猪粪沼液的磁混凝预处理工艺优化及评估

以高悬浮物、高氮磷与高有机物的猪粪沼液为研究对象,采用磁混凝进行预处理,以浊度去除率为主要考察指标,结合单因素实验和正交实验,优化磁混凝工艺参数,并简要分析磁混凝机制及评估其作为沼液资源化利用的预处理工艺的效能。研究结果表明,优化的磁混凝条件是PAC、PAM、磁种的投加量分别为5 g·L~(-1)、120 mg·L~(-1)、3 g·L~(-1),转速为250 r·min-1。经磁混凝处理后,猪粪沼液的浊度、SS、COD、TP与PO34--P浓度降为2 235 NTU、 3.84 g·L~(-1)、10 302 mg·L~(-1)、133 mg·L~(-1)和62.58 mg·L~(-1),去除率分别为92.90%、84.42%、70.63%、91.90%和50.3%。同时,磁混凝对氨氮与K的去除率较低,分别为6.49%和16.12%,浓度分别为4 072.5 mg·L~(-1)和4 176 mg·L~(-1),利于后续的沼液资源化利用。磁种加载后在混凝过程中被絮体包裹,形成密实的磁絮体,显著提高了沉降性能,沉降时间由传统混凝的25 min降为5 min,同时污泥量显著减少。综上,磁混凝可高效削减沼液的悬浮物,且保留氮与钾等营养物质,促进沼液资源化利用。     

碱减量-印染混合废水的预处理研究

针对碱度大、COD高、组成复杂的碱减量-印染混合废水,采用高碱度下直接混凝再酸析相结合的方法进行预处理,取得理想效果.试验结果表明,在高碱度条件下先加入镁盐及少量高分子絮凝剂,可去除大部分可溶性及不溶性污染物;再通过降低pH的酸析法,能有效去除废水中的色度、浊度,大大降低COD.在MgSO4用量为800～1 500 mg/L,阴离子聚丙烯酰胺用量为2 mg/L,酸析pH小于3.0时,色度去除率达97%,COD去除率达92%,浊度去除率近100%.     

混凝沉淀-厌氧水解-A/O-混凝沉淀工艺处理印染废水

以苏南某化工园区集中污水处理厂为例,介绍了混凝沉淀-厌氧水解-A/O-混凝沉淀组合工艺处理印染综合废水.实际运行结果表明,系统的直接运行成本为0.755元/t废水,对COD、氨氮、总氮、总磷、SS和色度的平均去除率分别为77.7%、90.5%、49.6%、61.7%、68.9%和88.7%,其中色度基本达标,氨氮的达标...     

常规组合工艺-稳定塘-湿地系统处理印染废水

针对工业园区印染企业产生的印染废水和生活污水,采用独特的"常规组合工艺与‘植物稳定塘-人工湿地系统’联合工艺"对其进行集中统一处理,并考察了运行效果。数据结果表明,系统出水COD、BOD5、SS、色度、NH3-N和TP平均分别为63.2 mg/L、13.8 mg/L、5.0 mg/L、49倍、0.2 mg/L和0.4 mg/L,出水水质达到国家污水综合排放一级标准(GB8978-1996)。该工艺运行稳定,可有效去除废水中的COD、SS和色度,去除率均在90%以上。按日均处理量4×104m3计算,此工艺每年将削减COD排放近30万t。     

混凝法深度处理废纸造纸废水实验研究

按照烧杯实验方法,重点考察了pH值、混凝剂种类和投加量等因素对生化处理后废纸造纸废水混凝处理效果的影响。实验结果表明:PAC作为混凝剂,PAM作为助凝剂联合处理该废水时,能够取得较好的去浊率、SS、色度和COD去除率。混凝沉淀最佳运行条件为:废水pH为6.5,含铝量10%的PAC和2 g/L的PAM投加量分别为1 mL/L、0.5 mL/L,浊度从35 NTU降低到1 NTU,去除率达97.1%,SS从30 mg/L降低到7 mg/L,去除率达76.7%,色度从64倍降低到18倍,去除率达71.9%,COD从95 mg/L降低到44.8 mg/L,去除率可达52.8%,取得了较好的去除效果,达到国家造纸废水新排放标准限值。     

ClO2氧化/TiO2复合吸附剂协同体系处理印染废水的实验研究

利用ClO2 氧化/TiO2 复合吸附剂协同体系对处理实际印染废水进行了实验研究.结果表明,对于COD为750 mg/L、色度为250倍、SS为100 mg/L的1 000 mL印染废水,当溶液pH为4.0、ClO2 用量20 mg/L、TiO2 复合吸附剂用量2.5 g、反应时间和吸附时间分别为2、8 min时,处理后的废水COD＜100 mg/L、色度＜40倍、SS＜70 mg/L,达到了《纺织染整工业水污染物排放标准》(GB 4287-92)排放要求.并对两者的协同机理进行了理论上的探讨.     

