A 30-ton large-scale treatment unit developed in-house by ECO-HOPIA
ECO-HOPIA announced that its sewage sludge valorization technology has been published in the SCI-indexed international journal Journal of Environmental Management. The paper reports an industrial-scale process that achieves complete compost maturation of sewage sludge in just 10 days, even under subzero winter conditions. This study is regarded as clear, international recognition that ECO-HOPIA’s process delivers world-leading performance at full scale.
The research was conducted at a commercial facility with a treatment capacity of 180 tons per day, using operational data collected across both summer and winter seasons. Even when the ambient temperature dropped below –1.8 °C in winter, the composting temperature rose above 70 °C (with a peak of approximately 72.5 °C). While conventional sewage sludge composting typically requires 45–60 days, the ECO-HOPIA system consistently completes the process in about 10 days, demonstrating the potential for year-round operation that is not constrained by seasonal climate conditions.
The study also confirmed the safety and quality of the final compost product. Pathogenic microorganisms such as Escherichia coli and Salmonella were not detected, heavy metal concentrations met relevant domestic and international fertilizer standards, and key parameters such as pH, moisture content, and C/N ratio fell within ranges suitable for agricultural use. In lettuce growth trials, plots amended with ECO-HOPIA compost showed a statistically significant increase in fresh biomass compared to the control, indicating that the rapidly processed material can still be converted into a high-quality resource suitable for agricultural applications.
Maintaining aerobic conditions throughout the process substantially reduced the potential for methane generation, another important outcome of the study. Compared with conventional landfilling, the ECO-HOPIA system was estimated to offer a potential reduction of several thousand to over ten thousand tonnes of CO₂-equivalent greenhouse gas emissions per year. The authors conclude that the technology should be viewed not merely as a sludge treatment method, but as a low-carbon infrastructure solution that contributes to climate change mitigation and the realization of a circular bioresource economy.
Dr. Huitae Min, Executive Leadership Division at ECO-HOPIA and co-corresponding author of the paper, commented, “Publication of this work in an SCI journal confirms that ECO-HOPIA’s sewage sludge valorization technology has been rigorously verified at an industrial scale, beyond the level of laboratory research. Achieving 10-day maturation under subzero conditions at full scale is an exceptionally rare case worldwide, and it demonstrates that ECO-HOPIA’s process is a highly competitive resource valorization platform in the global market.”
Building on this achievement, ECO-HOPIA plans to expand the application of its technology from sewage sludge to a wider range of organic waste streams, while further advancing its integrated valorization solutions for biogas, bio-solid fuels, and matured organic fertilizers. Under the vision of “Organic Waste, 100% Resource”, the company aims to actively deploy its solutions in both domestic and international markets.
Paper Information
- Title: Thermophilic composting of dewatered sewage sludge under subzero temperatures using a full-scale pre-fermentation reactor: A 10-day valorisation strategy for year-round operation
- Journal: Journal of Environmental Management (SCI)
- DOI: 10.1016/j.jenvman.2025.127997
This article is an ECO-HOPIA internal press release prepared by the company.
A 30-ton large-scale treatment unit developed in-house by ECO-HOPIA
ECO-HOPIA announced that its sewage sludge valorization technology has been published in the SCI-indexed international journal Journal of Environmental Management. The paper reports an industrial-scale process that achieves complete compost maturation of sewage sludge in just 10 days, even under subzero winter conditions. This study is regarded as clear, international recognition that ECO-HOPIA’s process delivers world-leading performance at full scale.
The research was conducted at a commercial facility with a treatment capacity of 180 tons per day, using operational data collected across both summer and winter seasons. Even when the ambient temperature dropped below –1.8 °C in winter, the composting temperature rose above 70 °C (with a peak of approximately 72.5 °C). While conventional sewage sludge composting typically requires 45–60 days, the ECO-HOPIA system consistently completes the process in about 10 days, demonstrating the potential for year-round operation that is not constrained by seasonal climate conditions.
The study also confirmed the safety and quality of the final compost product. Pathogenic microorganisms such as Escherichia coli and Salmonella were not detected, heavy metal concentrations met relevant domestic and international fertilizer standards, and key parameters such as pH, moisture content, and C/N ratio fell within ranges suitable for agricultural use. In lettuce growth trials, plots amended with ECO-HOPIA compost showed a statistically significant increase in fresh biomass compared to the control, indicating that the rapidly processed material can still be converted into a high-quality resource suitable for agricultural applications.
Maintaining aerobic conditions throughout the process substantially reduced the potential for methane generation, another important outcome of the study. Compared with conventional landfilling, the ECO-HOPIA system was estimated to offer a potential reduction of several thousand to over ten thousand tonnes of CO₂-equivalent greenhouse gas emissions per year. The authors conclude that the technology should be viewed not merely as a sludge treatment method, but as a low-carbon infrastructure solution that contributes to climate change mitigation and the realization of a circular bioresource economy.
Dr. Huitae Min, Executive Leadership Division at ECO-HOPIA and co-corresponding author of the paper, commented, “Publication of this work in an SCI journal confirms that ECO-HOPIA’s sewage sludge valorization technology has been rigorously verified at an industrial scale, beyond the level of laboratory research. Achieving 10-day maturation under subzero conditions at full scale is an exceptionally rare case worldwide, and it demonstrates that ECO-HOPIA’s process is a highly competitive resource valorization platform in the global market.”
Building on this achievement, ECO-HOPIA plans to expand the application of its technology from sewage sludge to a wider range of organic waste streams, while further advancing its integrated valorization solutions for biogas, bio-solid fuels, and matured organic fertilizers. Under the vision of “Organic Waste, 100% Resource”, the company aims to actively deploy its solutions in both domestic and international markets.
Paper Information
This article is an ECO-HOPIA internal press release prepared by the company.