In an effort to obtain the most accurate climate change impact assessment, greenhouse gas (GHG) accounting is evolving to include life-cycle thinking. This study (1) identifies similarities and key differences between GHG accounting and life-cycle assessment (LCA), (2) compares them on a consistent basis through a case study on a waste management business unit. First, GHG accounting is performed. According to the GHG Protocol, annual emissions are categorized into three scopes: direct GHG emissions (scope 1), indirect emissions related to electricity, heat and steam production (scope 2) and other indirect emissions (scope 3). The LCA is then structured into a comparable framework: each LCA process is disaggregated into these three scopes, the annual operating activities are assessed, and the environmental impacts are determined using the IMPACT2002+ method. By comparing these two approaches it is concluded that both LCA and GHG accounting provide similar climate change impact results as the same major GHG contributors are determined for scope 1 emissions. The emissions from scope 2 appear negligible whereas emissions from scope 3 cannot be neglected since they contribute to around 10% of the climate change impact of the waste management business unit. This statement is strengthened by the fact that scope 3 generates 75% of the resource use damage and 30% of the ecosystem quality damage categories. The study also shows that LCA can help in setting up the framework for a annual GHG accounting by determining the major climate change contributors.

Laboratory experiments were conducted to determine the potential for removing 1,2-dichlorobenzene (1,2-DCB) in gaseous phase by biofiltration. Experiments were carried out over 8 months in a steel tank (0.45 m 3 ) using an organic filter medium composed of peat, maple wood chips, chicken manure and 1,2-DCB-contaminated soil. During the first 6 months, the biofilter was operated without injecting 1,2-DCB in order to characterize the physicochemical, mechanical and microbiological properties of the filter bed. The results revealed that it is an excellent medium for both microbial development (up to 10 9 cells g −1 dry soil for heterotrophic bacteria) and long-term stability with a limited drop of pressure (30 cm of water) and no clogging. Over the final 2 months, the biofilter treated air laden with 1,2-DCB (0.30 and 0.75 g m −3 ) and the maximum elimination capacity reached was 9 g m −3 h −1 (inlet load of 13 g m −3 h −1 ), which represented 69% efficiency. Elimination performance was strongly dependent upon inlet concentration, sorption/desorption and biodegradation phenomena occurring in the filter medium. Sorption/desorption and biodegradation mechanisms during the start-up period were characterized using the elimination efficiency (%). At the beginning of the 1,2-DCB injection, the microorganisms were strongly impacted and sorption/desorption phenomena prevailed. With the decrease of the inlet concentration, biodegradation progressively increased to become the most important mechanism. It was concluded that biofiltration possesses an excellent potential for treating volatile chlorinated benzene, known to be recalcitrant to biodegradation.