Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA,2017年35(10):1064-1071 ISSN：0734-242X
[Li, Qibin; Liu, Hong; Jiang, Guobin; Liu, Dan; Chen, Weiming; Ye, Zhicheng] Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, China;[Li, Qibin] Laboratory of Treatment for Special Wastewater of Sichuan Province Higher Education System, China
[Li, Qibin] Southwest Jiaotong Univ, Fac Geosci & Environm Engn, 111,North Sect 1,2nd Ring Rd, Chengdu 610031, Sichuan, Peoples R China.
This paper develops an indicator system consisting of three criterion layers and 13 specific indicators. This indicator system can be used for water resources utilizability evaluation during subway construction in water-rich weakly consolidated formation. The weight of each index is determined by using Delphi and G1 methods, and the assessment criteria is constructed according to related standards, specifications and the practice of Chengdu subway construction. Jiulidilukou station of Chengdu Metro Line 7 is selected as a case study, and the results show that its water utilizability during the construction is excellent, which indicating that the water pumped from aquifer should be reused after some proper measures instead of wasting of water resources.
We developed a semi-aerobic aged refuse biofilter (SAARB) for leachate treatment and examined its advantages and disadvantages compared to previous aged refuse biofilters (ARBs). To assess its treatment capability, decontamination mechanisms and optimal performance parameters, a single-period experiment and L(9)(3(4)) orthogonal array design experiments were conducted on artificial leachate. The SAARB markedly enhanced the treatment capability and removal efficiency of organic matter and nitrogen pollutants due to the alternating aerobic-anoxic-anaerobic zones in situ. The reduction in chemical oxygen demand (COD), ammonia nitrogen (NH(4)(+)-N) and total nitrogen (TN) exceeded 98%, 94%, and 80%, respectively. After the leachate was distributed onto the SAARB surface, the effluent velocity decreased as a logarithmic function, and there was a concomitant reduction in leachate effluent volume. Based on the capacity for removal of COD. NH(4)(+)-N, and TN, the effective height of aged refuse in a SAARB was enough to be 900 mm. An excellent treatment efficiency could be achieved at 20-35 degrees C, with a leachate distribution time of 1 h once every period of 2-3 days, hydraulic loading of 11-30 L/(m(3) day), and COD loading of 550-1200 g/(m(3) day). This new SAARB system demonstrates superior efficacy for biofilter compared to other ARB systems, especially for nitrogen removal from leachate. (C) 2011 Elsevier Ltd. All rights reserved.
A removing mechanism for organics and nitrogen using a semi-aerobic aged refuse biofilter (SAARB) was evaluated based on the space structure, the aged refuse conformation and characteristics, as well as the degradation theories of organic matter and nitrogen-based substances, which could provide a fundamental theory to more effectively treat organic matter and nitrogen-based pollutants in leachate. The experimental results indicated that the average removal rate of chemical oxygen demand and total nitrogen reached 96.61 and 95.46%, respectively. The aerobic-anoxic-anaerobic zones appeared alternately in both the space structure and the granule conformation inside of the SAARB, which promoted various physical, chemical and biological reactions. Most biodegradable organic matter was converted to CO2 and CH4. The average CO2 release rate was 1.567 L/(h m(2)) in the winter and 1.467 L/(h m(2)) in the summer during a single-period experiment. The average CH4 release rate was 0.303 L/(h m(2)) in the summer; however, it could not be detected in the winter. Moreover, the nitrogen-based pollutants were mostly converted to N-2 and N2O through denitrification. Some of the refractory organic matter and nitrogen-based pollutants were likely adsorbed by the aged refuse and biodegraded more slowly. The adsorption rate of biologically degradable matter (BDM) was 0.624 g/(kg d) during the first 40 weeks and the largest absorbance of total nitrogen (TN) was about 7.0 g/kg during this experiment. Therefore, the SAARB can maintain stable and highly efficient environment for removing organic matter and nitrogen-based pollutants. (c) 2012 Elsevier Ltd. All rights reserved.
[Liu, Jie; Liu, Dan] Department of Environmental Science and Engineering, Southwest JiaoTong University, Chengdu Sichuan Province, China;[Liu, Min; He, Yanfeng] State Key Laboratory of Development Environment, Beihang University, Beijing, China
8th World Congress on Intelligent Control and Automation (WCICA)
According to the characteristics of anaerobic, aerobic and semi-aerobic bioreactor landfill, combined with the status of rural garbage disposal. Indoor simulation comparison tests were carried out between anaerobic (R3-I) - semi-aerobic (R3-II) united bioreactor and anaerobic (R1), semi-aerobic (R2) bioreactor to handle Rural garbage solid indicators. The results shows that the cumulative settlement number of anaerobic unit (R1, R3-I) has logarithm relation versus time, while the cumulative settlement number of semi-aerobic unit (R2, R3-II) is linear versus time. The BDM of garbage in semi-aerobic unit (R2, R3-II) declined faster than that of anaerobic unit (R1, R3-I). The landfill of anaerobic - semi-aerobic united bioreactor can facilitate the degradation of nitrogen substances, and is advantageous than that anaerobic bioreactor landfill and semi-aerobic bioreactor landfill runs separately. During each test, garbage column aqueous rates maintained at a high level and changed slightly.
