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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Propostas de procedimentos para o estabelecimento de metas de qualidade do serviço de distribuição de energia elétrica. / Proposals of procedures for setting targets for power distribution service quality.

González Pérez, Jenny Paola 06 March 2012 (has links)
Este trabalho apresenta uma análise crítica da metodologia usada no PRODIST 2010, e propostas alternativas para a fixação de metas e tarifas em função da qualidade do serviço. Todas as análises se sustentam em estudos estatísticos dos dados de interrupções nos anos 2007 e 2008 de 6 empresas distribuidoras de energia com diferentes características de DEC, FEC, número de usuários e número de conjuntos. A primeira proposta chamada de Tarifa Única Meta Única (TAMU) propõe a mesma meta de qualidade do serviço para todos os usuários de um mesmo nível de tensão. Na proposta se fixou como critério geral que 10% dos usuários pior atendidos de um nível de tensão devem ser ressarcidos por má qualidade do serviço. Para alcançar esse objetivo as metas dos níveis de tensão de cada empresa foram fixadas a partir dos seus histogramas de frequência acumulada dos indicadores individuais dos usuários. Esse procedimento garante que a percentagem de usuários ressarcidos seja igual em todos os níveis de tensão das empresas. Os resultados obtidos no cálculo da multa média por usuário ressarcido conservam uma coerência justa com a piora dos indicadores coletivos (isto não acontece no PRODIST), onde as concessionárias que apresentaram os piores desempenhos pagariam uma multa média maior por usuário. A segunda proposta descreve uma metodologia de tarifas diferenciadas por descontos (TARDIF). Nessa metodologia os DIC dos usuários de um mesmo nível de tensão foram classificados em 5 intervalos múltiplos de sua média coletiva (DEC). Os últimos 3 intervalos de classificação correspondem aos usuários que tiveram a pior qualidade do serviço no ano. Para esses usuários foram definidos descontos tarifários que compensariam os prejuízos no seguinte ano. Nos resultados obtidos, as multas médias dos usuários ressarcidos conservam a relação com a média de atendimento e com a dispersão dos dados, sendo o último o critério mais dominante. / This work presents a review of the methodology used in PRODIST 2010, and alternative proposals for setting targets and rates depending on quality of service (QoS). All analysis are supported in statistical interruption data studies of 6 electricity distribution companies (EDC) between 2007 and 2008 with different characteristics of DEC, FEC, number of users and sets. The first proposal called Single Rate - Single Goal (TAMU in Portuguese) proposes the same goal of QoS to all same voltage level users. This proposal sets as a general criterion that 10% of users with worst voltage level attendance must be compensated for getting poor QoS. In order to achieve this goal, the top voltage levels of each company were determined from its cumulative frequency histograms of the user individual indicators value. This procedure guarantees the same percentage of users compensated in all EDC voltage levels. The results obtained by calculating the average penalty per user refunded maintain a fairly consistent with deterioration of collective indicators values (this does not happen in PRODIST 2010), where EDC with worst performances will pay a higher average penalty per user. The second proposal describes a different discount rate methodology (TARDIF in Portuguese). In this methodology, the DIC of users with same voltage level were classified into five intervals of its collective average (DEC). The last three classification intervals correspond to users who have had the worst QoS in the year. For these users were defined discount rates that would compensate the losses next year. In the obtained results, the average penalties of refunded users maintain the relationship between the average attendance and the data scattering, being the last one the most dominant criterion.
42

Propostas de procedimentos para o estabelecimento de metas de qualidade do serviço de distribuição de energia elétrica. / Proposals of procedures for setting targets for power distribution service quality.

