Equipment and Design

Page 1 ... discussions of equipment and plant design since the progress normally made in eight ... Recently the Blaw-Knox Company designed and built a...
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will evolve new processes which can be constructed from the stocks of surplus equipment and thus convert both to useful productive plants. Recently the Blaw-Knox Company designed and built a plant, installed in a new building 70 feet high, which make! possib!e the mixing of carbon black (a product of natural gas) with liquid rubber. The milling time needed to make a certain grade of rubber is thereby cut by one third. A simple flow diagram of the process is shown in Figure 1. The carbon black is delivered by railroad cars on the left, taken by the air-activated conveyor into the storage room, and sent as needed to the hopper. The arrows show the course of the carbon black as it is pum ed into the main synthetic rubber lant for rmxtuw with latex Before the rubber coagulates into pkstic form. Previously the mixing was done after the rubber had coagulated. Blaw-Knox engineers received the basic information on how the scientists had been able in the laboratory to mix carbon black with liquid latex successfully and began work on blueprint layouts and building. The blueprinting was completed by July 1, and on August 16 the first rubber was turned out, properly processed. The flow diagram indicates that this project could have been assembled promptly from surplus equipment, since much of it is typical .of that used in unit operations of chemical engineering-the air conveying system, pumps, scales, and tankage. The highly important result of shortening the compounding time for rt special rubber came from fundamental research and good engineering. These two tools of the chemical industry can accomplish the same wonders in adapting surplus material to postwar needs.

an excellent time to been presentation of discussions of equipment and plant design since the progress normally made in eight or ten years has been concentrated into the last four by the necessity of defense and war programs. Shortly much of this new knowledge may be available for wider and more humane uses. This opportunity is unique in the fastmoving history of the chemical industry. Equally true it is that the end of the war will make available much idle equipment for industrial use. Some of this equipment can be used in the way for which it was designed. A far larger portion, however, must be modified, knocked down, and reconstructed for special purposes. No one knows how much equipment w111 be thrown on the market by government agencies, but it is certain to be enormous, measured by any prevlous standard. The list will include entire plants some of which will have a fair value exceeding a hundred million dollars, while millions of dollars represent equipment and apparatus valued from a few cents to several hundred thousand dollars for individual pieces. There is a considerable economic problem attached to this huge surplus storehouse. To assist in a better knowledge of this equipment, with satisfaction to both seller and buyer, will be but one of the many objects of this colurpn. There seems to be a good possibility that the wonderful work of the scientific research groups ~ O V E M B E R ,1944, is

‘ 7 1 4 r - l C OWST UECTORW

Figure 1 Carbon BlackLatex System

One of the most useful innovations in the technical field during the past three years has been the fuller development of “unitsas complete, ready-to-operate plants. The generic principle is sometimes referred to as packaged units. The extent to which this policy has been developed is remarkable. In the chemical eauitment field the Dackamd unit idea often consists i n placing or properiy instzlling motors, instruments, regulating controls, and secondary foundations on a

a laborless heating device and to hold coal sales in competition with automatic oil burners, the Iron Fireman has “grown up”. It is now a completely packaged unit serving the light industrial field. One +equent ap lication is in connection with HR?! boilers of 1500 and 2000 square feet of heating surface. Boilers of this capacity and type have long been the old reliable work horses of small manufacturing plants throughout the country but have not been known, especialb, for efficiency under handfiring conditions. The moderniaed firing methods with such devicas as the Iron Fireman coal-flow underfeed stoker (shown diagrammatically in Figure 2) change many (Continued on page 68)

KRT Barn 148sa FT. HTG. SURF.

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old boiler room canditions vastly for the better. While carrying a slightly higher load, the steam pressure is maintained more nearly constant with fewer man-hours in the boiler room. Financially imporbant is a saving of 22.5% in coal consumption. It is a safe guess that one of the most interesting developments to come out of the thousands of new designs utilized in war activities will be the fuller use of the wonderful properties of new alloys and materials. While the tensile strength of certain alloy steels has been steadily increased to over 200,000 pounds per square inch, ordinary machining and tool operations also have become more precise; heavier safe loads are thus ermissible on each separate part, One example out of many to iffustrate the results that this combination of improvements will yield is the Hycon oil pump, patented and manufactured by the New York Air Brake Company. The size and weight of this small precision alloy pump may be judged from the two half-inch pipe o enings in the top of the casin but its normal capacity is 6 galpons per minute of oil against a t e a d of 3OOO pounds per square inch (6950-foot head) a t 4500 r.p.m. It is hoped that one of the results from these articles will be to increase the use of old devices in new ap lications. There are great rewards within reach of those who wilyextend a successful, proved device into a new duty and thereby make some piece of equipment more useful. Consider the water-sealed gas holder. These storage tanks of two or three lifts can be raised and lowered to change their volume from zero to full capacity. A series of two or three inverted steel bells dip into water and permit the bells to move up or down while sealed to the atmosphere. This old device ap hed to the t o of tanks for the storage of light volatile liquig has recently k e n imyyoved by Graver Tank & Manufacturing Company. The new expansion roof" built into the top of any tank o rates the same as the single lifts or bells of the gas holder. tank roof is bmlt as a self-supporting, shallow inverted bell, the skirt of which moves in a concentric layer 01 water constructed a t the top of the tank. During the temperature change in the vapor over the liquid stored in the tank due to a noon sun, the roof simply raises until the increased volume of the vapor at the higher temperature has been rovided. At night as a result of lower temperature, the vapor vofume contraction is replaced, not by creating a vacuum or drawing in air, but simply by the fall of the roof until normal vapor pressure exists. Valuable vapors of the materials stored in the tank are not lost with riaing temperatures or diluted with air by falling temperature. The proportion of the tank proper, usually added for the gasholder adaptation roof, for gasoline storage tanks is:

%

Barrels Stored 5000 80,000

Roof Expansion Capacity, Cu. Ft. 3,618 54,225

The saving in gasoline due to this type of expansion roof, valued a t 7 cents per gallon, will exceed s1x thousand dollars per year. Charles Owen Brown is a consulting chemical engineer identified with the nitragen fixdtion industry for over a quarter of a century. Actlve in this field as Lieutenant Colonel of Ordnance durin the last war, he has since been connected with the chemical indusby, here and in Europe. His present oflice was established in 1937, specializing in high-pressure technique, synthetic ammonia, nitric acid, alkali, alcohols, and aldehydes. His experiences are closely related to many types of equipment and plant layout. O n e of the large synthetic ammonia planb of the present defense program was designed and put into operation under his supervision. Brown has lectured in chemical engineering economics at Brooklyn Polytechnic Institute) he i s a member of the State of N e w York Industrfal Commission and of War'Produotion Board, and is a consultant to the Army Engineer Corps.