摘要 :
Data from municipal and private wastewater treatment plants (WWTP) in the Dodecanese prefecture in Greece
was collected via a questionnaire and personal interviews, and was analyzed with respect to the operational status
of the pl...
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Data from municipal and private wastewater treatment plants (WWTP) in the Dodecanese prefecture in Greece
was collected via a questionnaire and personal interviews, and was analyzed with respect to the operational status
of the plants. The data was compared with the latest reports by the Greek Ministry of the Environment, which is
what is officially reported at a national level and to the European Union (EU), and what judges Greece’s
compliance with EU Directives. Our assessment is that the picture presented by the Ministry is limited and
optimistic when compared to reality, with many plants going unreported. This confirms what other researchers
have reported previously, and presents an update on operational status, specifically for the highly touristic and
ecologically sensitive island area of the Dodecanese. A short survey of the private WWTPs belonging to hotel
establishments reveals that, although they are expected to treat a large percentage of the wastewaters produced in
the islands during summer months, most of them operate poorly, while no regular checks are performed by public
health officials.
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摘要 :
Data from municipal and private wastewater treatment plants (WWTP) in the Dodecanese prefecture in Greece was collected via a questionnaire and personal interviews, and was analyzed with respect to the operational status of the pl...
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Data from municipal and private wastewater treatment plants (WWTP) in the Dodecanese prefecture in Greece was collected via a questionnaire and personal interviews, and was analyzed with respect to the operational status of the plants. The data was compared with the latest reports by the Greek Ministry of the Environment, which is what is officially reported at a national level and to the European Union (EU), and what judges Greece's compliance with EU Directives. Our assessment is that the picture presented by the Ministry is limited and optimistic when compared to reality, with many plants going unreported. This confirms what other researchers have reported previously, and presents an update on operational status, specifically for the highly touristic and ecologically sensitive island area of the Dodecanese. A short survey of the private WWTPs belonging to hotel establishments reveals that, although they are expected to treat a large percentage of the wastewaters produced in the islands during summer months, most of them operate poorly, while no regular checks are performed by public health officials.
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Urban and regional water demand for freshwater in the capital city of Hyderabad in Telangana state has been increasing rapidly over the last few decades. Hyderabad with a population of about 9.5 million is moving towards attaining...
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Urban and regional water demand for freshwater in the capital city of Hyderabad in Telangana state has been increasing rapidly over the last few decades. Hyderabad with a population of about 9.5 million is moving towards attaining the status of a megacity; due to high rate of immigration, infrastructural developments, host for IT hubs and many illegal settlements. Meanwhile, the main water bodies in the city have been encroached upon by private and government agencies. In this scenario, the water demands for the residents are not met with reasonable standards. Earlier, Hussain Sagar Lake was the source of drinking water and now the entire Hyderabad city has been depending on the other sources viz., Osmansagar, Himayatsagar lakes as well as Manjira, Singoor, Krishna and Godavari River. At present, the Greater Hyderabad Municipal Corporation (GHMC) receives water of approximately 2068 MLD from these sources. On the other hand, drainage system is present only in some parts of the city and it is connected to Sewage Treatment Plants (STPs); But sewage remain directly released into the water bodies mainly Musi river without treatment through open drains. In this study an attempt is made to review, study and propose to have a good water supply distribution system, sewerage system and also storm water system in Hyderabad city to maintain the quality of water bodies and river Musi.
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This study investigated 24 pharmaceuticals compounds belonging to the classes of analgesics, stimulants, anti-seizures, non-steroidal anti-inflammatory drugs (NSAIDs), and antibiotics in the sludge of 12 municipal sewage treatment...
