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53-554: Cacia pulp and paper mill effluent , one of the major polluting sources of the Vouga River and Aveiro Lagoon , is discharged into the Aveiro coastal area. The area has an unpleasant smell due to the effluent. 40°40′59″N 8°40′01″W  /  40.683°N 8.667°W  / 40.683; -8.667 This Viseu location article is a stub . You can help Misplaced Pages by expanding it . This Aveiro location article

106-435: A CWT plant, rather than perform treatment on site, due to constraints such as limited land availability, difficulty in designing and operating an on-site system, or limitations imposed by environmental regulations and permits. A manufacturer may determine that using a CWT is more cost-effective than treating the waste itself; this is often the case where the manufacturer is a small business. CWT plants often receive wastes from

159-435: A lot of waste-waters such as paper and pulp production have created environmental concern, leading to development of processes to recycle water use within plants before they have to be cleaned and disposed. An industrial wastewater treatment plant may include one or more of the following rather than the conventional treatment sequence of sewage treatment plants: Brine treatment involves removing dissolved salt ions from

212-602: A lubricant and coolant. Contaminants include hydraulic oils , tallow and particulate solids. Final treatment of iron and steel products before onward sale into manufacturing includes pickling in strong mineral acid to remove rust and prepare the surface for tin or chromium plating or for other surface treatments such as galvanisation or painting . The two acids commonly used are hydrochloric acid and sulfuric acid . Wastewater include acidic rinse waters together with waste acid. Although many plants operate acid recovery plants (particularly those using hydrochloric acid), where

265-445: A major source of industrial wastewater. Many of these plants discharge wastewater with significant levels of metals such as lead , mercury , cadmium and chromium , as well as arsenic , selenium and nitrogen compounds ( nitrates and nitrites ). Wastewater streams include flue-gas desulfurization , fly ash , bottom ash and flue gas mercury control. Plants with air pollution controls such as wet scrubbers typically transfer

318-817: A particular problem in treating waters generated in wool processing. Animal fats may be present in the wastewater, which if not contaminated, can be recovered for the production of tallow or further rendering. Textile dyeing plants generate wastewater that contain synthetic (e.g., reactive dyes, acid dyes, basic dyes, disperse dyes, vat dyes, sulphur dyes, mordant dyes, direct dyes, ingrain dyes, solvent dyes, pigment dyes) and natural dyestuff, gum thickener (guar) and various wetting agents, pH buffers and dye retardants or accelerators. Following treatment with polymer-based flocculants and settling agents, typical monitoring parameters include BOD, COD, color (ADMI), sulfide, oil and grease, phenol, TSS and heavy metals (chromium, zinc , lead, copper). Industrial applications where oil enters

371-1156: A pre-treatment system to remove some pollutants (e.g., toxic compounds), and then discharge the partially treated wastewater to the municipal sewer system. Most industries produce some wastewater . Recent trends have been to minimize such production or to recycle treated wastewater within the production process. Some industries have been successful at redesigning their manufacturing processes to reduce or eliminate pollutants. Sources of industrial wastewater include battery manufacturing, chemical manufacturing, electric power plants, food industry , iron and steel industry, metal working, mines and quarries, nuclear industry, oil and gas extraction , petroleum refining and petrochemicals , pharmaceutical manufacturing, pulp and paper industry , smelters, textile mills , industrial oil contamination , water treatment and wood preserving . Treatment processes include brine treatment, solids removal (e.g. chemical precipitation, filtration), oils and grease removal, removal of biodegradable organics, removal of other organics, removal of acids and alkalis, and removal of toxic materials. Industrial facilities may generate

424-467: A sewage treatment plant (usually after some form of pre-treatment). Other types of wastewater treatment plants include agricultural wastewater treatment and leachate treatment plants. Treating wastewater efficiently is challenging, but improved technology allows for enhanced removal of specific materials, increased re-use of water , and energy production from waste. In the United States,

477-412: A wastewater rich in hardness ions which are readily precipitated out, especially when in admixture with other wastewater constituents. Wood preserving plants generate conventional and toxic pollutants, including arsenic, COD, copper, chromium, abnormally high or low pH, phenols, suspended solids, oil and grease. The various types of contamination of wastewater require a variety of strategies to remove