[Liu Wei] Southwest Jiaotong Univ, Fac Geosci & Environm Engn, Chengdu 610031, Peoples R China.
2nd International Conference on Energy, Environment and Sustainable Development (EESD 2012)
OCT 12-14, 2012
Jilin, PEOPLES R CHINA
[Liu Wei] Southwest Jiaotong Univ, Fac Geosci & Environm Engn, Chengdu 610031, Peoples R China.
Advanced Materials Research
Passive solar house;trombe wall;temperature
This paper presents evidence from the recent study of an effect analysis of a passive solar house in Tibet. A passive solar house in Tibet is first introduced. The passive solar house was divided into two parts by trombe wall, by measuring the temperature of two different parts, the result showed that the temperature in heat preserve room and bath room appeared different changes but had the similar trend with outside temperature. In the test conditions, the daily mean temperature of these two different places ranged from 12.77 degrees C similar to 14.60 degrees C to 11.21 degrees G similar to 13.95 degrees C respectively, which reached our requirement. The results indicated that the solar house can improve the thermal environment for the resident.
The bioreactor, filled with aged refuse, was used to remove different nitrogen compounds from refuse leachate, by means of injection in the laboratory. The research is focused on the efficiency, main influencing factors and biological mechanism of nitrogen removed from the leachate. It is indicated from the findings that in case of injection period of 12h, injection quantity of 0.5L, and CODcr concentration of 6000mg/L in influent, the NH3-N concentration in leachate is reduced from 195-2000mg/L to 5-20mg/L, with a removal efficiency of over 93%, meanwhile, that TN removed up 82%. The nitrogen removal is influenced mainly by such factors as BOD5/TN of influent, oxidation-reduction conditions of the bioreactor, operation temperature of the bioreactor and pH of influent. When the BOD5/TN is higher than 1-3, the Eh more than 100mV, the temperature approximate to 30 degrees C, and the pH to 7, the bioreactor is able to achieve a satisfied nitrogen removal efficiency. A biological mechanism of nitrogen removal is proved to mainly be a joint action of nitrosification, nitrification, aerobic denitrification and anaerobic denitrification. Based on the inference of biofilm on the aged refuse particles, processes of nitrosification and nitrification are mainly accomplished on surface of the particles, while processes of aerobic denitrification and anaerobic denitrification mainly accomplished in the aerobic layer and the anaerobic layer of the biofilm, respectively. The research gives guidance in achievement of economical and effective nitrogen removal of leachate.
Two different leachates of Chang 'an landfill in Chendu were collected as the object of study. The components of organic pollutants in leachates were detected by combined GCMS technique based on the general water quality analysis. Test results of study are as the follows: the type and nature of organic pollutant effect directly on leachate biodegradability. In high biodegradability (BOD5/CODCr = 0.3 similar to 0.4) leachte, the detected organic pollutant are mainly composed of carboxylic acids and their content accounts for about 90%. While in low biodegradability (BOD5/CODCr < 0.15) leachte, the detected organic pollutant are mainly composed of alkanes and their content accounts for about 50%. The research provides a new idea and pathway for the treatment and pollution control of leachate from municipal solid waste landfills. The article presents a optimizing principle of integrated physic-chemical and biological treatment technologies in treating mixed leachate.
根据厌氧、好氧以及准好氧生物反应器填埋场的各自特点,结合我国农村生活垃圾处理现状,开展了厌氧(R3I)-准好氧(R3-II)联合生物反应器与厌氧(R1) 、准好氧(R2)生物反应器的室内模拟对比试验。结果表明,厌氧单元(R1、R3-I)累积沉降量与时间成对数关系,而准好氧单元(R2、R3-II)的累积沉降量与时间成线性关系;联合生物反应器中的厌氧单元未出现酸累积现象;联合反应器中各单元对COD的降解趋势与准好氧生物反应器高度一致,在第350天,R3-II渗滤液COD降至7.67 g /L;联合生物反应器对以UV_(254)表征的有机物的去除效果优于厌氧生物反应器和准好氧生物反应器;厌氧-准好氧联合型生物反应器能够有效抑制氨氮的积累,使体系内的氨氮处于一个相对稳定的水平。