Research Papers/Topics in Environmental Chemistry

Compound Parabolic Concentrators for Solar Water Heat Pasteurization: Numerical Simulation

Many people in less developed countries drink water with microbial contamination, which leads to the annual death of 5 million children. Although some people currently boil water, all microbes that cause disease in humans do not survive at temperatures >65oC, which solar water pasteurizers can easily produce. These pasteurizers are similar to box solar cookers, and typically have a small rectangular reflector. The objective of this work is to calculate the increase in output due to compound p...

Viability of Small-Scale Arsenic-Contaminated Water Purification Technologies for Sustainable Development in Pakistan

Drinking arsenic-contaminated water leads to a series of health problems that has limited development for the largely poor rural people of Pakistan who are unable to afford bottled water, centralized treatment plants, or expensive water filter systems. This paper reviews the available appropriate technologies for the removal of arsenic in drinking water to assist in just sustainable development in Pakistan. Several technologies were found to be both technically- and economically- viable and s...

Environmental Impacts of Distributed Manufacturing from 3-D Printing of Polymer Components and Products

Although additive layer manufacturing is well established for rapid prototyping the low throughput and historic costs have prevented mass-scale adoption. The recent development of the RepRap, an open source self-replicating rapid prototyper, has made low-cost 3-D printers readily available to the public at reasonable prices (

Open-Source Photometric System for Enzymatic Nitrate Quantification

Nitrate, the most oxidized form of nitrogen, is regulated to protect people and animals from harmful levels as there is a large over abundance due to anthropogenic factors. Widespread field testing for nitrate could begin to address the nitrate pollution problem, however, the Cadmium Reduction Method, the leading certified method to detect and quantify nitrate, demands the use of a toxic heavy metal. An alternative, the recently proposed Environmental Protection Agency Nitrate Reductase Nitra...

Solar photovoltaic powered on-site ammonia production for nitrogen fertilization

Ammonia synthesis is the most important step for nitrogen-fertilizer production and consumes approximately 1% of the world’s energy production and energy-related greenhouse gas emissions. In addition to the concomitant emissions caused by ammonia and nitrogen fertilizer synthesis, centrally produced fertilizer that must be distributed to farms also harms the environment because of the embodied energy of transportation. An environmentally-optimal nitrogen fertilizer system would be distribut...

Energy Payback Time of a Solar Photovoltaic Powered Waste Plastic Recyclebot System

The growth of both plastic consumption and prosumer 3-D printing are driving an interest in producing 3-D printer filaments from waste plastic. This study quantifies the embodied energy of a vertical DC solar photovoltaic (PV) powered recyclebot based on life cycle energy analysis and compares it to horizontal AC recyclebots, conventional recycling, and the production of a virgin 3-D printer filament. The energy payback time (EPBT) is calculated using the embodied energy of the materials maki...

Excess lifetime Cancer risk and Radiation Pollution hazard indices in rocks and soil of some selected mining sites in Nasarawa State, Nigeria

Radiation exposures from mining and mineral processing industries can lead to high incidence of disease conditions like nausea, lung cancer, sterility, fatigue, and diarrhoea among mineworkers. The concentration of primodial radionuclides (238U, 232Th and 40K) in some selected mining sites in Nasarawa State, Nigeria, was examined in this study. Soil and rock samples from eight different mining sites were collected and analyzed for radionuclides activity concentration by gamma ray spect...