Jenny Paola González Pérez 06 March 2012 (has links)
Este trabalho apresenta uma análise crítica da metodologia usada no PRODIST 2010, e propostas alternativas para a fixação de metas e tarifas em função da qualidade do serviço. Todas as análises se sustentam em estudos estatísticos dos dados de interrupções nos anos 2007 e 2008 de 6 empresas distribuidoras de energia com diferentes características de DEC, FEC, número de usuários e número de conjuntos. A primeira proposta chamada de Tarifa Única Meta Única (TAMU) propõe a mesma meta de qualidade do serviço para todos os usuários de um mesmo nível de tensão. Na proposta se fixou como critério geral que 10% dos usuários pior atendidos de um nível de tensão devem ser ressarcidos por má qualidade do serviço. Para alcançar esse objetivo as metas dos níveis de tensão de cada empresa foram fixadas a partir dos seus histogramas de frequência acumulada dos indicadores individuais dos usuários. Esse procedimento garante que a percentagem de usuários ressarcidos seja igual em todos os níveis de tensão das empresas. Os resultados obtidos no cálculo da multa média por usuário ressarcido conservam uma coerência justa com a piora dos indicadores coletivos (isto não acontece no PRODIST), onde as concessionárias que apresentaram os piores desempenhos pagariam uma multa média maior por usuário. A segunda proposta descreve uma metodologia de tarifas diferenciadas por descontos (TARDIF). Nessa metodologia os DIC dos usuários de um mesmo nível de tensão foram classificados em 5 intervalos múltiplos de sua média coletiva (DEC). Os últimos 3 intervalos de classificação correspondem aos usuários que tiveram a pior qualidade do serviço no ano. Para esses usuários foram definidos descontos tarifários que compensariam os prejuízos no seguinte ano. Nos resultados obtidos, as multas médias dos usuários ressarcidos conservam a relação com a média de atendimento e com a dispersão dos dados, sendo o último o critério mais dominante. / This work presents a review of the methodology used in PRODIST 2010, and alternative proposals for setting targets and rates depending on quality of service (QoS). All analysis are supported in statistical interruption data studies of 6 electricity distribution companies (EDC) between 2007 and 2008 with different characteristics of DEC, FEC, number of users and sets. The first proposal called Single Rate - Single Goal (TAMU in Portuguese) proposes the same goal of QoS to all same voltage level users. This proposal sets as a general criterion that 10% of users with worst voltage level attendance must be compensated for getting poor QoS. In order to achieve this goal, the top voltage levels of each company were determined from its cumulative frequency histograms of the user individual indicators value. This procedure guarantees the same percentage of users compensated in all EDC voltage levels. The results obtained by calculating the average penalty per user refunded maintain a fairly consistent with deterioration of collective indicators values (this does not happen in PRODIST 2010), where EDC with worst performances will pay a higher average penalty per user. The second proposal describes a different discount rate methodology (TARDIF in Portuguese). In this methodology, the DIC of users with same voltage level were classified into five intervals of its collective average (DEC). The last three classification intervals correspond to users who have had the worst QoS in the year. For these users were defined discount rates that would compensate the losses next year. In the obtained results, the average penalties of refunded users maintain the relationship between the average attendance and the data scattering, being the last one the most dominant criterion.
43

DEC Recommended Practice Can Make a Difference in the Outcomes for Young Children with Disabilities Who Have Experienced Abuse and Their Families

Trivette, Carol M., Corr, Catherine 11 May 2016 (has links)
Children who are abused are at a higher risk for developing a disability, and, conversely, children with a disability are at a higher risk of being abused and neglected. I know that you don’t want to hear any more, but you need to, because you can help. This presentation will use a case study approach to focus on the actions of professionals who were trying to do the very best for a young child who became disabled as a result of abuse. Though the outcome met all of the specific requirements of child welfare and early intervention programs, clearly the outcome was not the best for this child and family. In this session using the new DEC Recommended Practices, participants will develop a picture of how the DEC RP might have been used and how the result would have been very different.
44

西南聯大的研究 / SouthWest Associated University,1937-1946:A Study of Wartime China's Higher Learning Institute.

