• Energy Research

A number of wastewater treatment processes were analyzed for possible benefit in using waste heat from co-located steam-electric power plants. Three levels of treatment standards were considered, ranging from secondary treatment to stricter tertiary requirements which involve nutrient removal. Three sizes of treatment plants were analyzed, ranging from those serving 33,000 to 2,000,000 population. The processes analyzed included activated sludge, trickling filter, rotating biological contactors and the Bardenpho process. In the study, a fraction of the condenser discharge was considered mixed with primary-treated wastewater, thereby accelerating the biological secondary-treatment processes at the expense of dilution. In each case, the most cost-effective fraction of condenser flow to be utilized was determined. After treatment, a portion of the mixture would be returned to the power plant in order to recycle the corresponding condenser discharge and provide the necessary evaporative makeup for the cooling system. The balance of the mixture would constitute the water product of the treatment plant. The benefit of waste heat used to replace fuel oil in sludge digesters was also analyzed. In the case of the lowest effluent standards (Group 1), the most cost-effective secondary treatment process was activated sludge without waste-heat recycle because it is dominated by non-thermalmore » considerations. Group 2 standards were favored by rotating biological contactors with waste-heat recycle. The most advanced Group 3 standards were optimally met by the Bardenpho process, also with waste-heat recycle. In all cases, anaerobic sludge digestion with waste heat in place of fuel oil was most economical. The overall savings in levelized annual costs ranged from 1.5% for the smallest plants to 9.9% for the largest plants, by using waste heat optimally as compared with optimal systems without waste heat.« less

International Transaction Journal of Engineering, Management, & Applied Sciences & Technologies, 11, 13, 11A13E: 1-6

The relatively low temperature of thermal discharges from steam-electric power plants makes waste-heat utilization difficult without modification of the power cycle and attendant reduction in electrical energy generated. In situ beneficial use of waste heat by direct once-through condenser discharge into a municipal water supply is discussed. Computations are presented regarding the matching of flow rates, heat losses in distribution and energy savings. A number of benefits and penalties are also assessed qualitatively including legal and operational aspects and reliability. Especially attractive are improvements in electrical generating efficiency, and savings in water-heater energy. Secondary advantages include alleviation of pipe freeze up in winter and improved efficiency of slightly heated waste-water treatment. Penalties include additional pumping power for distribution in the water supply due to increased back pressure on the steam turbines which employ condensers cooled by the water they pump. Additional chlorine is also required to maintain a residual concentration in the distribution system. There may also be difficulties with public acceptance of water preheated by up to about 24/sup 0/F, especially in summer. The water supply of greater Chicago and 4880 MW(e) of colocated fossil-fired load-following generating capacity were analyzed as a hypothetical test case. It was concluded that the net annual energy savings is 23 x 10/sup 12/B, equivalent to 4 million bbl of oil, with a net savings in cost of $12./capita for the population of 4.66 m. While not developed for energy conservation purposes, three actual systems with operating experience are summarized. In order to determine feasibility of application, site-specific systems analysis is required.

Municipal solid waste (MSW) is still a serious problem in Indonesia. As well as following up on the Indonesian Government's commitment to reduce carbon emissions, a Presidential decree Perpres Number 18 of 2016 concerning the Acceleration of the Development of Waste-Based Power Plants was made. It is expected that the construction of Waste-Based Power Plants from landfills can reduce the budget deficit in handling municipal waste while maintaining environmental preservation. This research calculates the potential of landfill gas that can be produced from the landfill waste dumps of Jatibarang, as well as the capacity of electrical energy that can be produced. Furthermore, with several types of plant scenarios used, it can be seen the economic feasibility of the construction of a Waste Based Power Plant in Jatibarang landfill. The landfill gas potential and economic feasibility for this study are calculated using the Intergovernmental Panel on Climate Change (IPCC) Inventory Software and LFG-CostWeb from LandGEM. The results showed that only from the electricity sale Standard Reciprocating Engine-Generator Set project may generate a break even in the 6 yr after the operation begins and value of the net present value is USD 755 664 for 15 yr project lifetime.

In the Netherlands, roughly one and a half million tonnes of sludge end up in waste incineration plants, costing around 120 million euros. Sewage sludge is a waste stream produced at urban wastewater treatment plants and is largely being disposed of by truck trans-portation and incineration. With existing technologies sewage sludge can be dewatered up to 22 wt.% dry matter which is quite low and therefore makes current method of disposal inefficient and unsustainable.

A separate abstract was prepared for each of the 13 papers presented at the conference.

In this task we will talk over the problems in this current society from the aspect of waste production and treatment in European Union. We will classify the waste distribution to the categories, we will focus for the legislatives and the standards of waste management. Also we will preview the production statistics and waste logistic in the Czech Republic and EU. We will focus even for the waste processing like a material for the energy production and development of waste economy hypothesis. V této práci se podíváme na problematiku dnešní společnosti z hlediska produkce odpadů a jeho zpracování v rámci Evropské Unie. Poznáme rozdělení odpadů do kategorií, zaměříme se na legislativa a normy nakládání s odpady. Nahlédneme také do statistik produkce a zpracování odpadů u nás v ČR a v EU. Zaměříme se i na možnost zpracování odpadu jako suroviny pro výrobu energie a hypotézu vývoje odpadového hospodářství ČR. A

The report discusses the actual implementation of the best alternative in selling electrical power generated by an existing waste-to-energy facility, the Metro-Dade County Resources Recovery Plant. After the plant processes and extracts various products out of the municipal solid waste, it burns it to produce electrical power. The price for buying power to satisfy the internal needs of our Resources Recovery Facility (RRF) is substantially higher than the power price for selling electricity to any other entity. Therefore, without any further analysis, it was decided to first satisfy those internal needs and then export the excess power. Various alternatives were thoroughly explored as to what to do with the excess power. Selling power to the power utilities or utilizing the power in other facilities were the primary options.

During the academic year 2007/08 the Department of Applied Physics of the Faculty of Electrical Engineering and Computing conducted a public opinion survey entitled "Energy – The Present and the Future" among the student population of 1439 individuals age 18-20. The tested population consisted of the University of Zagreb nine faculties’ students. The questions in the survey covered several different energy issues, including the present and the future energy resources, the acceptability of different fuel type power plants, the environmental protection and global warming, the radioactivity, the waste issues, as well as the reliable information sources. In this paper we present the basic results of survey analysis for nuclear oriented questions. The participants are demonstrating deep lack of knowledge which results in a belief that the nuclear energy is non-economic, environmentally unacceptable and operationally unsafe source of energy, and the radioactive waste management proves to be the main source of fear from nuclear technology in general.