人工湿地基质中腐殖质的积累与分布特点

腐殖质来源于生物残体的降解,可参与多种污染物迁移转化,具有重要环境生态效应.本研究以常见的水平潜流和垂直流2种系统为研究对象,探讨了以无机基质为主构建的常规人工湿地中腐殖质的积累与分布特点.研究结果表明,随着污水处理运行,水平潜流和垂直流人工湿地中,大部分基质中腐殖质全碳量均有增加,水平潜流系统含量在1.7～ 18 g/kg,垂直流系统在1.9 ～7.5 g/kg;胡敏素是各系统腐殖质的主体组成,含量最高,水平潜流系统含量在1.55～17.22g/kg,垂直流系统在1.43 ～7.21 g/kg.腐殖质另外2种组分,富里酸和胡敏酸碳含量都比较低,水平潜流系统富里酸碳含量在0 ～0.68 g/kg,胡敏酸碳含量0.008 ～0.26g/kg;垂直流系统富里酸碳含量在0.015 ～0.38 g/kg,胡敏酸碳含量在0.05～0.15 g/kg,各系统中富里酸碳含量均高于胡敏酸碳含量;各系统中,根系基质腐殖质全碳及3种组分含量都显著高于非根际基质;不管是水平潜流还是垂直流,低水力负荷系统的比高水力负荷系统更高.     

热处理时间对餐厨垃圾高温干式厌氧发酵的影响

餐厨垃圾中有机物大部分以大分子的形式存在,对其进行热处理,破坏大分子有机物的存在形式,将会影响其干式厌氧发酵的过程。实验对餐厨垃圾进行了热处理(100℃),处理后将其在含固率(TS)20%、接种率25%的条件下进行高温55℃厌氧发酵。实验结果表明,热处理后,餐厨垃圾的理化性质发生显著变化,累计产气量、TS和VS的去除率均增大。当热处理时间为15 min时,餐厨垃圾的SCOD值最高,为59.49 g/L,比未处理时提高了3.3倍。同样该条件下,累计产气量也最高,为2 782.8 m L,与未处理相比累积产气量提高58.30%,第二产气高峰比未处理提前3天。各发酵瓶发酵前后TS、VS去除率的变化趋势与累计产气量的变化基本一致,累计产气量越大,TS、VS的去除率越大。     

改性糠醛渣吸附脱硫废水中钙离子

石灰石-石膏法烟气脱硫技术中石灰石利用率低导致钙流失严重,为实现脱硫废水中Ca2+的资源化利用,进行糠醛渣改性和Ca2+的吸附特性研究。实验结果表明,利用H3PO4改性后的糠醛渣对脱硫废水中Ca2+具有较高的吸附率;在振荡的前30 min吸附率上升极快,至90 min时基本达到平衡吸附量;对Ca2+浓度对吸附率影响研究结果表明,平衡吸附量与平衡浓度关系符合Langmuir等温吸附方程;在初始Ca2+浓度为300 mg/L的溶液中加入3 g吸附剂,温度30℃条件下振荡90 min,平衡吸附量为8.41 mg/g。     

中型污水处理厂中药物和个人护理品的分布与去除

为了解15种药物及个人护理用品(PPCPs)在中小型污水处理厂中的分布及其去除效果,采用液相色谱-串联质谱(LC-MS/MS)技术对3座A2/O工艺的污水处理厂水样进行分析研究。结果显示,除普萘洛尔、吉非罗平和吲哚美辛在3座中小型污水处理厂各个工艺单元中均未被检出外,其余12种目标化合物的检出频率在90%~100%之间。进水水样中PPCPs的平均检出浓度为2 285.4 ng/L,其中咖啡因(CF)的平均检出浓度最高为973.3 ng/L,酮洛芬(KP)的平均检出浓度次之为844.7 ng/L,两者之和占进水水样中PPCPs平均含量的79.5%,表明污水处理厂的主要污染物为CF和KP。3座污水处理厂对CF的去除效果最为显著,平均去除率为95.3%,对15种PPCPs总去除效率在39.3%~82.8%之间。     

燃煤锅炉烟气脱硫废水处理技术研究进展

对目前国内外燃煤锅炉烟气脱硫废水处理的多种方法，如混凝－沉淀法、流化床法、人工湿地法、单质铁法、微滤膜法、生化法和改良混凝－沉淀法等进行了分析评述。研究发现，开发技术集成度大、流程短、药剂种类和用量少、一次性投资以及运营费用低的工艺技术是未来发展的方向，而改良混凝－沉淀法脱硫废水处理技术符合要求，是一项值得加强应用研究和推广的新技术。     

