The speaker, R. Thomas Willson, senior vice president of the American Iron and Steel Institute, noted that the Environmental Protection Agency has estimated there is over $1-billion worth of recoverable metals alone "waiting to be mined" annually from the nation's garbage.

"There's also more than $1-billion worth of energy waiting to be released from that trash," he continued. "The energy value of the refuse generated every year in the United States is equivalent to 290 million barrels of low sulphur fuel oil or 800,000 barrels a day-equivalent to 5 per cent of the current domestic oil consumption, or about two-thirds of our former imports from Arab countries."

Mr. Wilson added, "The total municipal refuse collection, if converted into energy at normal efficiency, could generate 14,000 megawatts of electricity-fully 6 per cent of America's total annual electric production."

These cold figures, coupled with the energy crisis, have attracted a host of blue-chip corporations into the waste-energy conversion field. They are competing with companies that have specialized for some time in the business of reducing municipal and industrial waste to burnable, power-producing fuels.

The big names include the Monsanto Corporation, Garrett Systems, the American Can Company, the Continental Can Company, the Raytheon Company, the Allis-Chalmers Corporation and Combustion Engineering, Inc.

Combustion Equipment Associates, Inc., whose record sales of $60.2million for the nine months ended Dec. 31, 1973, seem small by comparison with such giants, was apparently first to operate a new type of municipal waste-energy conversion plant at Brockton-East Bridgewater, Mass. It opened last October.

Wheelabrator-Frye, Inc., with 1973 sales of $257.3-million, is the United States licensee of Von Roll, a Swiss engineering company. Wheelabrator-Frye is now building at Saugus, Mass., the world's largest waste plant, which will convert 1,500 tons of refuse a day into steam to be used by the General Electric Company's Lynn works.

This plant, costing about $30-million, will handle the waste of 18 adjacent communities to provide G.E. with the equivalent of about 1,750 barrels of low-sulphur fuel oil a day.

Like similar projects, it will also recover ferrous and other metals for use as scrap, as well as an ash that can be used for roadfill or sanitary landfill.

The Von Roll system is the most widely used in the world with 88 systems in operation, many for more than 10 years. More than 50 others are now under construction.

John W. Clark, director of government relations for WheelabratorFrye, said that Frankfurt, West Germany, now produces 7 per cent of its electrical energy and Amsterdam the Netherlands, 6 per cent, from Von Roll systems.

Last March, when American Can announced the formation of Americology, a unit for recycling solid waste, H. Blair Smith, vice president of environmental affairs stated:

"Simple open-pit dumping and burning of garbage-methods developed by the armies of Julius Caesar-can no longer be tolerated on either environmental or economic grounds."

Americology, along with others, is now in negotiations for complete systems in Dade County (Miami), Fla.; Milwaukee, and Bridgeport, Conn.

Other major projects are planned for Boston; Cleveland; the New Jersey meadowlands; Dade City, Fla.; Orange County, Calif., New Orleans; Essex County, N.J.; Ft. Lauderdale, Fla., and Hempstead and North Hempstead, L.I.

"The reasons behind all this activity are simple," Robert M. Beningson, president of Combustion Equipment, said in a recent interview. "The Public Service Electric and Gas Company in New Jersey has been reportedly paying an average of $25 a ton for coal recently against $16 a ton in October. That's equal to $1 to $1.10 per million B.T.U.'s heat."

"In 1971, utilities were paying 40 cents per million B.T.U.'s for coal," Mr. Beningson declared. "This reached 55 to 65 cents in 1973 and is now generally at $1 or more, depending on the source of the coal.

"In 1971 our Ecofuel, the dry material left after processing, was worth only about 10 cents and was really only marginal as a fuel. Two years later it was worth 30 cents, but today in the Northeast it produces a fuel worth $1 per million B.T.U.'s. That's like $6-$8 a ton garbage against only $2 in 1973, so it's well worthwhile."

Mr. Beningson said that his recovered fuel had a 7,000-8,000 B.T.U. per pound value and a lower sulphur content than any other fuel but natural gas.

"In such times, we're obviously competitive," he said.

Continental Can credits the wave of environmentalism with making the public aware of the potential for waste conversion.

