 | This article's lead section may be too short to adequately summarize the key points.(September 2020) |
Thermal hydrolysis is a process used for treating industrial waste, municipal solid waste and sewage sludge.
| | This article's lead section may be too short to adequately summarize the key points.(September 2020) |
Thermal hydrolysis is a process used for treating industrial waste, municipal solid waste and sewage sludge.
Thermal hydrolysis is a two-stage process combining high-pressure boiling of waste or sludge followed by a rapid decompression. This combined action sterilizes the sludge and makes it more biodegradable, which improves digestion performance. Sterilization destroys pathogens in the sludge resulting in it exceeding the stringent requirements for land application (agriculture). [1]
In addition, the treatment adjusts the rheology to such an extent that loading rates to sludge anaerobic digesters can be doubled, and also dewaterability of the sludge is significantly improved. [2] [3] The first full-scale application of this process for sewage sludge was installed in Hamar, Norway in 1996. Since then, there have been over 30 additional installations globally. [1]
Sewage treatment plants, such as Blue Plains in Washington, D.C., USA, have adopted thermal hydrolysis of sewage sludge in order to produce commercially valuable products (such as electricity and high quality biosolid fertilizers) out of the wastewater. [4] The full-scale commercial application of thermal hydrolysis enables the plant to utilize the solids portion of the wastewater to make power and fine fertilizer directly from sewage waste. [5]
The city of Oslo, Norway installed a system for converting domestic food waste to fuel in 2012. A thermal hydrolysis system produces biogas from the food waste, which provides fuel for the city bus system and is also used for agricultural fertilizer. [6]
| Plant | Capacity (TDS/A)* | Commission Year | Thermal Hydrolysis Supplier |
|---|---|---|---|
| Blue Plains, Washington DC, USA | 135,000 | 2014 | Cambi |
| Gaoantun, Beijing, China | 134,000 | 2017 | Cambi |
| Gaobeidian, Beijing, China | 99,100 | 2016 | Cambi |
| Minworth, Birmingham, UK | 91,250 | 2018 | Cambi |
| Davyhulme, Manchester, UK | 91,000 | 2013 | Cambi |
| Huaifang, Beijing, China | 89,100 | 2017 | Cambi |
| Xiaohongmen, Beijing, China | 65,700 | 2016 | Cambi |
| Qinghe II, Beijing, China | 59,500 | 2017 | Cambi |
| Crossness, London, UK | 58,500 | 2018 | Cambi |
| Ringsend, Dublin, Ireland | 56,000 | 2002 | Cambi |
| Howdon, UK | 40,000 | 2010 | Cambi |
| Riverside, UK | 40,000 | 2009 | Cambi |
| Tees Valley, UK | 37,000 | 2008 | Cambi |
| Seafield, UK | 36,500 | 2015 | Cambi [7] |
| Beckton, UK | 36,500 | 2013 | Cambi |
| Cardiff, UK | 30,000 | 2009 | Cambi |
| Tilburg, Netherlands | 29,000 | 2014 | Cambi |
| Esholt, UK | 26,400 | 2013 | Veolia |
| Santiago, Chile | 25,000 | 2010 | Cambi |
| Oxford, UK | 24,400 | 2010 | Veolia |
| Vilnius, Lithuania | 23,000 | 2010 | Cambi |
| Whitlingham, UK | 23,000 | 2008 | Cambi |
| Vigo, Spain | 22,000 | 2014 | Cambi |
| Afan, UK | 20,000 | 2009 | Cambi |
| Bruxelles Nord, Belgium | 20,000 | 2007 | Cambi |
| Cotton Valley, Milton Keynes, UK | 20,000 | 2007 | Cambi |
| NOSES, Aberdeen, UK | 16,500 | 2001 | Cambi |
| Lille, France | 16,400 | 2013 | Veolia |
| EGE Waste Treatment, Oslo, Norway | 15,000 | 2012 | Cambi |
| Turku, Finland | 14,000 | 2009 | Cambi |
| Apeldoorn, Netherlands | 13,000 | 2015 | Sustec |
| Oxley Creek, Brisbane, Australia | 12,900 | 2006 | Cambi |
* Tons of Dry Solids/Year
Biogas is a gaseous renewable energy source produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste, wastewater, and food waste. Biogas is produced by anaerobic digestion with anaerobic organisms or methanogens inside an anaerobic digester, biodigester or a bioreactor. The gas composition is primarily methane and carbon dioxide and may have small amounts of hydrogen sulfide, moisture and siloxanes. The gases methane and hydrogen can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used in fuel cells and for heating purpose, such as in cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat.
