This chapter presents an analysis of a point-of-use thermoelectric generator that is patented by one of the authors. The design, implementation and performance of the generator for powering electronic monitoring devices and charging batteries is discussed. This passive generator has no moving parts and relies on ambient air cooling. In one iteration it produces 6.9 W of steady state power using six Laird thermoelectric modules (Laird PB23 Series, HT8, 12) when placed on a 160°C steam pipe with a 30°C ambient environment ( Δ T of 130°C). The generator produced 31.2 volts (V) open circuit and 0.89 amperes (A) short circuit. It successfully powered two microcontroller-based security cameras, one with a wireless Local Area Network (LAN) and another with cellular connectivity. In another scenario, the generator produced approximately 6 W with a steam pipe temperature of 140°C and an ambient of 25°C ( Δ T of 115°C). This second system powered LED lights, a cellular-interfaced video surveillance system, and monitoring robots, while simultaneously trickle charging batteries. A third installation totally powered a stand-alone 3G web security camera system.
Part of the book: Advanced Thermoelectric Materials for Energy Harvesting Applications
PCDD/Fs are a 75-member family of toxic chemicals that include congeners (members) that have serious health effects including congeners that are classified group 1 carcinogens, endocrine disruptors and weakening or damage to the immune system. Municipal solid waste (MSW) incinerations had historically been implicated as the major source of PCDD/Fs distributed by air. As a result of awareness and legislation most European MSW incinerators were either shut down or equipped with modern air pollution control systems necessary to achieve MSW incineration with PCDD/F emissions within regulatory limits set by national and international laws (typically <0.1 ng TEQ/Nm3). There is a common belief that gasification of waste and/or biomass, unlike incineration, inherently and always achieve emission below regulatory and detectable limits. However, a review of the literature suggests that the belief that the substitution of incineration with gasification would always, or necessarily, reduce PCDD/Fs emissions to acceptable levels is overly simplistic. This chapter discusses the mechanisms of PCDD/Fs formation, the operational measures and parameter ranges that can be controlled during gasification to minimize PCDD/Fs formation, and methods for post-formation PCDD/F removal are reviewed. The purpose of this chapter is to assist researchers and practitioners in formulating waste management policies and strategies, and in conducting relevant research and environmental impact studies.
Part of the book: Gasification