污泥基吸附剂对亚甲基蓝和环丙沙星的吸附性能研究

亚甲基蓝和环丙沙星是水体中2种污染物, 对生态环境有潜在危害. 本文以市政剩余活性污泥为原料, 氯化锌为活化剂热解制备污泥基吸附剂, 研究盐酸酸洗浓度、氯化锌浓度、热解温度、热解时间等对污泥基吸附剂吸附水中亚甲基蓝和环丙沙星性能的影响. 结果表明 (1)污泥基吸附剂对亚甲基蓝的吸附性能随盐酸酸洗浓度的增大而增加, 对环丙沙星的吸附性能则随盐酸酸洗浓度的增大呈先降后增趋势, 两者均在1.500mol·L-1盐酸浓度下取得最优值. (2)污泥基吸附剂对亚甲基蓝和环丙沙星的吸附性能随氯化锌浓度和热解温度的增加呈先升后降趋势, 在氯化锌浓度为4.0mol·L-1、热解温度为500℃时有最优值; 随着热解时间的延长, 污泥基吸附剂对亚甲基蓝和环丙沙星的吸附性能分别在500℃热解70min和80min时有最优值. (3)污泥基吸附剂的最佳制备条件为 氯化锌4.0mol·L-1活化2h、500℃热解70min和80min、1.500mol·L-1盐酸酸洗; 以此制得的污泥基吸附剂对亚甲基蓝和环丙沙星的去除率分别为97.7%和96.4%, 平衡吸附量分别为97.9mg·g-1和3.9mg·g-1, 且污泥基吸附剂对亚甲基蓝和环丙沙星的吸附过程均符合准二级动力学方程.     

Pressurized liquid extraction and liquid chromatography–tandem mass spectrometry applied to determine iodinated X-ray contrast media in sewage sludge

Pressurized liquid extraction (PLE) has been successfully applied for the first time to the extraction of five iodinated X-ray contrast media from sludge. Once optimized all PLE parameters, the extract has been analyzed by liquid chromatography–tandem mass spectrometry, being the method developed sensible enough to reach limit of quantifications (LOQs) of 25 μg kg⁻¹ (d.w.). The developed method has been applied to the analysis of sludge from urban sewage treatment plants and although some compounds such as iopromide, diatrizoic acid and iopamidol have been identified, their concentrations have been lower than their LOQs.     

Bioremediation of Aged Petroleum Oil Contaminated Soil: From Laboratory Scale to Full Scale Application

Large quantity of aged petroleum oil contamination such as dehydrated oil sludge, generated in the disposal process of oil-containing sewage in Indonesia. This study aims to investigate the OSCS removal by mean of bioremediation technique. Results found that petrofilic consortia and biosurfactants addition increased the removal efficiency up to 46% and 85%, respectively. At full scale application, this technique succeed in removing of 46 g TPH per kg soil from 4 883 m³ of OSCS during 16 mo of treatment. These results suggest that petrofilic consortia and biosurfactants addition stimulate the biodegradation and overcome the limitation of OSCS degradation process.     

钢渣与污泥协同资源化研究进展

钢渣和污泥作为传统大宗固体废弃物,始终面临处理成本高、回收利用率低等问题,但其内部含有大量可利用物质,具有较高的资源化利用价值,现已成为国内外的研究热点。为了提高钢渣与污泥绿色、高效、协同资源化利用,综述了近年来国内外钢渣在建筑、道路、水处理、农业等领域资源化利用的研究进展,立足固废无害化、减量化,从钢渣和污泥的资源化进行分析与总结,指出不同研究方法的特点和优劣,为固废资源化利用提供参考。并基于我国发展现状对钢渣与污泥资源化利用的未来发展方向进行了展望,以期为固废处理行业的良性发展提供一定的理论支撑。     

Application of Natural Clinoptilolite for Ammonium Removal from Sludge Water

Sludge water (SW) arising from the dewatering of anaerobic digested sludge causes high back loads of ammonium, leading to high stress (inhibition of the activity of microorganisms by an oversupply of nitrogen compounds (substrate inhibition)) for wastewater treatment plants (WWTP). On the other hand, ammonium is a valuable resource to substitute ammonia from the energy intensive Haber-Bosch process for fertilizer production. Within this work, it was investigated to what extent and under which conditions Carpathian clinoptilolite powder (CCP 20) can be used to remove ammonium from SW and to recover it. Two different SW, originating from municipal WWTPs were investigated (SW1: c₀ = 967 mg/L NH₄-N, municipal wastewater; SW2: c₀ = 718–927 mg/L NH₄-N, large industrial wastewater share). The highest loading was achieved at 307 K with 16.1 mg/g (SW1) and 15.3 mg/g (SW2) at 295 K. Kinetic studies with different specific dosages (0.05 g_CLI/mg_NH4-N), temperatures (283–307 K) and pre-loaded CCP 20 (0–11.4 mg/g) were conducted. At a higher temperature a higher load was achieved. Already after 30 min contact time, regardless of the sludge water, a high load up to 7.15 mg/g at 307 K was reached, achieving equilibrium after 120 min. Pre-loaded sorbent could be further loaded with ammonium when it was recontacted with the SW.     

