Prior to concerns of sustainability, almost all industrial engineering models tried to minimize cost or maximize profit. Sustainability awareness has recently forced the decision makers to also take into consideration such aspects as clean water use, or carbon dioxide emissions. In an effort to incorporate more aspects of sustainability in optimizing production efforts, we present a network model to handle trade-offs among dissimilar sustainability criteria. Since typically there are alternative choices for the various operations, the network allows parallel arcs between the same nodes. We also introduce the concept of generalized cost. Generalized cost is a vector quantity that includes not only a monetary measure, but also measures relevant to sustainability, such as carbon use or embodied energy. The approach leads to a multi-criteria decision making model, whose efficient frontier is obtained by the epsilon constraint method. Numerical work shows that the computational effort to obtain the efficient frontier is reasonable, allowing products of up to about a hundred activities to be solved with the current generation of personal computers.

Biosolids are valuable products which can be beneficially used in land application. However, the possibility of serious health effects on humans due to several pollutants in biosolids creates a big concern. To address this issue, risk-based methodologies are commonly used to evaluate health effects associated with the land application of biosolids. This study aims to investigate the health risks associated with ingestion of biosolids or soil mixed with biosolids by a child. This study is the first health risk assessment study in Turkey for land application of biosolids. Monthly sludge samples taken from Ankara Central Wastewater Treatment Plant (ACWWTP) in 2012 were analyzed for seven heavy metals (Cd, Cr, Cu, Hg, Ni, Pb, and Zn), and two organic contaminants (PCB and NPE) concentrations. To calculate health risks, methodologies developed by U.S. Environmental Protection Agency (U.S. EPA) and French National Institute for Industrial Environment and Risks (INERIS) were used. With both methods, cancer and non-cancer risks for the ingestion by a child pathway were determined and found to be below the acceptable cancer and non-cancer risk levels suggested by U.S. EPA and INERIS. Additionally, same health risk calculations were conducted for sludge and soil limit values provided in Turkish Regulation for the Use of Sewage Sludge in Agriculture (2010) to determine what the maximum health risk would be for the worst case scenario in Turkey. According to the results, even if the concentrations are at the maximum possible regulatory levels, the health risks are still low.

Landfilling is the most common method that is used in the final disposal of sludge all around the world as well as in Turkey. However increasing sludge quantities and limited landfilling areas make this method invalid. Use of sludge in agriculture presents a possible alternative for disposal. However, it also poses some risks to be evaluated. In this respect, it is important to identify heavy metal and pathogen content of sewage sludges because of their adverse health effects. This study aims to determine the heavy metal contents and pathogen levels of sludges from four different wastewater treatment plants of Turkey. The selection of plants was done according to the different treatment technologies applied to wastewater and sludge in those plants. Heavy metal analysis of sludges was conducted by using microwave assisted digestion procedure and pathogen levels were done by methods from Standard Methods (SM), ISO and USA EPA. After sampling and analysis, the results show that all the related metal concentrations are below the values that are set in the Soil Pollution Control Regulation of Turkey. However in sludges from Ankara and Kayseri wastewater treatment plants, Zinc and Nickel concentrations should be tracked carefully. The results related with pathogen levels in sludges show that dewatered sewage samples taken from Ankara, Kayseri and Kemer wastewater treatment plants do not meet neither Class A nor Class B fecal coliform limits set by USA EPA however lime stabilized dewatered sludge from izmir wastewater treatment plant meet the requirement. In addition, Salmonella levels in Kayseri dewatered sludges exceed the limit value.

