Use Of Sewage Effluent Research Articles

Assessment of Growth Promoting Ability of Three Cyanobacterial Isolates Under Sewage Water Irrigation

Heavy metal pollution from the increased use of sewage effluent for irrigation is posing a hazard to agricultural ecosystems. Thus, a reliable and simple method of reducing the impact of heavy metals on plant growth is required. In the present study, cyanobacterial species were isolated from the sewage water irrigated soil of Rohtak city, Haryana, India, and characterized by various biochemical parameters. The cyanobacterial filtrates were then used to analyze their effects on the growth performance of rice seedlings under various concentrations of sewage wastewater. The results revealed a statistically significant increase in biomass, photosynthetic pigments, nitrate reductase activity, plumule, and radical length of rice seedlings by application of cyanobacterial filtrates. The antioxidant system (peroxidase enzyme and catalase enzyme activity) was also found to be stimulated. As compared to introduced species, the extracts of isolated species had a more favorable, statistically significant effect on rice seedlings. Our study indicated that these isolates have a high tolerance against heavy metals and are potentially useful as biofertilizers for the crops in sewage water irrigated agroecosystems.

Heavy metal concentrations in soil and vegetables irrigated with sewage effluent: A case study of Embu sewage treatment plant, Kenya

As a result of the increasing constraint in the availability of fresh water for irrigation, wastewater especially sewage effluent is being used for irrigation of agriculture fields, particularly in urban and peri‑urban centers. However, there is increasing concern over the associated potential health risks due to the dietary intake of contaminated vegetables. This study was conducted to analyze the levels of copper, zinc, cadmium and lead in sewage effluent, and in the vegetables and soil irrigated using this sewage effluent. Sewage effluent, soil and plant samples were collected and subjected to acid digestion to extract the heavy metals from the samples. Thereafter, concentration levels of the heavy metals were determined using Atomic Absorption Spectrophotometer (AAS). The mean concentrations of 0.484–1.834 mg/L, 1.432–4.612 mg/L, 0.015–0.353 mg/L, 0.011–2.123 mg/L for copper, zinc, cadmium and lead, respectively, were obtained in the sewage effluent which were above the WHO permissible levels in wastewater for irrigation. Due to continuous use of sewage effluent for irrigation, gradual accumulation of heavy metals in the soil could occur which could eventually lead to increased uptake of the heavy metals by the growing vegetables. Therefore, to ensure food safety and the use of sewage effluent for irrigation, we suggest that it is important to conduct continuous monitoring and pollution control.

Managed aquifer recharge: study of undisturbed soil column tests on the infiltration and treatment capacity using effluent of wastewater stabilization pond

ABSTRACT Managed Aquifer Recharge (MAR) is a useful tool for the treatment and use of sewage effluent because it complements conventional treatment, recovers the aquifer and minimizes risk of saltwater intrusion. This study aims to investigate technical data to determine the treatment of wastewater stabilization pond effluent using undisturbed soil columns collected from a coastal watershed study area within the BRAMAR (BRAzil Managed Aquifer Recharge) project. The treatment efficiency was monitored by measuring physico-chemical parameters (BOD 5, COD, DOC, TSS, NH3 and NO3) in two columns filled with undisturbed sandy soil in which sewage effluent was infiltrated under unsaturated condition for 72 days with an average input flow of 10 mm h-1. Results indicated reduction greater than 60% of organic matter, suspended solids and ammoniacal nitrogen. However, high concentrations of nitrate in the outflow were detected originating from nitrification of ammoniacal nitrogen. Moreover, difficulties in relation to soil clogging were observed. Furthermore, this study brought relevant contributions to understanding the influence of the infiltration rate and ability to treat effluent from wastewater stabilization ponds using undisturbed soil columns. Future research should be undertaken to improve the pretreatment methods and the operation of a MAR system in the study area.

