• Energy Research

The most common system for flue gas desulfurization (FGD) is the wet scrubbing process in which, the contact between the flue gases to be treated and an alkaline sorbent such limestone is realized with the correspondent production of gypsum. The production of gypsum represent a perfect example of how is possible to obtain a new product for the market starting from the need of environmental protection (the sulphur dioxide (SO2) removal). Today, limestone is ground in long drum mill reaching a size in the range 5–10 mm. With the intent of increasing the specific surface area of limestone and consequently the gypsum production, the raw limestone was treated in a high-energy mill. The performance of such micronized limestone in terms of gypsum production and SO2 removal were then evaluated by means of a bench scale desulfurization test. Subsequently, a feasibility study with the goal to verify the possible advantages simulating the application of the micronized limestone on a full-scale Waste-to-Energy (WtE) plant was realized. Results showed how the micronization process occurred securely, with a greater production of gypsum and better performance in terms of SO2 removal. Additionally, the micronization solutions tested in the present study showed the suitability also from economic and environmental point of view. Since there are many power plants or WtE plants worldwide and, in many cases, they adopt a wet FGD, this study may be attractive for plant operators. The greater production of gypsum through the use of micronized limestone may help reduce the consumption of raw materials, which increased in recent years due to growing demand of the building industry. © 2017 Institution of Chemical Engineers

The perceived risks and benefits of electric power alternatives were used to explore the context of attitudes toward nuclear power. Supporters and opponents of nuclear power responded to thirty-three items which referred to five categories of energy issue: the production potential of electric, risks of those technologies, power generation technologies, energy conservation, comparisons of risks among technologies and comparisons between risks and benefits of each technology. The results are summarized. The nuclear supporters studied here do favor nuclear power. However, they believe that there are limited prospects for contributions from solar, wind and hydroelectric technologies. They also believe that there are serious disadvantages to conservation. Nuclear opponents, on the other hand, disagree that there are such limited prospects for solar and wind, although they are neutral on the prospects for increased hydro capacity. They also do not believe that conservation necessarily poses serious adverse consequences either for themselves or others.

This study assessed the viability of an anion-exchange microbial fuel cell (MFC) for extracting electricity from palm oil mill effluent (POME), a major pollutant in palm-oil producing regions due to increasing demand. The MFC incorporated a tubular membrane electrode assembly (MEA) with an air core, featuring a carbon-painted carbon-cloth cathode, an anion exchange membrane (AEM), and a nonwoven graphite fabric (NWGF) anode. An additional carbon brush (CB) anode was placed adjacent to the tubular MEA. The MFC operated under semi-batch conditions with POME replacement every 7 days. Results showed superior performance of the AEM, with the highest power density (Pmax) observed in POME-treated MFCs. Current and power density increased with CB addition; the best chemical oxygen demand (COD) removal efficiency reached 73 %, decreasing from 1249 to 332 mg/L with three CBs. The Pmax was 0.18 W/m-2(-|-) with 1000 mg/L COD and three CBs, dropping to 0.0031 W/m-2(-|-) without CB and at 410 mg/L COD. Anode resistance, calculated using organic matter supplementation, COD, and anode surface area, decreased with increased COD or surface area, improving electricity production. AEM and CB compatibility synergistically enhanced MFC performance, offering potential for POME wastewater treatment and energy recovery.

Municipal solid waste (MSW) combustion with energy recovery, commonly called waste-to-energy (WTE), was adopted by many US communities during the 1980s to manage their growing quantities of MSW. Although less than one percent of all US MSW was burned to retrieve its heat energy in 1970, WTE grew to account for 16 percent of MSW in 1990, and many experts forecasted that WTE would be used to manage as much as half of all garbage by the turn of the century. However, the growth of WTE has been reduced in recent years by project cancellations. This study takes an in-depth look at the socioeconomic factors that have played a role in the decisions of communities that have considered WTE as a component of their solid waste management strategies. More specifically, a three-pronged approach is adopted to investigate (1) the relationships between a municipality`s decision to consider and accept/reject WTE and key socioeconomic parameters, (2) the potential impacts of recent changes in financial markets on the viability of WTE, and (3) the WTE decision-making process and the socioeconomic parameters that are most important in the municipality`s decision. The first two objectives are met by the collection and analysis of aggregate datamore » on all US WTE initiatives during the 1982 to 1990 time frame. The latter objective is met by way of four in-depth case studies -- two directed at communities that have accepted WTE and two that have cancelled WTE projects.« less

