PAKISTAN is now increasingly exploiting commercial value of cotton waste, thanks to broader use of improved technology in ginning and cotton yarn making that allows accurate separation of bulk and minute wastage.

A Karachi based exporter of cotton waste products told Dawn that Pakistan exports cotton and cotton yarn waste to a number of countries, most notably to China, Hong Kong, US, UK, France, Germany, Italy, Spain, Belgium, Netherland and Russia and earns about $75-$100 million a year.

He said that exports of cotton and cotton yarn waste to China are estimated to have doubled and crossed $20 million mark in FY13 because in Chinese ginning factories, the percentage of wastage is lower than in Pakistan and Chinese traders import, our cotton and yarn wastages to use them in machine cleaning industry and also for making value-added products.

Cotton ginning waste is also being used in some countries in building materials like wall boards, insulation boards, shingles, cinder blocks etc. But in Pakistan lack of investment required to turn cotton gin waste into building material continues to impede progress in this direction. In some countries like US and China, cotton gin waste has also been used as material for manufacturing of three-dimensional molded composite boards for use as decorative doors, furniture pieces, cabinets, etc.

But in Pakistan such things are not done even on experimental basis because of the lack of financial and technological resources. Wooden furniture makers say that a combination of cotton ginning waste, wooden particles that accumulate during furniture making and wooden fibres can be combined to produce better quality household furniture but that too requires sizable initial investment in developing technological and human expertise.

Ginners say that they pay somewhere between Rs250 and Rs300 per bale of cotton gin waste to haulers who take away the wastages from ginneries adding that the rate depends upon the volumes of hauling.

Agricultural officials say that when cotton is ginned, seed cotton cleaners separate the heavier and coarser portion of the foreign matter including leaves, burs (carpel), stems, sticks, and soil particles from the seed cotton. Lint is separated from the seed at the gin stand. Some burs, small trash, and motes (immature seeds) are also removed.

“The lint is subsequently cleaned by line cleaners which remove leaf particles, dust and other small trash, as well as motes and short fibre. The two types of wastes, i.e., fragments, sticks and other plant parts removed before ginning and the linty material known as motes are considered as waste products,” explains one of the officials of Sindh Agriculture Department.

Many cotton ginners in Sindh and Punjab now run compact ginning units that separate solid cotton waste and finer impurities. The wastage is piled up at specific places and then transported to contractors for onward sales. Most of such contractors also work for textile mills where finer cotton wastage like broken yarn threads and fabric trashes pile up during the process of yarn manufacturing or cloth making.

Some of these contractors manufacture basic cotton waste products like mop ropes, dish cleaners, rugs and foot mats. Others sell the cotton and yarn waste to specialised manufacturing units that produce products of higher commercial value like pharmaceutical grade non-woven fabric or cotton buds for ear cleansing.

Recycled cotton waste is also supplied to manufacturers of sport goods for producing low quality batting pads, hand gloves and chest pads. Likewise, balls of broken cotton threads and cuttings of cotton cloth come handy in cleaning of machines of all kinds and are vastly used by motorcycle and car mechanics. In clothing industry, cotton waste is used for inner padding of low quality leather and canvas jackets.

In areas close to ginning factories and in adjoining rural areas, people buy cotton waste to use it in pillows and quilts after recycling the same through traditional measures.

Cotton ginners say that during ginning process, 20 to 30 per cent of the total amount of ginned cotton make up all kinds of wastages, depending upon the make, model and age of the ginning machinery. The bulk of the waste is in the form of cotton balls containing hard impurities like stuck-up cotton seeds and weeds. Such cotton waste is used by quilt and pillow makers more commonly as their traditional hand-held ginning instruments are capable of removing such impurities.

But finer impurities like dust and dew droplets need more sophisticated recycling processes for removal and cotton contaminated with such impurities go to cities where recyclers do their job and use cleaned cotton for making households, industrial and commercial products.Cotton growers point towards another important use of cotton ginning waste. They say that some of them use such waste for making a thin layer of bedding in cotton fields adding that cotton grown over such fields normally gives higher yields.

A detailed study on uses of cotton waste carried out by federally run Agricultural Policy Institute suggests that the factor behind higher yields is the increased water holding capacity of the soil after the spreading of cotton waste over it. Farmers also point out that in the areas along cotton growing belt, cotton waste, mixed with fodder fibres is often used as livestock feed.

There are some other more sophisticated uses of cotton and yarn waste that remain unexplored in our country but are becoming popular in advanced economies. For example, cotton dust is used for firing boilers; solid cotton waste is incinerated for heat recovery to reenergise gin dryers. —Mohiuddin Aazim