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1.
DR电热锅炉     
《中国环保产业》2002,(7):44-45
由上海广安工程应用技术有限公司开发、上海市环境保护局推荐的DR电热锅炉适用于以水为媒作为冷、热中央空调的热源;可供生活和生产所需的饱和蒸汽和高温热水;用低谷电产生廉价的生活热水和开水;用电热将导热油加温到250℃~280℃,用于印染、食品、医药、以及其他需烘干技术的场合。主要技术内容一、基本原理通过电热锅炉的电热元件把电能转化为热能加热水生成热水或蒸汽,由于电热锅炉没有燃烧过程,因此不产生任何有害气体及废渣等环境污染物。二、技术关键制造符合热工水力原理的耐压的锅炉本体;研制长寿命、大功率,能承受…  相似文献   

2.
生物活性炭技术在水处理中的研究进展与应用   总被引:3,自引:0,他引:3  
总结了生物活性炭(BAC)技术在净水处理、废水处理和污水再生利用处理中的应用;阐述了生物活性炭对污染物的去除机理;介绍了生物活性炭技术在水处理中(包括给水深度处理、多种工业废水及生活污水处理)的最新应用研究成果及该技术的发展方向。  相似文献   

3.
从给水排水规划、工艺设计、施工管理、运行费用、运行监管、产权明晰和运行管理考核体系等方面对巢湖流域农村生活污水处理设施的运行机制进行了探讨,为如何保证农村污水处理系统的稳定运行提供参考。  相似文献   

4.
秦皇岛地区地热资源丰富,地下热水被广泛开发利用。地下热水开发利用过程中出现的环境问题,表现在高矿化热水上涌引起的土壤盐碱化和局部地区水温逐年下降。为解决这些环境问题,必须加强管理,制订合理的地下水开采方案;改进落后的成井工艺,由专业队伍施工水井,采取必要措施切断冷热水的水力联系;在高矿化热水井附近打回灌井,阻止土壤盐碱化。  相似文献   

5.
曾经有许多人把地下热水与煤、石油及天然气等能源作了对比,认为地下热水具有分布广泛、易于开采、成本低廉、清洁干净,并可直接利用等独特的优点,是一种很有开发前景的新能源。因此,目前对地下热水的开发和利用已越来越广泛,无论是在工农业生产上还是在日常生活中都在不同程度地直接或间接地利用地下热水中的热能或化学成分。近年来,我国的许多大、中城市都在勘探、开发和利用地下热水。据报道,北京亚运会主会  相似文献   

6.
我国华北平原分布有大小不等、形状各异的地下热水矿床;赋存于石灰岩地层形成的地质构造凸起部位的地下热水富水性好,井产水量大,自喷能力强,水质好,矿化度低,温度高,具有较高的开发利用价值。华北平原地下热水的热源与第三纪侵入的火成岩无关。地下热水的补给来源是山区大气降水渗入地下经过较大的构造断裂带和碳酸盐岩地层岩溶溶洞、断裂裂隙深循环以后形成的。地下热水的温度主要取决于水循环的深度。  相似文献   

7.
《绿色视野》2014,(11):17-19
在皖北地区,去澡堂里泡个澡,然后聊天、打牌是很多普通老百姓生活中的乐事。然而,很多澡堂都是用燃煤锅炉烧热水,造成了空气污染,成为老百姓关心的热点问题。9月15日至18日,记者跟随2014年全省环保专项行动督察组在亳州市和阜阳市督察时了解到,亳州市和阜阳市正在全力推进燃煤锅炉的整治工作,对燃煤锅炉进行“改气”、“改电”、“改热水”等改造,以期彻底解决燃煤锅炉的污染问题。  相似文献   

8.
生物活性炭技术在欧洲水处理中的应用研究与发展   总被引:14,自引:1,他引:14  
胡静  张林生 《环境技术》2002,20(3):33-37
介绍了生物活性炭(BAC)技术在欧洲水处理中(包括给水深度的处理,多种工业废水及生活污水处理)的最新应用研究成果及该技术的发展方向。  相似文献   

9.
通过介绍《给水工程》课程的性质和作用,分析目前《给水工程》课程教学中存在的主要问题,对课程今后的教学思路提出了新设想,主要包括:依托学科建设优势,引入科学研究新成果,构架全新课程内容体系;尝试采取"课堂+网络辅助"教学模式;采用多媒体教学和传统讲授相结合的理论教学手段和课堂演示与工程现场结合、教师演示与学生动手结合、经典演示与现代高科技结合、传统演示与多媒体结合的实践教学手段;采用变一考为多考和加重平时成绩的课程考核方式等。  相似文献   