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This study investigated 24 pharmaceuticals compounds belonging to the classes of analgesics, stimulants, anti-seizures, non-steroidal anti-inflammatory drugs (NSAIDs), and antibiotics in the sludge of 12 municipal sewage treatment plants (S-sludge) and 4 livestock wastewater treatment plants (L-sludge) located across Korea. Over 70% of the target compounds were detected in at least one sample of S-sludge and L-sludge. The total concentration of the target pharmaceutical compounds detected in S-sludge was 2.622-422.8 mg kg(-1) and the most dominant compound was acetylsalicylic acid (ASA: 0.374-367.0 mg kg(-1)) whereas in L-sludge, the total concentration was 43.87-156.8 mg kg(-1) and the most abundant compound was oxytetracycline (OTC: 34.54-86.39 mg.kg(-1)). Cluster analysis revealed two distinct groups: group A, which were S-sludge samples including ASA, carbamazepine (CBM), and others, and group B were L-sludge samples, dominated by antibiotics (CTC, OTC, LIN). The total daily load amount of the target pharmaceuticals in S-sludge was 0.010-268.9 kg day(-1) while the L-sludge was 0.021-0.529 kg day(-1). The estimated amounts of the target pharmaceutical discharged from S-sludge and L-sludge into the Korean environment were 150.2 +/- 47.94 ton yr(-1) and 15.05 +/- 5.671 ton yr(-1) respectively, but the discharged amount of antibiotics from S-sludge (6.945 ton yr(-1)) was lower than that from L-sludge (9.234 ton yr(-1)). (C) 2016 Elsevier Ltd. All rights reserved.
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Chinese privet is an invasive shrub that commonly infests roadsides and bottomland forests across the southeastern United States. Its aggressive growth and ability to prolifically sprout from the root collar and shallow lateral ro...
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Chinese privet is an invasive shrub that commonly infests roadsides and bottomland forests across the southeastern United States. Its aggressive growth and ability to prolifically sprout from the root collar and shallow lateral roots makes control very difficult. Individual plant treatment methods such as low-volume basal bark herbicide application with triclopyr are commonly used for Chinese privet control. However, little research has been done to examine optimal triclopyr concentrations and application timings for the low-volume basal bark method. Furthermore, little is known regarding basal bark treatment efficacy when plant size varies. To address these questions, field studies were conducted from 2009 to 2011 at two locations in east-central Alabama near Auburn and Opelika. The triclopyr butoxyethyl ester formulation was applied in January or March to Chinese privet shrubs across a range of sizes in a commercially available basal oil carrier at 24 (5% v/v(-1)), 48 (10% v/v(-1)), and 96 g L-1 (20% v/v(-1)). Additionally, a triclopyr butoxyethyl ester ready-to-use formulation (90 g L-1) was applied at 100% v/v(-1). Canopy defoliation, sprout height, and mortality were quantified at 6, 12, and 18 mo after treatment. Triclopyr at all concentrations was highly effective in defoliating Chinese privet and reducing height of new basal sprouts. However, mortality was concentration dependent. The 90 and 96 g L-1 treatments resulted in 88 and 89% mortality across timings, while the 24 and 48 g L-1 treatments resulted in 63 and 76% mortality. March applications were less effective as basal diameter increased, especially at the lower triclopyr concentrations where mortality fell to less than 40%. These results indicate that triclopyr is an effective treatment for Chinese privet control, but efficacy is influenced by concentration, application timing, and plant size.
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The main objective of this paper is to reach breakeven point between periodic planned maintenance and emergency maintenance, to reach this objective, periodic maintenance cost will be increased, then, it's necessary that emergency...
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The main objective of this paper is to reach breakeven point between periodic planned maintenance and emergency maintenance, to reach this objective, periodic maintenance cost will be increased, then, it's necessary that emergency maintenance should decreased and visa verse. The first step in this research was preparing a list of all maintenance activities to be done in water treatment plants according the history records of these plants, categorizing these activities into two main lists the first for periodic maintenance and the second for emergency. The next step is studying the effect of intensifying periodic maintenance on emergency maintenance. Using simulation model and starting intensifying periodic maintenance the effect will be determined calculating both periodic and maintenance cost and finally total maintenance cost. At the end of much iteration the result will be optimum maintenance cost. The suggested approach represents a flexible model to reach the optimal point for total maintenance cost through the process of balancing between and periodic and emergency maintenance costs.
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Performance assessment of water supply and wastewater services is today a major issue. Over the past six years, the National Civil Engineering Laboratory (Portugal) has been developing performance assessment systems for drinking w...
