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111.
稠油污水处理系统改造与絮凝剂筛选试验研究 总被引:2,自引:1,他引:2
河南油田井楼稠油联合站含油污水中的污油和悬浮物含量较高,超过150mg/L。为此,对该处理系统进行了改造,并对絮凝剂的筛选进行了试验。结果表明:无机絮凝剂与有机絮凝剂联合作用,可对污水中所含有的污油和有机物杂质的悬浮物产生很好的絮凝沉降效果。加药浓度、加药顺序及沉降时间均对絮凝沉降效果有一定的影响。改造后的污水处理系统实现了污水达标回注,降低了无效回注费用。同时还回收了污油,降低了药剂成本,产生了十分明显的经济效益,每年节约成本约500万元。 相似文献
112.
E. Conrad Lamon Song S. Qian Daniel D. Richter 《Journal of the American Water Resources Association》2004,40(5):1219-1229
ABSTRACT: Dynamic linear models (DLM) and seasonal trend decomposition (STL) using local regression, or LOESS, were used to analyze the 50‐year time series of suspended sediment concentrations for the Yadkin River, measured at the U.S. Geological Survey station at Yadkin College, North Carolina. A DLM with constant trend, seasonality, and a log10 streamflow regressor provided the best model to predict monthly mean log10 suspended sediment concentrations, based on the forecast log likelihood. Using DLM, there was evidence (odds approximately 69:1) that the log10 streamflow versus log10 suspended sediment concentration relationship has changed, with an approximate 20 percent increase in the log10 streamflow coefficient over the period 1981 to 1996. However, sediment concentrations in the Yadkin River have decreased during the decade of the 1990s, which has been accompanied by a concomitant increase in streamflow variability. Although STL has been shown to be a versatile trend analysis technique, DLM is shown to be more suitable for discovery and inference of structural changes (trends) in the model coefficient describing the relationship between flow and sediment concentration. 相似文献
113.
基于可接受安全间距的单车道交通流模拟模型 总被引:1,自引:1,他引:1
交通流微观模拟是采用计算机对交通流进行描述及分析的方法。尤其对于复杂的交通流而言,微观模拟具有明显的优势,然而模拟的准确与否,关键在于模型的建立。笔者即是在研究我国单车道交通流特点的基础上,借鉴车道变换理论,基于驾驶员可接受的交通安全间距,分析安全变换车道的各间距之间的关系,阐述了有超车的单车道交通流模拟模型的建立方法 相似文献
114.
Chinese brake fern (Pteris vittata L.) is a hyperaccumulator of arsenic (As) that grows naturally on soils in the southern United States. It is reasonable to expect that mycorrhizal symbiosis may be involved in As uptake by this fern. This is because arbuscular mycorrhizal (AM) fungi have a well-documented role in increasing plant phosphorus (P) uptake, P and As have similar chemical properties, and ferns are known to be colonized by AM fungi. We conducted a factorial greenhouse experiment with three levels of As (0, 50, and 100 mg kg(-1)) and P (0, 25, and 50 mg kg(-1)) and with and without Chinese brake fern colonized by a community of AM fungi from an As-contaminated site. We found that the AM fungi not only tolerated As amendment, but their presence increased frond dry mass at the highest As application rate. Furthermore, the AM fungi increased As uptake across a range of P levels, while P uptake was generally increased only when there was no As amendment. These data indicate that AM fungi have an important role in arsenic accumulation by Chinese brake fern. Therefore, to effectively phytoremediate As-contaminated soils, the mycorrhizal status of ferns needs to be taken into account. 相似文献
115.
Hawrot-Paw Małgorzata Koniuszy Adam Mikiciuk Małgorzata Izwikow Monika Stawicki Tomasz Sędłak Paweł 《Environmental science and pollution research international》2017,24(17):15022-15030
Environmental Science and Pollution Research - The purpose of this research was evaluation of the effect of soil contamination with waste coming from biomass gasification on chosen indicators of... 相似文献
116.
Xu Li Zimeng Liu Qing Xu Zhongyi Jiang Guoliang Ma 《Environmental Modeling and Assessment》2017,22(3):243-255
In this paper, we construct a multi-stage coordinated programming model under tax system to control SO2 emission. The model is based on an explicitly formulated SO2 abatement cost function created under Chinese condition. Analysis of the effectiveness and impact on the economy of the model is carried out with consideration of game theory. By solving the model, theoretical results show that the volume-based multi-stage SO2 tax system has two properties: effectiveness and equal-rate. Based on these theoretical results, empirical study is also performed using Chinese historical data. Compared with yearly single-stage programming model, the tax rate generated by the coordinated multi-stage programming model is time-invariant and rather moderate in scale. The total abatement cost among planning years in our model is 21.03 % less than the actual number and 6.68 % less than that in the single-stage situation. The tax payment suggested by our model is 10.62 % less than by the single-stage model. In general, a coordinated multi-stage programming model helps reduce the overall costs of environmental protection while achieving the same emission control target with less burden added to the economy. 相似文献
117.
Chen Yujun Guan Bin Wu Xingze Guo Jiangfeng Ma Zeren Zhang Jinhe Jiang Xing Bao Shibo Cao Yiyan Yin Chengdong Ai Di Chen Yuxuan Lin He Huang Zhen 《Environmental science and pollution research international》2023,30(5):11246-11271
Environmental Science and Pollution Research - In recent years, with global climate change, the utilization of carbon dioxide as a resource has become an important goal of human society to achieve... 相似文献
118.
Ma Xiaodong Xue Yongxuan 《Environmental science and pollution research international》2023,30(13):35588-35601
Environmental Science and Pollution Research - More and more emphasis is placed on the common development of economy and ecological environment in China’s development strategy, and one of the... 相似文献
119.
ABSTRACTThe present study was carried out to investigate the effect of three organic matters (stalk powder, microbial fertilizer, and manure) on Leymus chinensis germination, growth, and urease activity and available nitrogen (N) in coastal saline soil. The study was conducted in a completely randomized design with eight treatments: J0V0Y0, J1V0Y0, J0V1Y0, J0V0Y1, J1V1Y0, J1V0Y1, J0V1Y1, J1V1Y1. The notations were based on the quantities of each agent added to 1 kg of coastal saline soil: J0 – no straw powder, J1 – 0.2 kg straw powder, Y0 – no manure, Y1 – 0.3 kg manure, V0 – no microbial fertilizer, V1 – 0.2 L microbial fertilizer, each in quantic repeat. L. chinensis was sown as 50 seeds per pot. Results indicated that addition of organic agents exerted a significantly enhanced germination, increase in fresh weight and elevated soil urease activity. Soil available N levels were significantly positively correlated with soil urease activity and fresh weight, but not with germination rate. It is noteworthy that the halophyte L. chinensis showed improved characteristics when grown in coastal saline soil with addition of organic amendments. 相似文献
120.
Ning Zong Peili Shi Minghua Song Xianzhou Zhang Jing Jiang Xi Chai 《Environmental management》2016,57(3):531-542