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Kolleru Lake, a wetland located in India, is one of the largest natural freshwater lakes and is an important sanctuary for indigenous and migratory birds, particularly in winter seasons. The lake is located between latitudes 16°32′ and 16°47′N and longitudes 81°05′ and 81°27′E. The lake is connected to the sea through the Upputeru River, at a distance of 60 km. The lake water is mainly used for drinking water, agriculture, fishing and aquaculture purposes. The lake ecosystem is deteriorating due to the industrial, agricultural and aquacultural activities. High volume sampler was used for the collection of air pollutants, namely suspended particulate matter, nitrogen oxide and sulfur dioxide from the lake at four locations over a period of one year. Water samples were collected from the lake in three seasons in a year over a period of three years and analyzed for water quality parameter, namely total suspended solids, hardness, chloride, sodium, chemical oxygen demand and biochemical oxygen demand. The aim of this study is to create the air and water pollution maps of Kolleru Lake using geographic information systems (GIS) for the better management of Kolleru Lake to control the pollution and also to avoid the risk of air and water pollutants on humans, aquatic organisms, birds and plants.

Total organic carbon (TOC), dissolved organic carbon (DOC) and other physicochemical parameters of the Birim River, which serves for drinking and domestic purposes for rural mining communities, were analysed to assess the suitability of water quality for human consumption.

In total, 40 samples were collected from 20 sampling sites during the rainy season from July to September and the dry season from December to February in addition to two repeat samples and two blank samples. Samples were analysed for physiochemical parameters and the results were compared with World Health Organisation standards (WHO).

Data obtained for both rainy and dry seasons indicated TOC ranged from 1.1 to 7.3 mg/L and DOC 1–7.2 mg/L; pH, 5.6–8.63; temperature, 23.3–29.3°C; turbidity, <1.00–869NTU; apparent colour, <2.5–600 mg/L Pt-Co; true colour <2.5–150 mg/L Pt-Co; alkalinity, 27.8–80.4 mg/L; total suspended solids, <1.00–998 mg/L; electrical conductivity, 82–184 µS/cm; and bicarbonate, 33.9–98.1 mg/L. Particulate organic carbon (POC) was constituted between 1 and 10% of the TOC. Values for pH, turbidity, total suspended solids, and true colour indicated contamination of the river. p -value of <0.05 between seasons for the physicochemical parameters also suggests that the water is polluted.

Water from the Birim River is unsuitable for human consumption and may constitute a serious health risk to the consumers.

The paper yields immense value to inhabitant of communities using surface water affected by mining activities, policy makers in sustainability. It warns of the unsuitability of water from the Birim River for human consumption due to the potential health risk to consumers.

The main purpose of this study is to provide a simple, efficient and economic system for saline wastewater treatment.

Industrial auditing was conducted to determine the water usage and wastewater characteristics during the manufacturing processes of pickling vegetables. In‐plant control measures were carried out prior to the end‐off‐pipe treatment. The treatment process was a simple pilot scale using two compartments alternated anaerobic fixed bed reactors (AAFBR).

The study indicated that applying the in‐plant control measures prior to final treatment of wastewater reduced the organic load and total suspended solids by almost 50 per cent. Post treatment of the end‐off‐pipe reduced the chemical oxygen demand, total suspended solids and dissolved salts by 84.2 per cent, 71 per cent and 52.4 per cent, respectively.

The proposed scheme was already implemented. The treated effluent from the factory was complying with the National regulatory standards for wastewater discharge into the public sewage network.

If additional evidence were needed of the connection between food supply and the spread of infectious disease, it would be found in a report recently presented to the Finsbury Borough Council by its Medical Officer of Health, Dr. GEORGE NEWMAN. It appears that in the early part of May a number of cases of scarlet fever were notified to Dr. NEWMAN, and upon inquiry being made it was ascertained that nearly the whole of these cases had partaken of milk from a particular dairy. A most pains‐taking investigation was at once instituted, and the source of the supply was traced to a farm in the Midlands, where two or three persons were found recovering from scarlet fever. The wholesale man in London, to whom the milk was consigned, at first denied that any of this particular supply had been sent to shops in the Finsbury district, but it was eventually discovered that one, or possibly two, churns had been delivered one morning, with the result that a number of persons contracted the disease. One of the most interesting points in Dr. NEWMAN'S report is that three of these cases, occurring in one family, received milk from a person who was not a customer of the wholesale dealer mentioned above. It transpired on the examination of this last retailer's servants that on the particular morning on which the infected churn of milk had been sent into Finsbury, one of them, running short, had borrowed a quart from another milkman, and had immediately delivered it at the house in which these three cases subsequently developed. The quantity he happened to borrow was a portion of the contents of the infected churn.

