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.
View Article and Find Full Text PDFAging infrastructure, increasing environmental regulations, and receiving water environment issues stem the need for advanced wastewater treatment processes across the world. Advanced wastewater treatment systems treat wastewater beyond organic carbon removal and aim to remove nutrients and recover valuable products. While the removal of major nutrients (carbon, nitrogen, and phosphorus) is essential for environmental protection, this can only be achieved through energy-, chemical-, and cost-intensive processes in the industry today, which is an unsustainable trend, considering the global population growth and rapid urbanization.
View Article and Find Full Text PDFSustain Cities Soc
January 2021
Recent outbreaks have constantly disrupted our global economy and public health in numerous ways, impacting efficiency and prosperity across all sectors. This article focuses on the impacts of outbreaks (epidemics and pandemics) on water - wastewater utilities and water infrastructure and critically evaluates the issues underlining their impact on economic development and highlights the need for preparedness. A perspective on water infrastructure and industry-related impact on our society and economic development in the wake of the pandemic, COVID-19, is presented.
View Article and Find Full Text PDFIn this research, low strength synthetic wastewaters with chemical oxygen demand less than 300 mg L were treated at different concentrations in a bioelectrochemical desalination process. A process optimization model was utilized to study the performance of the photosynthetic bioelectrochemical desalination process. The variables include substrate (chemical oxygen demand) concentration, total dissolved solids, and microalgae biomass concentration in the cathode chamber.
View Article and Find Full Text PDFThis 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.
View Article and Find Full Text PDFClostridium, Tetrathiobacter and Desulfovibrio species are identified as suitable biocatalysts for treating organic-rich and sulfate-laden wastewater. Results from this study show that the power generation was much higher under alkaline conditions, i.e.
View Article and Find Full Text PDFThis 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.
View Article and Find Full Text PDFThis study reports an investigation of the concept, application and performance of a novel bioelectrochemical nitritation-anammox microbial desalination cell (MDC) for resource-efficient wastewater treatment and desalination. Two configurations of anammox MDCs (anaerobic-anammox cathode MDC (AnAMDC) and nitration-anammox cathode MDC (NiAMDC)) were compared with an air cathode MDC (CMDC), operated in fed-batch mode. Results from this study showed that the maximum power density produced by NiAMDC (1,007 mW/m) was higher than that of AnAMDC (444 mW/m) and CMDC (952 mW/m).
View Article and Find Full Text PDFAn update on the current research and development of wetland treatment technologies for wastewater treatment is provided in this paper. This article focuses on wetland applications in wastewater treatment (as an advanced treatment unit or a decentralized system), and nutrient and pollutant removal (metals, industrial and emerging pollutants including pharmaceutical compounds). A summary of studies involving the effects of vegetation, wetland design and operation, modeling, hybrid and innovative systems, landfill leachate treatment, and pathogen removal is also included.
View Article and Find Full Text PDFThis article provides an update on the wastewater treatment technologies, which utilize natural processes or passive components to remove various pollutants. The focus is on the wetland systems and their applications in wastewater treatment (as an advanced treatment unit or a decentralized system), and nutrient and pollutant removal (heavy and hazardous metals, industrial and emerging pollutants including pharmaceutical and personal care products and endocrine disrupting chemicals). A summary of studies involving the effects of vegetation, wetland design and operation, modeling, hybrid and innovative systems, storm water treatment, sludge treatment, landfill leachate treatment, and pathogen removal is also included.
View Article and Find Full Text PDFAn update on the current research and development of the treatment technologies, which utilize natural processes or passive components in wastewater treatment, is provided in this paper. The main focus is on wetland systems and their applications in wastewater treatment (as an advanced treatment unit or decentralized system), nutrient and pollutant removal (metals, industrial and emerging pollutants including pharmaceutical compounds). A summary of studies involving the effects of vegetation, wetland design and modeling, hybrid and innovative systems, storm water treatment and pathogen removal is also included.