Nickel, lead and manganese content of forages irrigated with different sewage water treatments: A case study of a semiarid region (Sargodha) in Pakistan

The use of sewage water for agricultural purpose has tremendously increased during the last few years due to shortage of water availability, especially in semi-arid regions. Despite of many nutrients recycling advantages of sewage water, farmers are not fully aware of its harmful chemical composition. Heavy metals toxicity in soil and crops results from the long term use of sewage effluent for irrigation purposes. The present study was conducted to assess effect of sewage water on the uptake of Ni, Pb and Mn in different forage species with respect to the nutrient requirement of the grazing ruminants inSargodha,Punjab,Pakistan. Five samples each of six fodder species viz., Trifolium alexandrinum, Cichorium intybus, Avena sativa, Medicago polymorpha, Brassica campestris and Medicago sativa were collected from three fields irrigated with canal water, mix water (canal plus sewage water) and sewage water respectively. Pb, Ni and Mn concentration in the forage species during different treatments varied from 0.624 to1.672 mg/g, 7.364 to 10.17 mg/g and 5.136 to 12.422 mg/kg respectively. High value of Pb and Mn concentrations was observed during sewage water treatment. Lead is a non-essential element and is a very toxic metal. But in the present investigation Ni and Pb level in forages were below the toxic level, so the ruminants feeding on these forage species had no chance of Pb and Ni toxicity. On the other hand, Mn concentration in the forage species under observation was below the critical level. So the grazing animals at this location need continued mineral supplementation of Mn to prevent diseases caused by Mn deficiency, and to support optimum animal productivity. The objective of this study was to examine the potential for forage analysis as indicators of likely mineral deficiencies or excesses of grazing livestock during different sewage water treatments.

Potential of Waste Water Use for Jatropha Cultivation in Arid Environments

Water is crucial for socio-economic development and healthy ecosystems. With the actual population growth and in view of future water scarcity, development calls for improved sectorial allocation of groundwater and surface water for domestic, agricultural and industrial use. Instead of intensifying the pressure on water resources, leading to conflicts among users and excessive pressure on the environment, sewage effluents, after pre-treatment, provide an alternative nutrient-rich water source for agriculture in the vicinity of cities. Water scarcity often occurs in arid and semiarid regions affected by droughts and large climate variability and where the choice of crop to be grown is limited by the environmental factors. Jatropha has been introduced as a potential renewable energy resource since it is claimed to be drought resistant and can be grown on marginal sites. Sewage effluents provide a source for water and nutrients for cultivating jatropha, a combined plant production/effluent treatment system. Nevertheless, use of sewage effluents for irrigation in arid climates carries the risk of salinization. Thus, potential irrigation with sewage effluents needs to consider both the water requirement of the crop and those needed for controlling salinity build-up in the top soil. Using data from a case study in Southern Morocco, irrigation requirements were calculated using CROPWAT 8.0. We present here crop evapotranspiration during the growing period, required irrigation, the resulting nutrient input and the related risk of salinization from the irrigation of jatropha with sewage effluent.

Growth, chemical composition and soil properties of Tipuana speciosa (Benth.) Kuntze seedlings irrigated with sewage effluent

This study was carried out at a greenhouse of Sabahia Horticulture Research Station, Alexandria, Egypt, to study the effect of sewage effluent on the growth and chemical composition of Tipuana speciosa (Benth.) Kuntze seedlings as well as on soil properties for three stages. The irrigation treatments were primary-treated wastewater and secondary-treated wastewater, in addition to tap water as control. Therefore, the treated wastewater was taken from oxidation ponds of New Borg El-Arab City. Results of these study revealed that the primary effluent treatment explored the highest significant values for vegetative growth and biomass, compared to the other treatments. In addition, the higher significant concentration and uptake of chemical composition in different plant parts were obtained from the primary effluent treatment during the three stages of irrigation. It was found that the concentration of heavy metals in either plant or soil was below as compared to the world-recommended levels. These findings suggested that the use of sewage effluent in irrigating T. speciosa seedlings grown in calcareous soil was beneficial for the improvement of soil properties and production of timber trees, and also important for the safe manner of disposal of wastewater.

Usage of sewage effluent in irrigation of some woody tree seedlings. Part 3: Swietenia mahagoni (L.) Jacq.