楊正凱, Yang,Cheng Kai Unknown Date (has links)
國立西南聯合大學(以下簡稱聯大),是抗日戰爭的產物,由北大、清華 、南開三所平津著名大學組成。鹿橋(吳訥蓀, 聯大三十二年外文系畢 業生)的《未央歌》,就是以描述聯大而膾炙人口。但是, 小說與史實 總有差別,而台灣與大陸對聯大的專門研究迄未出現, 故本論文嘗試以 教育部檔案、國史館檔案、教育部出版品、回憶錄、雜文、訪問記錄、 戰時報刊及有關大學理念的學術文獻,依史學方法,研究聯大史實。研究 結果的重點是:一、抗戰初起,教育部有「平時教育」政策,使聯大得以 成立與維持。二、為適應戰時環境,使學校有效運作,發展出「聯大模式 」, 經由三校教授意見整合與權力分配,教授會、各項委員會、 系主任 成為聯大運作的重心,教授是學校主體,教學與行政工作,多由教授主導 。 雖然有不合法規之處,但聯大教授認為合理。三、教育部想收攏權力 ,引起一些聯大教授抗爭。在調整學校行政組織、黨團進入校園等方面, 聯大與教育部的衝突最明顯。 由於經費權柄在教育部,聯大必須接受部 定行政組織、新定課程表、 師資審核和國民黨、青年團進入校園。四、 國民政府擴張大學教育,培育青年,保留社會菁英,用心良苦。 但未能 有足夠的財力支持,使師生飽受通貨膨脹之苦,陷於飢餓邊緣, 身心受 創。不但教育品質無法維持,也使部分師生有怨尤政府之情。五、教育部 的平時教育,並未貫徹實行,側重擴張實用科系, 使聯大工學院、經濟 系學生偏多,各院學生公費待遇也不公平。六、抗戰勝利後的學潮,始於 聯大。中共在學生社團間的勢力, 在學潮中發揮極大作用。由於政府鎮 壓、昆明政局詭異、 中共充分宣傳利用等因素,學潮後的聯大,已非良 好的學習場所。七、從逃難南下,到三校復員止,聯大並非善始善終, 而是從抗戰初的團結,走向離心離德。於重重問題中,聯大解散,留下不 少遺憾。 學潮與校園情況,其實也反映了國共勢力的消長。八、總結而 論,聯大前期、中期,能在艱苦環境中調整適應, 應對教育部、雲南當 局,營造合理、有利的生存情境,教學和研究均有成績, 是難能可貴的 。聯大後期,由於學潮、局勢不安等因素, 「聯大模式」教授主導校政 的權力結構,遭受考驗,教授會分裂,學校草草結束。
45

A masterpiece of diplomacy: Anglo-American negotiations at Ghent, (August-December, 1814)

Wood, James Cleveland, 1941- January 1966 (has links)
No description available.
46

Uma implementação do método do Gradiente Projetado na solução do problema não-linear de controle do conversor catalítico

Carvalho, Joao Batista da Paz January 1996 (has links)
O presente trabalho trata da formulação, algoritmização e implementação numérica de um problema não-linear de controle de fronteira livre sujeito a restrições também não lineares definido em [Fri 94] e relativo ao modelo de funcionamento de um conversor catalítico monolítico cerâmico. São apresentados resultados de algumas simulações numéricas, usando um programa em FORTRAN77, no ambiente de estações de trabalho SUN e DEC alfa 3000.
47

Uma implementação do método do Gradiente Projetado na solução do problema não-linear de controle do conversor catalítico

Carvalho, Joao Batista da Paz January 1996 (has links)
O presente trabalho trata da formulação, algoritmização e implementação numérica de um problema não-linear de controle de fronteira livre sujeito a restrições também não lineares definido em [Fri 94] e relativo ao modelo de funcionamento de um conversor catalítico monolítico cerâmico. São apresentados resultados de algumas simulações numéricas, usando um programa em FORTRAN77, no ambiente de estações de trabalho SUN e DEC alfa 3000.
48

Uma implementação do método do Gradiente Projetado na solução do problema não-linear de controle do conversor catalítico

Carvalho, Joao Batista da Paz January 1996 (has links)
O presente trabalho trata da formulação, algoritmização e implementação numérica de um problema não-linear de controle de fronteira livre sujeito a restrições também não lineares definido em [Fri 94] e relativo ao modelo de funcionamento de um conversor catalítico monolítico cerâmico. São apresentados resultados de algumas simulações numéricas, usando um programa em FORTRAN77, no ambiente de estações de trabalho SUN e DEC alfa 3000.
49

An examination of the influence of selected works of Franz Schmidt on the Concerto for Trumpet and Orchestra and the Sonata for Trumpet and Piano by Karl Pilss.

