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Sewage, particularly the domestic variety, is the major polluter of the aquatic ecosystem in developing Asian countries. Besides eutrophication, it causes a number of waterborne diseases. The growing urbanization in relation to deteriorating water quality; existing practices of sewage management through treatment; reuse and recycling; as well as the legal support to curb pollution are discussed in regard to China, India, Korean Republic and Jordan. Some meaningful suggestions are made for improved sewage management and pollution control.

Pakistan is an agricultural country having the world's largest canal irrigation system. Indus basin that covers 70 percent of irrigated area for crop production is the major source of water in the country. Owing to rapid increase in population and uncertain environmental conditions, this water is not adequate to cope with the crop water requirement and needs additional means to provide extra water for agricultural purposes. The main source of irrigation is canal and ground water but the quality of ground water is so poor for the sustainability of agriculture system. To cope with the present demand, use of municipal sewage water that consists of domestic liquid waste, as well as industrial effluents, is becoming a common practice. The present study aims to reflect the hazardous effects of sewage water on the environment, with the main focus on heavy metals and chemical composition of soil and vegetables.

Industrial effluent was collected from one ghee mill, one flour mill, three textile industries and three hosieries located in Faisalabad, an industrial city of Pakistan highly affected with water pollution. All water samples were analyzed for pH, EC, SAR and RSC. Water analysis was also carried out for various nutrients and heavy metals (K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺). Soil samples from various depths (0‐15, 15‐30, 30‐60, 60‐90 and 90‐120 cm) were taken to analyze for EC, pH, SAR, Na⁺¹, SO₄, K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺ after irrigation with canal water and sewage water. Cadmium, lead and copper concentration was determined in various vegetables grown in areas irrigated with canal water and industrial effluents to determine their final concentration in the final product ultimately affecting the human health.

Although the sewage water is a source of many nutrients, it also includes a significant amount of heavy metals like Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺, Pb²⁺ and pathogens. Extensive use of this effluent for irrigation purpose has resulted in an upsurge of such metals in soils and various crops, which ultimately resulted in clinical problems in human beings.

The present study reflects the composition of sewage water and heavy metal accumulation in soil, as well as crops. It further highlights the different potential hazards to humans due to these contaminants.

Investigates the green cost attributable to water consumption in the hotel industry and accommodation operations in Hong Kong. An abatement cost approach plus a prorated model were used in the green costing. The study surveyed 20 hotels on the energy consumption in 1994‐1996 and performed green costing on the major water uses in hotels. Results indicate that green costs per room, attributable to water consumption in hotels range from HK$3.657 to HK$7.641. Implications for green reporting at property level and industry level are discussed, and recommendations are made for future research.

The demand of sewage treatment plants is increasing day by day, especially in the countries like India. Biological and chemical unit of such sewage treatment plants are critical and needs to be designed and developed to achieve desired level of reliability, maintainability and availability.

This paper investigates and optimizes the availability of biological and chemical unit of a sewage treatment plant. A novel mathematical model for this unit is developed using the Markovian birth-death process. A set of Chapman–Kolmogorov differential equations are derived for the model and a generalized solution is discovered using soft computing techniques namely genetic algorithm (GA) and particle swarm optimization (PSO).

Nature-inspired optimization techniques results of availability function depicted that PSO outperforms GA. The optimum value of the availability of biological and chemical processing unit is 0.9324 corresponding to population size 100, the number of evolutions 300, mutation 0.6 and crossover 0.85 achieved using GA while PSO results reflect that optimum achieved availability is 0.936240 after 45 iterations. Finally, it is revealed that PSO outperforms than GA.

This paper investigates and optimizes the availability of biological and chemical units of a sewage treatment plant. A novel mathematical model for this unit is developed using the Markovian birth-death process.

Availability model of biological and chemical units of a sewage treatment is developed using field failure data and judgments collected from the experts. Furthermore, availability of the system has been optimized to achieve desired level of reliability and maintainability.

A literature review was carried out of the health impacts of incineration, landfill, composting, landspreading sewage sludge and sewage discharges. A protocol for making judgements about the strength and reliability of the evidence was applied using an algorithm with defined criteria. Possible judgements were “convincing”, “probable”, “possible” or “insufficient”. The review found that the evidence linking any adverse health outcomes with incineration, landfill or landspreading sewage sludge was “insufficient” to claim a causal association. The evidence is “insufficient” to link residence near a centralised composting facility with adverse health outcomes but it is “possible” that working at a centralised composting facility causes health problems. Working in sewage treatment plants “probably” causes gastrointestinal tract problems, headache, fatigue and airways symptoms. The only “convincing” evidence is that gastrointestinal symptoms result from bathing in sewage contaminated recreational waters.

