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1.
Experimental Study on Improving the Biochemical Character of Late Leachate by Electrochemical Method
Electrolytic oxidation can remarkably improve the biochemical character of late leachate under the condition of aeration. Test result indicates that the biochemical character of late leachate can be improved from 0.11 to more than 0.30 under the condition when the electrical density is 15mA/cm^2 and the electrolytic period 6.5 hours. 相似文献
2.
The current status of leachate treatment in garbage landfills and its treatment difficulties were elaborated and summarized. Based on the advantages and disadvantages of various landfill leachate treatment technologies, a multi stage treatment composed of pretreatment, bio treatment and deep treatment was suggested as an ideal treatment. A new way to treat landfill leachate was presented. It combines electrochemical and oxidation ditches with sand filtration. The advantages of the new technique were also analyzed. 相似文献
3.
Gas pressure distribution in landfills is of great importance to control hazards and improve recovery of landfill gas. An one-dimensional steady-state model and its solving approach are presented for gas pressure distribution in layered waste landfills. The model can be used to investigate the gas pressure distribution of the landfill with horizontal gas collection layers having specified pressure or flux. The influences of layered properties, horizontal permeable layer under final cover and horizontal gas collection layers and bottom leachate drainage systems dually serving as gas collection layers on gas pressure distribution are investigated. The results of parameter analyses using the presented model show that the assumption that homogenizations of gas generation rate and gas permeability through a landfill considerably overestimate gas pressure in landfill; horizontal permeable layer under final cover and horizontal gas collection layers can effectively reduce gas pressure in landfills; the bottom leachate drainage systems dually serving as gas collection layers can significantly reduce the gas pressure in the lower portion of landfills. The presented model provides a useful tool in the designing of landfill gas collection systems, such as, the positions and spacing of horizontal gas collection layers and pump section. 相似文献
4.
Rubbish of landfill is the resource put down at the incorrect place. In case of taking unfit measure, there will be not only the waste of available resource, but also leading to secondary pollution and losing the initial meaning of sanitary landfill. This paper discusses three usually occurred secondary pollutions in sanitary landfill,namely the water pollution,air pollution and soil pollution. Then it gives a series of advices,measures and reclamation of solid wastes. It pays more attention to the method of preventing leachate leaklng,the design and material for the impervious layer and the leachate collecting and so on. Then it introduces the technology of rubbish disposing and its new tendency in the future. 相似文献
5.
By means of heat conduction model of the cathode of aluminum electrolytic tank,the gas baking startup technology for electrolytic tank is investigated numerically. Under different baking processes, the change of heating speed, temperature difference in the cathode and heating load vs. time are studied.The baking time needed and fuel consumption under different baking processes are discusses, and the characteristics of baking processes are compured each other. The result reveal the best process to startup electrolytic tank; it provides theoretical reference to work out proper baking process for gas baking startup technology for aluminum electrolytic bath. 相似文献
6.
The paper analyses the factors affecting leachate generation for landfill,and discusses the methods of calculation for leachate generation and indicates the effective ways to control leachate pollution on environment. 相似文献
7.
This paper focuses on the measures of rainwater and sewage shunting in Chongqing Changshengqiao sanitary landfill. The catchment area of this landfill is totally about 331700 square meters. If the rainwater blends with the sewage, the processing load of the leachate will increase greatly. Thus, the measures of rainwater and sewage shunting must be taken during solid waste filling. In this paper, the authors firstly analyze the measures of rainwater collection and drainage and establish the guideline of pumping assisted by draining. Furthermore, according to the practical situation of landfill, a detailed plan is set down for rainwater and sewage shunting. The effect is quite evident after implementation of the plan for half a year. The processing load of the leachate has been reduced largely. It is proven that the shunting measures are feasible. 相似文献
8.