Wacker, John Mainard 08 1900 (has links)
The Concerto for Trumpet and Orchestra and the Sonata for Trumpet and Piano by Karl Pilss were written in 1934 and 1935, respectively. They are examples for solo trumpet of the late German Romantic style of melody, harmony, form and structure. Musicians and audience often overlook composer Karl Pilss outside his native Vienna. His ties to the Trompeterchor der Stadt Wien and the National Socialist Party during the years preceding the Second World War have limited widespread acceptance of this composer. Pilss' output includes concertos for trumpet, horn, bass trombone, and piano, sonatas for trumpet, violin, and oboe, wind quintets and octets, piano pieces, choral works, and numerous large and small brass works. Pilss' teacher Franz Schmidt is more widely known. His four symphonies provide examples of post-Romanticism at the beginning of the twentieth century. His characteristic use of melody, harmony, form and structure is in the mold of Richard Strauss. Schmidt did not write any works for solo trumpet. However, his Symphony No. 4 begins and ends with extended passages for solo trumpet. Pilss inherited and adopted many of Schmidt's melodic, harmonic and formal traits. These can be clearly heard in his Concerto for Trumpet and Orchestra and the Sonata for Trumpet and Piano. This work discusses in detail the musical and compositional connection between Karl Pilss and his teacher, Franz Schmidt. Musical elements of melody, harmony, form and structure are used to illustrate the close connection between pupil and mentor. The use of the characteristic "Schmidt chord" in Pilss' works cements the link between the two composers. The Concerto for Trumpet and Orchestra and the Sonata for Trumpet and Piano deserve wider acceptance on the basis of their musical merit and as unique examples of the late German Romantic style for solo trumpet.
50

Fosforåtervinning ur förbränningsaska från rötslam och rötrest / Phosphorus recycling from digested sewage sludge ash and digestate ash from municipal food waste