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Performance assessment of water supply and wastewater services is today a major issue. Over the past six years, the National Civil Engineering Laboratory (Portugal) has been developing performance assessment systems for drinking water treatment plants (WTPs) and wastewater treatment plants (WWTPs). In 2009, a national field-test was launched in Portugal, 'PASt21', involving 27 plants (10 WTPs and 17 WWTPs). This paper presents an overview of the second generation of the performance indicator (PI) systems for the overall performance assessment of WTPs and WWTPs, the extent to which the systems were applied in the 5-year study period (2006-2010), and the aggregated results (average, median, percentiles 25 and 75, maximum and minimum) of representative Pls in each assessment group. It was concluded that all indicators are relevant, and the results show the ability of the proposed PI systems to assess the overall performance of a given treatment plant. The aggregated results are very important for the continuous improvement of the plant performance through benchmarking and periodic reassessment of targets.
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This paper focuses on the development of a quality index applied to conventional water treatment plants (WTPQI) with the objective of providing a more consistent way of evaluating performance and comparing different plants. The me...
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This paper focuses on the development of a quality index applied to conventional water treatment plants (WTPQI) with the objective of providing a more consistent way of evaluating performance and comparing different plants. The methodology, based on the Delphi method, relies on the same principles used at the beginning of the 1970s in the formulation of the Water Quality Index (WQI). Afterwards, the WTPQI was applied to ten different Brazilian conventional water treatment plants, with horizontal sedimentation basins and variable sizes (average flow rates range from 100-4,300Ls~(-1)) and the results pointed out its usefulness as an instrument for plant evaluation. A significant correlation between plant performance and the WTPQI values was confirmed based on the filtered water turbidity, mainly for the rainy season when the raw water quality becomes harder to reach compliance with the drinking water standards. Therefore, these results open up the perspective of the use of the WTPQI as a reliable tool for the management of water supply systems.
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The paper describes a method that uses an empirical process observer to collect very comprehensive information about the conditions in an aeration plant. This process observer consists of a detailed on-line model (ASM1), a compone...
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The paper describes a method that uses an empirical process observer to collect very comprehensive information about the conditions in an aeration plant. This process observer consists of a detailed on-line model (ASM1), a component that calculates the inlet fraction on the basis of a few on-line measurements taken in the inlet channel, and a continuous adjustment of the model to the current conditions obtaining in the sewage treatment plant. The detailed insight into the current status of the process thus obtained is an ideal precon- dition for more advanced manual and automatic process con- trol concepts. The paper discusses feasible inlet fractioning concepts. The design principles for the follow-up component of the observer, based on simulation experiment sin a virtual test system, are explained and the results for the Hildesheim sewage treatment plant are described as an example.
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With the aim of reducing the environmental burden of decentralized wastewater treatment plants in India, this project investigated five primary materials (stainless steel (SS), mild steel (MS), glass fibre reinforced polymer (GFRP...
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With the aim of reducing the environmental burden of decentralized wastewater treatment plants in India, this project investigated five primary materials (stainless steel (SS), mild steel (MS), glass fibre reinforced polymer (GFRP), high density polyethylene (HDPE), and reinforced concrete cement (RCC)) in terms of the relative environmental impact that each would incur across 13 midpoint and 4 endpoint impact categories during the early life stages. The results showed that SS demonstrated substantially higher impact in total (5.47 Pt) and across each of the endpoint categories, most notably human health (3.12 Pt). Further investigations demonstrated that this was largely fed by the respiratory inorganics midpoint category that accounted for 50 % of the total impact (2.75 Pt), while global warming (0.93 Pt), non-renewable energy (0.70 Pt) and terrestrial ecotoxicity (0.62 Pt) were the only other considerable impacts. GFRP incurred the second greatest impact overall (2.32 Pt), while MS, RCC and HDPE followed with 1.82 Pt, 0.78 Pt, and 0.39 Pt respectively. HDPE afforded the greatest efficiency in all midpoint categories except carcinogens where RCC incurred the least environmental cost. Results were then compared with previous work and likely causal factors highlighted. Further study is recommended to investigate the longevity of the alternative materials in a wastewater containment role to support these results.
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