530-442: A wide range of manufacturing industries, mining industries, oil and gas extraction, and service industries. There are several kinds of wastewater which are treated at the appropriate type of treatment plant. Domestic wastewater (also called municipal wastewater or sewage ) is processed at a sewage treatment plant . For industrial wastewater, treatment either takes place in a separate industrial wastewater treatment facility, or in

583-562: A wide variety of manufacturers, including chemical plants, metal fabrication and finishing; and used oil and petroleum products from various manufacturing sectors. The wastes may be classified as hazardous , have high pollutant concentrations or otherwise be difficult to treat. In 2000 the U.S. Environmental Protection Agency published wastewater regulations for CWT facilities in the US. The specific pollutants discharged by organic chemical manufacturers vary widely from plant to plant, depending on

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636-508: Is a stub . You can help Misplaced Pages by expanding it . This article related to a river in Portugal is a stub . You can help Misplaced Pages by expanding it . Effluent Effluent is wastewater from sewers or industrial outfalls that flows directly into surface waters , either untreated or after being treated at a facility. The term has slightly different meanings in certain contexts, and may contain various pollutants depending on

689-408: Is released to surface water. Wastewater percolated or injected into groundwater may not be described as effluent if soil is assumed to perform treatment by filtration or ion exchange ; although concealed flow through fractured bedrock , lava tubes , limestone caves , or gravel in ancient stream channels may allow relatively untreated wastewater to emerge as springs . Effluent in

742-494: Is similar for other highly scaling industrial wastewaters. Wastewater generated from agricultural and food processing operations has distinctive characteristics that set it apart from common municipal wastewater managed by public or private sewage treatment plants throughout the world: it is biodegradable and non-toxic, but has high Biological Oxygen Demand (BOD) and suspended solids (SS). The constituents of food and agriculture wastewater are often complex to predict, due to

795-565: Is then used to feed the bacteria in biofilters . In the context of a thermal power station and other industrial facilities, the output of the cooling system may be referred to as the effluent cooling water, which is noticeably warmer than the environment and is called thermal pollution . In chemical engineering practice, effluent is the stream exiting a chemical reactor . Effluent may carry pollutants such as fats, oils and greases; solvents, detergents and other chemicals; heavy metal; other solids; and food waste. Possible sources include

848-789: Is used as a regulatory parameter in some discharge permits. Metal pollutant discharges may include chromium , copper , lead , nickel and zinc . The inorganic chemicals sector covers a wide variety of products and processes, although an individual plant may produce a narrow range of products and pollutants. Products include aluminum compounds; calcium carbide and calcium chloride; hydrofluoric acid; potassium compounds; borax; chrome and fluorine-based compounds; cadmium and zinc-based compounds. The pollutants discharged vary by product sector and individual plant, and may include arsenic, chlorine, cyanide, fluoride; and heavy metals such as chromium, copper, iron, lead, mercury, nickel and zinc. Fossil-fuel power stations , particularly coal -fired plants, are

901-602: The Clean Water Act requires all direct effluent discharges to surface waters to be regulated with permits under the National Pollutant Discharge Elimination System (NPDES). Indirect dischargers–facilities which send their wastewater to municipal sewage treatment plants–may be subject to pretreatment requirements. NPDES permits require discharging facilities to limit or treat effluent to the levels that result from using

954-851: The pulp and paper industry is generally high in suspended solids and BOD. Plants that bleach wood pulp for paper making may generate chloroform , dioxins (including 2,3,7,8-TCDD ), furans , phenols and chemical oxygen demand (COD). Stand-alone paper mills using imported pulp may only require simple primary treatment, such as sedimentation or dissolved air flotation . Increased BOD or COD loadings, as well as organic pollutants, may require biological treatment such as activated sludge or upflow anaerobic sludge blanket reactors . For mills with high inorganic loadings like salt, tertiary treatments may be required, either general membrane treatments like ultrafiltration or reverse osmosis or treatments to remove specific contaminants, such as nutrients. The pollutants discharged by nonferrous smelters vary with

