Effective Wastewater Treatment for Textile & Dye Industries

Did you know that 17-20% of industrial water pollution comes from the textile dyeing and finishing industries?

They are considered one of the largest wastewater producers because a large amount of water is required for various processes.

According to recent reports, the global textile industry uses around 79 billion cubic meters of water annually, and by 2030, this is expected to increase by 50%.

With the rise in fast fashion and increased textile production, untreated wastewater discharge remains a significant environmental concern.

The effluents the industry releases contain biodegradable and non-biodegradable contents that create environmental issues, affecting aquatic plants, animals, and human health.

There are natural, pocket-friendly treatment solutions to remove toxins from water before releasing it into the natural water body.

Recent studies indicate that modern wastewater treatment technologies can remove up to 90% of dye contaminants, yet nearly 80% of textile wastewater globally is still discharged untreated, particularly in developing countries.

But before getting into that, let’s understand the characteristics of the effluent present in wastewater from the textile industry.

Understanding the Characteristics of the Effluents

The textile industry is divided into three major sectors: Cotton, Woolen & Synthetic.

The divisions are made because industries that use different fibers consume different kinds of artificial dyes and chemicals, and follow different processes.

Some of the processes include pre-treatment, dyeing and printing, and finishing.

The primary pollutants are organic, including pulp pre-treatment, cotton gum, cellulose, hemicellulose, carcinogenic dyes, and other printing processes.

Studies show that 15–20% of dyes used in textile dyeing do not bind to fabrics and end up in wastewater, making wastewater treatment crucial to reducing water pollution.

The wastewater released by textile industries contains high levels of color, BOD, COD, salt, TSS, and TDs, which are most contaminated by toxic chemicals and dyes.

Hence, it is critically important to treat wastewater before releasing it to maintain a balance in the ecosystem.

Some of the effective ways to treat wastewater are:

1. Physicochemical Method
2. Chemical Method
3. Biological Method

Physicochemical Method

This treatment is most commonly used to remove high levels of chroma and suspended substances.

The processes in the physicochemical method are:

• Equalization and homogenization: Pre-treating the polluted wastewater is essential before it reaches the regulating tank. The process prevents materials such as lint, cottonseed shells, and slurry from settling at the bottom of the tank. The wastewater is mixed with air or mechanical mixing equipment.
• Floatation: The second step in treating the wastewater is with the help of floatation. The process produces large amounts of microbubbles to form three substances: water, gas, and solids. Under the effect, the microbubbles adhere to the tiny fibers and are effectively removed from the wastewater.
• Coagulation, flocculation, sedimentation: In this process, heterogeneous matters are removed with the help of mechanical separation. Dissolved matter cannot be adequately removed in this process, but can be removed with the help of biological or physical-chemical processes.

Chemical Method

In this treatment, chemicals are applied to help separate contaminants from water or neutralize/destroy the harmful effects of pollutants.

Currently, Fenton oxidation and ozone oxidation are often used in wastewater treatment:

1. Fenton Reaction: The Fenton reaction is a commonly used chemical method for treating textile effluent, where decolorization is the primary concern. The oxidizing agent is the leading chemical, Hydrogen peroxide (H2O2), which activates the most potent existing oxidizing agent, the hydroxyl radical. The Fenton reaction is used as a pre-treatment.
2. Ozone Oxidation: This treatment is effective and fast at decolorization; it can either inhibit or destroy the properties of residual surfactants and oxidize a portion of the COD. The process is suitable for improving the biodegradability of textile effluents, which contain many toxic and non-biodegradable components.
3. Adsorption: One of the most commonly used physicochemical wastewater treatment methods is adsorption. The process can efficiently adsorb and remove pollutants from the filter surface.
4. Membrane Separation Process: Membrane separation is the process of filtering using membrane micropores. The treatment is mainly used to treat dyeing wastewater via reverse osmosis, ultrafiltration, nanofiltration, and microfiltration.
   • Reverse osmosis: Reverse osmosis removes mineral salts, hydrolyzed reactive dyes, and chemical auxiliaries.
   • Nanofiltration: This process is applied to treat coloured effluents from the textile industry. The filtration process decreases concentration polarizing with highly concentrated and complex solutions.
   • Ultrafiltration: Ultrafiltration is the process of eliminating macromolecules and particles such as pollutants, but the process doesn’t eliminate the polluting substances.
   • Microfiltration: The process used to treat bath dyes, which contain pigment dyes. The treatment can be used as a pre-treatment for nanofiltration or reverse osmosis.

Biological Wastewater Treatment Method

Biological wastewater treatment effectively degrades the organic matter in effluent from organic dye industries.

Biological treatment methods are divided into aerobic and anaerobic processes.

• Aerobic Biological Treatment

Aerobic biological treatment helps purify wastewater using aerobic and facultative bacteria.

The process has many benefits in reducing high COD/BOD in effluent waters containing high TDS.

Many aerobic solutions are available in the industry, but Organica Biotech offers an effective microbial solution for aerobic wastewater treatment, with microbes that can thrive in high TDS effluents.

After conducting years of research, we developed a revolutionary product, Cleanmaxx ANB, an effective biological aerobic wastewater treatment solution.

The bacterial strains in Cleanmaxx ANB are capable of rapid biomass development and can withstand fluctuations in wastewater quality.

It accelerates COD/BOD reduction, rapidly reduces the time required for effective aerobic wastewater treatment, and reduces energy spent in aeration & agitation, thereby cutting CAPEX/OPEX costs.

Are you splurging on unnecessary maintenance costs in your treatment plant?

Reach out to our wastewater experts for an effective solution that causes no harm to the environment!