SAFETY
M a k i n g Handling of Acetylene Safer Chemische W e r k e Huls installs special e q u i p m e n t to reduce h a z a r d of explosion in a c e t y l e n e pipelines MARL, GERMANY.-Import.int new safety measures have been taken here at Chemische Werke Huls to prevent recurrence of a disastrous explosion which blasted large areas oJLjlie plant early this year. Rupture disKs7 decomposition barriers, and electrically operated, quick-closing devices are being installed throughout the reconstructed acetylene pipe network. In the Hiils plant, raw acetylene manufactured in the gasworks is piped to a purifying plant where higher acetlyenes are separated by a refrigeration process. Semipurifled acetylene is then piped to a desulfurizing plant and from there to a gasholder. Gasholder supplies an acetaldehyde unit, and vinyl chloride and tetrachloroethane factories receive dry acetylene directly from the purifying plant. New Year's Day explosions damaged in part or completely two sections of acetylene-purifying plant, desulfurizing plant, gasholder, and the pure acetylene pipeline. Fire broke out at 15 different places. It was extinguished only after the Hiils fire brigade and voluntary fire brigades of Marl, Recklinghausen, and Gelsenkirchen-Buer were called into action. Thirty-three people suffered minor injuries. A sudden drop in atmospheric temperature caused the raw ethylene pipeline to burst and escaping gas was ignited by a spark believed to have been caused by the burst metal or by static loading. The ethylene explosion caused an immediate shutdown of the tetrachloroethane factory, which resulted in an unexpected reaction between chlorine and acetylene. This was the start of a chain of explosions in the acetylene pipeline. A similar explosion occurred in the Buna Werke Schkopau following a bombing attack during the last war. In reconstructing the pipeline, every elbow has been replaced by a full cross, the ends of which are closed with rupture disks designed to release at a pressure of 1.5 atmospheres. The rupture disks have been galvanized on the outside for corrosion resistance. Disks are not expected to stop an acetylene decomposition once it has started, but Chief Engineer Max Gugger points out that they will have such a powerful retarding effect that decomposition barriers installed in front of production works and gasholder should become effective.
Towers, 6 meters higri, filled with 15-mm. Raschig rings, seirve as decomposition barriers. In two cases, instead of the Raschig ring towers, 6-meterlong tube bundles have been used. In the main feed pipe, bundles of tubes with 10-mm. o.d. and 1-mm. wall thickness have been installed. In cases where wet acetylene can be used in processing, Raschig ring towers are continuously sprinkled with water. Operating pressure for t h e acetylene pipeline has been limited to 250 mm. of water. In front of the cylinder filling stations, electrically operated remote quick closing devices h a v e been installed. These are immersion apparatus with electromagnetic bell closing devices which shut off gas conduits within one to two seconds. Htils engineers are also building a test pipe length in which acetylene explosions will be studied. Safety devices now installed in tJhe production plant will be examined for effectiveness in this test length.
Job Injuries Termed a National Disgrace at President's Meeting WASHINGTON.-Occupational injuries and deaths, with their ensuing hardships and economic losses, were termed "a national disgrace" b y Secretary of Labor James P. Mitchell at t h e opening session of the President's Conference on Occupational Safety. Mitchell told the conference, sponsored by his department's Bureau of Labor Standards, that t l i e problem of occupational safety was an ever growing one and that it would require the best efforts of all to be solved. Mitchell cited 1953 and 1952 injury figures to support his statement. In 1953 there were 6000 more injuries in manufacturing, construction, utilities, trade, service, and Government than there were in 1952. Total disabling injuries in 1953 were 1,458,000. In addition he noted an increase of 100 deaths over 1952 to a total of 8900. "These figures are a measure of the j o b before us," Mitchell said. Mitchell's words were reinforced by remarks to the conference by President Eisenhower earlier in the day. The President said he had officially approved the conference because he was CHEMICAL
appalled by the toll occupational accidents are taking in this country. H e asked for an all-out effort to reduce accidents. He especially called on the conference to concentrate on combating accidents apparently often brought about by lack of training or by carelessness. Mitchell later said that "Americans are becoming increasingly safety conscious" and are demanding that something be done about the problem. H e asked that hard won knowledge gained through experience in safety work by the members of the conference be p u t to work on a national basis and along concentrated lines. To this end h e pledged help and active assistance of his department. Mitchell also said that too little attention has been paid to safety in the area of Government and public employment. For its part, he announced, the Federal Government has set u p new field safety organizations to work in the areas where most accidents occur. H e expressed hope that state and local officials in attendance would adopt some of the safety efforts the conference was undertaking to promote.