10.
文章分析了目前长庆油田站场生活污水处理工艺存在的问题,对生活污水处理工艺进行了改进,采用膜生物反应器工艺处理生活污水以得到优质的中水,从而回收利用。通过对实际工程进行水质监测,COD、氨氮、浊度的去除效果好于GB 18920-2002《城市污水再生利用城市杂用水水质》中冲厕、绿化等用水要求。通过中水回用,形成"给水→利用→处理→循环利用"的中水回用模式,既节约了新鲜水,又减少了污水排放,保护了油区生态环境。  相似文献   

11.
Prior to Anglo-European settlement, fire was a major ecological process influencing the structure, composition and productivity of shortgrass prairie ecosystems on the Great Plains. However during the past 125 years, the frequency and extent of grassland fire has dramatically declined as a result of the systematic heavy grazing by large herds of domestic cattle and sheep which reduced the available levels of fine fuel and organized fire suppression efforts that succeeded in altering the natural fire regime. The greatly diminished role of recurrent fire in these ecosystems is thought to be responsible for ecologically adverse shifts in the composition, structure and diversity of these grasslands, leading specifically to the rise of ruderal species and invasion by less fire-tolerant species. The purpose of this study was to evaluate the ecological effects of fire season and frequency on the shortgrass prairie and to determine the means by which prescribed fire can best be restored in this ecosystem to provide the greatest benefit for numerous resource values. Plant cover, diversity, biomass and nutrient status, litter cover and soil chemistry were measured prior to and following fire treatments on a buffalograss-blue grama shortgrass prairie in northeastern New Mexico. Dormant-season fire was followed by increases in grass cover, forb cover, species richness and concentrations of foliar P, K, Ca, Mg and Mn. Growing-season fire produced declines in the cover of buffalograss, graminoids and forbs and increases in litter cover and levels of foliar P, K, Ca and Mn. Although no changes in soil chemistry were observed, both fire treatments caused decreases in herbaceous production, with standing biomass resulting from growing-season fire approximately 600 kg/ha and dormant-season fire approximately 1200 kg/ha, compared with controls approximately 1800 kg/ha. The initial findings of this long-term experiment suggest that dormant-season burning may be the preferable method for restoring fire in shortgrass prairie ecosystems where fire has been excluded for a prolonged time period.  相似文献   

12.
While previous studies have examined how forest management is influenced by the risk of fire, they rely on probabilistic estimates of the occurrence and impacts of fire. However, nonprobabilistic approaches are required for assessing the importance of fire risk when data are poor but risks are appreciable. We explore impacts of fire risk on forest management using as a case study a water catchment in the Australian Capital Territory (ACT) (southeastern Australia). In this forested area, urban water supply and timber yields from exotic plantations are potential joint but also competing land uses. Our analyses were stimulated by extensive wildfires in early 2003 that burned much of the existing exotic pine plantation estate in the water catchment and the resulting need to explore the relative economic benefits of revegetating the catchment with exotic plantations or native vegetation. The current mean fire interval in the ACT is approximately 40 years, making the establishment of a pine plantation economically marginal at a 4% discount rate. However, the relative impact on water yield of revegetation with native species and pines is very uncertain, as is the risk of fire under climate change. We use info-gap decision theory to account for these nonprobabilistic sources of uncertainty, demonstrating that the decision that is most robust to uncertainty is highly sensitive to the cost of native revegetation. If costs of native revegetation are sufficiently small, this option is more robust to uncertainty than revegetation with a commercial pine plantation.  相似文献   

13.
ABSTRACT: Runoff was measured from a 564-ha catchment located on the Entiat Experimental Forest for nine years before a severe wild-fire in 1970 destroyed the mixed conifer vegetation. Runoff records from the Chelan River (2 393 km2) were used as control data for determining changes in water yield during the seven years following the fire. The first post-fire year was a period of transition in which the soil profile retained more water than in previous years and measured runoff was 8.9 cm greater than the predicted value based on pre-fire conditions. Runoff from the burned catchment during subsequent years was much greater than measured values before the fire. Measured minus predicted runoff, based on the pre-fire calibration equation, varied from 10.7 cm during the dry year of 1977 to 47.2 cm during the abnormally wet year of 1972. Flow duration curves indicated that runoff at each percent value after the fire was at least double the comparable pre-fire value. Sediment production increased dramatically after the fire because of increased flow rates, increased overland flow caused by reduced infiltration capacity, and mass soil movement. Sediment yield is beginning to decrease as stream channels become stabilized and vegetation on upper slopes improves infiltration capacity.  相似文献   

