Environmental evaluation of waste treatment scenarios for the towns Khanty-Mansiysk and Surgut, Russia.

Khanty-Mansiysk Autonomous Okrug - Ugra in Siberia has recently started to play a major role in the Russian economy because key oil and gas extraction sites are located in this region. As a result, the extensions of infrastructure and higher incomes have been leading to an accelerated population growth and consequent increase in the generation of solid household waste. The current methods of waste disposal have now reached their limits, especially in the towns Khanty-Mansiysk and Surgut. The key objectives of this study were to identify the influence of waste composition and transport routes on the life cycle assessment (LCA) results and to assess the current waste treatment option for solid household waste and to compare it with proposed scenarios. Furthermore, recommendations for an optimal use of LCA within a decision-making process for a waste management plan are presented. LCA methodology was used to evaluate different waste management scenarios such as landfilling and incineration. One result was that the options 'incineration with recycling' and 'anaerobic mechanical-biological treatment with recycling' demonstrated lower environmental impact in both Khanty-Mansiysk and Surgut. Another finding was that there were hardly any differences in the ranking of the scenarios for Surgut and Khanty-Mansiysk. However, the special socio-cultural circumstances and location of each town have to be considered seriously in the development of a sustainable waste management plan.

Environmental assessment of the milk life cycle: the effect of packaging selection and the variability of milk production data.

Milk is a very important part of our diet, which is why there is a wide variety of packaging alternatives with considerable local variants on the market. This study assesses the environmental impact of the commonest packaging options on the Spanish market and evaluates (from the point of view of global warming and acidification) the production of the various packaging materials and sizes and their final disposal (landfilling, incineration and recycling). For the two indicators studied (global warming and acidification) larger aseptic carton packages and recycling disposal have the best environmental impact. The global warming and acidification potential of the milk life cycle were also studied: milk production, transport (local conditions), packaging production and packaging disposal. Of the two indicators studied, the milk production stage has the largest impact on the milk life cycle. It should be taken into account that the impact of the milk production stage can vary considerably and has a significant influence on the global warming and acidification potential of the milk life cycle.

Environmental assessment of urban wastewater reuse: treatment alternatives and applications.

The main function of a Wastewater Treatment Plant is to minimize the environmental impact of discharging untreated water into natural water systems. Also a Wastewater Treatment Plant may get a resource from wastewater carrying out a tertiary treatment on the treated wastewater which can be reused in non-potable applications. Water reuse strategies are intended to address the problem of water scarcity without aggravating other environmental problems, thus reflecting the need of their environmental assessment. In this paper we used Life Cycle Assessment to evaluate different disinfection treatments (chlorination plus ultraviolet treatment, ozonation and ozonation plus hydrogen peroxide) and to assess the environmental advantages and drawbacks of urban wastewater reuse in non-potable applications. To do so, we compared the environmental impacts of producing 1m(3) of water for non-potable uses from reclaimed water, potable water and desalinated water sources. The calculation has used current operating data from a Wastewater Treatment Plant located in the Mediterranean area, although the results can be applied to any other plant with similar technology. The ozonation and ozonation plus hydrogen peroxide disinfection treatment technologies have similar environmental profiles. However most of the indicators are about 50% higher than the ultraviolet disinfection except for the acidification (100% higher) and photochemical oxidation (less than 5%). Non-potable uses (both agricultural and urban uses) of reclaimed water have environmental and economical advantages. Reuse of treated wastewater is particularly beneficial when it can replace desalinated water. Consequently, reclaimed water should be promoted for non-potable uses, when there is scarcity of freshwater.

LCA as a decision support tool for the environmental improvement of the operation of a municipal wastewater treatment plant.

Life cycle assessment (LCA) methodology is used to evaluate the environmental profile of a product or process from its origin to its final destination. In this paper we used LCA to evaluate the current situation of a wastewater treatment plant and identify improvement alternatives. Currently, the highest environmental impacts are caused by the stages of the plant with the highest energy consumption, the use of biogas from anaerobic digestion (95% burned in torch) and the final destination of the sludge (98.6% for agricultural use and 1.4% for compost). We propose four alternatives for biogas applications and five alternatives for sludge applications and compare them to the current situation. The alternatives were incorporated in a decision support system to identify and prioritize the most positive environmental option. Using biogas to produce electricity or a combination of electricity and heat provided the best environmental options since the energy produced would be enough to supply all the stages of the plant, thus reducing their environmental impact. The best environmental option for the final destination of the sludge is to combine the current situation (fertilizer replacement) with use of the sludge in a cement plant (as a replacement for fuel and raw material).

Health risk assessment of emissions of dioxins and furans from a municipal waste incinerator: comparison with other emission sources.

The aim of this study was to calculate the incremental lifetime-risk to dioxins and furans (PCDD/Fs) for the population living in the surroundings of a municipal solid waste incinerator (MSWI), as well as to establish the potential reduction on human health risks as a consequence of the adaptation to the EU legislation on pollutant emissions from the MSWI stack. Analytical and modelled results were obtained. PCDD/F concentrations in environmental media were determined by means of a simple-compartment-multimedia model (air-soil-vegetation model). Predicted and measured PCDD/F concentrations in soils and vegetation were compared, and the effects of MSWI emissions in the environmental media were determined. Human health risks due to PCDD/F emissions from the MSWI were also estimated based on I-TEQ measured and modelled in various environmental media. Cancer risks due to PCDD/F emissions of the plant were 1.07E-07 and 3.08E-09, before and after installation of the clean air system, respectively. On the other hand, cancer risks due to other PCDD/F emission sources in the area were 5.54E-06 and 1.86E-06. Total PCDD/F cancer risks (including those from diet) for the population living in the vicinity of the MSWI were 1.3E-04 and 4.25E-05, respectively (67.6% of reduction). Hazard ratio for total PCDD/F exposure (including diet) decreased during the last 5 years from 1.16 to 0.38. The above data show that other emission sources of PCDD/Fs also have a notable environmental impact on the area under direct influence of the MSWI.