A pot experiment was investigated to study the effect of sewage irrigation treatments (primary and secondary effluents) compared with tap water on the growth and chemical constituents of mahogany seedlings ( Swietenia mahagoni (L.) Jacq.) as well as soil chemical properties. The experiment was conducted at a greenhouse in the nursery of Timber Trees Research Department of Sabahia, Horticultural Research Station in Alexandria, Egypt, from June 2003 to December 2004 for three irrigation periods (6, 12 and 18 months). The sewage effluent waters were taken from oxidation ponds located in New Borg EL-Arab city and used directly for irrigation. The primary effluent treatment was superior than other treatments in improving the growth parameters (plant height, stem diameter, leaf area, leaves number, fresh and dry weights of leaves, shoots and roots and shoot/root ratio) and showed the highest concentration and total uptake of N, P, K, Cd, Ni, Pb and Fe in plant parts, followed by secondary effluent then tap water. The data revealed that soil salinity in terms of electrical conductivity of saturated paste (EC), CaCO 3%, organic matter% and soluble anions and cations were influenced significantly by primary or secondary effluent treatment. The data also showed that the use of sewage effluent for irrigation increased N, P, K and DTPA-extractable-heavy metals (Cd, Cu, Ni, Pb, Fe, Mn and Zn). The effects of sewage effluent on growth parameters and elements content in plant parts and treated soil were more pronounced as water treatments were used for long period. The results suggested that the use of sewage effluent in irrigating mahogany trees grown on calcareous sandy loam soil was an important agriculture practice for improving soil properties, increasing fuel and timber production, and is an economic and safe way to dispose wastewaters.

Effects of heavy metals contained in soil irrigated with a mixture of sewage sludge and effluent for thirty years on soil microbial biomass and plant growth

The use of sewage effluent as a source of nutrients and water in peri-urban crop production is widespread in developing countries. A study was conducted in 2005 at Crowborough and Firle farms (near Harare) to assess effect of Cd on microbial biomass and activity, effect of sewage sludge and effluent on soybean (Glycine max L (Merr)) nodulation, and uptake of Zn and Cu by lettuce ( Lactuca sativa L.), mustard rape ( Brassica juncea L.), covo ( Brassica napus) and star grass ( Cynodon nlemfuensis). The soil that was used had been irrigated with sewage sludge and effluent for 30 years. Soil collected from Crowborough farm was enriched with Cd to different concentrations (0.4–5 mg Cd kg −1 soil) using Cd(NO 3) 2 and microbial biomass C and N (chloroform-incubation extraction) and respiration rates (CO 2 evolution) determined. A similar experiment to determine the effect of repeated addition of small amounts of Cd to soil over time on the same parameters was conducted. Three vegetables and star grass were grown in a pot experiment and harvested at six weeks after transplanting for the determination of above ground dry matter yield, and Zn and Cu, uptake. In another pot experiment, two soybean varieties, Magoye and Solitaire, were harvested after eight weeks and nodule number and effectiveness, and above ground dry matter yield were then determined. Cd significantly decreased biomass C (68%) and N (73%). Microbial respiration also significantly decreased. It was concluded that long-term application of sewage sludge and effluent to soil has negative effects on soil micro organisms, including Rhizobia. These micro organisms are essential for N-fixation. The damage to Rhizobia, caused diminished nodulation of soybean. Mustard rape and lettuce can accumulate Zn and Cu beyond toxic limits without apparent reduction in growth thereby posing a serious concern to the food chain. The consumption of mustard rape and lettuce grown on soil amended with sewage sludge and effluent at Crowborough and Firle farms poses a health risk to people who consume vegetables grown in this area.

Impact of the Reuse of Domestic Waste Water for Irrigation on Ground Water Quality

Egypt planned to reclaim large areas in both the Eastern and Western desert fringes of the Nile Delta with an increasing use of sewage effluent from Greater Cairo. The Gabal el Asfar farm which has been irrigated with raw to primary treated sewage effluent for a period of seventy five years was selected as a pilot area to investigate the groundwater quality. This farm covering 3000 feddan (1250 ha), is located in the sandy area northeast of Cairo. The main objective of the study was to assess the impact of agricultural application of sewage effluent on groundwater quality. Observation wells were constructed and field and laboratory measurements were carried out in and around the Gabal el Asfar area. The water balance and mass balances have been assessed. The study yielded useful recommendations to decrease the impact on groundwater quality and possible risks in Gabal el Asfar, concerning 1) type and amount of pollution from sewage effluent, 2) design criteria to control possible spreading of pollutants, and finally 3) the use of groundwater in the area. The following comprises the main conclusions:*Irrigation with sewage effluent had a positive impact on salinity of the initially brackish groundwater. On the contrary, groundwater quality is negatively affected from sewage effluent with regard to nitrogen contents (ammonium and nitrate), phosphate, heavy metals and faecal coliforms.*The drinking water limit for nitrate is sometimes exceeded. Moreover, faecal coliforms are found in water from all shallow handpumps in the area. The general suitability of the groundwater is therefore limited while the use of handpumps for drinking water purposes should be avoided. High boron contents of sewage effluent indicate a risk for crops sensitive to boron.*The accumulation of heavy metals and phosphorus in the soil adversely affects the soil system.*Pretreatment of sewage effluent in Gabal el Asfar should be improved to limit the pollution of the aquifer. Industrial discharge in sewage effluent should be avoided.*Groundwater recharged by sewage effluent is mainly collected by drains in or at the borders of the area, so spreading of pollutants out of the area is largely controlled.

