Advanced Treatment of PLA MPs Using SATOORNIK Gen-I

By: Dr.-Ing. Mitra Nikpay

Funded by SATOORNIK UG

© [24.03.2025] Dr. Mitra Nikpay and SATOORNIK UG. All rights reserved. No part of this report may be reproduced, distributed, or used without proper authorization.

INTRODUCTION

Polylactic acid (PLA) is one of the most well-known, environmentally friendly, biodegradable, biocompatible, and biobased polyesters. As the global shift towards sustainable materials accelerates, the demand for PLA has risen significantly in recent years. For example, the production of PLA has been expanding at about 10-15% annually. This growth indicates that the release of PLA microplastics (MPs) into the environment is also likely to increase. With the rise of PLA's usage, concerns are mounting about its contribution to plastic waste, making PLA an emerging environmental contaminant [1, 4].

Recent studies highlight the role of PLA MPs in the broader context of plastic pollution, focusing on their potential to carry organic and inorganic pollutants into ecosystems. PLA MPs may pose a significant threat to aquatic and terrestrial environments, especially as they degrade into smaller particles. For instance, PLA’s ability to adsorb various pollutants, including hazardous metals and organic chemicals, could contribute to the spread of these contaminants, further intensifying the pollution problem [2,3].

Bioplastics like PLA, while often marketed as safer alternatives to conventional plastics, raise significant concerns about their potential toxicity. As PLA degrades, it forms bio-microplastics (BMPs) that can be ingested through food or water, posing health risks. Studies show that PLA-MPs, when exposed to organisms like mice, cause greater weight inhibition, oxidative stress, and disruptions in gene expression, particularly affecting the liver and digestive systems. PLA-Nanoplastics (PLA-NPLs) have also been shown to damage intestinal cells, and induce oxidative stress, DNA damage, and inflammation. These findings highlight the need for more research to fully understand the environmental and health impacts of bioplastics, as their widespread use may unintentionally contribute to new health and ecological risks [2,4,5,6].

Despite the increasing production and use of PLA, the environmental behavior of PLA MPs remains an area of concern. PLA biodegrades relatively slowly and incompletely under natural environmental conditions, and this degradation rate is significantly slower when compared to other materials. While PLA can biodegrade in industrial composting environments under controlled conditions, the process takes up to 90 days to degrade over 90%. However, in less controlled environments, such as home composting systems or marine and freshwater ecosystems, PLA can persist for much longer, contributing to the growing presence of microplastics in nature. The incomplete biodegradation of PLA in these environments suggests the potential for long-term accumulation, further exacerbating the microplastic pollution issue [7].

Considering these concerns, the development and application of efficient separation and filtration technologies are crucial to addressing the rising presence of microplastics in contaminated water sources. In this context, the present study aims to evaluate the effectiveness of the SATOORNIK Gen-I filtration system in removing PLA microplastics from contaminated water. Preliminary results demonstrate a significant removal efficiency, achieving an average reduction of 99.80% across three test conditions. The mass of microplastics captured through this process is equivalent to levels typically found in thousands of liters of polluted water, underscoring the potential scalability of this technology for industrial and municipal wastewater treatment applications.

MATERIALS AND METHODS

PLA Particles:

Three distinct tests were conducted using different PLA particle samples. The Tests utilized PLA particles purchased from the market which is 100% PLA material. The quantities of PLA particles used in each test are summarized in Table 1.

Table 1 Sample properties used in the tests

Figure 1 displays microscopic images of PLA materials used in the tests. The size distribution of the PLA particles applied in tests is shown in Figure 2. The mean particle size was 85 µm and the lowest size measured 18 µm. The densities of the PLA particles were 1.25 g/cm³. Each test was conducted with 500 mL of tap water mixed with the respective PLA particles to create a controlled medium for evaluating filtration efficiency. The water samples were agitated thoroughly to ensure uniform particle distribution before testing.

Figure 1 Microscopic images of PLA materials used in tests.

