Rayon textile operations

Workers employed at facilities that manufacture or use hydrogen sulfide in the production process are especially prone to exposure. Such industries include the manufacture of rayon textiles, lubricants, pulp and paper, and sulfuric acid and inorganic sulfides. Workers in facilities where hydrogen sulfide is produced as a byproduct, such as farms with manure storage pits, petroleum or natural gas drilling operations, landfills, and waste-water treatment plants, may also be exposed to high levels. 

After the filament rayon fiber has been spun and chemically purified, much of it passes through what are known as textile operations before it is ready to be knitted or woven. Because these steps of twisting and packaging or beaming are common to the manufacture of all manufactured fibers, it is advisable to review briefly the background and the processes. 

The continuous process for spinning and purifying textile-grade rayon yarn merits particular mention from the standpoint of industrial chemistry, as it is rather an axiom that a continuous process is to be preferred over a batch or discontinuous operation. This method employs advancing rolls or godets that make it possible for the yam to dwell for a sufficient length of time on each pair, thus allowing the several chemical operations to take place in a relatively small area. Their... 

The textile industry is characterized by a host of journals that are marginal in the sense that they contain a little bit of everything. For example, Modern Textiles Magazine (46) y formerly known as Rayon and Synthetic Textiles usually contains some articles on fairly fundamental research in man-made fibers or textiles. Besides this, the journal contains at various times articles for mill operating personnel, articles on dyeing, production and consumption statistics, articles on new equipment, yarn prices, and similar material that could be of interest to almost anyone in the industry. 

The viscose obtained from Cross and Bevan was so successful for production of lamp filaments that Steam asked Topham to try to spin it for use in textiles. The first experiments failed dismally. After several years of painstaking work, Topham made several discoveries essential to the spinning of yam from viscose aging (ripening) of the solution, filtration to remove particles, multiple-hole platinum spinnerettes, and a circular, centrifugally operated yarn collecting device that twisted the yam and packaged it in convenient cake form [117]. The Topham box, as it is still called, or variations of it are still on many of the continuous-filament rayon machines today. 

Textile wastewaters can vary from slightly acid to highly alkaline depending on the individual processes carried out within the plant. They generally are alkaline when caustic scouring or mercerizing is involved. Heavy metals such as copper, chromium and zinc result from the use of certain dye carriers in the dyeing operation of synthetic fabrics and of blended fabrics, e.g., cotton and rayon. The pretreatment unit operations which may be necessary for various types of joint treatment facilities are listed in Table 6. 

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