Microplastics have grown to be a significant environmental issue. These are little plastic particles, measuring less than 5 mm. The focus primarily has been on oceans and consumer products, however, the role of industrial wastewater in microplastic pollution is coming into the limelight. In this article, we will look at the scale at which the problem exists, its challenges, and some solutions. 

Microplastics In Industrial Wastewater: The Scale of the Problem

Microplastics in industrial wastewater show far-reaching implications for the ecosystem and also human health. Let us understand its prevalence in this section:

Sources of Industrial Microplastics

Microplastics in industrial wastewater are seen from various sources. Moreover, each of these sources shows a different kind of challenge: 

• Textile Industry: During the manufacturing and washing processes, synthetic fibers tend to shed. It leads to a significant amount of microplastic pollution. This is because each time a synthetic cloth goes through washing, thousands of microfibres are released into the wastewater systems. 

• Cosmetics and Personal Care: Many products have microbeads for exfoliation purposes. These are banned in some countries, however, these tiny particles are still seen majorly in industrial processes. 

• Manufacturing: the production of plastic materials often results in the release of pellets of plastic, powders, and fragments in the wastewater streams.

• Packaging Industry: The breaking down of materials of plastic packaging during the production and recycling processes often generates microplastics in industrial wastewater. 

• Agriculture: The agricultural settings see major use of plastic mulch films and the breakdown of plastic items. This, in turn, contributes to microplastic pollution in runoff and wastewater. 

Environmental Impact

There are huge consequences that microplastics in industrial wastewater show toward the environment:

• Aquatic Ecosystem Disruption: Microplastics are often ingested by marine life. So, this leads to physical harm. It also causes a potential bioaccumulation of toxins up the food chain. 

• Soil Contamination: When wastewater comes in use for irrigation or when sludge is used as fertilizers, microplastics accumulate in the soil. As a result, it affects the health of the soil and enters the food chain through crops. 

• Air Pollution: The microplastics containing dried wastewater sludge can become airborne. As a result, it can cause atmospheric microplastic pollution. 

• Waste Resource Contamination: Microplastics have the tendency to infiltrate groundwater and surface water resources. This can affect the supply of drinking water. 

Challenges in Microplastic Removal

The engineers and researchers are working constantly to battle the challenges that removing wastewater microplastics from industrial wastewater brings. Let’s see some of these challenges ahead:

Detection and Quantification

One of the major challenges seen in addressing the pollution of microplastics is detecting and quantification of particles in wastewater:

• Size Variability: Microplastics often show a range of 5mm right down to the nanometer scale. This makes its detection across this wide size range difficult through a single method. Furthermore, nanoplastics that are 100 nanometers pose an even bigger challenge. This is because it crosses the biological barriers more easily compared to the larger particles. As a result, this raises concerns regarding the impact on human health. 

• Chemical Diversity: There are over 20 different types of plastic in use in an industry. So, this makes it complicated to identify and quantify the efforts. Furthermore, each of these types shows different chemical properties and degradation patterns. As a result, it makes it necessary to use sophisticated analytical techniques to accurately identify it. 

• Complex Matrices: Industrial wastewater shows a mix of organic and inorganic materials. So, this makes it a challenge to isolate and identify the microplastics. Furthermore, the existence of natural particles can interfere with microplastic detection. Moreover, it leads to false positives or negatives. It also complicates the accurate assessment of contamination levels. 

• Lack of Standardization: Currently, there is no method of quantifying microplastics in industrial wastewater that is universal. So, it makes comparisons between studies and industries a challenge. Furthermore, this lack of standardization leads to a major variation in reported microplastic concentrations. This hinders effective policymaking and treatment strategies across regions and industries.

Removal Efficiency

The wastewater treatment plants that exist were not made with microplastic removal in mind. This causes several challenges:

• Conventional Treatment Limitations: the traditional wastewater treatment processes are ineffective in removing small microplastics/nanoparticles. Furthermore, studies reflect that these conventional treatment plants may only remove 50-80% of microplastics. Moreover, the small particles are likely just to pass through and enter the environment.

• High Flow Rates: Industrial wastewater treatment requires large volumes. This makes it challenging to execute fine filtration without a major drop in pressure or clogging issues. Moreover, there are some industries that produce millions of liters of wastewater almost daily. So, they require a system that can handle high throughput. This is without compromising the efficiency of microplastic removal.

• Chemical Resistance: Many microplastics show resistance to chemical and biological degradation processes that are there in the treatment of wastewater. So, this resistance causes the accumulation of microplastics in treatment plant sludge. This can then be applied to the agricultural land as fertilizer making a second path for environmental contamination. 