1007-434: The artificial sense is in general considered to be water pollution , such as the outflow from a sewage treatment facility or an industrial wastewater discharge. An effluent sump pump , for instance, pumps waste from toilets installed below a main sewage line. In the context of waste water treatment plants , effluent that has been treated is sometimes called secondary effluent , or treated effluent . This cleaner effluent

1060-533: The base metal ore. Bauxite smelters generate phenols but typically use settling basins and evaporation to manage these wastes, with no need to routinely discharge wastewater. Aluminum smelters typically discharge fluoride , benzo(a)pyrene , antimony and nickel , as well as aluminum. Copper smelters typically generate cadmium , lead, zinc, arsenic and nickel, in addition to copper, in their wastewater. Lead smelters discharge lead and zinc. Nickel and cobalt smelters discharge ammonia and copper in addition to

1113-628: The base metals. Zinc smelters discharge arsenic, cadmium, copper, lead, selenium and zinc. Typical treatment processes used in the industry are chemical precipitation, sedimentation and filtration. Textile mills , including carpet manufacturers, generate wastewater from a wide variety of processes, including cleaning and finishing, yarn manufacturing and fabric finishing (such as bleaching , dyeing , resin treatment, waterproofing and retardant flameproofing ). Pollutants generated by textile mills include BOD, SS, oil and grease, sulfide, phenols and chromium. Insecticide residues in fleeces are

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1166-632: The bioaccumulation of strontium by Scenedesmus spinosus ( algae ) in simulated wastewater. The study claims a highly selective biosorption capacity for strontium of S. spinosus, suggesting that it may be appropriate for use of nuclear wastewater. Oil and gas well operations generate produced water , which may contain oils, toxic metals (e.g. arsenic , cadmium , chromium , mercury, lead), salts, organic chemicals and solids. Some produced water contains traces of naturally occurring radioactive material . Offshore oil and gas platforms also generate deck drainage, domestic waste and sanitary waste. During

1219-416: The captured pollutants to the wastewater stream. Ash ponds , a type of surface impoundment, are a widely used treatment technology at coal-fired plants. These ponds use gravity to settle out large particulates (measured as total suspended solids ) from power plant wastewater. This technology does not treat dissolved pollutants. Power stations use additional technologies to control pollutants, depending on

1272-511: The contamination. Most industrial processes, such as petroleum refineries , chemical and petrochemical plants have onsite facilities to treat their wastewaters so that the pollutant concentrations in the treated wastewater comply with the regulations regarding disposal of wastewaters into sewers or into rivers, lakes or oceans. Constructed wetlands are being used in an increasing number of cases as they provided high quality and productive on-site treatment. Other industrial processes that produce

1325-642: The differences in BOD and pH in effluents from vegetable, fruit, and meat products and due to the seasonal nature of food processing and post-harvesting. Processing of food from raw materials requires large volumes of high grade water. Vegetable washing generates water with high loads of particulate matter and some dissolved organic matter . It may also contain surfactants and pesticides. Aquaculture facilities (fish farms) often discharge large amounts of nitrogen and phosphorus, as well as suspended solids. Some facilities use drugs and pesticides, which may be present in

1378-644: The disposal of FOG in the sewer system. Food processing activities such as plant cleaning, material conveying, bottling, and product washing create wastewater. Many food processing facilities require on-site treatment before operational wastewater can be land applied or discharged to a waterway or a sewer system. High suspended solids levels of organic particles increase BOD and can result in significant sewer surcharge fees. Sedimentation, wedge wire screening, or rotating belt filtration (microscreening) are commonly used methods to reduce suspended organic solids loading prior to discharge. Glass manufacturing wastes vary with

1431-671: The drilling process, well sites typically discharge drill cuttings and drilling mud (drilling fluid). Pollutants discharged at petroleum refineries and petrochemical plants include conventional pollutants (BOD, oil and grease, suspended solids ), ammonia, chromium, phenols and sulfides. Pharmaceutical plants typically generate a variety of process wastewaters, including solvents, spent acid and caustic solutions, water from chemical reactions, product wash water, condensed steam, blowdown from air pollution control scrubbers, and equipment washwater. Non-process wastewaters typically include cooling water and site runoff. Pollutants generated by