Seven Workers Develop Chlorocne in Plant Using Arochlor Lesions of chloracne developed in seven workers employed in an organic acid manufacturing plant when Arochlor was used as a heat exchange material around a large jacketed reaction chamber. For some months, the company had used molten salt but changed to the chlorinated diphenyl because of danger of solidification, as well as the corrosion problem. A slight leakage of vapors, particularly around the cover of a sump p u m p and from all gasketed connections in the system, was soon observed. A field study by the Connecticut State Health Department showed the air concentration of chlorinated diphenyls to be 0.1 mg. per cubic meter in breathing zones. Recommended maximum allowable concentration is 1.0. No one worked regularly at leakage points; nevertheless, repeated attempts were made to control the leakage, b u t without complete success. This operation continued for 19 months with no manifestations of exposure to chlorinated diphenyls. One of the workers then developed acute contact dermatitis; on examination, cysts and comedones on both cheeks and the forehead were noted. Chloracne was diagnosed. Examination of others in the same area uncovered six additional cases. Following recognition of these cases, AND
ENGINEERING
NEWS
all but one of the gasketed joints in the heat exchange system, including the cover of the sump, were welded together. A hand hole was left with a gasketed cover so the system could be drained or filled. Since then no vapors have been visible, and the odor of chlorinated diphenyls is barely detectable in the immediate vicinity of the sump. Continued observation of workers has revealed no new cases of chloracne. An unusual feature of this outbreak of dermatitis was the long period of exposure before any cases were recognized. Sudden recognition of seven cases after 19 months was a result of the especially careful examination of the exposed employees after discovery of the first case. Of 14 exposed or potentially exposed, seven developed chloracne. The fact that air tests, even in the presence of vapors, showed only negligible amounts of chlorinated hydrocarbons indicates that this type of intermittent but fairly long continued mild exposure is not innocuous. The low concentration of the chlorinated diphenyl might account for development of lesion only in 5 0 % of those involved. J. W. Meigs, J. J. Albom and B. L. Kartin, all of N e w Haven, Conn., report full details in the April 24 issue of / . Am. Med. Assoc.
• Air Reduction receives an award of merit from National Committee on Films for Safety. Its 20-minute welding safety film, "The Guy Behind Your Back," was honored in the occupational sound slidefilm class. Additional information on the film may b e obtained from Airco, 60 East 42nd St., N e w York 17, N. Y. • Eye protection against chemical splashes, flying particles, and light glare is offered by the MS A-Jones Visor Gog^ gles, according to Mine Safety Appliances. Design features are an opaque green visor perforated for open ventilation (or two-port screened for indirect ventilation) and readily interchangeable lenses. S1 • A film badge service is being offered by* Nuclear Instrument and Chemical. The plastic color-coded Nuclibadges are said to contain a special multiple filter system and an extremely wide range film packet, making possible evaluation of a wider range of ionizing radiations. Badges are furnished on a weekly basis and must b e returned to t h e company for processing. S 2
^
3 2,
NO.
20
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PHOSPHORUS (Yellow or White)
PHOSPHOROUS ACID
PHOSPHORUS OXYCHLORIDE
HYPOPHOSPHOROUS ACID
PHOSPHORUS TRICHLORIDE
ALKYL ACID PHOSPHATES (Alkyl Phosphoric Acids)
PHOSPHORUS PENTACHLORIDE PHOSPHORUS PENTASULFIDE
SODIUM CHLORATE
PHOSPHORUS SESQUISULPHIDE
POTASSIUM CHLORATE
AMORPHOUS PHOSPHORUS
POTASSIUM PERCHLORATE
PHOSPHORIC ANHYDRIDE
HYPOPHOSPHITES
PHOSPHORIC ACID
OXALIC ACID ZINC PHOSPHIDE
OLDBURY
ELECTRO-CHEMICAL COMPANY Plant and Main Office: NIAGARA FALLS, NEW YORK New York Office: 19 RECTOR STREET, NEW YORK 6, N. Y.
WEBCELL C O N T I N U O U S
DIALYSERS
TYPICAL LARGE BATTERY INSTALLATION OF WEBCELL DIALYSERS IN VISCOSE RAYON PLANT FOR THE RECOVERY OF CAUSTIC SODA
A nuMaxp
ta CHEMISTS & CHEMICAL ENGINEERS
Almost every industry that employs liquid in the process af manufacturing their product can benefit by DIALYSIS Because dialysis is a simple, gravity f e e d , low o p e r a t i n g cost process with proven economical application, it warrants investigation in many new fields of industrial use. In addition to production size equipment, we offer a l a b o r a t o r y model for experimental work that obtains results closely transl a t e d into terms o f production size expectancy. W e a r e also e q u i p p e d to make experimental tests in our own l a b o r a t o r y a n d invite your inquiry. .
For further information LABORATORY
write for Bulletin 5B
MODEL
BROSITES MACHINE COM PA N Y
For further information on the keyed items mentioned here, see coupon on page 2050 VOLUME
OLDBURY 1896 =
5 0 CHURCH STREET
(Cablfc Addrest — §ROMACH)
NEW YORK 7, N.Y.
rELEPHONE QIGBY J 9 - 3 6 0 0
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M A Y
17,
1954
2039