14.
Of the natural processes that concentrate dispersed environmental contaminants, landscape fire stands out as having potential to rapidly concentrate contaminants and accelerate their redistribution. This study used rainfall simulation methods to quantify changes in concentration of a widely dispersed environmental contaminant (global fallout 137Cs) in soils and surface water runoff following a major forest fire at Los Alamos, New Mexico, USA. The 137Cs concentrations at the ground surface increased up to 40 times higher in ash deposits and three times higher for the topmost 50 mm of soil compared with pre-fire soils. Average redistribution rates were about one order of magnitude greater for burned plots, 5.96 KBq ha(-1) mm(-1) rainfall, compared with unburned plots, 0.55 KBq ha(-1) mm(-1) rainfall. The greatest surface water transport of 137Cs, 11.6 KBq ha(-1) mm(-1), occurred at the plot with the greatest amount of ground cover removal (80% bare soil) following fire. Concentration increases of 137Cs occurred during surface water erosion, resulting in enrichment of 137Cs levels in sediments by factors of 1.4 to 2.9 compared with parent soils. The elevated concentrations in runoff declined rapidly with time and cumulative precipitation occurrence and approached pre-fire levels after approximately 240 mm of rainfall. Our results provide evidence of order-of-magnitude concentration increases of a fallout radionuclide as a result of forest fire and rapid transport of radionuclides following fire that may have important implications for a wide range of geophysical, ecosystem, fire management, and risk-based issues.  相似文献   

15.
Dead plant tissues and ash from a prescribed fire play an important role in nutrient balance and cycling in the Florida Everglades ecosystem. The objective of this study was to assess the dynamic changes in total phosphorus release (TPr) from ash or tissues of either cattail (Typha domingensis Pers.) or sawgrass (Cladium jamaicense Crantz) to water. Natural-dead (senesced-dead) and burning-dead (standing-dead due to a prescribed fire) cattail and sawgrass were collected from highly (H) and moderately (M) impacted zones in the Florida Everglades. This experiment was conducted by incubation and water-extraction of the materials in plastic bottles for 65 d at room temperature (24 +/- 1 degrees C). Results showed that 63 to 88%, 17 to 48%, 9 to 20%, and 13 to 28% of total P (TPp) were released as TPr from cattail and sawgrass ash, cattail tissues from the H zone, cattail tissues, and sawgrass tissues from the M zone, respectively. TPp means total P of plant tissues, whereas TPr is total P release from the tissues or ash. Most of the TPr was released within 24 h after burning. The quick release of TPr observed in this experiment may help explain the P surge in the surface water immediately following a fire in the marsh. These findings suggest that prescribed burning accelerates P release from cattail and sawgrass. They also imply that it is very important to keep the water stagnant in the first 24 h to maximize the benefits of a prescribed fire in the Everglades.  相似文献   

16.
城镇居住区的生活污水资源化越来越受到关注,掌握其水质水量变化趋势对收集、处理和资源化利用十分必要。分别以北方某城市、南方某城市、东部某城市的典型居住区为例,开展了水质水量调查。研究表明,居住区的水量变化规律有很强的地区差异性,且与当地的生活习惯有很大关系。北方地区的污水各项污染物浓度平均比南方地区高10%。主要污染物的浓度与用水量有一定相关性,除去夜间的洗浴时间,在用水高峰期尤其是清晨期间浓度较高。  相似文献   