The purpose of this paper is to assess the occurrence and risk of dispersion in the environment of antibiotic-resistant microorganisms from sanitary sewage sludge produced in two conventional wastewater treatment systems adopted in the West of the State of Paraná, Brazil.

The sludge samples were collected for three months from two wastewater treatment plants, totaling six sample points, and sent to the laboratory where the physical-chemical and biological determinations were performed.

This work made possible to find that the sludge produced in the sewage treatment plants presents potential risks related to the spread of microorganisms due to the occurrence of resistant isolates of Escherichia coli and Salmonella sp. It was also possible to detect that the largest concentrations of metal ions in the sludge favored the occurrence of bacterial resistance to antibiotics. The occurrence of pathogens, heavy metals and other emerging pollutants in sewage indicates that the sludge requires proper treatment, to provide safe agricultural reuse or disposal.

The techniques applied for monitoring sludge were effective to check the risk of resistant microorganisms input into the environment. Studies concerning sewage treatment plants’ final effluents can bring additional data about the incorporation of such microorganisms into aquatic environments.

The results made possible to observe the need to provide post-treatment for the sludge, especially of the sludge obtained from the anaerobic fluidized bed reactor, since the removal of pathogens, as well as the nutrients, is not satisfactory.

This paper investigates the internal factors driving public-private partnership (PPP) adoption for water services in South Korea and Singapore.

This study utilizes a comparative cross-national case study of PPPs in the area of water services by focusing on the similarities and differences between the two countries.

The findings show that while South Korea has employed the PPP model mostly to expand and modernize their sewage systems, Singapore has used PPPs to build and operate desalination facilities that produce potable water through the treatment and filtration of wastewater. The study also demonstrates that fiscal stress and political incentives stemming from socio-economic pressures are the respective critical factors in South Korea and Singapore’s execution of PPP-driven water infrastructure.

Through exploring why and how PPPs have been adopted in the specific context, this paper might be helpful to enhance our understanding of the variations and common factors in the policy adoption process within the Asian context.

To develop an in‐pipe robot to be used for inspecting pipes that are laid underneath a waste disposal site and for sampling sewage water leaking from holes around the pipe.

The paper presents a compact design of the robot's mechanical and electronic systems, and develops a simple and practical method for determining the hole position using some characteristics of this in‐pipe robot.

Development of a multi‐functional in‐pipe robot with elaborate design is feasible, and multiple trapezoidal‐shaped wheels have good capabilities of providing the robot large traction force and keeping the robot horizontal in pipeline. A good mechanical structure design can greatly reduce control and computation cost by using some specific features of the object system.

This study provides guidance for future design of multi‐functional in‐pipe robots.

The combination of a vision system and a manipulator can perform in‐pipe inspection and other different tasks. The developed robot has already been used practically by a large Japanese construction company for pipe inspection and sewage sampling.

An in‐pipe robot is developed that cannot only implement pipe inspection, but which can also take sewage water samples. Most of such multiple‐functional small robots are still in development and rarely reported.

To determine the influence of alkali components (especially Ca compounds) on the hematite phase formation during thermal processing of sewage sludge and the observation of transformations proceeding at different ratios of Ca to FePO₄.

The model compositions were heated to temperatures of 600°C and 950°C, then calcined within 3 hours without mixing. Cooled products were subjected chemical analysis regarding the content of phosphorus that was soluble in cold water, 0.4 per cent HCl, 2 percent citric acid and aqua regia as well as crystallographic identification.

On calcining at 600°C, CaO reacts with FePO₄, forming hydroxylapatite. The hematite phase which is insoluble in mineral acids crystallizes above 600°C. Further increasing the calcining temperature leads to transformations resulting in Ca₉Fe(PO₄)₇ and hematite formation. Molar ratios of CaO to FePO₄ · 2H₂O of 1.0 and 2.0 lead to hematite phase formation and increase the availability of phosphorus compounds (characterized by phosphate solubility in 0.4 percent HCl and 2 percent citric acid) in compositions after calcining.

The addition of CaO to sewage sludge before the combustion process should be beneficial from the point of view of further extraction of phosphorus compounds from the ash obtained. Suitable CaO addition favours iron binding into the hematite phase and raises the solubility of the phosphorus compounds in the ashes formed.

This paper is a new source of information which complements existing knowledge about phosphorus recovery from sewage sludge.

Examines the fate of heavy metals in sewage water and the sludge produced. Investigates the level of metals before and after the use of chemical coagulants as well as throughout every process of the plant. Results reveal that the present upgrading of the plant has a remarkable improvement in the performance of the sewage treatment. Concludes that such upgrading of the plant reduces sewage tax because of the improvement in performance. In addition, the hydrolysis of the pre‐treated sludge can improve the de‐nitrified process and therefore can save energy, while the application of lime can be a substitution for enlarging the plant itself.