为了有效降低垃圾渗滤液中高浓度的氨氮和有机污染物,以便降低后期生化处理的污染负荷,采用石灰混凝+吹脱+CO2曝气联合法对垃圾渗滤液进行预处理,通过单因素实验研究CaO投加量、曝气时间、反应温度及气液比等因素对渗滤液中氨氮、COD以及UV254的去除效果的影响;通过正交实验研究综合处理效果最好的反应条件,并在正交实验后进行CO2曝气,以期降低实验后较高的pH和钙离子浓度。结果表明：氨氮去除率与各单因素呈正相关关系,COD及UV254的去除率与CaO投加量相关性较大。在正交试验得出的最佳混凝吹脱条件下,氨氮、COD、UV254的去除率分别能达到98.8%、60.2%、68.7%。进一步CO2曝气后,垃圾渗滤液pH由12.1降至6.8,钙离子浓度降低70.3%,COD去除率可达65.7%。 相似文献
9.
It is difficult to treat landfill leachate in China.Traditional biologic method and physical method always have high expenses,or cann''t reach the discharge standards.The authors use a new biologic method to treat landfill leachate,which is the Wood_microbial System from Japan.The system to be digested by 3 aeration tanks and 1 reaction tank.The comparison combine processed wool_dust broken pieces with the certain grain degree size were throw in the tanks.Dirty and organic matter are in the digest tanks through the aeration reaction and aneration reaction repeatedly.In this experiment the speed of wastewater discharge and oxygen supply has been changed, and the change of biologic system and the effect of pollutant are removed. The optimal treatment condition can be found.The experiment shows that the system has a good result,special for nitrogenous.The BOD is average to do away with the rate to amount to 90%,almost reach the second class or third class for leachate standard.But BOD loading should be not beyond 4 kg/(m 3.d),othrwise,the system will not operate in normally. 相似文献
10.
电解铝厂周边农作物氟污染评价 总被引：2，自引：0，他引：2
为了解电解铝厂氟污染对周边农作物的影响,通过采用氟离子选择电极法,对凯里某电解铝厂周边农作物的氟含量及污染程度进行研究。结果表明：铝厂周边农作物中氟含量最高为163.33 mg/kg,最低为16.73 mg/kg,平均含量为51.09 mg/kg,都已超过国家标准规定的农作物中氟污染物最大容许含量,农作物受到了较为严重的氟污染。不同农作物对氟的吸收、积累能力不同;农作物不同器官对氟的积累不同,对氟的吸收主要集中于叶片。铝厂周边不同区域的农作物都受到严重程度的氟污染,主要与铝厂的距离有关,距离铝厂越近,农作物受到氟污染越严重。 相似文献
11.
为了研究PRB技术修复垃圾渗滤液污染地下水的可能性,筛选最佳反应介质及其配比,为城市垃圾渗滤液污染地下水的治理提供参考,选择零价铁粉、膨润土、沸石、活性碳、炉渣5种反应介质,研究其对垃圾渗滤液污染地下水的治理效果。结果表明：5种反应介质单独作用下,活性炭对地下水中的COD去除效果最好,去除率达到76.0%,沸石对COD去除效果最差,去除率仅为45.0%,但沸石对地下水中NH3的去除效果最好,去除率为70.8%,零价铁对NH3的去除效果最差,去除率为42.3%;选择零价铁、活性炭、沸石3种介质按照不同配比继续试验,得出对COD的去除效果以零价铁：活性炭：沸石= 2:2:1的比例最好,其次是1:2:2和2:1:2,对NH3的去除效果以零价铁：活性炭：沸石=1:2:2的比例最好,其次是2:1:2和2:2:1。 相似文献
12.
Cavitating water jets were used to degrade complicated organic compounds sampled from landfill leachate from a sanitary landfill in Chongqing, P. R. China. The law of chemical oxygen demand (COD) and the impact of factors such as pumping pressure, confining pressure, cavitating time and pH were evaluated in the experiment. We concluded that a cavitating water jet can degrade complicated organic compounds. Cavitating water jets therefore can improve biological oxygen demand (BOD)5/COD. The optimal cavitating condition was also obtained: at a pH 9.0, confining pressure 0.6MPa, cavitating time 90mins and pumping pressure 10MPa,the COD, BOD5 and BOD5/COD increase to 124.8%, 293.3% and 52.44% respectively. Chromaticity decreases while SS increase to 191.5%. These changes create good conditions for subsequent treatment. 相似文献
13.