Figure 2 Graph of the particle size distribution for PLA samples used in tests

SATOORNIK Gen-I Filtration System:

The SATOORNIK Gen-I is a full-scale filtration unit specifically designed for the continuous separation of microplastics, including PLA particles. Engineered for high efficiency, the system is optimized to capture even the smallest particles in water.

For each of the three tests, 500 mL water samples containing PLA particles were processed through the SATOORNIK Gen-I system. The system operated continuously throughout the testing, with no washing or maintenance performed between tests. This approach aimed to evaluate the system's performance over multiple cycles, simulating real-world conditions of continuous operation.

Sampling and Analysis:

Samples were collected before and after filtration for each of the three tests. The pre-filtration sample represented the initial condition of the water, while the post-filtration sample represented the water after passing through the filtration unit.

The results were visually confirmed using a microscope. The comparison between the pre- and post-filtration samples allowed for the evaluation of the filtration efficiency in removing the PLA particles.

Results

The filtration efficiency of SATOORNIK Gen-I was evaluated by measuring particle concentrations before and after filtration. The high-efficiency percentage mean of 99.76% demonstrates the device's effectiveness in removing two different particles from water (See Table 2).

Table 2 Summary of Filtration Efficiency for SATOORNIK Gen-I Across Tests T1, T2, and T3

Comparison to Real-World Wastewater Treatment Plant (WWTP) Concentrations

The filtration efficiency of the SATOORNIK Gen-I system was tested across three samples of PLA particles, with masses of as Table 1. The system achieved high filtration efficiencies, ranging from 99.56% to 99.97%, with increasing particle concentrations reflecting real-world microplastic pollution levels.

In each test, PLA particle concentrations were significantly higher than typical wastewater treatment plant (WWTP) influent concentrations, calculated up to a 1198-fold increase relative to the real-world benchmark of 102 µg/L.

This cumulative test load equates to 2378 liters of real-world polluted water, indicating that the SATOORNIK Gen-I was able to handle continuous high-contamination levels effectively without requiring device maintenance or cleaning between tests. This result emphasizes the device’s robustness in treating PLA pollution at elevated concentrations typically found in industrial wastewater.

 The graph of Figure 3. demonstrates the robust filtration performance of the SATOORNIK Gen-I over three sequential high-concentration tests (T1, T2, T3), showcasing its ability to maintain or slightly improve efficiency under continuous operation. The data highlights the high filtration efficiency of the SATOORNIK Gen-I system, exceeding 99.97 % across all tests.

Figure 3. Efficiency of SATOORNIK Gen-I across three test samples. The graph demonstrates the consistent performance of the filtration system, with efficiency ranging from 99.56% to 99.97%, confirming its effectiveness in removing PLA particles across multiple tests.

Conclusion

The findings of this study demonstrate that the SATOORNIK Gen-I filtration system, tested at full-scale operation, is a highly effective solution for mitigating PLA microplastic pollution in both environmental and industrial contexts. Despite the use of PLA particle concentrations far exceeding typical real-world pollution levels, the system consistently achieved outstanding filtration efficiencies, averaging over 99.80 %, and reduced particle concentrations to near undetectable levels across all tests. This exceptional performance was maintained under varying particle masses and test conditions, underscoring the reliability and robustness of the technology.

The full-scale testing offers valuable insights into the practical application of the SATOORNIK Gen-I system for addressing PLA pollution, a growing concern in both industrial waste streams and environmental contamination. As PLA microplastics present significant challenges to wastewater treatment facilities and ecosystems, the system's success highlights its potential to combat critical environmental and public health issues.

Furthermore, the tests confirmed the system’s ability to operate continuously without any decline in performance, emphasizing its suitability for long-term, uninterrupted use in a variety of real-world settings. In conclusion, the SATOORNIK Gen-I filtration system emerges as a transformative solution for addressing PLA microplastic pollution, contributing to cleaner water, healthier ecosystems, and a more sustainable future.

REFERENCES

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