臭氧-曝气生物滤池处理酸性玫瑰红染料废水

在实验室配制含酸性玫瑰红染料的印染废水,采用臭氧氧化-曝气生物滤池工艺开展处理试验.试验运行结果表明,臭氧氧化处理能提高模拟废水的可生化性,BOD/COD值由原水的0.18上升到0.36.经组合工艺处理后出水COD＜40 mg/L,色度40倍以下,SS约50 mg/L,处理效果良好.     

折流式水解-复合膜生物法处理印染废水的特性

应用折流式水解-复合膜生物法处理印染废水,COD与色度去除效果显著.组合工艺出水COD在100 mg/L以下,总去除率90%以上,出水色度为6倍以下,色度去除率达97%以上,达到纺织印染行业一级排放标准(COD≤100 mg/L,色度≤40倍).其中,ABR段的COD去除率在50%～65%,MBR段的COD去除率在78%～85%,COD的去除主要在MBR段,而色度去除主要在ABR段.此外,还对MBR段的HRT、污泥浓度、曝气量的影响进行了试验研究,结果表明,MBR段适宜的HRT为8～12 h,污泥浓度为3～8.6 g/L,气水比为23:1～31:1.     

不同铝系混凝剂处理印染废水

印染废水具有色度大、有机物含量高、水质变化大等特点,处理难度较大。对比了不同种类的混凝剂对印染废水的处理效果,结果表明,随着混凝剂投加量的增加,SS,色度和COD的去除率逐渐增大,当混凝剂的投加量达到80 mg/L时,4种混凝剂的混凝效果达到最优。Al_(13)在最优投加量下SS的去除率达到92.47%,色度去除率达到88.49%,COD的去除率达到80.47%。不同p H值条件下的混凝实验结果表明,随着p H值的升高,混凝效果逐渐提高,在p H值处于6.0~9.0的范围内均具有良好的混凝效果。在沉降的初始阶段,随着沉降时间的延长,4种混凝剂的混凝效果逐渐提高;当沉降时间超过10 min后,混凝效果没有明显的提高。Al_(13)形成絮体的沉降速度最快,11 min左右可以完成沉降,其他3种混凝剂需要在14 min左右完成沉降。     

混凝-氧化法处理印染废水

采用混凝 氧化法对印染废水进行处理 ,得出最佳混凝条件及氧化条件。实验结果表明 ,该法可使印染废水的CODCr与色度去除率分别达到 90 .2 %和 99.1%。该方法具有去除率高、操作方便、设备简单、不产生二次污染等优点。     

Clearance and recovery of Cd(II) from aqueous solution by magnetic separation technology

An effective method to actualize the recycling use of Cd(II) in industrial wastewater was developed by using the magnetic beads, which was modified with ethylenediamine. When the industrial wastewater was treated with these magnetic beads, the Cd(II) concentration in the solution was sharply reduced to the governmental standard (0.1 μg mL⁻¹) of China. Based on the monolayer adsorption of Cd(II) on the surface of these magnetic beads, the saturation capacity for Cd(II) reached to 68 mg g⁻¹ dried magnetic beads. On the other hand, the binding Cd(II) could be easily recovered in acid conditions and the recovery efficiency exceeded 99%. Thus, in the process of the wastewater purification, the recycling utilization of Cd(II) was realized. Additionally, the excellent capability of regeneration and recycling utilization of these magnetic beads made this technology much suitable for the large-scale application. Compared with the conventional purification methods, the rapid process, simple equipments, easy operation and high efficiency, brought this technology with great potentialities in the treatment of industrial wastewater.     

Synthesized magnetic nanoparticles coated zeolite for the adsorption of pharmaceutical compounds from aqueous solution using batch and column studies

The contamination of fresh water with pharmaceutical and personal care products (PPCPs) has risen during the last few years. The adsorption of some PPCPs namely, Diclofenac-Na, Naproxen, Gemfibrozil and Ibuprofen from aqueous solution has been studied, magnetic nanoparticles coated zeolite (MNCZ) has been used as the adsorbent. Batch adsorption experiment was conducted to study the influences of different adsorption parameters such as contact time, solution pH and PPCPs concentrations in order to optimize the reaction conditions. The removal was favored at low pH values. Thus, as pH turns from acidic to basic conditions these compounds were less efficiently removed. The initial concentration does not appear to exert a noticeable effect on the removal efficiency of the studied PPCPs at low concentrations, but it showed less removal efficiency during high concentration of PPCPs especially for Ibuprofen. The removal of Diclofenac-Na was independent on time, while the contact time was of significant effect on the adsorption of Naproxen, Gemfibrozil and Ibuprofen even though these compounds were removed up to 95% during 10 min using MNCZ. From the isotherm adsorption study, the adsorption of PPCPs studied on MNCZ was best fitted with Freundlich isotherm equation. Pseudo-second order model providing the best fit model with the experimental data. Column adsorption study was conducted to compare the removal efficiency of MNCZ with other processes used at drinking water treatment plants (DWTPs), MNCZ showed high removal efficiency (>99%) than other used processes at DWTPs.     

"磁种-高梯度磁分离"污水除磷技术的研究

通过添加磁种和混凝剂,用高梯度磁分离方法去除污水中正磷酸盐污染物,并对工艺参数进行了探讨.     