生物质炭对垃圾渗滤液中氨氮去除效果的研究 总被引：4，自引：2，他引：2
为了寻找经济、有效的氨氮吸附材料,为物化处理技术在垃圾渗滤液上的运用提供一些实际参考的选择,以生物质炭（木炭）作为吸附材料进行吸附试验,研究木炭投加量、渗滤液初始pH值、吸附时间、氨氮浓度4个因数变化的条件下,木炭对垃圾渗滤液中氨氮的去除率及其吸附动力学特征。结果表明：随着木炭用量的增加,木炭对氨氮的吸附量逐渐增大,木炭投加量为80~160 g/L时,渗滤液中氨氮的去除率达34.27%~39.41%。在最佳pH 10和最佳吸附时间240 min条件下,木炭对渗滤液中氨氮的去除率分别为24.21%、16.91%。木炭对垃圾渗滤液的氨氮有一定的去除效果,其吸附动力学特征符合伪二级动力学方程和颗粒内扩散方程。 相似文献
14.
超声波对垃圾渗滤液COD和氨氮去除的研究 总被引：2，自引：0，他引：2
摘要：试验采用超声波作用去除垃圾渗滤液中COD和氨氮。通过正交设计,探讨了活性炭用量、pH值、超声波功率、辐照时间、曝气时间5个因素对COD和氨氮去除率的影响。结果表明在活性炭用量1.0g,pH为9,超声波强度为360W,辐照时间为6min,曝气时间为6min时处理COD和氨氮综合去除效果最好,COD去除率为63.7%,氨氮去除率为80.24%。 相似文献
15.
工业污水和生活污水排放量日益增多,污水处理厂污泥产量日趋加大,污泥填埋关键技术问题已成为当今环境工程以及环境岩土工程的热点问题之一。污泥和垃圾混合填埋在其他国家已得到应用,但由于目前中国关于污泥及其城市生活垃圾混合样的基础性室内试验成果不多,对污泥与城市垃圾混合样的工程力学特性及其混合填埋的适宜比例等不甚了解,从而导致中国污泥垃圾混合填埋工程事故频繁发生。对不同配比的污泥与城市生活垃圾混合样进行了固结压缩实验、三轴固结不排水实验、无侧限抗压强度实验,得出污泥与城市生活垃圾混合样的工程力学特性;同时,用ANSYS数值模拟方法,对不同配合比的污泥城市生活垃圾混合填埋边坡的稳定性进行分析,从而对污泥与城市生活垃圾混合填埋的适宜配合比及其稳定安全问题提出理论支撑。 相似文献
16.
固化污泥是一种新型填埋场底部防渗阻滞材料，为论证其防渗阻滞作用的有效性，需进行典型污染物的穿透试验，但由于固化污泥渗透性很低，采用常规土柱试验很难得到污染物透过其迁移时的相关参数。为解决该问题，用柔性壁渗透试验代替传统土柱试验。渗滤液中污染成分较多，取含量较高且较易穿透的污染物即氟离子作为典型污染物，首先进行穿透试验获得迁移参数，然后结合二维有限元法研究分析其在防渗阻滞层及周边岩土环境中60 a内的运动迁移范围、浓度分布情况，并对比分析未设防渗阻滞层的情况。研究表明，在填埋场底部设置固化污泥防渗层对于以氟为代表的阴性污染物有较好的延迟阻滞作用。由于阳性污染物的穿透能力较阴性污染物弱，因而固化污泥防渗层对重金属等阳性污染物也应具有较强的阻滞作用，从而能进一步延迟填埋场渗滤液对周边环境的污染。 相似文献
17.