The Wastewater Disposal System of the City of Yokohama, Japan

Modern sewerage system construction in the City of Yokohama dates from 1950. During the ensuing years, the City actively promoted such construction. The first sewage-treatment plant was commissioned in 1962, and the City's percentage of sewered population (including treatment services) reached 85% in March 1990. This paper describes the outstanding development and record of the wastewater disposal system in Yokohama (which must be ranked ahead of other Japanese cities in this area), as well as the organization, technology, administrative and financing efforts that made this development possible. It also explains the notable features of these works, which include Japan's first fully-fledged centralized sludge treatment, improvement of combined sewerage systems, industrial effluent control, effective use of sewage effluent and sludge, and sewer user charges. In addition, it presents comments on the future tasks for the 21st century, including advanced wastewater treatment and the integrated information system on water environment.

Influence of prolonged use of sewage effluent in irrigation on heavy metal accumulation in soils and plants

AbstractTotal content of Fe, Mn, Zn, Cu, Pb, Cd, Ni and Co in soils irrigated with sewage effluent increased with increasing years of using sewage effluent in irrigation. Iron and Co applied to the soil from sewage effluent were immobilized mainly in unavailable form; Pb, Cd, and Ni in moderately available form; and Mn, Zn, and Cu in highly available form. The concentrations of Fe, Mn, Zn and Cu in tops of alfalfa and leaves of corn grown on these soils increased substantially with increased levels of available metal content of the soil, while those of other metals were little affected. As for orange, continuous increase in leaves metal content with time was found for Fe, Mn, Zn, Co and Cd. The concentrations of Cd, Co, Ni and Pb in corn grains and orange fruits were several times higher than normal, and this reduces their suitability for human consumption.

Prolonged Effect of Land Disposal of Human Wastes on Soil Conditions

Land disposal of human wastes is a comprehensive issue, where a series of aspects have to be considered. Few, if any, alternatives exist to this technology. No doubt future emphasis will be on sewage farming, which should result in the cultivation of new arid land. This paper addresses the prolonged effect of land disposal of human wastes on soil properties, as well as on the dissemination of enteric pathogens. In order to assess this impact, soil samples were collected from Gabal el Asfar sewage farm in Cairo to represent sandy soils irrigated solely, by surface flooding, with decanted sewage effluent for 0, 2.5, 5, 10, 15, 20, 30, 45 and 60 years. Sewage farming tended to build up the soil microbial population, particularly during the first five years. In all soils, human wastes increased total bacterial counts and promoted the proliferation of the physiological groups. This population would accelerate the oxidation of organic matter to available nutrients. It also resulted in a high increase in nitrogen, phosphorus, micro-nutrients, organic carbon and raised the water holding capacity and exchangeable cations. However, the prolonged use of sewage effluent would disturb the balance of nutrients in soil, as the pH shifted towards acidity. The most interesting observation in the present work is to record that neither soluble salts nor micro-nutrients reached any injurious level. But land disposal of human wastes should be excercised with caution and if it is intended to be applied, salts, pH and nutrient elements should be checked occasionally. From the hygienic point of view, faecal E. coli, which is considered to be an indicator for enteric pathogens, gave positive results in all sewaged soils. Hence, it is recommended, from the sanitary point of view, that no crops which come in contact with sewage effluent should be cultivated in a sewage farm.