The main objective of this study was to investigate two of the possible exploitation routes of anaerobic digestion (acid-phase and methane-phase) for the treatment of sugar-beet processing wastes, while producing valuable biobased products. For this purpose, four sets of laboratory experiments were carried out in a stepwise fashion: First, in the biochemical methane potential (BMP) assay (Set-up 1) wastewater and beet-pulp were efficiently digested (63.7&ndash / 87.3% COD removal and 69.6&ndash / 89.3% VS reduction) in batch anaerobic reactors. Secondly, wastewater and beet-pulp could simultaneously be converted to VFAs in acidogenic anaerobic reactors with considerable acidification degrees (43.8&ndash / 52.9%), optimizing the operational conditions (Set-up 2). Then, the produced VFAs were recovered by liquid-liquid extraction (Set-up 3), in which highest VFA recoveries (60.7&ndash / 97.6%) were observed at 20% trioctylphosphine oxide (TOPO) in kerosene with KD values ranging between 1.54 and 40.79 at pH 2.5. Finally, methane-phase anaerobic digestion was evaluated in two different reactor configurations, namely fed-batch continuously mixed reactor (FCMR) and anaerobic sequencing batch reactor (ASBR) (Set-up 4). Methane production yield of 255 &plusmn / 11 mL/g COD-added was increased to 337 &plusmn / 15 mL/g COD-added (32.2% increase in methane yield) when configuration was changed from FCMR to ASBR. In addition, tCOD removal was increased from 68.7 &plusmn / 2.2 to 79.7 &plusmn / 1.1%. Based on the result obtained in this study, it is postulated that, biorefining of sugar-beet processing wastes by anaerobic digestion can not only be a solution for environmental related problems, but also contribute to resource conservation and sustainable production via valuable bio-based product formation.

The objective of this study is to achieve vulnerability assessment of the groundwater by using DRASTIC Method which is developed by United States Environmental Protection Agency (USEPA). It is most commonly used overlay and index method all over the world. Evaluation of groundwater vulnerability would be performed by using computer programs which are based on Geographical Information System (GIS) in order to facilitate data management and spatial analysis. The term vulnerability, that is used in this study, could be defined as a degree of capacity of the geological settings which are above water table, cause as joining of contaminants to groundwater where imposed by environmental factors. All the groundwater has some degree of protection under natural condition. It is an important initial step to identify degree of vulnerability by an index which is provided by superimposition of the environmental and geological properties that are explained in DRASTIC Method. v At the end of the study by using a computer program together with DRASTIC Method a vulnerability map will be obtained. The vulnerability map is an informative tool from different aspects such as it is an initial step for taking an attention of risk of groundwater could be getting polluted in some areas. In addition, surface activities could be limited by focusing on groundwater protection strategies which are considering degree of vulnerability of areas that are delineated by DRASTIC vulnerability index. With the purpose of groundwater vulnerability assessment Kirikkale Plain is selected for a study area. Because of inappropriate management of the industrial and domestic wastes, lack of waste water treatment plants and uncontrolled agricultural activities cause this region proned to groundwater pollution. At the end of this study a groundwater vulnerability map of the Kirikkale Plain is obtained and attention is drawn to the places which are more vulnerable are pointed out.

Although there are some carbon capture and storage (CCS-CO2 sequestration) projects in all over the world, feasibility problems exist due to the high economical issues. The aim of this study is to evaluate the feasibility of a potential CCS project where the source of CO2 is Afsin Elbistan Thermal Power Plant. Selection of candidate sites in the vicinity of Diyarbakir, Batman and Adiyaman regions depends on sequestration criteria. According to sequestration criteria, CCS can be applied to &Ccedil / aylarbasi mature oil field, Midyat saline aquifer and Dodan CO2 gas field. Disposing of CO2 from the source of Afsin Elbistan Thermal Power Plant is analyzed by pipeline and tanker. CO2 capturing technologies are determined from published literature. CO2 transportation can be applied by pipeline or tanker. CO2 transportation cost by pipeline and tanker are compared. It has been calculated that, transportation by pipeline is more economical compared to tanker transportation. It is further found that the number of boosting pump stations, the length of the pipeline and CO2 mass flow rate are the issues that alter the economical aspect in the pipeline transportation. The transportation costs by tankers depend on fuel cost, distance, tanker storage capacity, pin-up cost and CO2 storage facilities. The final part of CCS project is injection and storage of CO2 to the candidate areas. Reservoir parameters which are reservoir temperature, viscosity, permeability, reservoir pressure, reservoir thickness, CO2 density mass flow rate and injection pipe diameter determine the number and cost of the injection wells.