RELATIVE COSTS OF FLUID AND SOLID FUELS.

[Footnote:  Read June 20, 1885.]

By James Beatty, Jr., Member of the Club.

During the past twenty-five years there have been numerous efforts to introduce fluid fuels as substitutes for coal, for the evaporation of water in boilers, metallurgical operations, and, on a small scale, for domestic purposes.

The advantages claimed for these fuels are:  Reduction in the number of stokers, one man being able to do the work of four using solid fuel.  Reduction in weight, amounting to one-half with the better classes.  Reduction in bulk; for petroleum amounting to about thirty-six per cent., and with the gases, depending on the amount of compression.  Ease of kindling and extinguishing fires, and of regulation of temperature.  Almost perfect combustion and cleanliness.

Siemens used gas, distilled from coal and burnt in his well known regenerative furnace.

Deville experimented with petroleum on two locomotives running on the Paris and Strassburg Railroad.

Selwyn experimented with creosote in a small steam yacht, and under the boilers of steamship Oberlin.

Holland experimented with water-gas in the furnace of a locomotive running on the Long Island Railroad.

Isherwood experimented with petroleum under the boilers of United States steamers.

Three railroads in Russia are using naphtha in their locomotives, and steamers on the Volga are using the same fuel.

Wurtz experimented with crude petroleum in a reheating furnace at Jersey City.

Dowson, Strong, Lowe, and others have devised systems for the production of water gas.

These experiments, in general, have produced excellent results when considered merely in the light of heat production, but, in advocating their systems, the inventors seem to have overlooked the all-important item of cost.

It is the object of this paper to show the impracticability of such systems when considered from a commercial standpoint, so long as the supply of coal lasts, and prices keep within reasonable limits.

In many cases, authors on the subject have given purely theoretical results, without allowing for losses in the furnace.

The fuels to be considered are anthracite and bituminous coals, crude petroleum, and coal, generator and water gases.

The average compositions of these fuels (considering only the heating agents), as deduced from the analysis of eminent chemists, are: 

Percentage by weight.

_______________________________________________________

_
|  C |  H  | O | Co |CH_{4}|C_{2}H_{4}
+----+-----+---+----+------+----------
Anthracite        |87.7| 3.3 |3.2|    |      |
Bituminous        |80.8| 5.0 |8.2|    |      |
Petroleum         |84.8|13.1 |1.5|    |      |
Coal gas          |    | 6.5 |   |14.3| 52.4 |  14.8
Generator gas     |    | 1.98|   |35.5|  1.46|
Water gas         |    | 6.3 |0.6|87.8|  1.2 |
------------------+----+-----+---+----+------+----------

We will employ the formula of Dulong—­