Environmental impact assessment of biomass supported electricity generation for sustainable rural energy systems - A case study of Grenada County, Mississippi, USA.

Fossil fuels have been the major source of electricity supply in the United States of America (USA) for many decades. While a significant shift has occurred from coal-dominated supply to natural gas and renewable source based supplies in recent decades, there is still large potential to improve biomass supported electricity contribution in rural communities, which depend majorly on forest-related activities. Wood waste, an underutilized renewable resource, has the potential for electricity generation in rural areas to reduce the contribution of electricity generated from fossil fuels and assist in greenhouse gas savings. In this study, a life cycle assessment approach was used to estimate the emissions of electricity generated by wood residues in a rural community (Grenada County, Mississippi (MS), USA) and compared with those emissions from the recent electricity mix (2018), a previous electricity mix (2010) supply, along with natural gas (NG) and coal (Bituminous Coal, BC) based electricity generation options. A significant reduction (85.9-94.6%) in global warming impact was observed when compared with BC, NG and grid supplied electricity for years 2010 and 2018. When compared to the current electricity mix at the grid (2018), acidification, eutrophication, respiratory effects and smog formation showed higher emissions ranging from 30.8% to 72.4%. The sensitivity analysis showed an improvement in emissions savings with increased biomass to power conversion efficiency (40%), lower moisture content of the biomass (0%, bone dry biomass), and reduced transportation distance (35 km). This study showed an improvement in the electricity mix supplied to Grenada county, MS, which implies sustainable development opportunities for promoting energy security in rural communities with forest-based industries.

Wetlands for environmental protection.

This article presents an update on the research and practical demonstration of wetland-based treatment technologies for protecting water resources and environment covering papers published in 2019. Wetland applications in wastewater treatment, stormwater management, and removal of nutrients, metals, and emerging pollutants including pathogens are highlighted. A summary of studies focusing on the effects of vegetation, wetland design and operation strategies, and process configurations and modeling, for efficient treatment of various municipal and industrial wastewaters, is included. In addition, hybrid and innovative processes with wetlands as a platform treatment technology are presented.

Wetlands for wastewater treatment.

This article presents an update on the research and practical demonstration of wetland treatment technologies for wastewater treatment. Applications of wetlands in wastewater treatment (as an advanced treatment unit or a decentralized system) and stormwater management or treatment for nutrient and pollutant removal (metals, industrial and emerging pollutants including pharmaceutical compounds and pathogens) are highlighted. A summary of studies involving the effects of vegetation, wetland design and operation, and configurations for efficient treatment of various municipal and industrial wastewaters is also included. PRACTITIONER POINTS: Provides an update on current research and development of wetland technologies for wastewater treatment. Effects of vegetation, pathogens removal, heavy metals and emerging pollutants removal are included. Wetland design and operation is a key factor to improve water quality of wetland effluent.