Attempts to solve the problem of high-level waste disposal including the spent fuel from nuclear power plants have been made in the Czech Republic for over the 10 years. Already in 1991 the Ministry of Environment entitled The Czech Geological Survey to deal with the siting of the locality for HLW disposal and the project No. 3308 ''The geological research of the safe disposal of high level waste'' had started. Within this project a sub-project ''A selection of perspective HLW disposal sites in the Bohemian Massif'' has been elaborated and 27 prospective areas were identified in the Czech Republic. This selection has been later narrowed to 8 areas which are recently studied in more detail. As a parallel research activity with siting a granitic body Melechov Massif in Central Moldanubian Pluton has been chosen as a test site and the 1st stage of research i.e. evaluation and study of its geological, hydrogeological, geophysical, tectonic and structural properties has been already completed. The Melechov Massif was selected as a test site after the recommendation of WATRP (Waste Management Assessment and Technical Review Programme) mission of IAEA (1993) because it represents an area analogous with the host geological environment for the future HLW and spent fuel disposal in the Czech Republic, i.e. variscan granitoids. It is necessary to say that this site would not be in a locality where the deep repository will be built, although it is a site suitable for oriented research for the sampling and collection of descriptive data using up to date and advanced scientific methods. The Czech Republic HLW and spent fuel disposal programme is now based on The Concept of Radioactive Waste and Spent Nuclear Fuel Management (''Concept'' hereinafter) which has been prepared in compliance with energy policy approved by Government Decree No. 50 of 12th January 2000 and approved by the Government in May 2002. Preparation of the Concept was required, amongst other reasons in connection with preparations for the Czech Republic's ...

A project to design, construct, and operate a pressurized biomass gasification plant in Hawaii will begin in 1991. Negotiations are underway with the United States Department of Energy (DOE) which is co-funding the project with the state of Hawaii and industry. The gasifier is a scale-up of the pressurized fluidized-bed RENUGAS process developed by the Institute of Gas Technology (IGT). The project team consists of Pacific International Center for High Technology Research (PICHTR), Hawaii Natural Energy Institute (HNEI) of the University of Hawaii, Hawaiian Commercial and Sugar Company (HC S), The Ralph M. Parsons Company, and IGT. The gasifier will be designed for 70 tons per day of sugarcane fiber (bagasse) and will be located at the Paia factory of HC S on the island of Maui. In addition to bagasse, other feedstocks such as wood, biomass wastes, and refuse-derived-fuel may be evaluated. The demonstration plant will ultimately supply part of the process energy needs for the sugar factory. The operation and testing phase will provide process information for both air- and oxygen-blown gasification, and at both low and high pressures. The process will be evaluated for both fuel gas and synthesis gas production, and for electrical power production with advanced power generation schemes. 6 refs., 3 figs., 1 tab.

The City of Geneva, population 159,000 is the administrative center of the Canton of Geneva, population 340,000. The Canton owns a number of facilities for the treatment of waste. Geneva's chief waste treatment facility is the Cheneviers Incinerator. Two Von Roll integrated boiler incinerator furnaces have a rated capacity of 200 metric tons (220 short tons) per day each. Superheated steam at 360/sup 0/C and 32.4 bars (32 atm) powers a 6200 kW turbo-generator unit. The electricity is sold to the cantonal grid. Total incinerable waste in the Canton of Geneva has varied from 120,000 to 130,000 metric tons (132,000 to 144,000 short tons) annually during the last five years. For the last two years, total per capita tonnage have been declining. Per capita incinerable waste was 363 kilograms (800 lbs) in the year 1975, of which 257 kilograms (606 lbs) were household waste. Eighty-seven thousand, five hundred metric tons (96,386 short tons) of this waste was burned in the Cheneviers Incinerator in 1975. The remainder was landfilled, due to the lack of capacity at the incinerators. The system which began operating in 1966, cost approximately 40 million Swiss Francs ($9.3 million; 1965 or $23 million; 1976). Three-quarters of this sum was for land, buildings, construction, and equipment. A large station and dock for the transfer of waste accounted for the remainder. The Von Roll design ofthis plant is now out of date. Extensive modifications were made to correct corrosion problems in the furnace.