17.
ABSTRACT: About one-third of all West Virginians obtain domestic water from private water wells. In this research, mail and telephone surveys were used to investigate household responses to bacteria, mineral, and organic chemical contamination of domestic water supplies. Of households who were informed of contamination and acknowledged the problem, over 85 percent took action to avoid exposure to water contamination problems. The most common action was to clean and/or repair the water system (55.9 percent of valid surveys). Approximately 45 percent of households made investments of either a water treatment system, a new water source, or correction of contamination source. The average, annual economic cost of rural household actions was $320 for bacteria, $357 for minerals, and $1,090 for organic contamination. These economic costs represent a lower bound estimate for rural household willingness-to-pay (WTP) for a reduction in domestic water contamination from government action. On average, investment actions had lower annual economic costs than noninvestment actions of boiling and hauling water so that households who undertook investment actions in response to water contamination would have a lower WTP for government action to reduce water contamination. When effectiveness of water treatment systems was evaluated, treatment systems which require minimal household maintenance were found to reduce exposure to water contamination to safe levels as households intended when they installed the system. Treatment systems which were commonly ineffective included those which required continual maintenance (e.g., chiorinators) or were not designed to solve the contaminant problem for which they were purchased (e.g., filter systems for bacteria).  相似文献   

18.
The aim of this paper is to highlight key social and economic drivers crucial to understanding community acceptance and adoption of decentralised water systems. The review focused on social science literature pertaining to alternative forms of household water, with an emphasis on research examining decentralised water acceptance. Researchers consistently reported that most communities were open to alternative water sources for domestic applications; however, this was highly dependent upon the level of personal contact with the water. Acceptance and adoption of alternative water technology, such as decentralised systems, was influenced by risk perception, water culture, and threat perception. Motivational drivers were also identified as potentially influencing adoption of decentralised systems. A clear limitation of the literature was found to be an over-reliance on measuring people's intentions to adopt alternative water systems and building a conceptual understanding of acceptance solely on hypothetical water supply scenarios. Further, within the social science literature there appears to be a skewing towards focusing on acceptance of centralised alternative water, such as recycled and desalinated water systems. Although there are some research outcomes that are generalizable to the decentralised water context, it is clear that there is a significant gap in the knowledge base of social drivers specific to the acceptance of decentralised water systems and the factors contributing to its widespread use. It is recommended that future research focus on examining public attitudes relevant to decentralised water systems, as well as adoption behaviours among current users of these systems. This will assist in developing policies specific to domestic decentralised water use.  相似文献   

19.
We employed qualitative methods to explore how conflict over water collection and use impacts women, and the role that women play in water management and conflict resolution in Marsabit, Kenya. Conflicts between domestic and livestock water led to insufficient water for domestic use and intra-household conflict. Women’s contributions to water management were valued, especially through informal initiatives, though involvement in statutory water management committees was not culturally appropriate. Promoting culturally appropriate ways to involve women in water management, rather than merely increasing the percentage of women on water committee, may reduce conflicts and increase women’s access to domestic water supplies.  相似文献   

20.
Native rangelands of the southwest part of the province of Santiago del Estero, Argentina, are a key source of forage for cow-calf operations. The objectives of this study were to delineate the ecosystem units of the area, to describe the associated plant communities and to interpret the role that physical factors and disturbances such as fire and grazing have had in the changes of the structure of these plant communities. This information is needed for developing recommendations for grazing management, for prescribing appropriate improvement practices (e.g. shrub control, prescribed fire) and as guidelines for future research. The ecosystem was divided into smaller units using a hierarchical method, the categories of practical importance being 'range unit' and 'range site'. They represent the catchment and hillslope scale of the water runoff-runon phenomenon, respectively. Vegetation was sampled using a block and cluster sampling design, registering tree, shrub, forb and grass species frequency, and the standing aerial biomass of the herbaceous layer in a sampling unit=1 ha. Environmental data (topographic position, fire frequency, current and past use, and tree and shrub cover) were also registered for each sampling unit. Indirect ordination of sampling units classified according to range units and range sites, and correlation with environmental variables were performed using multidimensional scaling (MDS) as well as the vector fitting technique. Standing forage and stocking rate were estimated from biomass data. Results indicate that 'range site' is the ecosystem unit that should be considered for management purposes since it correlates well with plant communities: tall, hardwood forests are located on upland sites, woodlands are located on midland sites and savannas are located on lowland sites. Dense shrub thickets dominate in areas rated in poor condition, irrespective of range site. Disturbances such as fire and current and past use have a significant positive and negative correlation with range condition, respectively, suggesting that a state and transition model would explain vegetation dynamics better than the succession model. The estimated stocking rate in lowland sites in good condition was 2 ha UG(-1), while in upland sites in poor condition the stocking rate was 90 ha UG(-1). Active (fire, mechanical treatments) rather than passive (grazing management) methods should be used for range improvement in order to achieve the full potential of the ecosystem.  相似文献   

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