Sewage sludge is the residual, semi-solid material that is produced as a by-product during sewage treatment of industrial or municipal wastewater. The term "septage" also refers to sludge from simple wastewater treatment but is connected to simple on-site sanitation systems, such as septic tanks.
Wastewater treatment is a process which removes and eliminates contaminants from wastewater and converts this into an effluent that can be returned to the water cycle. Once returned to the water cycle, the effluent creates an acceptable impact on the environment or is reused for various purposes. The treatment process takes place in a wastewater treatment plant. There are several kinds of wastewater which are treated at the appropriate type of wastewater treatment plant. For domestic wastewater, the treatment plant is called a Sewage Treatment. For industrial wastewater, treatment either takes place in a separate Industrial wastewater treatment, or in a sewage treatment plant. Further types of wastewater treatment plants include Agricultural wastewater treatment and leachate treatment plants.
Biosolids are solid organic matter recovered from a sewage treatment process and used as fertilizer. In the past, it was common for farmers to use animal manure to improve their soil fertility. In the 1920s, the farming community began also to use sewage sludge from local wastewater treatment plants. Scientific research over many years has confirmed that these biosolids contain similar nutrients to those in animal manures. Biosolids that are used as fertilizer in farming are usually treated to help to prevent disease-causing pathogens from spreading to the public. Some sewage sludge can not qualify as biosolids due to persistent, bioaccumulative and toxic chemicals, radionuclides, and heavy metals at levels sufficient to contaminate soil and water when applied to land.
The activated sludgeprocess is a type of biological wastewater treatment process for treating sewage or industrial wastewaters using aeration and a biological floc composed of bacteria and protozoa. It uses air and microorganisms to biologically oxidize organic pollutants, producing a waste sludge containing the oxidized material.
Anaerobic digestion is a sequence of processes by which microorganisms break down biodegradable material in the absence of oxygen. The process is used for industrial or domestic purposes to manage waste or to produce fuels. Much of the fermentation used industrially to produce food and drink products, as well as home fermentation, uses anaerobic digestion.
A garbage disposal unit (also known as a waste disposal unit, food waste disposer (FWD), in-sink macerator, garbage disposer, or garburator) is a device, usually electrically powered, installed under a kitchen sink between the sink's drain and the trap. The device shreds food waste into pieces small enough—generally less than 2 mm (0.079 in) in diameter—to pass through plumbing.
Milorganite is a brand of biosolids fertilizer produced by treating sewage sludge by the Milwaukee Metropolitan Sewerage District. The term is a portmanteau of the term Milwaukee Organic Nitrogen. The sewer system of the District collects municipal wastewater from the Milwaukee metropolitan area. After settling, wastewater is treated with microbes to break down organic matter at the Jones Island Water Reclamation Facility in Milwaukee, Wisconsin. The byproduct sewage sludge is produced. This is heat-dried with hot air in the range of 900–1,200 °F (482–649 °C), which heats the sewage sludge to at least 176 °F (80 °C) to kill pathogens. The material is then pelletized and marketed throughout the United States under the name Milorganite. The result is recycling of the nitrogen and phosphorus from the waste-stream as fertilizer. The treated wastewater is discharged to Lake Michigan.
The Hyperion Water Reclamation Plant is a sewage treatment plant in southwest Los Angeles, California, next to Dockweiler State Beach on Santa Monica Bay. The plant is the largest sewage treatment facility in the Los Angeles Metropolitan Area and one of the largest plants in the world. Hyperion is operated by the City of Los Angeles, Department of Public Works, and the Bureau of Sanitation. Hyperion is the largest sewage plant by volume west of the Mississippi River.
