Cooking Process

Advantages.—The cells of the material are more completely broken down so that a larger amount of grease can be more readily recovered; all material is enclosed during the process so that the gases are more readily deodorized with less volume to be deodorized; in the modern plants the mechanical condition of the by-products is better.

Disadvantages.—Increased fixed cost of building and equipment; increased operating cost; increased maintenance cost.

Osborn believes that by-products produced by either method have the same relative market value. In plants that have been operated by both methods, the experience has been that the additional amount of grease recovered by the cooking method has more than offset the increased costs and at the same time the odors were eliminated to a larger extent.

In establishing a reduction plant, Rudolph Herring says that the great fear is creating a nuisance. He further asserts that, owing to unpleasant odors apt to arise at the works, it is necessary to have good ventilation and also a subsequent treatment of some of the vapors and liquids which result from the process. These contingencies make it advisable, he thinks, to locate the plant in a neighborhood where the possibility of occasional unpleasant odors will not materially injure value of adjoining property.

The Chicago Waste Commission gives this suggestion as a solution of the odor problem: “In addition to the steam and electrical power that can be furnished from a destructor plant to operate a reduction plant, the exhausting of all gases carrying odors from the reduction works and passing them through the destructor would prove one of the greatest advantages from a sanitary and economical standpoint to be derived from a combined method of disposal of all municipal wastes.”

Osborn says: “Economical results may be obtained by utilization of heat in the disposal of garbage mixed with other refuse, by burning, but to prove satisfactory the maximum sanitary results must be obtained at a minimum cost, and when the quantity is such that it will warrant utilization the reduction method will continue to show more economical results, and with proper attention given to details and sanitary features the work can be conducted without nuisance.”

Reduction is a method which can be adopted only by large cities. It seems to be usually agreed that cities with less than 100,000 population and producing less than 75 tons of garbage daily will find the reduction process will not pay as a business venture. One writer says in no place of less than 150,000 population can these kind of plants be operated successfully. Venable places the minimum population at 100,000. He says that as approximately 80 per cent. to 90 per cent. of kitchen garbage is water and only 10 per cent. to 20 per cent. is composed of grease and other substances it takes a large amount of garbage to make reduction plants profitable.

The cost of a reduction plant will range from $1,500 to $3,000 per ton daily capacity, according to published reports.

The gross cost of garbage destruction by the reduction method varies from $1.50 to $2.50 per ton of raw garbage. In only a few instances does the sale of the by-products meet or exceed expenses. In a majority of cases, the process is carried on by private companies, the most being subsidized by cities to amounts varying from 50 cents to $2.50 per ton. A few companies pay the city for all garbage delivered to the plant.

The by-products of the reduction method are grease and tankage. It is generally agreed that ordinary garbage contains from 2 per cent. to 3 per cent. by weight of grease and must yield from 200 to 400 pounds of tankage per ton.

Columbus, Ohio, has been conducting experiments in making alcohol from green garbage and its reports indicate that cities having reduction plants may produce another by-product from their waste. The experiments were carried on for some time under the direction of the assistant superintendent in cooperation with Dr. James J. Morgan, a Chicago chemist who has patented a process of distilling the alcohol from chemically-treated garbage. It requires only a slight addition to the present processes of the plant. The garbage is treated with a two per cent. solution of sulphuric acid for cooking, then with lime and finally with yeast for fermentation. The claim is made that the amount of grease and tankage is not reduced by the process, and it is estimated that every ton of garbage will yield about six gallons of alcohol. The superintendent of the Division of Garbage and Refuse Disposal in November, 1917, informed the New York State Bureau of Municipal Information that the final report on the experiment “was favorable to the process, but our city council did not see fit to authorize the installation of the necessary equipment for the process.”

J. W. Turrentine says that on a basis of figures obtained in the operation of a number of reduction plants, it is shown that the average cost of reduction is $2.41 per ton, and the gross receipts $3.30 per ton, giving a profit of 89 cents per ton raw garbage. He asserts that when consideration of cost of collection is excluded, the rendering of garbage is distinctly more profitable than incineration.

