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.

We will employ the formula of Dulong -

 h = 14,500 C + 62,000 (H - O/8) 

to compute the theoretical heating powers of these fuels. In the case of methane, CH, the formula is not true, but the error is not great enough to seriously affect the result. This gives for the combustion of one pound of:

 Anthracite 14,500 Br. Heat Units.

Bituminous 14,200 " " "

Petroleum 20,300 " " "

Coal gas 20,200 " " "

Generator gas 3,100 " " "

Water gas 8,500 " " " 

Reducing the above to terms of pounds of water evaporated from 212° F., we have:

POUNDS OF WATER EVAPORATED FROM 212° F.

 Anthracite 15.023

Bituminous 14.69

Petroleum 21.00

Coal gas 20.87

Generator gas 3.21

Water gas 8.7 

The results of experiments show the efficiency of fluid-burning furnaces to be about ninety per cent., while with coal sixty per cent. may be taken as a good figure. The great difference in the efficiencies is due to the fact that fluid fuels require for combustion very little air above the theoretical quantity, while with the solid fuels fully twice the theoretical quantity must be admitted to dilute the products of combustion.

Correcting our previous results for these efficiencies, we have:

POUNDS OF WATER ACTUALLY EVAPORATED FROM 212° F., PER POUND OF FUEL.

 Anthracite 9.0

Bituminous 8.8

Petroleum 18.9

Coal gas 18.8

Generator gas 2.9

Water gas 7.8 

These figures agree closely with the results of experiments.

We will now consider the subject of cost.

The following cities have been selected, as manufacturing centers, termini of railroads, or fueling ports for steamers.

In the case of petroleum, as it is rarely shipped in the crude state, an approximation is made by adding to the cost at the nearest shipping port the freight charged on refined petroleum, and ten per cent. to cover duties and other charges.

Owing to the difficulty of obtaining prices, in some of the cities, there may be some errors.

 COSTS. MARCH, 1884. 
 Anthracite Bituminous Coal gas

per ton of per ton of per 1,000

2,240 lb. 2,240 lb. cubic feet. 
 New York $4 00 $4 25 $1 75

Chicago 5 00 3 50 1 25

New Orleans 6 00 3 50 3 00

San Francisco 12 00 7 50 3 00

London 5 00 3 00 0 75

Port Natal 12 50 11 00

Sydney 12 00 7 00

Valpariso 11 50 7 50 
 Generator Crude Water gas

gas per 1,000 Petroleum per per 1,000

cubic feet. bbl. of 42 gal. cubic feet. 
 New York $0 45 $1 80 $0 50

Chicago 45 2 00 50

New Orleans 45 2 50 60

San Francisco 55 2 00 60

London 43 2 70 45

Port Natal Ap- 4 00 Ap-

Sydney proxi- 4 50 proxi-

Valparaiso mation. 3 00 mation. 

In calculating the following table the specific gravity of coal gas is taken at 0.4; generator gas at 0.44; water gas at 0.48; petroleum, 0.8.

 POUNDS OF FUEL FOR $1.00. MARCH, 1884. 
 Anthracite. Bituminous. Petroleum. Coal Water Generator

gas gas. gas. 
 New York 560 527 156 18 74 76

Chicago 448 640 142 24 74 76

New Orleans 374 640 114 10 74 76

San Francisco 187 299 142 10 62 62

London 448 747 104 40 82 79

Port Natal 179 204 71 Ap- Ap-

Sydney 187 320 63 proxi- proxi-

Valparaiso 195 299 94 mate. mate. 

These figures, multiplied by the actual evaporative powers as calculated, give:

 POUNDS OF WATER EVAPORATED FROM 212° F. FOR $1. 
 Anthracite. Bituminous. Petroleum. Coal Generator Water

gas gas. gas. 
 New York 5040 4643 2948 338 220 577

Chicago 4032 5638 2684 451 220 577

New Orleans 3366 5638 2155 188 220 577

San Francisco 1683 2634 2684 188 179 484

London 4032 6581 1966 751 228 640

Port Natal 1611 1797 1342 Ap- Ap-

Sydney 1683 2819 1191 proxi- proxi-

Valparaiso 1755 2634 1776 mate. mate. 
 RELATIVE COSTS. 
 Anthracite. Bituminous. Petroleum. Coal Generator Water

gas gas. gas. 
 New York $1 00 $1 08 $1 71 $14 92 $22 90 $8 70

Chicago 1 00 71 1 50 8 72 18 30 7 00

New Orleans 1 00 59 1 56 17 90 15 30 5 80

San Francisco 1 00 64 1 50 8 75 9 40 3 50

London 1 00 61 2 05 7 16 17 70 6 30

Port Natal 1 00 90 1 21

Sydney 1 00 34 1 39

Valparaiso 1 00 44 1 03 

These figures are very much against the fluid fuels, but there may be circumstances in which the benefits to be derived from their use will exceed the additional cost. It is difficult to make a comparison without considering particular cases, but for intermittent heating petroleum would probably be more economical, though for a steady fire coal holds its own.

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