Sewage sludge treatment describes the processes used to manage and dispose of sewage sludge produced during sewage treatment. Sludge treatment is focused on reducing sludge weight and volume to reduce transportation and disposal costs, and on reducing potential health risks of disposal options. Water removal is the primary means of weight and volume reduction, while pathogen destruction is frequently accomplished through heating during thermophilic digestion, composting, or incineration. The choice of a sludge treatment method depends on the volume of sludge generated, and comparison of treatment costs required for available disposal options. Air-drying and composting may be attractive to rural communities, while limited land availability may make aerobic digestion and mechanical dewatering preferable for cities, and economies of scale may encourage energy recovery alternatives in metropolitan areas.
Aerobic digestion is a process in sewage treatment designed to reduce the volume of sewage sludge and make it suitable for subsequent use. More recently, technology has been developed that allows the treatment and reduction of other organic waste, such as food, cardboard and horticultural waste. It is a bacterial process occurring in the presence of oxygen. Bacteria rapidly consume organic matter and convert it into carbon dioxide, water and a range of lower molecular weight organic compounds. As there is no new supply of organic material from sewage, the activated sludge biota begin to die and are used as food by saprotrophic bacteria. This stage of the process is known as endogenous respiration and it is process that reduces the solid concentration in the sludge.
Sewage treatment is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water pollution from raw sewage discharges. Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. There are a high number of sewage treatment processes to choose from. These can range from decentralized systems to large centralized systems involving a network of pipes and pump stations which convey the sewage to a treatment plant. For cities that have a combined sewer, the sewers will also carry urban runoff (stormwater) to the sewage treatment plant. Sewage treatment often involves two main stages, called primary and secondary treatment, while advanced treatment also incorporates a tertiary treatment stage with polishing processes and nutrient removal. Secondary treatment can reduce organic matter from sewage, using aerobic or anaerobic biological processes.
Blue Plains Advanced Wastewater Treatment Plant in Washington, D.C., is the largest advanced wastewater treatment plant in the world. The facility is operated by the District of Columbia Water and Sewer Authority. The plant opened in 1937 as a primary treatment facility, and advanced treatment capacity was added in the 1970s and 1980s. The effluent that leaves Blue Plains is discharged to the Potomac River and meets some of the most stringent permit limits in the United States.
Lystek International is a Canadian waste treatment technology company founded in 2000 at the University of Waterloo, Ontario, Canada to commercialize treatment technologies for biosolids and other non-hazardous, organic waste materials. Lystek is headquartered in Cambridge, Ontario, Canada and is owned by its management and R.W. Tomlinson Ltd.
Reuse of human excreta is the safe, beneficial use of treated human excreta after applying suitable treatment steps and risk management approaches that are customized for the intended reuse application. Beneficial uses of the treated excreta may focus on using the plant-available nutrients that are contained in the treated excreta. They may also make use of the organic matter and energy contained in the excreta. To a lesser extent, reuse of the excreta's water content might also take place, although this is better known as water reclamation from municipal wastewater. The intended reuse applications for the nutrient content may include: soil conditioner or fertilizer in agriculture or horticultural activities. Other reuse applications, which focus more on the organic matter content of the excreta, include use as a fuel source or as an energy source in the form of biogas.
Fecal sludge management (FSM) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal sludge constitute the "value chain" or "service chain" of fecal sludge management. Fecal sludge is defined very broadly as what accumulates in onsite sanitation systems and specifically is not transported through a sewer. It is composed of human excreta, but also anything else that may go into an onsite containment technology, such as flushwater, cleansing materials, menstrual hygiene products, grey water, and solid waste. Fecal sludge that is removed from septic tanks is called septage.
The Thomas P. Smith Water Reclamation Facility (TPSWRF) is owned and operated by the city of Tallahassee, Florida. The facility provides sewage treatment services for Tallahassee, Florida and the surrounding areas.
Anthroponics is a type of hydroponics system that uses human waste like urine as the source of nutrients for the cultivated plants. In general, the human urine or mixed waste is collected and stored for a period of time, before being applied either directly or passed through a biofilter before reaching the plants. As a form of organic hydroponics, anthroponics combines elements of both hydroponics and aquaponics systems.
Huaifang Water Reclamation Plant is a wastewater recycling plant, located in the southwest of Beijing, China. Commissioning since 2017, the 3-floor plant is spanned over an area of 162,000 m2 which is built in response to the state capital of Beijing, facing a water shortage challenge exacerbated by climate change and urbanization with having the major water treatment systems being installed underground to save a valuable land. The water treatment project is said to have been equipped with the forefront technologies.
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