污水处理移动床生物膜反应器悬浮载体研究进展

介绍了移动床生物膜反应器(MBBR)中悬浮载体的种类和特性,讨论了对其性能的影响因素,总结了当前悬浮载体改性技术及性能评价的方法,并对后续研究提出了建议。     

Variability of pesticide residues in cauliflower units collected from a field trial and market places in Greece

To estimate the variability of pesticide residue levels present in cauliflower units, a total of 142 samples were collected from a field trial of a cooperative farmer, and 120 samples were collected from different market places in Thessaloniki, Greece. The collected samples were extracted using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction technique, and the residues were determined by liquid chromatography–tandem mass spectrometry. The developed method was validated by evaluating the accuracy, precision, linearity, limit of detection (LOD), and limit of quantification (LOQ). The average recoveries for all the analytes, derived from the data of control samples fortified at 0.01, 0.05, 0.1, and 0.2 mg/kg, ranged from 74 to 110% with a relative standard deviation of ≤8%. The correlation coefficient (R²) was ≥0.997 for all the analytes using matrix-matched calibration standards. The LOD values ranged from 0.001 to 0.003 mg/kg, and the LOQ was determined at 0.01 mg/kg for all the sought analytes. The matrix effect was found to be at a considerable level, especially for cypermethrin and deltamethrin, amounting to +90% and +145%, respectively. For the field samples, the unit-to-unit variability factors (VFs) calculated for cypermethrin and deltamethrin were 2.38 and 2.32, respectively, while the average VF for the market basket samples was 5.11. In the market basket samples, residues of cypermethrin, deltamethrin, chlorpyrifos, and indoxacarb were found at levels ≥LOQ and their respective VFs were 7.12, 5.67, 5.28, and 2.40.     

厌氧系统中碱处理对污泥减量的影响

碱解预处理污泥和原污泥按一定比例进行混合后,投入厌氧反应器中进行消化,研究其对污泥减量化的影响。结果表明,该处理既可以提高污泥减量率,又能改善污泥厌氧消化性能,提高污泥产气量。当碱处理污泥和原污泥混合比为1∶3时,在混合初期由于稀释作用和水解中和作用,溶液的pH能迅速恢复到中性。SS减少48%,较对照组提高了10%;SCOD减少约80%,较对照组提高20%,而空白对照组因未发生溶胞作用,各参数值均处于较低水平,降解率也维持在较低水平。     

游泳池中隐孢子虫卵囊替代物的去除

隐孢子虫是常见的球状寄生虫。接触含有隐孢子虫卵囊的水体可致隐孢子虫病,主要的临床表现为腹泻,严重者可致死。游泳池是主要的传播场所。采用容积为5 500 L的游泳池,进行隐孢子虫卵囊替代物的修复模拟实验,研究在游泳池条件下絮凝沙滤技术对直径为4.5μm隐孢子虫卵囊替代物的去除效果。实验结果表明,氯化铝剂量为0.1 mg/L,沙滤料高度为30 cm,内循环流速为11.5 L/min,对隐孢子虫卵囊替代物去除率在90%以上。该技术对浊度具有较好的处理效果,当进水浊度降低且接近于出水浊度时,系统进入稳定运行阶段,对虫卵囊替代物去除率可以达到96%。     

Multi-response optimization of Fenton process for applicability assessment in landfill leachate treatment

Fenton process, as a pretreatment method, was found to be effective in the primary treatment of mature/medium landfill leachate. However, the main problem of the process is the large amount of produced sludge that requires an accurate feasibility evaluation for operational applications. In this study, the response surface methodology was applied for the modeling and optimization of Fenton process in three target responses, (1) overall COD removal, (2) sludge to iron ratio (SIR) and (3) organics removal to sludge ratio (ORSR), where the latter two were new self-defined responses for prediction of sludge generation and applicability assessment of the process, respectively. The effective variables included the initial pH, [H₂O₂]/[Fe²⁺] ratio and Fe²⁺ dosage. According to the statistical analysis, all the proposed models were adequate (with adjusted R² of 0.9116–0.9512) and had considerable predictive capability (with prediction R² up to 0.9092 and appropriate adequate precision). It was found that all the variables had significant effects on the responses, specifically by their observed role in dominant oxidation mechanism. The optimum operational conditions obtained by overlay plot, were found to be initial pH of 5.7, [H₂O₂]/[Fe²⁺] ratio of 17.72 and [Fe²⁺] of 195 mM, which led to 69% COD removal, 2.4 (l sludge/consumed mole Fe²⁺) of SIR and 16.5 (gCOD removed/l produced sludge) for ORSR in verification test, in accordance with models-predicted values. Finally, it was observed that [H₂O₂]/[Fe²⁺] ratio and Fe²⁺ dosage had significant influence on COD removal, while Fe²⁺ dosage and [H₂O₂]/[Fe²⁺] ratio had remarkable effects on SIR and ORSR responses, respectively.