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World Wide Chemistry
O I R Stafford Cripps ^ lias said tha,t the 1948 output target o f 14 mil lion tons of st*?el would be much below demand, including exports of at least 1 million tons to assist in the rehabilitation of western Eur ope. That target is the irreducible mini mum for our recovery plan. Capacity of t he industry t o finish steel is greater t h a n that for crude. Acceptance by the steel workers of continuous shift working was an essential factor in lifting out put during the last quarter of 1947. Urgency o f present needs must not obscure vital importance of long-term expansion on which industry is now engaged. It is abundantly clear that long term target figure at present envis aged is not too high. Steel Companies Chemical Interest The United Steel Cos., Ltd., reports that its gross income for year ended June 30, 1947, was nearly £40 million of which £20.7 million was expended on raw mate rial, fuel, and services and £11.5 million on wages, salaries, and employees' insurance, interests in the chemical field axe extend ing. The company is one of t h e largest earbonizers of coal in the U.K., producing coal gas, tar, and resulting chemicals, through its subsidiary, United Coke & C 'hemicals Co., Ltd. But coal supplies are the basic factor, and output per man-year is not what it should be. Most of the company's own coal mining properties have been transferred told as such or further ash a day to produce 30 tons of caustic processed to make dense soda ash. The soda daily, mostly as 5 0 % solution, al use of hearth-type furnaces for this latter though some solid caustic may be sold. purpose is something of an innovation. This o u t p u t is in addition to the 22 me trier Some soda ash is converted to canst icsoda. tons of sodium bicarbonate being produced Various changes may be introduced. daily in the pilot plant adjacent to the new It is proposed to obtain brine principally factory. The pilot plant probably will from wells in the future. I t is also planned continue in production as long as the to operate the carbonating towers b y pairs shortage o f alkali continues to be acute. in series a t higher pressures in hope of in Essentially, the process consists of creasing the proportion of carbon dioxide treating alkali brines with carbon di absorbed. In such an event less lime oxide, so that sodium bicarbonate is pre will be avilable for the caustic plant. cipitated. The bicarbonate is then heated, Initial output, in the form of sodium bi transforming it to sodium carbonate. T h i s carbonate, will be sold mostly t o glass is mixed with water and quicklime to pro makers. I t is planned to recover common duce sodium hydroxide. salt, provided market arrangements can A natural brine is obtained by washing be made. Waste liquors would be a po the topsoil in the basin of what was tential source of potassium chloride and formerly Lake Toxcoco, an alkaline lake sodium borate Although calcium carbo that has been drained. Brine m a y also be nate will be run to waste for the time being, obtained from wells about 65 feet deep. a dye plant m a y be built nearby to T h e weak brine is concentrated in a solar use it for neutralization of spent acids. evaporator, which is a roughly circular The soda ash and caustic soda produced basin surrounded by a low embankment are expected to be up to U. S. standards. with another embankment spiraling in The caustic soda may contain enough sili toward t h e center. The weak brine is cates to make it unsuitable for rayon man pumped i n at the outer edge of the basin ufacture, however. Maximum selling and passes slowly along the spiral channel prices are fixed at approximately the toward t h e center. The basin covers about price in the U. S. plus freight, shipping three square miles. Normal depth is 3 2 costs, and duties to Mexico City. Dense to 39 inches. Average evaporation is soda ash was priced at a maximum of U. S. about 70 million lb. of water a day. T h e $0.035 a l b . and soda ash at U. S. $0.023 salts contained in the evaporator are suf t o $0.028 a lb. ficient t o supply the alkali plant for four Brine supplies, which cost the company years. There is a theoretical maximum almost nothing aside from royalties, are yield of 8.05 grams per liter of sodium car estimated to be adequate for more than bonate. Brines obtained by washing sur 500 years at present production capacity. face soil are usually more dilute. Fresh water is also cheap and abundant, flowing from artesian wells at t h e plant A brine that has a concentration of salt site. Limestone is obtained from quarries of about 220 grams per liter containing less than 50 miles away, and coke comes about 100 grams per liter of sodium car from northern Mexico. A third grade fuel bonate and bicarbonate, is preferred for oil is obtained from Mexican Gulf fields. the operation of the plant. The concen Electricity costs 6 to 7 ce tavos a kw.-hr. trated brine from the center of the solar evaporator is pumped into a ditch, through Details of this project are contained in which it flows about half a mile to storage Mineral Trade Notes, Vol. 55, N o . 1, ob tanks at the alkali plant. From the tanks tainable from the Economics and Statis it passes to four carbonating towers about tics Branch, U. S. Bureau of Mines, Wash 100 feet tall where, at a temperature of ington 25, D . C. about 122° F., it passes down over Colombian Alkali Industry baffles counter cur Officials of the Instituto de Fomento Industrial, an, agency rent to a stream of of the Colombian government, and representatives of carbon dioxide gas. the H. f t . Ferguson Co., Cleveland, Ohio, discuss plans for the $9 million alkali industry to be erected in the Bogota The crystals ob area. There tvill be a 100-ton soda ash plant, a 50-ton tained, containing dense ash plant, and facilities for caustic, chlorine, re" about 1 6 % water fined salt, and bicarbonate of soda production· after washing, are Left to right are A. L. Campbell, R. C. Smith, J. deD. either sold in bulk Ceballos, and Carlos Gomes or further processed to make sodium bicarbonate. T h e lime from the kilns is used in the manufacture of caustic soda. The carbon dioxide from the kilns is filtered and washed. The light soda ash obtained a t this M A R C H
2 9,
1948
953