• Cost Considerations: It is expensive to use advanced treatment technologies for microplastic removal. This is especially the case for industries that are small in size. Furthermore, the cost of upgrading a treatment plant can run into millions of dollars for effectiveness. So, this can come up as a major barrier for businesses and municipalities. 

Microplastics in Industrial Wastewater:  Innovative Solutions 

Even though there are several challenges along the path of wastewater treatment, there are some innovative solutions to address the problem as well. So, let us see in this section what they are:

Advanced Filtration Technologies

There are several new filtration technologies that are going through development to target microplastics specifically:

• Membrane Bioreactors (MBRs): There are systems that make a combination of biological treatment and membrane filtration. So, it shows promise in removing a major percentage of microplastics. Furthermore, there are some MBR systems that show removal rates up to 99.9% for microplastics that are greater than 0.1 μm. So, it is one of the most powerful microplastic removal technologies in wastewater treatment for industrial applications. 

• Nanofiltration and Reverse Osmosis: These are some advanced membrane technologies that can remove the smallest of particles. Furthermore, they require major energy output for it but are highly effective. Moreover, they can have high costs for operations due to the membrane fouling. As a result, it makes it necessary to conduct a cost-benefit analysis for implementing it. 

• Electrocoagulation: This process makes use of electrical current to coagulate and remove the microplastics in industrial wastewater. This reflects great efficiency in pilot studies. Furthermore, it has the added benefit of removing other pollutants as well like heavy metals. Moreover, it is more cost-effective than the traditional chemical coagulation. As a result, it is an attractive option for multi-pollutant treatment. 

Biological Treatment Methods

There are some innovative biological approaches that make use of the power of nature to solve the challenges of microplastics in industrial wastewater:

• Microplastic-Eating Bacteria: Researchers have found bacterial strains to be effective in degrading a few types of microplastics. Furthermore, they offer a biological treatment option. For example – Ideonella sakaiensis can break down PET plastic. Moreover, others have shown great effectiveness in degrading polyethylene and polystyrene. So, it opens up some significant possibilities for targeted strategies of bioremediation. 

• Engineered Enzymes: Enzymes that are custom-designed can break down certain plastics after development. Furthermore, these work faster and more efficiently than naturally occurring bacteria. As a result, it speeds up the biodegradation process and gives a scalable option for applications in the industry. 

• Algal Systems: There is some research that reflects that specific kinds of algae can absorb and degrade microplastics in industrial wastewater. So, this offers two benefits – wastewater treatment and also biomass production. Furthermore, these treatment systems can also sequester carbon dioxide. As a result, it gives an extra environmental benefit and revenue stream through the carbon credits. 

Source Reduction Strategies

The best strategy is to stop the micro plastics from even entering the wastewater:

• Alternative Materials: Many industries are looking at biodegradable alternatives to traditional plastics. This is especially the case for single-use items and packaging. Furthermore, bioplastics are gaining popularity. This is because they are made of materials like cornstarch or sugarcane. However, their complete biodegradability in different environments is still going through some research and requires a life cycle assessment. 

• Process Optimization: It stands for improving manufacturing processes to reduce plastic waste and the generation of microplastics during production. Furthermore, some companies are using closed-loop manufacturing systems. These capture and reuse plastic particles. As a result, it majorly reduces microplastic emissions and improves the efficiency of resources.

• Closed-Loop Systems: It is a system that uses water recycling and reuse within industrial processes. Furthermore, this minimizes the release of microplastics in the environment. They not only reduce microplastic pollution but also lead to major water and cost savings for industries. So, this makes it a great option for sustainable water management. 

• Policy and Regulation: Govt. is going toward stricter regulations on microplastic use and discharge. So, this is driving innovation in prevention and also treatment. For instance, the EU is making a policy framework that addresses microplastic pollution. This includes potential bans on intentionally adding microplastics to products. Moreover, it will likely spur some global action and innovation within the field. 

To Sum Up

The challenge of microplastics in industrial wastewater is layered and complex. It requires great efforts from the industry, researchers, and also policymakers. Furthermore, though there are major hurdles, innovative solutions exist for mitigating its growing environmental threat. To go deeper into these cutting-edge solutions and connect with the industry leads who are at the forefront of industrial wastewater management, make sure you attend the Industrial Water & Wastewater Management Summit. It takes place on September 26-27, 2024, in Frankfurt, Germany. Through participation, you will get rare insights into water treatment and water stewardship, treatment of process water, industrial water infrastructure, and more. So, don’t miss the opportunity!