Continental's proposal is to design, construct and operate solidwaste processing facilities on contract. It would charge a per-ton fee. Connecticut last fall became the first to adopt a statewide plan for construction of recycling plants-one starting up each year between 1975 and 1985.

The first, to be situated in Bridgeport, would be patterned after a municipal system in St. Louis, where the Union Electric Company burns about 300 tons of garbage a day as a supplemementary source for power generation.

By 1985, Connecticut expects to be recycling about 60 per cent of its household and industrial waste, 12 times today's percentage. This would provide about 11 per cent of its electrical needs, along with enough reclaimed steel for 200,000 automobiles.

Massachusetts announced plans last month for a $342-million network of refuse recycling plants that would turn about 56 per cent of the state's waste into combustible fuel. This would meet about 15 per cent of the total energy used by the state's utilities to produce electricity.

4. Horner & Shifrin, "Solid Waste as Fuel for Power Plants," (1973), pp. iii-v:

SUMMARY

The study summarized in this report was directed toward the determination of the technical and economic feasibility of burning prepared municipal refuse as supplementary fuel in large suspensionfired utility boilers. The study was conceived under the premise that

if municipal refuse were properly prepared, and if the percentage of refuse to pulverized coal were kept to a practical minimum, potential operating problems in large boiler installations would be little, if any, different than if only coal were fired.

The study included consideration of the physical and chemical characteristics of raw refuse, and of refuse with certain of its components removed. Consideration also was given to the characteristics of the ash and residue resulting from the combustion of refuse, and to the potential effects upon operation and maintenance of the components of boiler units.

Adaptation of commercially available mechanical equipment for the processing and handling of raw and prepared refuse was studied. The studies included consideration of the modifications required for application of the process for those types of boilers in common use.

An assessment was made of the capability of major utility boiler installations to consume sufficient refuse as supplementary fuel to serve as a significant method of refuse disposal for metropolitan areas. The relative economics of the full-scale application of the process also was assessed.

An evaluation was made of the effects of the process upon public health and air pollution control. Consideration was given to the social and economic relationships between utilities and public agencies having bearing upon the application of the process.

For convenience of assessment of specific details of equipment and circumstances, the study is referenced to the St. Louis, Missouri metropolitan area. It is considered that this area may be regarded as being reasonably typical of the metropolitan areas of the most heavily developed portions of the United States.

Consideration was given to the type and the scale of facilities required to effectively test the processing, transporting, and firing of refuse to a boiler, and to properly evaluate the effects of firing refuse as a supplementary fuel upon the operation of a boiler.

CONCLUSIONS

The principal conclusions resulting from the study summarized herein are as follows:

1. The process is physically and technically feasible, under the premises that refuse would be milled to effect a particle size of about one inch, and that the milled refuse would replace approximately 10 per cent of the heat value of the pulverized coal consumed in suspension-fired boiler furnaces.

2. Potential operating problems accruing from firing milled refuse as supplementary fuel to large boiler furnaces probably are minimal. Actual adverse effects, if any, can be assesed completely only by full-scale testing of a typical boiler unit over a reasonable period of time.

3. The process can be applied by adaptation of existing technology and commercially available mechanical equipment, with the probability that essentially no further developmental effort would be required. Modifications to existing suspension-fired boilers normally would be minor.

4. Considering that the milled refuse has a value as fuel to large utility boilers on the order of $2.50 to $4.00 per ton, the

net cost of the disposal of refuse by the process should be highly attractive in many of the metropolitan areas of the United States.

5. The capability of suspension-fired boilers to consume the prepared refuse as supplementary fuel is great enough to permit the process to serve as a principal method of refuse disposal for many metropolitan areas, even when the supplementary fuel is fired as only 10 per cent of the total fuel. By 1973, the suspensionfired boilers in the St. Louis area will have the potential capability of consuming over twice the amount of refuse produced in the entire metropolitan area.

