• Energy Research

The potentials for energy consumption, conservation, and recovery at municipal wastewater treatment plants are relatively small compared to the national energy figures. Nevertheless they are significant, particularly to local owners and operators. Estimates of energy consumption, as well as opportunities for conservation and energy recovery in municipal wastewater treatment operations, are reviewed. The relationship between energy conservation and aquaculture based wastewater treatment systems is also introduced. Finally, current DOE activities in this area are presented.

This memorandum discusses five key issues that initial interviews have brought into focus: The preoccupation of the public with nuclear waste disposal, the credibility of public opinion polls addressing nuclear power, the unlikelihood of dramatic change in opinion by nuclear critics, difficulties in communicating technical concepts, and the problem of focussing narrowly or broadly on policy issues.

The design and operation of the demonstration plant facilities at Tarleton State University to produce methane in a single stage anaerobic digester are described. A combination of manures from hogs and poultry are used as feedstock. Uses for the methane, cost of the digester, and value of the energy produced are discussed. During the 21 months of operation, 310 people have visited the project. (DMC)

The Geothermal Development Program at Lawrence Livermore Lboratory has produced several novel expanders for liquids of low to medium temperatures (approx. 180/sup 0/C). A unique radial outflow reaction turbine (RORT) has been developed and laboratory-tested; results indicate that 50% engine efficiency is achievable. This work has led to a new concept called the velocity pump reaction turbine (VPRT), which could significantly increase the gross engine efficiency of the RORT, VPRT and its modifications are a unique family of turbines created specifically for expanding liquids to produce shaft work at potential engine efficiencies of up to 70%. Such devices, if used between the two separation stages of a double-flash system, could increase the overall power output by 15 to 20%, reducing power costs by at least 10% for about a 3% increase in capital costs. Geothermal applications are discussed with emphasis on geopressured resources. Also, these machines are suitable for utilizing solar heated fluids and waste heat sources from industrial processes.

Inadequate disposal of Municipal Solid Waste (MSW) is one of the greatest environmental issues confronted nowadays. One of the techniques used for its final disposal is incineration, otherwise known as mass burning. Although this procedure remains very controversial in Brazil, some recent studies published in Europe reveal a large amount of misinformation about it. It has been widely used in European countries, Japan, and a few U.S. cities and has been increasingly and significantly adopted in China. Therefore, this article aims to carry out a literature review on the evolution of waste-to-energy recovery from Municipal Solid Waste (MSW) worldwide and the progress of mass-burning technologies, particularly in the Brazilian context. For such a purpose, global scientific databases were selected and some of their results allowed us to present how the main WtE recovery technologies function, as well as their benefits and impacts. Moreover, it was possible to systematize the main regulatory frameworks on the theme in Brazil and to reveal the country’s electricity generation capacity, in addition to depicting the progress of Waste-to-Energy Plants (WtEPs) undergoing licensing processes in the state of São Paulo.

This report presents the results of an experimental program to demonstrate the suitability of the Battelle High Throughput Gasification Process to non-wood biomass fuels. An extensive data base on wood gasification was generated during a multi-year experimental program. This data base and subsequent design and economic analysis activities led to the discussion to study the gasification character of other fuels. The specific fuel studied was refuse derived fuel (RDF) which is a prepared municipal solid waste (MSW). The use of RDF, while providing a valuable fuel, can also provide a solution to MSW disposal problems. Gasification of MSW provides advantages over land fill or mass burn technology since a more usable form of energy, medium Btu gas, is produced. Land filling of wastes produces no usable products and mass burning while greatly reducing the volume of wastes for disposal can produce only steam. This steam must be used on site or very nearby this limiting the potential locations for mass burn facilities. Such a gas, if produced from currently available supplies of MSW, can contribute 2 quads to the US energy supply. 3 refs., 12 figs., 7 tabs.

Dutchess County initiated development of a long-range master plan for Solid Waste Management in 1971. The plan included development of a resource recovery facility to service the municipalities in the County population center. Based on early recommendations, a pyrolysis facility employing Purox technology was to be implemented. A feasibility study, paid for by County funds was completed in 1975. The study provided siting recommendations, estimation of available waste, and preliminary facility design. Because of various considerations, the project was not developed. Under the Department of Energy grant, the County reassessed the feasibility of a resource recovery facility, with emphasis on confirming previous conclusions supporting the Purox technology, waste availability, energy recovery and sale and siting of the plant. The conclusions reached in the new study were: a resource recovery facility is feasible for the County; sufficient waste for such a facility is available and subject to control; While Purox technology was feasible it is not the most appropriate available technoloy for the County; that mass burning with steam recovery is the most appropriate technology; and that resource recovery while presently more expensive than landfilling, represents the only cost effective, energy efficient, and environmentally sound way to handle the solid waste problem in the County.

Delays in the start-up of the RefCOM facility in Pompano Beach, Florida, are outlined. The most serious delays involved problems with the screw conveyors. After many modifications had proven futile, it was decided that they were not applicable to the system and the screw conveyors were replaced with a rotary feeder. An itemized, chronological list of all plant modifications including the cost of labor and materials are presented in this report. Diagrams and daily work sheets are included. (DMC)

This ash study investigated the beneficial use of municipal waste combustion combined ash from the H-POWER facility in Oahu. These uses were grouped into intermediate cover for final closure of the Waipahu landfill, daily cover at the Waimanalo Gulch Landfill, and partial replacement for aggregate in asphalt for road paving. All proposed uses examine combined fly and bottom ash from a modern waste-to-energy facility that meets requirements of the Clean Air Act Amendments for Maximum Achievable Control Technology.

An assessment of the resource availability of biomass and the potential of utilization of renewable energy systems in Detroit Lakes, Minnesota is presented. The feasibility of retrofitting the existing power plant to house a biomass energy system is discussed. Survey and evaluation of current off-the-shelf farm implement equipment which can be adapted to the handling of selected biomass materials is presented. Density studies on sunflower stalks, grain straw, and forest residues are included. (DC)