Jonsson, Martin January 2015 (has links)
Fosfor är ett ändligt näringsämne som på senare tid uppmärksammats i samband med övergödning och bristen som råvara. Näringsämnet är livsviktigt för likväl människor som djur och växter och de brytbara fosforreserverna börjar ta slut. Det gäller att i framtiden applicera hållbara fosforåtervinningsmetoder för att ta tillvara på mängden fosfor som finns i omlopp. Avloppsslam är ett avfall som växer till storleken och med befolkningsmängden. Rötat avloppsslam tillsammans med andra avfall i form av rötrester innehåller nyttiga näringsämnen så som fosfor, kväve och kalium men också onyttiga spårämnen, patogena ämnen, organiska rester och tungmetaller. Rötslam innehåller även läkemedelsrester och mikroplaster. I dagens läge är det tillåtet att sprida rötslam och rötrest på åkermark för att återföra fosfor tillsammans med andra näringsämnen till jordbruket. Kommande regelverk innebär skärpta lagkrav på rötslammet som måste genomgå någon form av förbehandling innan innehållet får användas som en resurs. Ett alternativ är att vidta strängare krav på hygienisering utav slammet. Det kan ske med pastörisering, termofil rötning eller annan behandling vid högre temperaturer. Ett annat, mer lovande alternativ är förbränning av rötslam och rötrest. Vid förbränning destrueras en stor mängd av oönskade ämnen så som läkemedelsrester, patogena ämnen och kvarblivet organiskt material. Beroende på i vilken panntyp förbränning sker, CFB-, BFB-panna eller rosterpanna kvarblir en askfraktion som botten- och flygaska. I askfraktionerna finns fosfor och till stora delar tungmetaller kvar. Fosforn är relativt inert vid temperaturförändringarna medan lättflyktiga tungmetaller evaporerar och ansamlas till störst del i flygaskan. Rapporten utvärderar ett antal olika fosforåtervinningsmetoder som kan indelas i två huvudkategorier, termo- och våtkemiska återvinningsmetoder. Syftet är att beskriva de olika metoder samt uppskatta dess kostnader, kommersiell mognad samt ange för- respektive nackdelar för metoderna ur ett hållbart perspektiv. Till de termokemiska metoderna tillhör termisk behandling av avloppsslam i en BFB-panna och ASH DEC-processen. Den förra är under utveckling och befinner sig på labb/bänk-skala. Den termokemiska behandlingsmetoden i BFB-panna är en dekontamineringsprocess där askan kan spridas direkt på åkermark då fosforn befinner sig i form av växttillgängligt whitlockit i bottenaskan. Systemet beräknas ha en investeringskostnad på 72 Mkr, med en pay-back tid på 4,4 år och kapacitet på minst 1000 ton aska/år. ASH DEC-processen är också en termokemisk dekontamineringsprocess där produkten utvinns i form av natriumkalciumfosfater. Metoden uppskattas ha en investeringskostnad på 140-170 Mkr, återbetalningstid på ca 4 år för en kapacitet på ca 30 000 ton aska/år. I investeringskostnaden ingår en roterugn Processen är kommersiell och anläggningar finns i Tyskland och Österrike. De våtkemiska fosforåtervinningsmetoderna innefattar CleanMAP-technology, PASH-Processen, SEPHOS-processen, SESAL-phos processen och BioCon-Processen. Gemensamt för dessa processer är att olika laknings- och upplösningstekniker används samt att ett processvatten bildas och måste genomgå vattenrening. CleanMAP-technology är en lovande våtkemisk process under utveckling. Pågående förprojektering ska innefatta en anläggning med kapacitet upp till 30 000 ton aska/år, vilket motsvarar ett omhändertagande på ca 30 % av Sveriges idag producerade avloppsslam. CleanMAP ger en klassificerad produkt i form av 100 % rent ammoniumfosfat som kan användas direkt som gödningsmedel och är vattenlösligt. Processen anses enligt EasyMining Sweden AB vara energieffektiv med låga driftkostnader, god tungmetall reduktion och enkel att implementera i enbefintlig anläggning. Tekniken är under utveckling och eftersom ingen anläggning byggts finns inga investerings- eller driftskostnader publicerade. PASH-processen är en lakningsmetod som bildar kalciumfosfat som slutgiltig produkt. Processen ger en reduktion av tungmetaller och andra metaller, specifikt aluminium. Processen är därför lämplig att använda på avloppsslam där reningsverk använt aluminium som fällningskemikalie. PASH-processen beräknas ha en investeringskostnad på ca 46 Mkr, driftkostnad på 37 Mkr vid en kapacitet på 30 000 ton aska/år och en fosforåtervinning på ca 1 700 ton/år. SEPHOS-processen använder syra och bas för upplösnings av aska. Fosfor återvinns som aluminiumfosfat som sedan genomgår ett mer avancerat steg (Advanced SEPHOS-process), i syfte att slutligen erhålla kalciumfosfater som är mer växttillgängligt då aluminium kan orsaka skada på växternas rötter.SEPHOS-processen är under utveckling och det finns inga investerings- eller driftkostnader att tillgå. SESAL-Phos processen är en flerstegsprocess med upplösning av aska med syra och bas för att bilda växttillgängligt kalciumfosfat som produkt. Processen är under utveckling och information om investerings- och driftkostnader finns inte att tillgå. BioCon-Processen är baserad på en jonbytesteknik för att separera oönskade metaller och oorganiska element för att erhålla fosforsyra. Processen är omfattande och kräver en mängd olika tillsatskemikalier. Processen används i Danmark vid en förbränningsanläggning och implementerades i Sverige under tidigt 2000-tal men anläggningen har lagts ned vid på grund av driftproblem. De metoderna som är mest lovande för Fortum Värme att vidare granska, sett till de för och nackdelar som