负载型TiO2催化剂对提高老龄化垃圾渗滤液可生化性处理效果的研究

本文针对在不同条件下的光化学氧化处理高浓度垃圾渗滤液，进行了改善其可生化性与提高NH3～N去除率的研究。在负载型TiO2催化剂催化下BOD5／CODCr，值从0、064提高到0，228，超过了0.1的可生化性要求。二氧化钛催化剂对NH3-N去除效果明显，15minNH3-N去除率可达80.19％。     

高浓度氨氮渗滤液脱氦方式的比较及选择

氨氮浓度高是垃圾渗滤液的水质特征之一,目前对于高浓度氨氮废水的处理方法主要有硝化—反硝化、氨吹脱法、化学沉淀法以及新型生物脱氮技术。基于工程实例,对国内外已有的去除垃圾渗滤液高浓度氨氮的方法进行了阐述和对比,并对渗滤液处理厂脱氮方式的选择提出了建议。     

Determination of physical and chemical properties of waste tyres in usage/storage areas

Used tyres interact with soil, water and the atmosphere during temporary or permanent storage and also when used as additive or paving materials in landscapes, asphalt, concrete and for coastal protection. Various organic and inorganic compounds can penetrate into the environment from used tyres at various rates dependent on climatic and soil conditions. In this study, laboratory leaching batch experiments were conducted to determine the heavy metals and other constituents that could possibly penetrate into the leachate created during tyre usage/storage. The results obtained in this study showed that tyres were dissolved due to their usage and the climatic and environmental conditions thus leading to soil and groundwater pollution in their usage/reuse/storage/disposal areas. Zinc concentrations were the highest among the heavy metals measured in the simulated leachate. The average weight loss for all tyre samples was calculated as 3.6‰.     

Bench Scale Studies for Pretreatment of Sanitary Landfill Leachate with Moringa Oleifera Seeds Extract

A laboratory study using a bench scale model of two unit operations involved processes of coagulation (using Moringa oleifera seeds as a natural coagulant) and flocculation-sedimentation have been adopted to treat the leachate from Air Hitam Sanitary Landfill at Puchong in Malaysia. The results of this study has shown, that M. oleifera has a potential for the removal of heavy metals from the leachate, and may be used as a pre-treatment stage for biological treatment to eliminate a portion of the toxic heavy metals, which limit the activity of micro-organisms in the leachate.     

Transformation of phthalic acid diesters in an anaerobic/anoxic/oxic leachate treatment process

Transformations of di-n-butyl phthalate(DBP) and di(2-ethylhexyl) phthalate(DEHP) have been investigated in anaerobic/anoxic/oxic(A/A/O) leachate treatment processes. Although the DBP removal processes are different when the DBP initial concentration is different, the overall system DBP removal efficiencies are high(N 94%).DEHP is much more difficult to remove than DBP. The removal efficiency of DEHP is approximately 75%–78%.The results of mass balance calculations indicate that approximately 33.7%–50.7% of the DBP is degraded by the activated sludge, 48.9%–64.9% accumulates in the system, and 0.4%–1.4% is contained in the final effluent. Approximately 15.0%–19.0% of the DEHP is degraded by activated microcosms, 75.8%–79.0% accumulates in the system, and 5.2%–6.0% is contained in the final effluent. Biodegradation and adsorption to the activated sludge are the main mechanisms for DBP removal and adsorption to the activated sludge is the main mechanism for DEHP removal. The different removal mechanisms of the two PAEs may be related to their different molecular structures. However, PAEs are not really removed when they adsorb onto the sludge. Therefore, methods for decreasing PAEs adsorption and increasing the biodegradation efficiencies of the leachate treatment processes should be further investigated.     

Investigations on Ozone Contacting by Ceramic Membranes

Ozone transfer was investigated using various oxide ceramic membranes and different process parameters. The ozone mass transfer per contactor volume through hydrophilic membranes was in the same order of magnitude as conventional bubble contacting. The pressure differential between the gaseous and aqueous phase as well as the membrane material's microstructure was found to widely determine the transfer rate. A hydrophobic coating of the membrane surface led to a considerable increase in transfer. Bubble free ozone contacting with porous ceramic is a possible approach for the ozonation of problematic wastewaters susceptible of excessive foam formation.     

Estrogenic activity of fractionate landfill leacahte

Dissolved organic matter (DOM) in leachate samples collected at Laogang Sanitary Landfill in Shanghai, China were fractionated using size exclusion chromatography and were characterized using estrogen receptor-α competitor screening assay as toxicity activity index. The estrogen activity of leachate was determined mainly by the hydrophobic acid DOM with moderate MW (3000-14,000 Da) and low MW (< 630 Da) and with high aromaticity and fluorophores of possibly pyrenyl characteristics. Landfilling for up to seven years or oxic storage for one month degraded a few of these estrogens. Aerobic SBR treatments effectively degraded the hydrophobic estrogens, but rarely degraded the hydrophilic estrogens.     

“Fenton-MBR生物滤池”工艺的设计与应用

广州某垃圾填埋场目前每天有10 m3的垃圾渗滤液排放,为减少环境污染,防止发生环境污染纠纷,保护周边水环境,要求对渗滤液进行处理。项目采用"预处理+生物处理+深度处理"的处理工艺,其中"深度处理"采用"Fenton-MBR生物滤池"工艺,经该系统处理后废水水质稳定达标排放。     

Ceramic Raschig Rings—Improving Removal of Organic Compounds from Landfill Leachate by Perozone (O3/H2O2)

For improving the treatment of landfill leachate by combination O₃/H₂O₂, ceramic Raschig rings (CRR) with different surface areas were added to enhance mass transfer of ozone into liquid phase. To determine optimal conditions of reaction, pH and reaction time was also studied. The optimal pH range of 8–9, optimal reaction time of 80 min was identified in this research. CRR contribute to the significant improvement of efficiency of landfill leachate treatment by O₃/H₂O₂ systems. With added CRR of 728 m²/m³ surface area, color, COD and TOC removal was increased in comparison with experiment without CRR is 8%, 14%, and 9%, respectively. In this condition, the ozone utilization efficiency was also higher than that of experiment without CRR. Content of O₃ was also identified uses 3.441 kg O₃/kg COD.     

Post-Treatment of Composting Leachate by Ozonation

The post-treatment of composting leachate via an ozonation process in laboratory scale was studied in batch mode. According to the experiments, the COD removal was 47% after 30 min of ozonation via 0.4 g/h ozone (equivalent to 2.8 mg O₃/mg COD removed) at pH 9. In this circumstance, the removal of color and turbidity was also 86% and 89%, respectively. Increasing the ozone mass flow rate higher than 0.4 g/h had no considerable effect on the process variables. However, increasing the reaction time had a significant effect on both the removal of color and on COD of the leachate. Experimental data indicated that complete removal of color and 51% removal of COD were achieved after about 40 min of ozonation via 0.4 g/h ozone (equivalent to 3.3 mg O₃/mg COD removed). The ozone consumption rate increased as the reaction progressed and reached 4.1 mg O₃/mg COD removed after 60 min.