572 T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY Vol. 14, No. 6

Wool Scouring Wastes for Fertilizer Purposes (Correction)

In my article under the above title [THIS JOURNAL, 14 (1922),

Report of Committee on Occupational Diseases in the Chemical Trades

(Correction) In the Report on page 456 of the May issue of THIS JOURNAL 4341 attention is called to the following error:

2nd col., 2nd para., 4th line, reading “degreased wnste contains 24.5 per cent EGO, 24.6 per cent nitrogen, etc.,” should be corrected to read “de- greased waste contains 24.6 per cent Ki0, 2.5 per cent nitrogen.”

2nd para., lines 2 and 3, delete “and industries;” 6th para., line 5, for “trained” read “engaged.’>

LEWIS W. FETZER, Chairman F. P. VEITCH UNIVERSITY OF DALLAS

WASHINGTON, D. C . DALLAS, TEXAS May 4, 1922 May 9, 1922

LONDON LETTER B y HUGH GRIFFITHS, 15 New Bridge St., London, E. C . 4 , England

KEY INDUSTRIES BILL As was expected, the interpretation of the Key Industries Bill

is giving rise to discussion. Various appeals have been heard, the most interesting being that in connection with cream of tartar, tartaric acid, and citric acid. The decision turned on the interpretation of the expression “fine chemical” and the Referee in giving his decision that these substances could not be con- sidered as fine chemicals, and should therefore be excluded from the Act, stated that he had found that there is no commonly accepted definition of a fine chemical, and he could only be guided by trade usage. Lactose “R” has also been excluded from the list.

A most interesting application was made by the agents of an American firm, to have mucic acid removed from the list, men- tion being made of a new process for producing this substance in large quantities as a substitute for cream of tartar. This appeal was dismissed on the ground that mucic acid had to be considered as a fine chemical a t the date of passing the Act.

Applications have also been made to have calcium carbide and liquid sulfur dioxide included in the list. These applications were also dismissed, although a mass of evidence was collected and given by eminent scientists in support of the former applica- tion. At the time of writing, synthetic camphor and pinene are under consideration, an application having been made to have these removed from the list. In spite of the elaborate provisions of this Act, there is but little sign of revival in the chemical trade, and there is an increasing tendency to avoid new developments of any kind.

SYNTHETIC AMMONIA Of all the developments in chemical industry which must be

considered as of national. importance, those concerning the fixa- tion of atmospheric nitrogen are the most essential. It is some- what disturbing, therefore, to hear rumors that none of the schemes for the manufacture of synthetic ammonia are really being pushed forward. There is a very persistent rumor that all constructional work on these plants has been stopped. If this rumor be true, the sympathy of every technical man will be ex- tended to those who have done so much to the development of these processes in this country. It is generally felt that money which is being found and spent in other directions might well be devoted to this work, and i t is hoped that government support will be forthcoming.

SODIUM SILICATE In the March letter, a reference was made to a new method

of manufacturing sodium silicate. There are several methods having the same object. The object of these methods is to con- vert the difficultly soluble fusion mass into a form of solid sodium silicate which can be dissolved readily without the use of large quantities of water, and without the use of pressure vessels. Most of these methods are the subjects of patents. Not only do these methods serve entirely to cut out the evaporation process, but they yield solid silicates, both of neutral and alkaline con- stitution, which can be transported in the solid form and dis- solved by the user as required; the saving in transport charges being considerable.

EVAPORATING PLANTS

Considerable interest is being shown in the various evaporating plants which operate on the principle of the reversed heat engine. This principle as applied to technical evaporation is by no means new, and suggested methods date back almost as far as the multiple effect plant. There are now on the market plants according to several different systems, and an English company has been established to handle one type of installation, i. e., the Prache and Bouillon system.

Up to the present the number of these plants in use in this country is not very large, but an evaporator according to this system, of considerable size, is in use in a glue works in the north of England, and certain power stations are installing water distil- ling plants a t the present time according to the same principle.

The deluge of patent applications from abroad relating to “thermo-compression’’ is very significant, and, coupled with the fact that the makers of these plants will now give satisfactory guarantees as to steam or energy consumption, these plants have to be considered as definite competitors against the multiple effect apparatus.

Some firms will guarantee the same steam economy in a single vessel working a t ordinary atmospheric pressure as can be ob- tained with a triple effect; there should therefore be some pros- pect that recompression evaporators will be able to enter the field at very competitive prices, but a t the present time they are somewhat expensive, and, for the same performance, higher in price than multiple effect plants.

hTEUTRAL SULFATE OF AMMONIA

The manufacture of sulfate of ammonia is a t last being defi- nitely subjected to radical changes. Manufacturers have gone considerably out of their way to educate the consumer against the ordinary quality of sulfate. It is definitely recognized that a neutral sulfate in a sandy dry form would possess many advan- tages in practical use, and the consumers are now beginning to show interest and are looking for this material instead of the ordinary quality. The inevitable discussion has arisen as to the best method of manufacturing this neutral sulfate, and numerous patents have been taken out to protect modifications in the processes, neutralization by ammonia gas, ammoniacal liquor, or alkaline salts being proposed and effected in many different ways.

It is apparent, however, that the manufacturers are not quite so pleased with themselves now that they have to produce this material commercially, particularly as most of them find it necessary to instal new plant.

Most of the troubles manufacturers have had seem to be due to their reluctance to spend money on new plant a t a time when business is not bright.

There does not appear to be the slightest technical difficulty in making neutral sulfate of ammonia, and it is generally expected that in course of time all sulfate will be delivered in the neutral form, and the time will come when the consumer who will pur- chase the ordinary quality of sulfate will be forgotten.

’

April 13, 1922