1484-457: The ever increasing discharge standards, there has been an emergence of the use of advance oxidation processes for the treatment of brine. Some notable examples such as Fenton's oxidation and ozonation have been employed for degradation of recalcitrant compounds in brine from industrial plants. Reverse osmosis may not be viable for brine treatment, due to the potential for fouling caused by hardness salts or organic contaminants, or damage to

1537-408: The exposure to air and water that inevitably occurs when the tailings are disposed of in large impoundments. The resulting acid mine drainage , which is often rich in heavy metals (because acids dissolve metals), is one of the many environmental impacts of mining . The waste production from the nuclear and radio-chemicals industry is dealt with as Radioactive waste . Researchers have looked at

1590-857: The following industrial wastewater flows: Industrial wastewater could add the following pollutants to receiving water bodies if the wastewater is not treated and managed properly: The specific pollutants generated and the resultant effluent concentrations can vary widely among the industrial sectors. Battery manufacturers specialize in fabricating small devices for electronics and portable equipment (e.g., power tools), or larger, high-powered units for cars, trucks and other motorized vehicles. Pollutants generated at manufacturing plants includes cadmium, chromium, cobalt, copper, cyanide, iron, lead, manganese, mercury, nickel, silver, zinc, oil and grease. A centralized waste treatment (CWT) facility processes liquid or solid industrial wastes generated by off-site manufacturing facilities. A manufacturer may send its wastes to

1643-433: The geologic formations that harbour economically valuable metals such as copper and gold very often consist of sulphide-type ores. The processing entails grinding the rock into fine particles and then extracting the desired metal(s), with the leftover rock being known as tailings. These tailings contain a combination of not only undesirable leftover metals, but also sulphide components which eventually form sulphuric acid upon

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1696-409: The industry include acetone , ammonia, benzene, BOD, chloroform, cyanide, ethanol , ethyl acetate , isopropanol , methylene chloride , methanol , phenol and toluene. Treatment technologies used include advanced biological treatment (e.g. activated sludge with nitrification), multimedia filtration , cyanide destruction (e.g. hydrolysis ), steam stripping and wastewater recycling. Effluent from

1749-1751: The mineral acid is boiled away from the iron salts, there remains a large volume of highly acid ferrous sulfate or ferrous chloride to be disposed of. Many steel industry wastewaters are contaminated by hydraulic oil, also known as soluble oil. Many industries perform work on metal feedstocks (e.g. sheet metal, ingots ) as they fabricate their final products. The industries include automobile, truck and aircraft manufacturing; tools and hardware manufacturing; electronic equipment and office machines; ships and boats; appliances and other household products; and stationary industrial equipment (e.g. compressors, pumps, boilers). Typical processes conducted at these plants include grinding , machining , coating and painting, chemical etching and milling , solvent degreasing , electroplating and anodizing . Wastewater generated from these industries may contain heavy metals (common heavy metal pollutants from these industries include cadmium, chromium, copper, lead, nickel, silver and zinc), cyanide and various chemical solvents, oil, and grease. The principal waste-waters associated with mines and quarries are slurries of rock particles in water. These arise from rainfall washing exposed surfaces and haul roads and also from rock washing and grading processes. Volumes of water can be very high, especially rainfall related arisings on large sites. Some specialized separation operations, such as coal washing to separate coal from native rock using density gradients , can produce wastewater contaminated by fine particulate haematite and surfactants . Oils and hydraulic oils are also common contaminants. Wastewater from metal mines and ore recovery plants are inevitably contaminated by

1802-476: The minerals present in the native rock formations. Following crushing and extraction of the desirable materials, undesirable materials may enter the wastewater stream. For metal mines, this can include unwanted metals such as zinc and other materials such as arsenic . Extraction of high value metals such as gold and silver may generate slimes containing very fine particles in where physical removal of contaminants becomes particularly difficult. Additionally,