Cleveland and Columbus have been the cities most successful in operating municipal reduction plants. In one year the Columbus plant received 21,628.97 tons of garbage, or 211 pounds of garbage per capita. From this and the 183 large dead animals received, the actual production was as follows: Grease, 1,186,985 pounds; tankage, 1,753 tons; hides, 183. The value of these by-products were: Grease, $57,672.21; tankage, $12,987.84; hides, $1,062.30, or a total of $66,772.35.

Each ton of garbage produced 54.87 pounds of grease and 162.1 pounds of tankage. The grease value per ton of garbage was $2,435; the tankage, 60 cents, and the hides 5 cents, or a total of $3,085 per ton of garbage. The actual cost of operation was $40,220.78 or $1,859 per ton. The net profits were $26,502.57 or $1.226 per ton of garbage.

Cleveland in one year produced 2,940,000 pounds of grease and 10,016,000 pounds of tankage, the city receiving for them $151,162.48. This reduction cost per ton of green garbage was $1.97½ and the earnings per ton of green garbage was $3.47, making the net earnings per ton of garbage $1.49½.

New York City is selling its garbage to a private company. It made a contract for 1914 to 1916, inclusive, and the right to renew the contract for two more years on the same terms and conditions. The city receives at the rate of $62,500 for the first, $87,500 for the second, and $112,500 for the third and each of the succeeding two years. Plans are now being made to operate a municipal plant.