erhållits, är CleanMAP-technology, ASH DEC-processen och termisk behandling i BFB-panna. CleanMAP-teknologin innefattar driftkostnader i form av hög kemikalieförbrukning, och kräver mindre anläggningsyta än ASH DEC-processen. ASH DEC-processen är kommersialiserad i Tyskland och Österrike och har drifterfarenhet av anläggningen, vilket är en god anledning till implementering i Sverige. Termisk behandling i BFB-panna har potential att fungera både praktiskt och ekonomiskt. Trots att denna process är långt ifrån kommersiell, kan den i framtiden vara en god kandidat att implementera för fosforåtervinning. Kvaliteten på erhållet rötslam och rötrest bör ha en låg ask- och fukthalt vilket ger en bättre förbränning. Biobränsle har en låg askhalt men hög fukthalt. Samförbränning av rötslam och rötrest tillsammans med biobränsle är att föredra rent ekonomiskt eftersom investering i en mono-förbränningsanläggning enbart för slam kan undvikas. En nackdel är dock att koncentrationen av fosfor i askan blir lägre och kostnaden för fosforåtervinning ökar. Fukthalten på biobränslet bör vara så lågt som möjligt, dels för att uppnå en tillräcklig koncentration av fosfor, dels för att erhålla ett rimligt värmevärde på bränsleblandningen vid förbränning. Huruvida förbränning av rötslam eller strängare krav på hygienisering av avloppsslam är ett tillvägagångssätt för behandling är i dagens läge en pågående diskussion. I ett initialt skede är ett alternativ att förbränna mindre mängder av rötslammet i de fall tungmetallhalterna, särskilt kadmium, är för höga för att spridas på åkermark. Ur ett hållbart perspektiv är det lämpligt att se förbränning och efterföljande fosforutvinning ur aska som ett gott alternativ till behandling av ett, till mängden, växande avfall. Både den sociala- ochmiljömässiga aspekten behandlas då avfallsvolymer reduceras, läkemedelsrester, smittoämnen och andra patogena ämnen destrueras samtidigt som tungmetaller reduceras och fosfor återvinns. Ur ett ekonomiskt perspektiv är kostnaderna för att återvinna fosfor i dagsläget för höga i jämförelse med vad det kostar att bryta råfosfater. Det kostar ca 28-38kr/kg för framtagning av återvunnen fosfor, beroende på vilken metod som används. Försäljningspriset för fosfor är ca 3 kr/kg. Tillsvidare gäller det att utveckla och effektivisera fosforåtervinningsmetoderna så att driftproblem kan minimeras samt investerings- och driftkostnader kan reduceras vilket medför större attraktion för företag att investera i återvinningsmetoderna. / Phosphorus is an endless nutrient that lately has been drawing much attention in correlation to over-fertilization and as a scarce commodity. Phosphorus is essential to all life, humans, animals and plants and the workable phosphorus back-ups seems to be running out. It is therefore important in the future to apply sustainable phosphorus recovery methods to take care of the circulation of phosphorus in today’s society. Sewage sludge is a waste that grows with the increase of population. Digested sewage sludge among other wastes such as digested municipal food waste contain beneficial nutrients such as phosphorus, nitrogen and potassium but also unhealthy trace elements, pathogenies, heavy metals and unwanted organic material. Sewage sludge also contain drug residues and micro plastic fibers. As of today it is allowed to spread sewage sludge and digested municipal food waste on farm land to return phosphorus together with other nutrients. Future set of regulations will probably be subtilized which will influence the usage of sewage sludge spreading on farm land. The sewage sludge will most likely have to go through some kind of pretreatment before being used as a resource. An alternative is to institute harder demands on hygenization which can be performed by pasteurization, thermophilic digestion or other treatments involving an increase in temperature to get rid of harmful substances. Another alternative that seems more promising is combustion of sewage sludge and digested municipal food waste, which will destroy unwanted substances such as drug residues, pathogenies, and left-over organic material. Depending in which type of pan the combustion will take place, CFB- (Circulated fluidized bed), BFB- (Bubbling fluidized bed) or grate boiler it will leave different amount of bottom ash and fly ash. Phosphorus and larger amount of heavy metals will be concentrated in the ash. Phosphorus is inert to the temperature changes and finds itself contained in the bottom ash, meanwhile heavy metals evaporate and stack up in the fly ash. This report evaluate different kinds of phosphorus recovering methods that can be divided in to main categories, thermo chemical and wet chemical recovery methods. The main purpose is to describe the methods, estimate its cost, find out if the method is ready for commercial use and specify the advantages and disadvantages. Thermo chemical treatment of sewage sludge ash in a BFB and the ASH DEC-process is two thermo chemical treatment methods this report brings up. The first mentioned is under development and its main purpose is to decontaminate the ash and use phosphorus rich whitlockite ash as a fertilizer. The system has an evaluated investment cost of 72 MSEK, with a pay-back time of 4,4 years and a capacity of at least 1000 ton ash/year. The ASH DEC-process is also a decontaminating process where the product is reclaimed as sodium calcium phosphates. The method estimated investment cost is around 140-170 MSEK with a pay-back time