Pradip P. Kalbar

Weighting and Aggregation in Life Cycle Assessment: Do Present Aggregated Single Scores Provide Correct Decision Support?

This study investigates the prevailing practice of obtaining single scores in life cycle assessment (LCA) and identifies potential lacunas in impact assessment methodology related to the results of aggregation into endpoints and single scores. In order to conduct this investigation, a detailed approach was adopted to facilitate identification of three main problems related to the single†score calculation approach. The prevailing ReCiPe single†score calculation method does not account for either the effect of so†called dominating alternatives (i.e., alternatives having high values across all endpoints) or the interdependency of the indicators being aggregated. It was also found that the simple linear weighted sum method, presently used for obtaining single scores, is not capable of accounting for the effect of weighting schemes and thus cannot realistically represent stakeholders’ perspectives. Finally, we propose a distance†based multiple attribute decision†making method for use in obtaining single scores. This method was found to be more suitable, given that it takes into account the weighting schemes and types of indicators in the process of estimating single scores. The new single†score calculation method proposed here is considered ideal for environmental decision†making problems in the context of life cycle sustainability assessment. Thus, it is also ideal for situations in which more†complex decision†making situations will emerge by combining LCA indicators (midpoints or endpoints) with other indicators representing the performance of a system from economic and social perspectives.

Personal Metabolism (PM) coupled with Life Cycle Assessment (LCA) model: Danish Case Study

Sustainable and informed resource consumption is the key to make everyday living sustainable for entire populations. An intelligent and strategic way of addressing the challenges related with sustainable development of the everyday living of consumers is to identify consumption-determined hotspots in terms of environmental and health burdens, as well as resource consumptions. Analyzing consumer life styles in terms of consumption patterns in order to identify hotspots is hence the focus of this study. This is achieved by taking into account the entire value chain of the commodities consumed in the context of environmental and human health burdens, as well as resource consumptions. A systematic commodity consumption, commodity disposal, and life style survey of 1281 persons living in urbanized Danish areas was conducted. The findings of the survey showed new impact dimensions in terms of Personal Metabolism (PM) patterns of residents living in urbanized areas of Denmark. Extending the PM analysis with Life Cycle Assessment (LCA) provided a clear picture of the per capita environmental and human health burdens, as well as resource consumptions, and the exact origin hereof. A generic PM-LCA Model for all the 1281 persons was set-up in Gabi 6. The assessment results obtained applying the model on all 1281 personal consumption scenarios yielded the 1281 Personal Impact Profiles (PIPs). Consumption of food and energy (electricity and thermal energy) proved to be the primary impact sources of PM, followed by transport. The PIPs further revealed that behavioral factors (e.g. different diets, use of cars, household size) affect the profiles. Hence, behavioral changes are one means out of many that humanity will most likely have to rely on during the sustainable development process. The results of this study will help the Danish and other comparable populations to identify and prioritize the steps towards reducing their environmental, human health, and resource consumption burdens.

Rejuvenation of Rivers and Lakes in India: Balancing Societal Priorities with Technological Possibilities

In the light of shortage of water in several parts of the World, especially in the developing country like India and in the context of the prevailing policy of accelerating growth through industrialization, there is an eminent need for devising newer approaches of water management. Various innovative successful approaches have been discussed which balanced societal priorities with feasible treatment technologies particularly focusing on natural treatment systems (NTSs). It has been argued that the NTSs can be effectively combined with advanced tertiary treatment alternatives and resulting high quality treated effluents can be gainfully recycled into production and sanitation applications. The dimensions of sustainability, stakeholder satisfaction, appropriate technologies, regulatory frameworks, governing institutions, and financial models have also been discussed.

Life cycle-based environmental assessment of municipal wastewater treatment plant in India

The environmental footprint of wastewater treatment plant (WWTP) can be assessed using a life cycle assessment (LCA) approach. Life cycle impacts are computed according to the CML 2 baseline 2000 methodology. An LCA study was carried out for WWTP treating municipal wastewater. Results show that the construction phase contributes to nearly 1% for the impacts when compared to overall life cycle impact of the plant and hence can be neglected. This work attempts to achieve significantly transparent results using LCA in limited availability of data. Original data was collected and analysed by the authors as part of this study through visits to wastewater treatment plants and on-site surveys. The lack of national life cycle inventories and computerised databases in India limits the wide application of LCA in the context of environmental decision making.

WW LCI v2: A second-generation life cycle inventory model for chemicals discharged to wastewater systems

We present a second-generation wastewater treatment inventory model, WW LCI 2.0, which on many fronts represents considerable advances compared to its previous version WW LCI 1.0. WW LCI 2.0 is a novel and complete wastewater inventory model integrating WW LCI 1.0, i.e. a complete life cycle inventory, including infrastructure requirement, energy consumption and auxiliary materials applied for the treatment of wastewater and disposal of sludge and SewageLCI, i.e. fate modelling of chemicals released to the sewer. The model is expanded to account for different wastewater treatment levels, i.e. primary, secondary and tertiary treatment, independent treatment by septic tanks and also direct discharge to natural waters. Sludge disposal by means of composting is added as a new option. The model also includes a database containing statistics on wastewater treatment levels and sludge disposal patterns in 56 countries. The application of the new model is demonstrated using five chemicals assumed discharged to wastewater systems in four different countries. WW LCI 2.0 model results shows that chemicals such as diethylenetriamine penta (methylene phosphonic acid) (DTPMP) and Diclofenac, exhibit lower climate change (CC) and freshwater ecotoxicity (FET) burdens upon wastewater treatment compared to direct discharge in all country scenarios. Results for Ibuprofen and Acetaminophen (more readily degradable) show that the CC burden depends on the country-specific levels of wastewater treatment. Higher treatment levels lead to lower CC and FET burden compared to direct discharge. WW LCI 2.0 makes it possible to generate complete detailed life cycle inventories and fate analyses for chemicals released to wastewater systems. Our test of the WW LCI 2.0 model with five chemicals illustrates how the model can provide substantially different outcomes, compared to conventional wastewater inventory models, making the inventory dependent upon the atomic composition of the molecules undergoing treatment as well as the country specific wastewater treatment levels.