Chile and Santiago are struggling with heavy environmental problems as a consequence of urbanisation and industrialisation. In the Santiago region the air is seriously contaminated and most of the rivers are classified as heavily polluted. The aim of this thesis is to survey the industrial fluid waste situation in the Santiago region and to make suggestions on technological improvements or process changes. The purpose is also to study five different enterprises more closely and to give more detailed suggestions for improvement. Another purpose is to summarize relevant Chilean legislation. Information, provided by the supervisory authority, about the release of industrial wastewater to rivers has been analysed. Deep interviews have been made with authorities and consultants. Five enterprises have been visited; a brewery, a dairy, a bakery, a producer of cooked meat and a surface treatment industry. The present treatment of the wastewater was studied at the plants and the information was completed with a questionnaire to the responsible at each company. The contamination load released to the Chilean rivers is heavy. The rivers in southern Chile receive the biggest loads of BOD and SS and the rivers in central Chile were the most exposed to discharges of the metals Cr, Cu, Zn and CN as well as phenols. The industrial discharge into the rivers of Santiago RM and Region VII is also to a large extent characterized by high concentrations of BOD and SS. Large releases of oils and greases, nitrogen and phosphorus are also fairly common, as are too high or too low pH levels. The food industry is the most contaminating sector, but also tanneries have great problems with effluents exceeding limits. All five companies visited share the need to take measures towards more water saving technologies. The brewery, the producer of cooked meat and the surface treatment company also need end-of-pipe-treatment of their wastewater. In many cases, the recommended and most economic alternative is to separate the flows with the highest concentration of polluting substances for internal treatment, while releasing the rest of the wastewater to the outside sewage system. The costs of the suggested changes must be balanced against the present costs for treatment of wastewater and remaining solid waste as well as the costs for alternative treatments. The economic incentives for Chilean companies to invest in wastewater treatment plants or to optimize the processes until today have been few. Cost reductions may be achieved by savings in water consumption and reuse of raw material. Another motive could be to keep “one step ahead” if the discharge limits in the future are tightened up leading to rising costs. / Chile och Santiago brottas med omfattande miljöproblem till följd av urbanisering och industrialisering. I santiagoregionen är luftföroreningarna svåra och de flesta floderna klassas som gravt förorenade av CONAMA, det chilenska naturvårdsverket. Syftet med examensarbetet är att kartlägga situationen i santiagoregionen med avseende på industriell avloppsrening samt att ge förslag på förbättring av teknik eller förändring av processer. Dessutom är syftet att studera fem industrier närmare och att ge mer detaljerade förslag på åtgärder. Syftet är också att ge rekommendationer för fortsatt utveckling av relevant chilensk lagstiftning. Uppgifter från tillsynsmyndigheten för utsläpp till ytvattendrag har studerats och djupintervjuer har gjorts med myndigheter och konsulter. Fem olika industrier besöktes; ett bryggeri, ett mejeri, ett bageri, ett charkuteri samt en ytbehandlingsindustri. Nuvarande hantering av processvattnet studerades på plats och med hjälp av ett frågeformulär kompletterades uppgifterna av ansvariga på företagen. Föroreningsbelastningen på Chiles floder är stor. Floderna i södra delen av landet tar emot störst mängder organiskt material och suspenderat material medan centrala Chiles floder är värst drabbade av utsläpp av metallerna Cr, Cu, Zn och CN samt utsläpp av fenoler. Utsläppen från industrin till floderna i Region Metropolitana och Region VII kännetecknas också i stor utsträckning av höga halter BOD och suspenderat material. Relativt vanligt är också stora utsläpp av oljor och fetter, kväve, fosfor samt för höga eller låga för pH-värden. Det är främst flera olika typer av livsmedelsindustri, som har de största utsläppen till floderna, men även garverierna har stora problem med överskridande av gränsvärden. Gemensamt för de fem besökta företagen är att vattenbesparande åtgärder bör vidtas för att minska volymen avloppsvatten som går till extern eller intern behandling. Bryggeriet, charkuterifabriken och ytbehandlaren behöver även end-of-pipe-rening. Det kan ofta vara lämpligt och mer ekonomiskt att avskilja de flöden som har högst halt av föroreningar till den interna reningsanläggningen. Resten av avloppet kan i vissa fall släppas ut på avloppsnätet. Kostnader för föreslagna åtgärder måste vägas mot aktuella kostnader för behandling av avlopp och restprodukter, samt kostnader för alternativa behandlingar. Incitamenten, bl a de ekonomiska, för chilenska företag att skaffa eget reningsverk eller att resurseffektivisera produktionen har hittills varit små. Kostnadsminskningar kan uppnås genom sänkt vattenförbrukning samt återanvändning av råmaterial. Ytterligare en drivkraft kan vara att ”ligga steget före” om utsläppskraven i framtiden skärps och kostnaderna därmed ökar.