View Article and Find Full Text PDFDesalination technologies have evolved and advanced rapidly along with increasing water demands around the world since 1950s. Many reviews have focused on the techno-economic and environmental and ecological issues of the desalination technologies and emphasized the feasibility of desalination industry as an alternative to meet the water demands in many water scarce regions. Despite these efforts, many perceptions about desalination processes hinder their applications for potential water supplies.
View Article and Find Full Text PDFThis paper provides a review of the treatment technologies, which utilize natural processes or passive components in wastewater treatment. In particular, this paper primarily focuses on wetland systems and their applications in wastewater treatment (as an advanced treatment unit or decentralized system), nutrient and pollutant removal (single and multiple pollutants, and metals), and emerging pollutant removal (pharmaceuticals). A summary of studies involving the plant (vegetation) effects, wetland design and modeling, hybrid and innovative systems, storm water treatment and pathogen removal is also included.
View Article and Find Full Text PDFThis study reports on the effects of direct pulse sonication and the type of alcohol (methanol and ethanol) on the transesterification reaction of waste vegetable oil without any external heating or mechanical mixing. Biodiesel yields and optimum process conditions for the transesterification reaction involving ethanol, methanol, and ethanol-methanol mixtures were evaluated. The effects of ultrasonic power densities (by varying sample volumes), power output rates (in W), and ultrasonic intensities (by varying the reactor size) were studied for transesterification reaction with ethanol, methanol and ethanol-methanol (50%-50%) mixtures.
View Article and Find Full Text PDFThis study describes the use of microwaves (MW) for enhanced extractive-transesterification of algal lipids from dry algal biomass (Chlorella sp.). Two different single-step extractive-transesterification methods under MW irradiation were evaluated: (1) with ethanol as solvent/reactant and sodium hydroxide catalyst; and (2) with ethanol as reactant and hexane as solvent (sodium hydroxide catalyst).
View Article and Find Full Text PDFEnviron Sci Process Impacts
December 2013
Current microbial desalination cell (MDC) performances are evaluated with chemical catalysts such as ferricyanide, platinum catalyzed air-cathodes or aerated cathodes. All of these methods improve power generation potential in MDCs, however, they are not preferable for large scale applications due to cost, energy and environmental toxicity issues. In this study, performance of microbial desalination cells with an air cathode and an algae biocathode (Photosynthetic MDC - PMDC) were evaluated, both under passive conditions (no mechanical aeration or mixing).
View Article and Find Full Text PDFIn this study, the feasibility of the direct contact membrane distillation (DCMD) process to recover arsenic, uranium and fluoride contaminated saline ground waters was investigated. Two types of membranes (polypropylene, PP; and polytetrafluoroethylene, PTFE) were tested to compare the permeate production rates and contaminant removal efficiencies. Several experiments were conducted to study the effect of salts, arsenic, fluoride and uranium concentrations (synthetic brackish water with salts: 1000-10,000 ppm; arsenic and uranium: 10-400 ppb; fluoride: 1-30 ppm) on the desalination efficiency.
View Article and Find Full Text PDFThe effect of microwave irradiation on the simultaneous extraction and transesterification (in situ transesterification) of dry algal biomass to biodiesel was investigated. A high degree of oil/lipid extraction from dry algal biomass and an efficient conversion of the oils/lipids to biodiesel were demonstrated in a set of well-designed experimental runs. A response surface methodology (RSM) was used to analyze the influence of the process variables (dry algae to methanol (wt/vol) ratio, catalyst concentration, and reaction time) on the fatty acid methyl ester conversion.
View Article and Find Full Text PDFThis study demonstrated a one-step process for direct liquefaction and conversion of wet algal biomass containing about 90% of water to biodiesel under supercritical methanol conditions. This one-step process enables simultaneous extraction and transesterification of wet algal biomass. The process conditions are milder than those required for pyrolysis and prevent the formation of by-products.
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