1855-436: The most effective treatment technologies possible at a practical cost to mitigate the effects of discharges on the receiving waters. EPA has published technology-based regulations, called " effluent guidelines ", for 59 industrial categories.  The agency reviews the standards annually, conducts research on various categories, and makes revisions as appropriate. Noncompliance with these standards and all other conditions in

1908-472: The particular wastestream in the plant. These include dry ash handling, closed-loop ash recycling, chemical precipitation , biological treatment (such as an activated sludge process), membrane systems, and evaporation-crystallization systems. Technological advancements in ion-exchange membranes and electrodialysis systems has enabled high efficiency treatment of flue-gas desulfurization wastewater to meet recent EPA discharge limits. The treatment approach

1961-401: The permit authority must set conditions in the permit that prohibit dilution. The U.S. "Secondary Treatment Regulation" is the national standard for municipal sewage treatment plants. Industrial wastewater treatment Industrial wastewater treatment describes the processes used for treating wastewater that is produced by industries as an undesirable by-product. After treatment,

2014-445: The permits is punishable by law. Each year, effluent guidelines regulations prevent billions of pounds of contaminants from being released into bodies of water. EPA regulations require effluent limitations to be expressed as mass-based limits (rather than concentration-based limits) in the permits, so that discharging facilities will not use dilution as a substitute for treatment. In cases where setting mass-based limits are infeasible,

2067-410: The pollutant concentrations in the treated wastewater comply with the regulations regarding disposal of wastewaters into sewers or into rivers, lakes or oceans . This applies to industries that generate wastewater with high concentrations of organic matter (e.g. oil and grease), toxic pollutants (e.g. heavy metals, volatile organic compounds ) or nutrients such as ammonia . Some industries install

2120-576: The prime mover is concentrated salt water. As a result, evaporation systems typically employ titanium or duplex stainless steel materials. Brine management examines the broader context of brine treatment and may include consideration of government policy and regulations, corporate sustainability , environmental impact, recycling, handling and transport, containment, centralized compared to on-site treatment, avoidance and reduction, technologies, and economics. Brine management shares some issues with leachate management and more general waste management . In

2173-468: The recent years, there has been greater prevalence in brine management due to global push for zero liquid discharge (ZLD)/minimal liquid discharge (MLD). In ZLD/MLD techniques, a closed water cycle is used to minimize water discharges from a system for water reuse . This concept has been gaining traction in recent years, due to increased water discharges and recent advancement in membrane technology. Increasingly, there has been also greater efforts to increase

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2226-882: The recovery of fresh water or salts. Brine treatment systems may also be optimized to reduce electricity consumption, chemical usage, or physical footprint. Brine treatment is commonly encountered when treating cooling tower blowdown, produced water from steam-assisted gravity drainage (SAGD), produced water from natural gas extraction such as coal seam gas , frac flowback water, acid mine or acid rock drainage , reverse osmosis reject, chlor-alkali wastewater, pulp and paper mill effluent, and waste streams from food and beverage processing. Brine treatment technologies may include: membrane filtration processes, such as reverse osmosis ; ion-exchange processes such as electrodialysis or weak acid cation exchange ; or evaporation processes, such as brine concentrators and crystallizers employing mechanical vapour recompression and steam. Due to

2279-516: The recovery of materials from brines, especially from mining, geothermal wastewater or desalination brines. Various literature demosntrates the vaibility of extraction of valuable materials like sodium bicarbonates, sodium chlorides and precious metals (like rubidium, cesium and lithium). The concept of ZLD/MLD encompasses the downstream management of wastewater brines, to reduce discharges and also derive valuable products from it. Most solids can be removed using simple sedimentation techniques with

2332-425: The reverse osmosis membranes from hydrocarbons . Evaporation processes are the most widespread for brine treatment as they enable the highest degree of concentration, as high as solid salt. They also produce the highest purity effluent, even distillate-quality. Evaporation processes are also more tolerant of organics, hydrocarbons, or hardness salts. However, energy consumption is high and corrosion may be an issue as