In this paper, the landfill gas generation process was investigated by a landfill lysimeter of municipal solid waste (MSW) co-disposed with wastewater sludge. The experimental results show that the wastewater sludge played a role of inoculation in MSW degradation process and accelerated organic waste decomposition. Compared with the MSW landfill alone, the landfill gas generation rate of MSW co-disposed with sludge was higher by about 30%. The average CH 4 content in landfill gas reached 64%, which was much higher than in case of MSW landfill alone and useful for landfill gas utilization. It is also proved that co-disposal of sludge with MSW is a good choice for beneficial use of sludge. 相似文献
18.
In order to solve desiccation cracks of conventional compacted clay cover system in arid and semi arid areas, three alternative evapotranspiration (ET) covers were proposed.One alternative option configuration consisted of 1m vegetation soil layer and 1m barrier soil layer, while two additional alternatives contained biointrusion barriers layer placed at different depths within the structural profile.Considering precipitation and evapotranspiration, a one dimensional moisture transport model through multilayer unsaturated soil was developed.By the case study of four covering systems under precipitation and evapotranspiration intensity of Dalian city at 1976, it was shown that the compacted clay layer of the traditional landfill cover could not get effective moisture charge.ET cover act as a reservoir during precipitation events and subsequently returned it to atmosphere as evapotranspiration.The biointrusion barriers layer located in the second ET cover design would restrict animal movement and play a key role in drainage.Consequently, these results would be used to assist in decisions making of the landfill cover system in semi arid areas. 相似文献
19.
Zhi-Hui LIU Gao-Feng PAN Wen CHEN Ming-Guang QIN Cou-Gui CAO Chang-Long CHANG Ming ZHAN 《作物学报》1962,46(12):1945-1957
Maize-late rice cropping (M-R) is considered to coordinate the production of food and feed crop. In recent years, M-R has begun to develop in the middle reaches of the Yangtze River. However, technologies have not been systematically studied and improved for its higher yield and higher resources use efficiency. Especially, a reasonable collocation of varieties between maize and late rice seasons is an important basis to realize the yield potential of M-R, and still is under evaluation. In this study, different maize and late rice varieties were selected and collocated to different M-R modes. Their yield performance and use efficiency of resources were detected in different regions of Hubei province in 2015 and 2017. The results showed that under different heat conditions, the varieties collocation modes had significant effects on the annual yield of M-R and the production efficiency of resources. The modes of medium maturity maize-late indica rice cropping had obviously higher annual yield and resource production efficiency under higher accumulated temperature (GDD≥10°C); on the contrary, the annual yield and resource production efficiency of the modes of early maturity maize-late indica rice cropping were higher under lower GDD≥10°C. The utilization percentage of the annual effective GDD≥10°C of each varieties combination mode could reach 95.6%-100.0%, and the distribution ratio of GDD≥10°c between previous and subsequent season (TR) had a significant non-linear relationship with the relative annual yield of M-R. When the utilization percentage of GDD≥10°C was 97.0%-98.5% and TR was 1.06-1.08, M-R could obtain highest annual yield. Therefore, suitable varieties of maize and late rice could be selected according to the local heat resource and reasonable TR. In summary, high-yield maize varieties with a growth period of 125 days and late rice varieties with a growth period of 140 days should be selected for the southern regions with higher GDD≥10°C, while high-yield maize varieties with a growth period of 120 days and late rice varieties with a growth period of 130 days should be selected for the middle and northern regions with relatively lower GDD≥10°C in Hubei province. 相似文献
20.
不同施肥和耕作方式下强化栽培水稻的生长与氮素利用 总被引：4，自引：1，他引：3
研究了不同施肥和耕作方式下强化栽培水稻的生长及氮素利用。结果表明,免耕条件下以尿素＋猪粪强化栽培水稻的产量最高,而常耕条件下以单施尿素常规栽培水稻的产量最高,但各处理的产量差异并不显著。无论是免耕还是常耕条件下,单施尿素常规栽培水稻比单施猪粪强化栽培水稻植株积累更多的氮素量,但其氮素稻谷生产效率、氮素收获指数下降。两种耕作方式比较,免耕条件下水稻的氮素运转效率、氮素农艺效率显著高于常耕,但常耕条件下的氮素回收效率比免耕的高127.95%,差异显著。 相似文献