycles.     

硫酸铁改性活性炭催化微波降解对硫磷的研究

在有硫酸铁改性活性炭存在下,微波照射能使溶液中的对硫磷（乙基1605）迅速降解.对于总体积为25 mL、浓度为30 mg/L的乙基1605溶液,在改性活性炭加入量为0.6g/L的条件下,经微波照射2.5min后降解率达100%.而同样条件下采用未改性活性炭作催化剂,尽管对乙基1605的降解率也为100%,但很大一部分是由活性炭的强吸附作用造成的.这表明,在微波照射下改性活性炭的催化活性明显高于未改性活性炭的.另外,采用紫外-可见光谱和离子色谱技术探讨了微波照射时间、乙基1605初始浓度、活性炭用量、硫酸铁溶液的浓度和酸度、乙基1605溶液的酸度和活性炭使用次数对改性活性炭催化微波降解乙基1605的影响.     

两种微波—活性炭法对苯酚的去除效果及其效能比较

以活性炭为吸附剂和吸波栽体,对微波再生法和直接微波法去除水中的苯酚进行了对比试验研究.结果表明,在两种微波辐射方式下,活性炭都能有效去除水中的苯酚,其中微波再生法对活性炭的一次再生率可达96%,多次再生率为50%～70%;活性炭直接微波法对苯酚的去除率较单独活性炭吸附提高了7%～20%,在苯酚浓度较低(462 mg/L)时对其去除率最高达93%.试验结果还表明,微波再生法的除污效能指标(P)值普遍高于直接微波法,且活性炭可重复利用,是一种更为经济有效的微波方法.     

污泥改性活性炭技术及其应用进展

介绍了污泥的组成及性质、污泥活性炭吸附剂的制备方法及其在废水、废气治理中的研究和应用现状。污泥改性活性炭吸附剂技术在污泥处理领域有着广阔的应用前景，为我国污泥的资源化利用提供了新途径。     

Application of 'waste' metal hydroxide sludge for adsorption of azo reactive dyes

The capacity and mechanism of metal hydroxide sludge in removing azo reactive dyes from aqueous solution was investigated with different parameters, such as charge amount of dyes, system pH, adsorbent particle size, and adsorbent dosage. The three anionic dyes used were CI Reactive Red 2, CI Reactive Red 120, and CI Reactive Red 141, increasing in number of sulfonic groups, respectively. Only 0.2% (w/v) of powdered sludge (<75microm) achieved color removal from 30 mg l(-1) reactive dye solutions within 5 min without pH adjustment. The larger the charge amount of the dyes, the greater the adsorption (>90%) on the metal hydroxide sludge. The system pH played a significant role in the adsorption on metal hydroxides and formation of dye-metal complexes. The optimum system pH for dye adsorption was 8-9 which was close to the pH(zpc) of the sludge while the precipitation of dye-metal complexes occurred at system pH 2. The maximum adsorption capacity (Q degrees ) of the sludge for the reactive dyes was 48-62 mg dye g(-1) adsorbent. The Langmuir and Freundlich models showed that the higher charged dyes had a higher affinity of adsorption. The smaller particle size and the greater amount of adsorbent showed the faster process, due to an increase in surface area of adsorbent. Desorption studies elucidated that metal hydroxide sludge had a tendency for ion exchange adsorption of sulfonated azo reactive dyes. Leaching data showed that the treated water was nontoxic at a system pH above 5 or a solution pH above 2.     

Removal of Cu(II) and Cd(II) from aqueous solution by seafood processing waste sludge

Dried waste slurry generated in seafood processing factories has been shown to be an effective adsorbent for the removal of heavy metals from dilute solutions. Characterization of the sludge surface with scanning electron microscope and X-ray microanalyzer were carried out to evaluate the components on the sludge surface that are related to the adsorption of metal ions. Aluminum and calcium, as well as organic carbon are distributed on the surface of sludge. Alkalimetric titration was used to characterize the surface acidity of the sludge sample. The surface acidity constants, pKa1s and pKa2s, were 5.80 and 9.55, respectively. Batch as well as dynamic adsorption studies were conducted with 10(-5) to 5 x 10(-3) M Cu(II) and Cd(II). A surface complexation model with the diffuse layer model successfully predicted Cu(II) and Cd(II) removals in single metal solutions. Predictions of sorption in binary-adsorbate systems based on single-adsorbate data fits represented competitive sorption data reasonably well over a wide range of conditions. The breakthrough capacity found from column studies was different for each metal ion and the data reflect the order of metal affinity for the adsorbent material very well.