Table VII
METHODS AND COST OF DISPOSING OF GARBAGE
Name	Method of Disposal	By Whom Done	City Own Dump? If Not, Annual Rental	City Own Farm and Hogs?	Is farm Rented by City?	Kind of Plant	Capacity	When Built	Design	Any Odor?	Annual Cost of Operation	By- Products	What is Done with By-Products	Annual Revenue from By-Products	Net Cost of Disposal 53		Net Profit
Name	Method of Disposal	By Whom Done	City Own Dump? If Not, Annual Rental	City Own Farm and Hogs?	Is farm Rented by City?	Kind of Plant	Capacity	When Built	Design	Any Odor?	Annual Cost of Operation	By- Products	What is Done with By-Products	Annual Revenue from By-Products	Per Ton	Year	Net Profit
New York City 54	Reduction.	Contract. Building municipal plant.				Reduction.	2,000 tons.	1896	Arnold.			Grease and tankage.					$112,500 a yr.
Buffalo	Dumping and Incineration.	Contract.	Some of them.			Incineration.	40 tons.	1903	Heenan-Froude.						$1.25
Rochester	Reduction.	Contract. City has decided to own its plant.				Reduction.		1907	Genesee Reduction Co.			Grease and tankage.
Albany	Fed to pigs.	Contract.		No.	No.
Binghamton	Feeding and burning.	Private sanitary companies.		No.	No.
Schenectady	Reduction.	City.				Reduction.	30 tons.	1914	Chamberlain.	Yes.	$27,000.00	Tankage and grease.	Sold.	$3,000.00	10.23	$34,200.00
Syracuse	Reduction.	Contract, planning municipal operation.								At times.
Troy	Dumping.	Contract.	$12,000
Yonkers	Incineration.	City.				Incineration.	9 tons.	1839	N. Y. Garbage Crematory.	No.	3,380.50				1.40	3,880.50
Utica	Reduction.	Contract.				Reduction.				Very little.		Grease.	Sold for soap, residue used for fuel.			4,100.00
New Rochelle	Incineration.							1917	Morse-Boulger.
Watertown	Feeding to pigs.			No.	No.
Auburn	Dumping and ploughing under.
Beacon	Dumping for fill.		No. No rental.
Mechanicville	Dumping for fill.	Contract.	No. No rental.
Dunkirk	Feeding and ploughing under.		No.	No.	No.
Saratoga	Dumping.		$50 per yr.
Middletown	Dumping for fill.		No.
Kingston	Dumping.		No.
Jamestown	Ploughing under.	Contract.	No.
Fulton	Dumping for fill.		Yes.													600.00
Port Jervis	Dumping.	Contract.	No.													960.00 55
Elmira	Incineration and dumping.	Dumping only by city.	No. $300.			Incineration.	Uses about half city garbage.	1906		No.		None.
Salamanca	Dumping.	City.
Rome	Dumping.
Niagara Falls	Dumping in river.
Cortland	Dumping.	Contract.	No.													200.00 56
Cohoes	Dumping.		Owned by contractor.
Plattsburgh	Dumping on land and in water.		One dump.
Ithaca	Dumping for fill.	City.	Some. No rental.
Olean	Feeding to hogs.			No.	No.
Johnstown	Dumping.		No. $100 per year.
Ogdensburg	Dumping.
Gloversville	Dumping.	Contract.	Yes.
Hudson	Feeding to hogs.	Contract.	No.	No.	No.
Little Falls	Feeding to hogs.	Contract.		No.	No.
North Tonawanda	Ploughed under.	Contract.	No. No rental.
Newburgh	Feeding and ploughing under.	Contract.		No.	No.
Norwich	Dumping.		No. $50.
Mount Vernon	Feeding and dumping for fill.	Contract.	Contractor rents it.	No.	No.
Lockport	Feeding and dumping.	City.	Yes.	No.	No.
Hornell	Feeding and ploughing under.	City.	No. $50.	No.	No.
Rensselaer	Feeding and dumping.	City.	Yes.	No.	No.
Batavia	Dumping and feeding.	City.	Yes.	No.	No.
Tonawanda	Feeding and dumping.	Contract.	No.	No.	No.
Corning	Feeding to hogs.	Contract.	Contractor owns farm.	No.	No.
Oswego	Dumping on land.
Canandaigua	Feeding to hogs.	Private company.		No.	No.
Borough of Queens	Crematories, dumping and reduction.	Crematories and dumps by city. Reduction by contract.	No.			3 crematories.	30 tons.57	1900			.161 cu. yd.58
Amsterdam	Incineration.	City.
Poughkeepsie	Dumping.	City.	No.
Atlanta, Ga.	Incineration.	Contract.				Incineration.	250 tons.	1913	Destructor Co.	None from operation.	25¢ per ton	Cinders.	Dumped.	None.	59	59	59
Columbus, Ohio	Reduction.	City.				Reduction.	200 tons.	1910		Slight.	$1.86	Grease, tankage, hides.	Sold.	$66,772.35			$1.226 per ton
Cincinnati, O.	Reduction.	Contract.				Reduction.			Heenan-Froude.	Not 50 feet outside wall	$68,892.45	Electric power.	Operates pumping station.	$10,000.00	$1.26 60
Milwaukee, Wis.	Incineration.	City.				Incineration.	300 tons.	1910
Detroit, Mich.	Reduction.	Contract.				Reduction.			Detroit Reduction Co.						City pays nothing.
Washington, D. C.	Reduction.	Contract.				Reduction.		1900	Arnold.	40 miles from city.		Grease and tankage.	Sold.		$2.31 61		$1.89 per ton 62
St. Louis, Mo.	Reduction.	Contract.				Reduction.	400 tons.	1913		Occasionally		Grease and tankage.	Sold.		.87 63
Lawrence, Mass.	Feeding to pigs.			Two loads daily sent to Poor Farm. Rest sold.													$1.25 a load.