Bioenergi är en stor industri i Sverige och står för en betydande del av energiomsättningen. Bioenergi i form av flis förvaras runt om i landet på hög i väntan på förbränning. Då högarna läggs upp startar olika processer som värmer upp stacken, ofta till temperaturer på 50°C under det första dygnet. En vanlig ansats i litteraturen är att denna temperaturstegring beror på aerob nedbrytning. Arbetet ämnar undersöka om denna uppvärmning endast beror av mikrobiella aktiviteter. Hypotesen prövas genom kalorimetriska mätningar av effekt från prover av flis och simulering av första dygnets temperaturutveckling i ett program som programmeras under arbetes gång. I modellen så betraktas för enkelhets skulle flisstacken som en avlång figur med rektangulärt tvärsnitt. Figuren delas sedan in i lämpligt stora beräkningsceller. Problemet löses genom att iterativt räkna fram ett strömningsfält. Strömningsfältet och effekterna som räknas ut hålls sedan konstanta under ett tidssteg, 5-15min. Den magasinerade värmeenergin används sedan för att räkna fram en ny temperatur som så ger ett nytt strömningsfält och nya effekter. I modellen användes enbart explicita metoder eftersom de är snabbare och mycket enklare att programmera. Ett flertal experiment i kalorimeter genomfördes med olika prover av flis och torv. Prover med barkflis gav högst utslag. Den högsta effekten som uppmättes var 2,16W/kg TS. Då effekter av denna storleksordning användes som inre effektgenerering i programmet gav detta inte en temperatur ökning motsvarande sådana som uppmätts i verkligheten. Detta tyder på att mer än aerob nedbrytning krävs för att ge en temperatur på över 50°C. / Bioenergy is a major industry in Sweden and accounts for a significant part of the energy production. Bioenergy in the form of wood chips is stored in piles across the country awaiting combustion. When the piles are acumulated, various processes that heat the stack begin, often to temperatures of 50 °C during the first day. A common approach in the literature is that this temperature rise is due to the aerobic decomposition. This paper will investigate whether the microbial activity is the fundamental cause for warming. The hypothesis is tested by calorimetric measurements of power from the samples of wood chips and simulation of the first day's temperature development in a programme that was desinated. For simplicity the model considers an oblong wood chip pile with rectangular cross-section. The pile is then subdivided into appropriately sized calculation cells. The problem is solved by calculating a flow field iteratively. The flow field and the effects that are calculated is then static during one time step for approximately 5-15 minutes. The produced heat energy is then used to calculate a new temperature, which renders a new flow field and new powers. The model uses only explicit methods because they are faster and much easier to programme. Several calorimetric experiments were carried out with various samples of wood chips and peat. Samples of bark chips achieved the highest result. The highest power measured was 2.16 W / kg DM. When the effects of this magnitude were used as internal power source in the programme the temperature did not increase corresponding to those measured in reality. This suggests that more than aerobic decomposition is needed to reach a temperature above 50°C.

Small-scale anaerobic digesters, known as biogas plants, were applied as an optimal livestock waste treatment as well as biogas supply for cooking and lighting demand for small-scale farmers in Vietnam. Although the biogas technology was introduced for nearly 30 years, the number of the constructed biogas plants is still limited. The current development of biogas plants is far below the real demand on livestock waste treatment that has increased significantly. This paper gives a comprehensive overview on the biogas plant development in Vietnam and attempts to address the challenges and discuss appropriate solutions for the further biogas development. / Mô hình lên men yếm khí quy mô nhỏ (được biết với tên hầm ủ khí sinh học) đã được ứng dụng hiệu quả trong xử lý chất thải chăn nuôi cũng như cung cấp nguồn nhiên liệu phục vụ nhu cầu nấu ăn và thắp sáng cho các hộ chăn nuôi nhỏ ở Việt Nam. Mặc dù đã hiện diện gần 30 năm, nhưng số lượng hầm ủ khí sinh học vẫn còn hạn chế. Sự gia tăng số lượng hầm ủ khí sinh học chưa theo kịp với nhu cầu về xử lý chất thải chăn nuôi đang ngày càng gia tăng. Bài báo trình bày các chặng đường phát triển của hầm ủ khí sinh học tại Việt Nam, ghi nhận các thách thức trong việc nhân rộng hầm ủ khí sinh học trong thực tế và thảo luận một số giải pháp để phát triển công nghệ khí sinh học.

