thumb|Thermal Hydrolysis Plant in Cardiff, Wales, UK '''Thermal hydrolysis''' is a process used for treating industrial waste, municipal solid waste and sewage sludge by applying heat and rapid lowering of pressure. It is used to sterilize the waste stream and produce fertilizer, biogas, and other useful products. It was first deployed in 1996.
==Description== 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).<ref name=WaterWorld>{{cite journal |last1=Barber |first1=Bill |last2=Lancaster |first2=Rick |last3=Kleiven |first3=Harald |title=Thermal Hydrolysis: The Missing Ingredient for Better Biosolids? |url=http://www.waterworld.com/articles/wwi/print/volume-27/issue-4/editorial-focus/slidge-processing-biosolids/thermal-hydrolysis-the-missing-ingredient.html |journal=Water World |volume=27 |issue=4 |date=2012-09-01 |access-date=2014-05-24 |archive-date=2016-10-14 |archive-url=https://web.archive.org/web/20161014020522/http://www.waterworld.com/articles/wwi/print/volume-27/issue-4/editorial-focus/slidge-processing-biosolids/thermal-hydrolysis-the-missing-ingredient.html |url-status=live }}</ref>
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.<ref name=JHazMat>{{cite journal |last1=Neyens |first1=Elisabeth |last2=Baeyens |first2=Jan |title=A review of thermal sludge pre-treatment processes to improve dewaterability |journal=Journal of Hazardous Materials |volume=B98|issue=1–3 |pages=51–57 |date=2003 |doi=10.1016/S0304-3894(02)00320-5|pmid=12628777 |bibcode=2003JHzM...98...51N }}</ref><ref name=WaterResearch>{{cite journal |last1=Skinner |first1=Samuel |last2=Studer |first2=Lindsay |last3=Dixon |first3=David |last4=Hillis |first4=Peter |last5=Rees |first5=Catherine |last6=Wall |first6=Rachael |last7=Cavalida |first7=Raul |last8=Usher |first8=Shane |last9=Stickland |first9=Anthony |last10=Scales |first10=Peter |title=Quantification of wastewater sludge dewatering |url=https://www.researchgate.net/publication/277133349 |journal=Water Research |volume=82 |pages=2–13 |date=2015 |access-date=2017-02-23 |doi=10.1016/j.watres.2015.04.045 |pmid=26003332 |archive-date=2021-10-09 |archive-url=https://web.archive.org/web/20211009203511/https://www.researchgate.net/publication/277133349_Quantification_of_wastewater_sludge_dewatering |url-status=live |doi-access=free |bibcode=2015WatRe..82....2S }}</ref> 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.<ref name=WaterWorld/>
thumb|Thermal hydrolysis reactors at Blue Plains in 2016.
== Commercial application at a sewage treatment plant == 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.<ref name="DC Water">{{cite news |last=Halsey |first=Ashley |date=2014-04-05 |title=DC Water adopts Norway's Cambi system for making power and fine fertilizer from sewage |url=https://www.washingtonpost.com/local/trafficandcommuting/dc-water-adopts-norways-cambi-system-for-turning-sewage-into-electricity-and-fertilizer/2014/04/05/3d456d7e-a642-11e3-9cff-b1406de784f0_story.html |newspaper=The Washington Post |access-date=2014-05-24 |archive-date=2014-04-12 |archive-url=https://web.archive.org/web/20140412231537/http://www.washingtonpost.com/local/trafficandcommuting/dc-water-adopts-norways-cambi-system-for-turning-sewage-into-electricity-and-fertilizer/2014/04/05/3d456d7e-a642-11e3-9cff-b1406de784f0_story.html |url-status=live }}</ref> 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.<ref name="From toilet to turbine">{{cite news |last1=Berkowitz |first1=Bonnie |last2=Lindeman |first2=Todd |date=2014-04-05 |title=From Toilet to Turbine |url=https://www.washingtonpost.com/local/trafficandcommuting/from-toilet-to-turbine/2014/04/05/9dc0e49e-bd26-11e3-bcec-b71ee10e9bc3_graphic.html |newspaper=The Washington Post |access-date=2014-05-24 |archive-date=2016-03-13 |archive-url=https://web.archive.org/web/20160313071007/https://www.washingtonpost.com/local/trafficandcommuting/from-toilet-to-turbine/2014/04/05/9dc0e49e-bd26-11e3-bcec-b71ee10e9bc3_graphic.html |url-status=live }}</ref>
==Municipal waste-to-fuel application== 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.<ref name="Oslo Biogas">{{cite press release |url=http://ens-newswire.com/2012/03/23/food-waste-to-fuel-oslos-city-buses/ |title=Food Waste to Fuel Oslo's City Buses |author=<!--Staff writer(s); no by-line.--> |date=2012-03-23 |website=Environment News Service |publisher= |location=Lincoln City, OR |access-date=2014-05-24 |archive-date=2014-07-09 |archive-url=https://web.archive.org/web/20140709002913/http://ens-newswire.com/2012/03/23/food-waste-to-fuel-oslos-city-buses/ |url-status=live }}</ref>
== 30 largest thermal hydrolysis plants == {| class="wikitable" ! scope="col" | Plant ! scope="col" | Capacity<br />{{Small|(TDS/A)<nowiki>*</nowiki>}} ! scope="col" | Commission<br />Year ! scope="col" | Thermal Hydrolysis<br />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, Newcastle Upon Tyne, UK || 40,000 || 2010 || Cambi |- | Riverside, London, UK || 40,000 || 2009 || Cambi |- | Tees Valley, UK || 37,000 || 2008 || Cambi |- | Seafield, Edinburgh UK || 36,500 || 2015 || Cambi<ref>https://www.cambi.com/references/plants/europe/united-kingdom/edinburgh-seafield/ {{Dead link|date=February 2022}}</ref> |- | Beckton, London, UK || 36,500 || 2013 || Cambi |- | Cardiff, UK || 30,000 || 2009 || Cambi |- | Tilburg, Netherlands || 29,000 || 2014 || Cambi |- | Esholt, Yorkshire, UK || 26,400 || 2013 || Veolia |- | Santiago, Chile || 25,000 || 2010 || Cambi |- | Oxford, UK || 24,400 || 2010 || Veolia |- | Vilnius, Lithuania || 23,000 || 2010 || Cambi |- | Whitlingham, Norwich, 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 |[https://www.sustec.com Sustec] |- | Oxley Creek, Brisbane, Australia || 12,900 || 2006 || Cambi |} {{Small|<nowiki>*</nowiki> Tons of Dry Solids/Year}}
==See also== * List of waste-water treatment technologies
== References == {{Reflist}}
==Further reading== {{Refbegin}} * {{cite web |last1=Kline |first1=Michele |last2=Gurieff |first2=Nicholas |last3=Bruus |first3=Jacob |date=2011-04-01 |title=Thermal Hydrolysis System Helps Increase Biogas Production |url=http://www.waterworld.com/articles/2011/04/thermal-hydrolysis-system-helps-increase-biogas-production.html |website=Water World |publisher=PennWell Publishing |access-date=24 May 2014}} {{Refend}}
==External links== *{{Commons category-inline}}
Category:Biodegradable waste management Category:Biofuels technology Category:Chemical reactions Category:Equilibrium chemistry Category:Sewerage