Artificial neural networks (ANN) are used as an alternative function approximation tool for predicting the performance of trickling filter treatment process in a municipal wastewater treatment plant, Solon, Ohio, USA, which uses a trickling filter followed by an activated sludge process. The treatment plant had an average monthly inflow flow rate of 2.92 mgd (million gallons per day). The average raw, settled, and final BOD (biochemical oxygen demand) was 449, 235 and 4.8 mg/l, respectively, while the corresponding value for TSS (total suspended solids) was 296, 131, and 6.1 mg/l. The overall removal efficiency for BOD and TSS was 98.93 per cent and 97.95 per cent respectively. The best ANN model for predicting the trickling filter effluent BOD and TSS has a prediction error of 31.45 per cent and 32.54 per cent respectively. The number of input variables, as well as number of nodes in hidden layer seemed not to have a definite effect on the prediction error for the ANN model. The prediction errors obtained with ANN models were lower than those obtained by multiple regression analysis.

The textile industry is one of the largest and most important industrial sectors in India. Because the textile industry consumes large quantities of water and produces highly polluted water discharge, its environmental impact is high. Water is expensive to use, treat and dispose of. Therefore, water conservation and reuse are critical necessity for the textile industry because decreasing water and wastewater treatment and recycling costs can be beneficial.

This research neutralized the pH during dyeing industry wastewater treatment. The system should be robust to erroneous sensor measurements. A pH meter was developed and used to monitor the pH of wastewater hourly before and after HCl treatment.

HCl was used to neutralize the pH of wastewater from 9 to 7.5. The amount of HCl was optimized depending on the wastewater. Three wastewater treatment methods were used, namely, HCl, wash water and reverse osmosis (RO) treatments. The HCl treatment was the most effective for decreasing the pH; the wash water treatment was the most effective for decreasing the total dissolved solids (TDS), total suspended solids (TSS) total hardness and chemical oxygen demand; and the RO treatment was the most effective for decreasing the biochemical oxygen demand, TDS, TSS, total hardness and Cl⁻ concentration.

The pH should be monitored during the textile dyeing because the addition of color to textile fabrics is the most effective at neutral pH. This study evaluated several parameters of wastewater, including pH, color, TSS and TDS. The fabricated digital pH meter provided superior results than conventional measuring devices. The goal was to maintain a neutral pH during dyeing and recycle wastewater to improve environmental sustainability. The newly developed digital pH meter was less expensive and more precise than traditional pH meters. Before reusing and recycling, wastewater underwent ultrafiltration and RO treatment.

The treatment performance of two‐stage secondary treatment consisting of a trickling filter followed by activated sludge process for treatment of combined municipal and industrial wastewater is determined. The municipal wastewater treatment plant is located in Solon, Ohio, where the treatment units include grit tanks, primary clarifiers, trickling filters, aeration tanks, secondary clarifiers, tertiary filters and chlorine contact tanks. The treatment performance data for a 12‐month period in 1989 was evaluated. The average total plant flow was 2.82 MGD (millions gallons per day) which consisted of 2.19 MGD industrial wastewater and 0.63 MGD domestic wastewater. Raw wastewater was of a high strength mainly due to the contribution from industrial sources. After different degrees of treatment the values of total suspended solids (TSS) and biochemical oxygen demand (BOD) met US Environmental Protection Agency standards. This plant has good treatment performance with 99 per cent BOD and 98 per cent TSS removal efficiencies.

This paper aims to select a type of mordant from aluminium salts, namely, aluminium sulphate, aluminium nitrate and polyaluminium chloride (PAC) with the lowest potential for contamination so that their use will minimise pollution from natural dye waste. It also aims to determine the pollution value of natural dye immersion waste from jackfruit wood extract, secang wood, mangsi fruit and several synthetic dyes, to identify potential environmental pollution.

Dyeing with natural dyes was performed by exhaust at room temperature by the pre-mordant method, while with synthetic dyes it was performed by exhaust according to the dyeing procedure (reactive, vat and naphthol). The groundwater, mordant solutions, natural dye extract and the waste-water from the natural and synthetic dyes were then tested to determine their biological oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids (TSS), pH, Al and heavy metal contents such as chromium (Cr), copper (Cu), cadmium (Cd), nickel (Ni), cobalt (Co) and lead (Pb).