Identification and Quantification of Polycyclic Aromatic Hydrocarbons in Polyhydroxyalkanoates Produced from Mixed Microbial Cultures and Municipal Organic Wastes at Pilot Scale

Polyhydroxyalkanoates (PHAs) are well-known biodegradable plastics produced by various bacterial strains, whose major drawback is constituted by the high cost of their synthesis. Producing PHAs from mixed microbial cultures and employing organic wastes as a carbon source allows us to both reduce cost and valorize available renewable resources, such as food waste and sewage sludge. However, different types of pollutants, originally contained in organic matrices, could persist into the final product, thus compromising their safety. In this work, the exploitation of municipal wastes for PHA production is evaluated from the environmental and health safety aspect by determining the presence of polycyclic aromatic hydrocarbons (PAHs) in both commercial and waste-based PHA samples. Quantification of PAHs by gas chromatography-mass spectrometry on 24 PHA samples obtained in different conditions showed very low contamination levels, in the range of ppb to a few ppm. Moreover, the contaminant content seems to be dependent on the type of PHA stabilization and extraction, but independent from the type of feedstock. Commercial PHA derived from crops, selected for comparison, showed PAH content comparable to that detected in PHAs derived from organic fraction of municipal solid waste. Although there is no specific regulation on PAH maximum levels in PHAs, detected concentrations were consistently lower than threshold limit values set by regulation and guidelines for similar materials and/or applications. This suggests that the use of organic waste as substrate for PHA production is safe for both the human health and the environment.     

微波消解-ICP-MS测定电镀污泥中的重金属

采用微波消解系统对某电镀污泥进行消解,利用ICP-MS对污泥中的重金属进行测定。称取制备后样品,置于消解罐中充分反应后,赶酸、定容后利用电感耦合等离子体质谱法进行测定。电镀污泥中的铬为18845.2mg/kg、镉为10.3mg/kg、镍为5200.0mg/kg、铅为189.7mg/kg、铜为3271.7mg/kg、锌为49632.6mg/kg。测定结果表明所检测项目工作曲线线性关系好,相关系数r均大于0.999。铬加标回收率在91.6～97.7%之间、镉加标回收率在92.0～97.0%之间、镍加标回收率在95.1～98.0%之间、铅加标回收率在94.3～95.2%之间、铜加标回收率在97.1～102%之间、锌加标回收率在96.3～98.7%之间,均满足相关测定要求。计算的潜在生态危害系数、潜在生态危害指数结果表明,电镀污泥中的铬、镉、铅、铜、锌为轻微生态危害,镍为强生态危害;潜在生态危害指数RI计算值为216.69,属于中等生态危害。     

电镀法测表面应力

电镀法是在被测物表面镀铜或镀镍,在交变应力作用下,利用镀层内的组织变化来测定表面弹性应力应变的方法。本文简述电镀法原理,讨论其在实物交变应力及高温应力测量中的应用。     

Study on the changes of ultrasonic parameters over supercritical Ni-Co electroplating process

This work discusses the influence of changes to ultrasound (US) parameters over the nickel cobalt (Ni-Co) metal thin film properties produced by supercritical CO₂ (SC-CO₂) electroplating. Additionally, Ni-Co films were produced by conventional electroplating and silent SC-CO₂ and compared against each other.The discussion on metal thin film properties revolves around variations to the bath type ultrasonic power (15 W and 20 W) and frequency (42 k Hz and 72 kHz) during experiments. The properties provided by the three electroplating processes and analyzed include: grain sizes, film elemental content analyses, surface microstructures, film hardness, corrosion resistance, surface roughness, crystalline structure and preferential growth, etc. From the results it was clear that quality of films produced by US-SC-CO₂ was improved compared to that of films produced by silent SC-CO₂, which itself was better than those produced by conventional electroplating. However, when US power was varied we observed a decline in the mechanical properties of the produced films.The combination of ultrasonic agitation with SC-CO₂ allows for improved mechanical properties such as: lower surface roughness, finer grain size and surface morphologies, increased corrosion resistance and film hardness. The ultrasound agitation applied to SC-CO₂ electroplating enhanced the formation of alloyed metal as ultrasonic agitation increased the electrolyte flowability during electroplating process resulting in increased mass transfer while at the same time achieving a surface cleaning effect which removed metal ions with poor adhesion and other unwanted particles. Moreover, application of ultrasonic agitation avoids the use of surfactants so only changes to the physical phenomena and no changes to the chemical composition of the deposited thin films were observed, meaning less pollution to the electrolyte and higher purity of the deposited films.The US-SC-CO₂ electroplating method described in this work effectively enhanced the mechanical properties of the deposited thin films compared to those produced by both silent SC-CO₂ and conventional electroplating processes.     

Synthesis of nanocomposites from cationic polyacrylamide and modified carbon black: Application as flocculants for oily sludge suspension

Carbon black was modified using various liquid‐phase oxidation methods (modified carbon black = m‐CB, m = (1, 2, 3): 1, sulfuric acid/potassium permanganate method; 2, nitric acid method; 3, hydrogen peroxide method). With acetone–ethylene glycol as initiator, dimethyldiallylammonium chloride (DMDAAC) and acrylamide (AM) as monomer, cationic polyacrylamide (CPAM) was prepared by UV excitation of the monomer. The m‐CB/CPAM nanocomposites were synthesized using a hydrothermal method. The factors that affected the molecular weight of CPAM were investigated, including the total monomer concentration, the dosage of the complex initiator, the mass ratio of m_AM:m_DMDAAC and the UV irradiation time. The chemical structures and morphologies of the samples were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental composition, X‐ray diffraction and scanning electron microscopy. 1‐CB/CPAM was utilized to flocculate oil sludge suspension, and the effects of 1‐CB quality, 1‐CB/CPAM dosage, temperature and pH value on the flocculation performance of 1‐CB/CPAM were investigated. The flocculation mechanism of 1‐CB/CPAM was also analyzed. The results show that 1‐CB/CPAM has an outstanding flocculation effect, and it flocculates oil sludge particles by adsorption bridging and charge neutralization in acidic and alkaline conditions.