Toxic effects of surfactants applied to plant roots

AbstractSix surfactants used as additives to pesticide sprays, were applied in aqueous solution to the roots of sorghum plants. After a few hours of exposure to the surfactant solution, ions and amino‐acids leaked from the roots into the ambient solution, presumably due to a loss of membrane integrity. After 2‐3 days, the plants wilted and, at high concentrations of surfactants, they died. Toxic effects varied with the surfactant and its concentration, but no clear relationship was found between the physical effect of lowering the surface tension, the release of solutes by the roots, and the injury caused to the plant. The results are of significance because of the proposed use of sewage effluents, known to contain detergents, for irrigation purposes in Israel.

The use of sewage effluent as power station cooling water

Formation of mineral scales in industrial and municipal systems causes service interruption, performance decline, and often a complete system failure. Control of mineral scales may include costly water purification to remove scale-forming components or a simple addition of antiscaling chemicals. Although the use of antiscalants has very long history, it still relies more on experience and empirical solutions than on fundamental understanding of mechanisms by which these chemicals can reduce or prevent scale formation. Challenges for scale control include fairly complex interactions in aqueous systems, changing water chemistry, pH and temperature changes, and application of corrosion and biofouling strategies that could compromise the effectiveness of antiscalants. It is generally accepted that antiscalants do not completely eliminate scaling tendency but can inhibit the nucleation and/or crystallization phases. The main mechanisms by which antiscalants can control the formation of mineral precipitates include threshold inhibition, crystal modification, sequestration (chelation), or dispersion. It is desirable to utilize antiscalants that rely on more than one mechanism to ensure reliable performance. The dominant classes of antiscaling chemicals nowadays include polyphosphates, organophosphonates, and various polyelectrolytes. Depending on the application in question, there are several experimental approaches that may be utilized to evaluate the optimal control strategy that is compatible with other goals of water treatment. They range from simple beaker tests to recirculating systems with and without heated surfaces, electrochemical impedance spectroscopy, and dynamic tube blocking experiments for high pressure and temperature applications. It is important to note that these experimental systems are effective in demonstrating relative performance of different antiscaling approaches but that the final adjustments have to be performed during field applications. Case studies discussed in this chapter include the application of specific chemicals for the control of mineral scales in cooling systems using secondary-treated municipal wastewater, scaling control in reverse osmosis desalination, and inhibition of barium sulfate scaling on the production casing during unconventional shale gas extraction.

Undesirable Plant Responses with Sewage Irrigation

A farmer using sewage effluent for irrigation is faced with the management problem of an uninterrupted supply of nutrient laden water that may contain toxic heavy metals. The yield and quality of marketable produce can be reduced if moderate levels of nitrogen are applied continuously, especially if the crop is a perennial. Plants can take up many of the minerals in sewage in excess of their needs. The plant becomes either toxic to its consumer or it dies from the mineral toxicity. Heavy metals are the biggest unknowns in the use of sewage effluent for irrigation. Once heavy metals become toxic in the soil solution, they are difficult to remove from the solution. Heavy metals will accumulate in the soil and become toxic unless the source of the heavy metals in the effluent is eliminated.

Engineering Evaluation of Virus Hazard in Water

The evaluation is presented in terms of 13 questions: What virus infections may be spread through water? How important is water in transmitting virus disease? Can the coliform index be applied to an evaluation of enteric viruses in water? What is the status of control of infectious hepatitis transmission by shellfish? What is the status of sampling and detection procedures for viruses in water? How effective are sewage treatment processes in removing viruses? What risk is associated with use of sewage effluents for crop irrigation? Do birds or animals contribute health important viruses to water? Do enteric viruses multiply in water? What is the extent of virus contamination of water? How long do viruses survive in water? How significant is the hazard resulting from recreational use of impounded sources of drinking water supply? How effective are water purification processes in removing viruses? The report concludes that, while further study is desirable, existing technology and careful, vigilant plant operation can provide an acceptable level of protection for water users.

Industrial Water Requirements

Industrial water use accounts for almost half of the water withdrawn in the U.S., excluding hydroelectric power. Availability of process water continues to be one of the main reasons for construction of new plants along inland waterways, with about 40 per cent of the new plants being in the chemical and petroleum industries, whose water requirements for washing and cooling are very large. The article discusses the management of industrial water requirements, with emphasis on water reuse, use of sewage effluents, and plant location where abundant water resources are available.