2385-534: The solids recovered as slurry or sludge. Very fine solids and solids with densities close to the density of water pose special problems. In such case filtration or ultrafiltration may be required. Although flocculation may be used, using alum salts or the addition of polyelectrolytes . Wastewater from industrial food processing often requires on-site treatment before it can be discharged to prevent or reduce sewer surcharge fees. The type of industry and specific operational practices determine what types of wastewater

2438-587: The source. Effluent is defined by the United States Environmental Protection Agency (EPA) as "wastewater–treated or untreated–that flows out of a treatment plant, sewer, or industrial outfall. Generally refers to wastes discharged into surface waters". The Compact Oxford English Dictionary defines effluent as "liquid waste or sewage discharged into a river or the sea". Wastewater is not usually described as effluent while being recycled , re-used, or treated until it

2491-404: The treated industrial wastewater (or effluent) may be reused or released to a sanitary sewer or to a surface water in the environment. Some industrial facilities generate wastewater that can be treated in sewage treatment plants . Most industrial processes, such as petroleum refineries , chemical and petrochemical plants have their own specialized facilities to treat their wastewaters so that

2544-626: The type of glass manufactured, which includes fiberglass , plate glass , rolled glass , and glass containers, among others. The wastewater discharged by glass plants may include ammonia, BOD, chemical oxygen demand (COD), fluoride , lead, oil, phenol, and/or phosphorus. The discharges may also be highly acidic (low pH) or alkaline (high pH). The production of iron from its ores involves powerful reduction reactions in blast furnaces. Cooling waters are inevitably contaminated with products especially ammonia and cyanide . Production of coke from coal in coking plants also requires water cooling and

2597-444: The types of products manufactured, such as bulk organic chemicals, resins, pesticides, plastics, or synthetic fibers. Some of the organic compounds that may be discharged are benzene , chloroform , naphthalene , phenols , toluene and vinyl chloride . Biochemical oxygen demand (BOD), which is a gross measurement of a range of organic pollutants, may be used to gauge the effectiveness of a biological wastewater treatment system, and

2650-459: The use of water in by-products separation. Contamination of waste streams includes gasification products such as benzene , naphthalene , anthracene , cyanide, ammonia, phenols , cresols together with a range of more complex organic compounds known collectively as polycyclic aromatic hydrocarbons (PAH). The conversion of iron or steel into sheet, wire or rods requires hot and cold mechanical transformation stages frequently employing water as

2703-442: The waste stream. Although similarities to seawater or brackish water desalination exist, industrial brine treatment may contain unique combinations of dissolved ions, such as hardness ions or other metals, necessitating specific processes and equipment. Brine treatment systems are typically optimized to either reduce the volume of the final discharge for more economic disposal (as disposal costs are often based on volume) or maximize

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2756-908: The wastewater stream may include vehicle wash bays, workshops, fuel storage depots, transport hubs and power generation. Often the wastewater is discharged into local sewer or trade waste systems and must meet local environmental specifications. Typical contaminants can include solvents, detergents, grit, lubricants and hydrocarbons. Many industries have a need to treat water to obtain very high quality water for their processes. This might include pure chemical synthesis or boiler feed water. Also, some water treatment processes produce organic and mineral sludges from filtration and sedimentation which require treatment. Ion exchange using natural or synthetic resins removes calcium , magnesium and carbonate ions from water, typically replacing them with sodium , chloride , hydroxyl and/or other ions. Regeneration of ion-exchange columns with strong acids and alkalis produces

2809-756: The wastewater. Dairy processing plants generate conventional pollutants (BOD, SS). Animal slaughter and processing produces organic waste from body fluids, such as blood , and gut contents. Pollutants generated include BOD, SS, coliform bacteria , oil and grease, organic nitrogen and ammonia . Processing food for sale produces wastes generated from cooking which are often rich in plant organic material and may also contain salt , flavourings , colouring material and acids or alkali . Large quantities of fats, oil and grease ("FOG") may also be present, which in sufficient concentrations can clog sewer lines. Some municipalities require restaurants and food processing businesses to use grease interceptors and regulate

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