6. Ambient air quality in many metropolitan areas could be improved by application of the process.

RECOMMENDATIONS

Although the probabilities of adverse effects upon the components of large utility boilers by application of the process appear to be minimal, one area of uncertainty relates to the long-range effects upon boiler operation, such as in corrosion and bottom-ash handling. The Union Electric Company of St. Louis, Missouri, which has cooperated fully in this study, has indicated it would consider a specific proposal for the use of one of its major boiler units as a prototype. Since the testing of a large boiler unit on less than a full-scale basis is not considered to be sufficient to adequately assess the effects of the process, the following recommendations are made:

1. Arrange for the purchase and installation of equipment to process refuse, to transport the processed material to the boiler unit designated by the Union Electric Company, and to fire the material as supplementary fuel to the boiler unit for a period of approximately two years. The most desirable installation for this purpose would be one which would permit full assessment of processing operations as well as boiler performance. Since the process has the promise and potential of being significant as a primary means of refuse disposal for a large part of the United States, it is believed appropriate that the financing of a prototype installation be underwritten by the Federal Government.

2. The most critical areas of investigation are believed to relate to boiler operation and performance. Should the financing of fullscale processing operations not be practical at this time, it is recommended that facilities be installed to permit full-scale testing of the boiler, even should it be necessary to forego the complete installation and testing of the refuse processing equipment.

5. "Municipal Solid Waste-A Source of Energy," NCRR Bulletin (Summer 1973), pp. 2-4.

There are 4.3 billion tons of solid waste generated in the United States annually from residential, commercial, industrial, mining, institutional, and agricultural sources. Of these sources, roughly three percent is municipal solid waste (MSW). High in organic content and comprised mainly of residential, commercial, and some industrial wastes, MSW can be utilized as an economical and ecological fuel in urban areas where the nation's energy demands are the highest. The

utilization of MSW as a fuel will not only relieve to some extent the much talked about "energy crisis", but more importantly will help in disposing of solid waste through resource recovery.

VALUE AND AVAILABILITY

There are sound ecological reasons for using refuse to create energy: Retrieving energy from MSW provides a useful application for what is now being discarded. This is one concept of resource recovery and is accepted as an important step toward improving the environment;

When refuse is used as a source of energy, conventional fuel of an equivalent BTU value is preserved thus saving some of our natural resources.

The cost of municipal waste disposal can be substantially reduced when the combustible fraction (i.e. paper, plastics, food wastes, wood, yard clippings, etc.), representing some 80 percent of mixed refuse, is utilized in energy recovery systems.

(The other 20 percent inorganics can be processed with materials recovery systems to separate metals and glass.)

In 1970, if all the MSW generated in the U.S. were converted into electricity, 3.65 percent or about 50 billion kilowatts should have been provided. The Bureau of Mines has estimated that if all organic wastes, not just municipal refuse -but also manure, logging, and wood manufacturing residues, agriculture crops and food wastes, industrial wastes, municipal sewage solids and miscellaneous organic wastes were combined and processed into a low grade oil, a process BuMines feels technically feasible, two billion barrels of oil would be yielded annually; or the equivaent of 50 percent of the 1970 U.S. demand for oil, according to one study.

However, the majority of this nation's total waste, of which MSW is only a small portion, is not readily accessible for energy conversion due to its location in rural-agricultural areas quite removed from highly urbanized areas. Energy demands are highest in these urban areas, where 74 percent of the U.S. population lives, and hence where 74 percent of MSW is generated. Upon converting this available urban MSW into energy, 790,000 billion BTU could be recovered, which would replace 35.9 million tons of coal annually. For reasons of line loss, power generating stations are normally located in or around urban areas. This restricts the energy potential of some of the MSW and the bulk of agricultural waste due to high transportation costs of rural-agricultural wastes. An important point here and one that is developed later in this article, is the conversion of waste from the form in which it was discarded to storable-transportable fuel. Clearly raw refuse does not have this characteristic.

Nevertheless, when refuse and fuel demand are in reasonable proximity, the use of refuse for fuel has some desirable characteristics. Of concern in air pollution abatement is the quantity of sulfur contained in power plant fuels. During the generation of power in fossil fuel plants, sulfur oxides are formed as a combustion byproduct which must be controlled to meet existing Federal and state air pollution regulations. This has caused power companies to look toward grades of fuel with less sulfur content. Although MSW is