New Orleans, La.	Dumping for fill.	City.	Yes.
Hartford, Conn.	Feeding to pigs and burned.	City.	Yes.	No.
Baltimore, Md.	Reduction.	Contract.														68,000.00 64
Bridgeport, Conn	Reduction.	Contract.				Reduction.	60 tons.	1910		Occasionally.					5064
Cleveland, O.	Reduction.	City.				Reduction.	300 tons.	1905	Newburgh Reduction Co.	Very little.	$132,890.00	Grease and tankage.	Sold.	$195,000.00			$1.49½ per ton
Lowell, Mass.	Fed to pigs.																$5,919.77
Cambridge, Mass.	Fed to pigs.																$15,000.00 65
Louisville, Ky.	Dumping.		No.
Pittsburgh, Pa.	Reduction.	Contract.				Reduction.				Yes.					$2.25	$290,000.00
Denver, Col.	Fed to hogs.	Contract.		No.											Free.
Savannah, Ga.	Incineration.	City.				Incineration.	130 tons.	1914	Heenan-Froude.	No.	.61556	Steam and clinker.	Used on roads.		.36
Chicago, Ill.	Reduction and incineration.	City.				Reduction.	900 tons.	1913	Arnold.	Very little.		Dried garbage.	Sold.			$144,744.00
Kansas City, Mo.	Fed to pigs.	Contract.		No.
Boston, Mass.	Reduction.	Contract.				Reduction.										$925,318.56 66
Lynn, Mass.	Fed to pigs.
Grand Rapids, Mich.	Fed to pigs.			No.													45¢ per ton.
Minneapolis, Minn.	Incineration.	City.				Incineration.		1905	Decarie.	No.		Power.	Heats buildings, lights buildings and streets.	$27,000.00	.85	$16,000.00
St. Paul, Minn.	Fed to hogs.			No.													80¢ per ton.
Jersey City, N. J.	Dumping for fill.	Contract.
Passaic, N. J.	Burial.
Paterson, N. J.	Incineration.	City.				Incineration.	60 tons.	1912	Destruction Co.	No.			None.		.877 67	$9,527.42	$1.18
Trenton, N. J.	Incineration.	City.				Incineration.	65 tons.	1901	Davis.	No.		Only ashes.	None.		.48 69	$7,108.3769
Dayton, O.	Reduction.	City.				Reduction.	125 tons.	1915		Slight.		Grease and tankage.	Sold.
Providence, R. I.	Fed to pigs.		No.
Charleston, S. C.	Dumping.
Nashville, Tenn.	Feeding to hogs.
Seattle, Wash.	Dumping for fill.	City.
Spokane, Wash.	Incineration.	City.				Incineration.	120 tons.	1908	Decarie.	No.		Ashes.	Sold.	$5.00	.60
Oakland, Cal.	Dumping in ocean and incineration.	Contract.				Incineration.	100 tons.	1907	Decarie.						.60
New Bedford, Mass.	Reduction.	Contract.				Reduction.	30 tons.	1905		No.						$25,500.00
Springfield, Mass.	Reduction.	Contract.				Reduction.	75 tons.	1913		Some.					68	68	68
Portland, Ore.	Incineration.	City.				Incineration.	150 tons.	1910	F. P. Smith	No.				3456 per ton.	.3469
Philadelphia, Pa.	Reduction and feeding to pigs.	Contract.				Reduction.	500 tons.			Yes.		Grease and tankage.
Scranton, Pa.	Incineration.	City.				Incineration.	80 tons.		Lewis & Kitchen Co.	No.	.28	Ashes.	Sold.
Reading, Pa.	Incineration.	City.				Incineration.	100 tons.	1914		No.				$1.00 70
Richmond, Va.	Incineration.	City.				Incineration.	100 tons.	1910	Morse, Boulger & Decarie.
Los Angeles, Cal.	Reduction and feeding to pigs.	Contract.				Reduction.	300 tons.	1915		No.		Grease and tankage.					51¢ per ton for reduction, $1 for feeding.
San Francisco, Cal.	Reduction.	Contract.				Reduction.	750 tons.	1897	Chas. Thackery patents.	Much.		None.			.60 71
Newark, N. J.	Reduction.	Contract.
Indianapolis, Ind.	Reduction.	Contract.
Toledo, O.
Worcester, Mass.	Feeding to pigs.	City.		Yes.	No.							Manure and hogs.	Sold.	$38,838.67
New Haven, Conn.	Feeding to pigs and composting.			Yes.
Birmingham, Ala.	Dumping on land.	City.
Memphis, Tenn.	Incineration and dumps.	City.	Yes.			Incineration.	50 tons.			Yes, at times.	30¢ to 40¢
Omaha, Neb.	Feeding to pigs.			No.
Fall River, Mass.	Feeding to pigs.	Contract.		No.											No expense.

Glens Falls and Oneonta, N. Y., report that they have no systems.

Notes

53. A Includes interest, depreciation, maintenance and repair charges.

54. Manhattan, Bronx and Brooklyn Boroughs only.

55. Collection and disposal.

56. No cost for superintendence, man receiving salable rubbish for his pay.

57. Eight-hour capacity.

58. Includes maintenance and repair charges, and is for crematories only.

59. Plant not yet under control of city, court action pending.

60. Labor and supply.

61. Gross.

62. Estimated.

63. Contract price.

64. Price paid by city.

65. City sells for 70¢ per cord ft.

66. Includes collection.

67. Labor only.

68. City may buy plant at end of ten years for $50,000, at end of twenty years it becomes property of city free of cost.

69. Does not include interest and depreciation.

70. Fuel and wages.

71. Price paid reduction company by scavengers.

⁷². Guaranteed.

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