Today, numerous studies indicate the presence of synthetic organics such as nonylphenol (NP) compounds in wastewater. NP compounds are a group of chemicals including nonylphenol, nonylphenol polyethoxylates (NPnEO) and nonylphenoxy polyethoxy acetic acids (NPnEC). Since NP compounds have significant industrial, commercial and domestic use, they enter environmental systems and reach human beings from various pathways. Their presence is of concern because they are toxic, carcinogenic and endocrine disrupting due to their ability to mimic oestrogen hormone. The information available on the degradation of NPnEOs, is such that degradation starts with the reduction of ethylene oxide units, resulting in the formation of nonylphenol, nonylphenol mono- or diethoxylate (NP1EO and NP2EO) and nonylphenoxy acetic acid (NP1EC). Although their fate during wastewater treatment was investigated in the past, not many research investigating their fate in sludge treatment can be found. Therefore, the objective of this study is first to come up with reliable extraction and measurement methods for NP compounds and then to investigate the fate of NP2EO in aerobic digesters. After the development of techniques for the extraction and measurement of NP compounds, aerobic reactors spiked with NP2EO were operated. The samples were analyzed for solids content, COD, pH and NP compounds. The results showed that NP2EO degrades rapidly under aerobic conditions. As time proceeded, NP1EC formation was observed with the degradation of NP2EO, and NP1EC became the dominant specie. The solids concentration measurements showed that concentration of NP compounds did not affect the efficiency of aerobic digesters.

Contamination of groundwater supplies by gasoline and other petroleum-derived hydrocarbons released from underground or aboveground storage tanks is a serious and widespread environmental problem. Corrosion, ground movement, and poor sealing can cause leaks in tanks and associated piping. Petroleum hydrocarbons contain methyl tertiary-butyl ether (MTBE) (a fuel oxygenate), benzene, toluene, ethylbenzene, and xylene isomers (BTEX), the major components of gasoline, which are hazardous substances regulated by many nations. MTBE possesses all the characteristics of a persistent compound in the subsurface: high solubility, low volatility, low sediment sorption, and resistance to biodegradation. The objectives of this study were to (1) evaluate the biodegradibility of MTBE under aerobic conditions, and (2) assess the potential of using the aerobic bioremediation technique to clean up aquifers contaminated by MTBE. In this study, microcosms were constructed to determine the feasibility of biodegrading MTBE by intrinsic microbial consortia (aquifer sediments) under aerobic and aerobic cometabolic conditions. In the cometabolic microcosms, propane, ethanol, and BTEX were applied as the primary substracts to enhance the biodegradation of MTBE. The inocula used in this microcosm study were aquifer sediments collected from the contaminated-zones of a petroleum-hydrocarbon (including MTBE) contaminated site. Microcosms were constructed with nutrient medium (or site groundwater), sediments, and MTBE solution in 70-mL serum bottles sealed with Teflon-lined rubber septa. MTBE was analyzed using purge-and-trap instrument following gas chromatography (GC)/flame ionization detector (FID). Results show that the indigenous microorganisms were able to biodegrade MTBE under aerobic conditions using MTBE as the sole primary substrate. Microcosms with site groundwater as the medium solution show higher MTBE biodegradation rate. This indicates that site groundwater might contain some trace minerals or organics, which could enhance the MTBE biodegradation rate. Results show that the addition of BTEX would also enhance the MTBE removal. However, no significant MTBE biodegradation was observed in microcosms with propane and ethanol as the primary substrates. This reveals that the supplement of the second carbon source might inhibit the degradation of MTBE due to the preferential removal of some organics over MTBE. Results from the microcosm study suggest that aerobic biodegradation plays an important role on the MTBE removal. Intrinsic bioremediation is a feasible technology to remediate the studied MTBE-contaminated site.

Thesis (Ph.D.)--Ohio University, August, 2009. / Release of full electronic text on OhioLINK has been delayed until September 1, 2012. Includes bibliographical references (leaves 157-195)

Thesis (Ph.D.)--Ohio University, August, 2009. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until September 1, 2012. Includes bibliographical references (leaves 157-195)

Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 67-84).

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.