The country’s earning textiles sector is also responsible for increased pollution.
By 2021, this sector will release 34 crore cubic meters of waste into water.
A recent research titled ‘Evaluation of Present and Future Wastewater Impacts of Textile Dyeing Industries in Bangladesh’ conducted by Chemical Engineering Department of Bangladesh University of Engineering and Technology (BUET) showed how much waste will be produced from garments and textile industries.
The research showed, in 2016 textile industries in Bangladesh produced about 1.80 million metric tons of fabric, which generated around 21.70 crore cubic meters of wastewater, and 23.80 crore in the next year. At the end of this year, the wastewater will stand at 26.30 crore cubic meters.
On the other hand, Bangladesh has produced 300 million square feet of leather in 2016 which had generated around 30 million cubic meters of wastewater.
As per the government target, to achieve the $5 billion export target, 35 percent annual production growth is required for the next five years (2017-2021). This will generate more wastewater at the same time.
If technological advancement is adopted, wastewater volume will be reduced to 15 million cubic meters in 2021, with 20 percent annual growth (present annual growth rate).
The research showed, textile-leather- garments industries are using large amounts of water. Use of water on the one hand reduces underground water-level, while on the other following use, it is thrown into canals and rivers without treatment. This wastewater is reducing oxygen percentage in the water and increasing threat to aquatic animals.
According to the research, the rivers and water of Dhaka, Narayanganj and Gazipur regions are the most polluted as these areas have heavy textile industries.
Many villages of Gazipur and the Dhaka-Narayanganj-Demra (DND) dam area are now facing serious threat due to water emanating from the textile industries. Besides, due to the pollution of Shitalakkhya river, people are being threatened by death due to use of contaminated water in the region.
The study has taken into account the pollution trend of textile industry from 2011 to 2021. Based on the one decade pollution level and measure, it has found that during 2016 a total of 18 crore clothes were produced, increasing gradually in the following years. By 2021, wastewater amount will increase by 60 percent.
But effective technical use can reduce the wastewater by 23 percent, the study showed. Improving conventional technology, adopting cleaner production (CP) options, the reusing and recycling of treated water may reduce water consumption, effluent volume and water stresses, and may help preserve aquatic ecosystems.
In the study, a database with wastewater volume and pollution load for leather industries has been developed. A material balance approach has been used to calculate the current and future pollution load contributed by the leather sector by analyzing the pollution load database, current production capacity, projection of future expansion and technological advancements.
It also states that tannery industries in Bangladesh cause a range of environmental problems, including water pollution. Tannery industries are water intensive. Effluents from this industry contain various chemicals such as oil, grease, chloride, chromium, sulphates, aluminium, zirconium, sodium, calcium and other toxic substances. Typical characteristics of tannery industry wastewater generally include a wide range of pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), heavy metals and strong color.
During 2011, wastewater production from knit industry was 7.50 crore cubic meters. At the same year, woven industry wastewater was 7 crore cubic meters. Last year knit industry generated 11.40 crore cubic meters wastewater while woven industry, 12.40 cubic meters. In 2021, knit and woven industry will produce 16.70 crore and 18.20 crore cubic meters gradually.
On the other hand, the department of environment has informed, the country’s largest export earning sector’s pollution is also high. Each year, pollution from this sector is rising. The entrepreneurs of the sector also count many penalties due to pollution. But in recent times, environmental awareness of this industry has risen; many factories have already established central effluent treatment plant (CEPT).
But in reality, even though the CEPTs are there, many of them remain inactive.