Aluminium sulphate had the lowest pollution load while PAC had the highest, as aluminium sulphate had a higher BOD₅/COD ratio (0.62–0.67) than aluminium nitrate (0.56–0.64) or PAC (0.44–0.54). The dyeing waste from the three natural dyes contained an acidic pH of 3.5–4.2, Al of 75.280–621.34 mg/L, Cr of 0.154–0.215 mg/L and Cu of 0.035–0.072 mg/L. The values of TSS, COD and BOD₅ are higher than the quality standards of the waste but are environmentally friendly because the ratio of the BOD₅/COD values from the waste ranges from 0.44–0.67.

The findings indicate that as a mordant, aluminium sulphate results in lower pollution loads than aluminium nitrate and PAC. However, all three mordants contain Cr and Cu, albeit in negligible concentrations. Therefore, it is recommended that future studies strive to identify a mordant that has lower pollution loads and does not contain metals but can increase dyeing results to satisfy consumer requirements. It is the hope that, with the discovery of a new mordant, natural dyes will be the solution for the heavy metal pollution caused by synthetic dyes.

The use of environmentally-friendly mordants and natural dyes in the Indonesian textile and batik industry will give rise to superior quality eco-textile and eco-batik products. Such environmentally-friendly and high-quality products will not only increase competition and consumer interest but increase product sales as well which will, in turn, increase incomes and the economy. Additionally, an increase in the use of natural dyes by the textile and batik industry will serve as additional income to the communities and farmers from which the raw materials for the natural dyes are sourced thereby creating jobs and increasing welfare.

As environmentally-friendly mordants and natural dyes replace the hazardous and toxic materials currently used in the textile and batik industry, it guarantees the health and safety of its consumers and workers. Furthermore, as the waste-water produced is biodegradable, it reduces river and groundwater pollution. It is, therefore, expected that this information will not only lead to a shift in attitude within the textile and batik industries but the adoption of environmentally-friendly materials, for the sake of the environment, as well as the development of eco-textile and eco-batik products.

Aluminium sulphate is a mordant type of aluminium salt with a lower potential for contamination than aluminium nitrate and PAC. However, PAC has been discovered to be a mordant for natural dyes, as has the fruit of the mangsi shrub, which has recently been discovered as a naturally occurring blue dye.

A study was designed to investigate the chemical coagulation process for the treatment of the potato food industry wastewater of the “Chipsy factory” located at Abi‐Sier, Egypt. The chemical coagulants used in the study include alum, ferric chloride, calcium chloride, ferric sulphate and Nalco as polymer. Variable doses of these coagulants were examined to determine the optimum dose. Results obtained showed that chemical treatment (coagulation, flocculation, followed by sedimentation) was efficient to reduce the chemical oxygen demand (COD), total suspended solids (TSS) and turbidity significantly. Remarkable variation of the removal efficiency depends on the type of coagulant. Ferric chloride and ferric sulphate were more efficient than calcium chloride. Combination of Nalco with each of the studied coagulants improved the removal efficiency remarkably. Reduction of 91‐94 per cent of turbidity, 93‐97 per cent of COD, and 94‐97 per cent of the TSS was achieved with these combinations.

This study aims to use porous concrete and mineral adsorbents (additives) for reducing the quantity and improving the quality of urban runoff.

The effects of adding mineral adsorbents and fine grains to porous concrete is tested for increasing its performance in improving the quality of urban runoff. Two levels of sand (10 and 20 per cent) and 5, 10 and 15 per cent of zeolite, perlite, LECA and pumice were added to the porous concrete. Unconfined compressive strength, hydraulic conductivity (permeability) and porosity of the porous concrete specimens were measured. Some of the best specimens were selected for testing the improvement of runoff quality. A rainfall simulator was designed and the quality of the runoff was investigated for changes in electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS) and chemical oxygen demand (COD).

The results of this study showed that compressive strength of the porous concrete was increased by adding fine grains to the concrete mixture. Fine grains decreased the permeability and porosity of the samples. Zeolite had the highest compressive strength. Samples having pumice own maximum permeability. Samples which had perlite, had the least compressive strength and permeability. Because of the fast flow of runoff water in the porous slab and its low thickness, sufficient time was not provided for effective functioning of the additives, and the removal percentage of the pollution parameters was low.

Porous concrete can ameliorate both quantity and quality of the urban runoff.