磁场强化臭氧液相传质

对不同种气液接触方式的臭氧气液传质性能进行了研究,考察了磁场作用下的臭氧进气量,液面高度以及液相p H值对微气泡臭氧传质效果的影响规律。实验研究表明,相同实验条件下,采用微气泡附加磁场(磁铁相吸)比底部曝气盘和微气泡发生器接触方式,液相中溶解的臭氧浓度分别提高了72.6%和11.4%,经过30 min后,水中溶解的臭氧浓度为8.91 mg/L,传质系数为0.2272 min-1,传质系数显著提高;在磁场的作用下的微气泡臭氧接触方式,臭氧气体流量较小的情况下,臭氧在液相溶解效率较高,液面高度h越高溶解的臭氧浓度越低,传质系数kLa值随着气液流量的增加而增加,但是随着液面高度h的增加而降低,液相的p H值也影响着传质效果,p H越低,水中溶解的臭氧浓度越高,传质系数越高。     

Identification of magnetic particulates in road dust accumulated on roadside snow using magnetic, geochemical and micro-morphological analyses

The aim of this study is to test the applicability of snow surveying in the collection and detailed characterization of vehicle-derived magnetic particles. Road dust extracted from snow, collected near a busy urban highway and a low traffic road in a rural environment (southern Finland), was studied using magnetic, geochemical and micro-morphological analyses. Significant differences in horizontal distribution of mass specific magnetic susceptibility (χ) were noticed for both roads. Multi-domain (MD) magnetite was identified as the primary magnetic mineral. Scanning electron microscope (SEM) analyses of road dust from both roads revealed: (1) angular-shaped particles (diameter ∼1-300 μm) mostly composed of Fe, Cr and Ni, derived from circulation of motor vehicles and (2) iron-rich spherules (d ∼ 2-70 μm). Tungsten-rich particles (d < 2 μm), derived from tyre stud abrasion were also identified. Additionally, a decreasing trend in χ and selected trace elements was observed with increasing distance from the road edge.     

油墨的凝聚-磁选研究

进行了油墨凝聚、磁选的研究,在废油墨中添加磁铁矿、油酸钠和煤油,使磁铁矿和非磁性油墨通过疏水性凝聚粘附在一起,再用磁选回收.研究表明,油酸钠和煤油作为凝聚剂是磁铁矿与油墨凝聚的前提和保证,磁种磁铁矿的加入确保了聚团的磁性能用于磁选.凝聚增大油墨聚团粒度和磁性.在油墨浓度为200g/L、磁铁矿用量2g/L、油酸钠用量为3...     

磁化学技术在水处理中的应用

对近年来磁化学技术在水处理中的应用做了比较全面的综述。介绍了磁化学技术的发展、磁分离技术的原理和分类及磁种强化处理废水 ,并对磁化学技术的应用领域进行了详细讨论。     

脉冲变频电磁场对水华鱼腥藻生长的效应

对脉冲变频电磁场作用下，扫描频率和磁感应强度的变化对水华鱼腥藻细胞活性和生长的影响进行了研究。结果显示，扫描频率从25~27 Hz增大到1~60 kHz时，磁场对藻细胞活性的抑制作用减小，但增大到60 kHz以上，磁场对藻细胞产生强烈抑制作用，累积水力停留时间4 min的藻样在48 h培养时间内已失去活性停止生长。扫描频率为50~100 Hz和1~60 kHz时，累积水力停留时间2 min的藻样，细胞受到磁场刺激生长加快；只有累积水力停留时间＞6 min，才表现出对藻活性的抑制作用。磁感应强度增大至120 G，磁场对细胞活性产生明显抑制作用，增大磁感应强度有利于对细胞活性和生长的抑制。     

锰磁活性炭的制备及其性能表征

以酶解提制烟碱后的烟渣和电解锰渣回收锰为原料，制备具备磁性和发达孔隙的活性炭。利用氮气吸附技术、红外光谱（FTIR）表征与分析了活性炭表面的孔隙结构和物化性质，考察了活性炭对亚甲基蓝的吸附性能和磁学性能。结果表明：以Mn／C基质废弃物为原料制得活性炭具有磁学性能；适量锰的添加有利于活性炭微孔的形成和发育；采用一步焙烧法有助于磁化物和活性炭基体相互作用形成化学键合，提高饱和磁化强度，实现废弃资源的充分利用。     

磁性多孔微球固定化硫酸盐还原菌的研究

以磁性多孔微球为载体，采用吸附法固载硫酸盐还原菌，用于磁性稳态流化床。通过扫描电镜等方法研究生物膜的组成，计算出反应器中磁性多孔微球的浓度、生物膜量和生物膜浓度等，并进行了磁性稳态流化床净化SO2废气初步实验。结果表明，MSFB反应器中的生物膜浓度为15．60g／L，生物膜厚度为105．60μm，MPM上固定的生物量高达109．80mg／g。磁性稳态流化床净化SO2废气，净化效率可达90％以上；并考察了pH和气液比对SO2吸收率的影响，这对进一步研究微生物法脱除烟气SO2具有重要意义。