Wet processing engineering

Wet Processing Engineering is one of the major streams in textile engineering refers to textile chemicals process engineering and applied science. The other three streams in textile engineering are yarn engineering, fabric engineering and apparel engineering.

Wet process is usually done on the manufactured assembly of interlacing fibers, filaments, and/or yarns having substantial surface (planar) area in relation to its thickness, and adequate mechanical strength to give it a cohesive structure. In other words, wet process is done on manufactured fabric. The processes of this stream is involved or carried out in aqueous stage and thus it is called wet process which usually covers pretreatment, dyeing, printing and finishing.

All of these stages are required aqueous medium which is created by water. A massive amount of water is required in these processes per day. It is estimated that, on an average, almost 100 liter of water is used to process only 1 kg of textile goods. Water can be of various quality and attributes. Not all water can be used in the textile process, it must have some certain properties, quality, color & attributes for being used in textile processes. This is why water is a prime concern in wet process engineering.

Most water used in the textile industry is from deep well water which is found 800 ft below the surface level. The main problem which is concerned in using water in textile processes is water hardness caused by the presence of soluble salts of metals including calcium and magnesium. Iron, aluminum and copper salts may also contribute to the hardness, but their effects are much less. Using hard water in wet process can cause problems such as the formation of scale in boilers, reactions with soap and detergents, reaction with dyes and problems due to Iron.

Water hardness can be removed by boiling process, liming process, sodalime process, base exchange process or synthetic ion exchange process. Recently some companies have started harvesting rain water for use in wet processes as it is less likely to cause the problems associated with water hardness.

Wet Process Engineering (WPE) is the most significant division in the textile preparation and processing. It is a major stream in textile engineering which is under the section of textile chemical processing engineering and applied science. Textile manufacturing covers everything from fiber to apparel; covering with yarn, fabric, fabric dyeing, printing, finishing, garments or apparel manufacturing. There are many variable processes available at the spinning and fabric-forming stages coupled with the complexities of the finishing and coloration processes to the production of a wide ranges of products.

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