of 4 years and a capacity of 30 000 ton ash/year. The ASH DEC-process is currently in use in Germany and Austria. Among the wet chemical phosphorus recovery methods presented in this report is, CleanMAP-technology, PASH-Process, SEPHOS-Process, SESAL-Phos process and the BioCon-process. In common for these process is the different leaching and dissolution techniques and the origin of a process water that has to be cleaned before released. CleanMAP-Technology from EasyMining Sweden AB is much promising currently under development. The layout design will encapsulate a capacity of 30 000 ton ash/year, which correspond to the apprehending of nearly 30 % of the produced sewage sludge in Sweden today. CleanMAP-technology gives a water soluble product, ammonium phosphate, with nearly 100 % purity and can be used directly on farm lands. The process is energyefficient with low operating costs and a propitious heavy metal reduction. The technique is under development with no demonstration and no public data of investment costs or operating costs available. The PASH-process is an acid leaching method and form calcium phosphate as final product. The process gives a reduction of heavy metals and other metals, aluminum in specific. The process is therefore most appropriate to use on sewage sludge from water treatment plants that uses aluminum as a precipitate chemical. The investment cost is estimated to around 46 MSEK with an operating cost of 37 MSEK and a capacity of 30 000 ton ash/year and a phosphorus recovery of 1 700 ton/year. The SEPHOS-process uses acid and base for the dissolution of ash. Phosphorus is recovered as aluminum phosphate that ultimately is passed through a more advanced step called “advanced SEHPOS-process” in purpose to obtain calcium phosphates which are more suitable for plants because aluminum can cause damaged to the roots. The SEPHOS-process is currently under development and there are no public released data on investment costs or operating costs. The SESAL-Phos process is a multi-stage process with dissolution of ash with acid and base to obtain calcium phosphate as final product. The process is currently under development. The BioCon-process is based on ion exchange technology to be able to separate unwanted metals and inorganic elements. The obtain product is mainly phosphorus acid. The process is comprised and has a large variety of chemical demand. The process is used in Denmark and was implemented in Sweden in early 21th century but had to close down due to operating problems. Phosphorus recovery methods that seems most promising for Fortum Värme, accordingly to the advantages and disadvantages is CleanMAP-technology, ASH DEC-process and in the future thermo chemical treatment of sewage sludge ash in a BFB-boiler. CleanMAP-technology can implicate high operating costs due to the addition of chemicals, but they will be part of the products and the facility will be smaller than the ASH DEC-process. The ASH DEC-process is a commercial process in use in both Germany and Austria and has knowledge of operating which will be one of the reasons to consider implementation in Sweden. Thermo chemical treatment in a BFB-boiler has potential both practical and economical to be considered for implementation in the future even though it’s far from a commercial use. The quality of digested sewage sludge and digested municipal food waste should have a low ash- and moisture content. Bio fuel contain low ash content but high moisture content. Co-combustion of digested sewage sludge and municipal food waste along with bio fuel is to prefer in an economically point of view because no further investment in a mono-combustion plant is needed for the sludge only. One disadvantage is that the concentration of phosphorus in the ash will be lower and the cost of phosphorus recovery will increase. An appropriate moisture content of the bio fuel should be as low as possible to obtain higher phosphorus concentration in the ash and to get a tolerable heat value in the fuel mix during combustion. Whether combustion of digested sewage or more severe demands on hygenization of sewage sludge is the wanted procedure for treatment is today an ongoing discussion. Initially, one alternative is toburn small amounts of digested sewage sludge in those cases heavy metal content is too high to be spread on farm lands, especially cadmium. In a sustainable perspective it would be appropriate to see combustion followed by phosphorus recovery methods from ash as a good option of treatment. Both the social- and environmental aspect is attended when the volume of waste is decreased, drug residues destroyed, infectious agents and other pathogenic substances destroyed meanwhile heavy metals is concentrated and gathered for safe depositing. In an economical point of view it is confirmed that the costs to recover phosphorus is today too high in comparison to workable resources. Today the cost of recovered phosphorus is around 28-38 SEK/kg, depending on which method used and the selling price is around 3 SEK/kg, which makes it non profitable. For the time being the phosphorus recovery methods need further attention to be able to develop and expand upon. The need is also to make them more effective and to learn how to encounter operating failures and minimize the investment- and operating costs. If so, the recovery methods will bring more attention to companies and make them more interested in investment.

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