The wastewater comes from the chemical cleaning of boilers, pipelines, heat exchangers, and other equipment where scale, corrosion products, and organic deposits accumulate. Although cleaning restores equipment performance, it produces a complex liquid waste containing organic compounds, ammonia nitrogen, dissolved salts, metal ions, and substantial moisture. Conventional treatment can be technically demanding and expensive, particularly when compounds such as ethylenediaminetetraacetic acid, or EDTA, are present. Because coal-fired boilers already operate at high temperatures, researchers are investigating whether they can serve as existing thermal-destruction systems for this challenging waste.

In a study published in Energy & Environment Nexus, researchers from Southeast University examined how organic cleaning wastewater changes the ignition, mass-loss behavior, burnout, and reaction kinetics of bituminous coal. They prepared coal blends containing 1%, 3%, 5%, and 10% wastewater by weight and analyzed them using non-isothermal thermogravimetric analysis. This technique continuously measures changes in sample mass as temperature rises at controlled heating rates, allowing scientists to identify when ignition begins, how rapidly volatile and fixed carbon components react, and when combustion is completed.

The results showed that low and moderate wastewater additions could significantly reduce the temperature required to ignite the coal. At a heating rate of 10 °C per minute, untreated coal ignited at approximately 411.6 °C. When wastewater was added, the ignition temperature fell as low as 390.6 °C. The researchers attribute this shift to the combined influence of oxygen-containing organic compounds and inorganic species, particularly iron and sodium. These components may promote early oxidation reactions or assist in the breakdown of oxygen-containing functional groups on the coal surface, creating a more reactive environment during the initial stages of heating.

The strongest kinetic improvement occurred at a 5% wastewater ratio. For untreated coal, the average apparent activation energy was calculated at 131.68 kilojoules per mole. In the 5% blend, it dropped to 115.92 kilojoules per mole, indicating that less energy was needed to initiate the dominant combustion reactions. The 10% blend showed an intermediate value of 122.77 kilojoules per mole. Apparent activation energy is not a direct measurement of one isolated chemical reaction; rather, it summarizes the energy barrier associated with the overall reaction pathway observed under the experimental conditions. Even so, the trend suggests that moderate wastewater loading can improve the early reactivity of coal.

The apparent benefit, however, did not continue indefinitely. As the wastewater proportion increased, the maximum and average mass-loss rates generally declined, and overall combustion performance fell by approximately 4% to 15% under several test conditions. Moisture in the wastewater absorbs heat during evaporation, reducing the energy available for oxidation. Its dissolved salts and mineral matter also dilute the combustible fraction of the blend. As heating proceeds, inorganic residues may accumulate around coal particles and form a denser layer, restricting oxygen transport to the particle surface and slowing the final burnout stage.

The 10% blend made this inhibitory effect especially visible. At heating rates of 20 and 40 °C per minute, the burnout temperature increased, meaning that the coal-wastewater mixture required a higher temperature to complete combustion. This behavior reflects the competing mechanisms inside the heated particle. Organic compounds and metal species may accelerate initial oxidation, but water evaporation, fuel dilution, and ash-related diffusion resistance can dominate later. The study therefore presents wastewater not as a universally beneficial combustion additive, but as a chemically complex material whose effect depends strongly on concentration and operating conditions.

“Our results show that organic cleaning wastewater does not simply promote or suppress coal combustion,” corresponding author Yaji Huang said. “Its effects depend strongly on the blending ratio and result from a balance between catalytic substances and components that absorb heat or restrict oxygen transfer.” According to the researchers, a moderate addition may provide a practical compromise between easier ignition and stable combustion, whereas excessive loading should be avoided. The 5% blend delivered the lowest average activation energy among the tested mixtures, but that result does not by itself establish an optimal operating ratio for a commercial boiler.

The findings could open a new pathway for industrial waste management by combining wastewater disposal with an existing energy infrastructure. In principle, high-temperature combustion could destroy hazardous organic compounds while reducing the need for a separate treatment facility. Yet the laboratory evidence is only an initial step. Full-scale trials must determine how the wastewater affects nitrogen oxide and other pollutant emissions, ash composition, slagging, fouling, boiler corrosion, and the long-term reliability of fuel-feeding systems. The researchers also emphasize the need to verify whether all organic contaminants are destroyed and whether metals or salts become concentrated in the resulting ash. Until those questions are answered, co-firing should be viewed as a promising but tightly controlled engineering option rather than a ready-made solution.

Subject of Research: Combustion behavior and reaction kinetics of bituminous coal blended with organic cleaning wastewater.

Article Title: Combustion characteristics and thermokinetics of coal blended with organic cleaning wastewater

News Publication Date: 30 June 2026

Web References: Energy & Environment Nexus: https://doi.org/10.48130/een-0026-0012

References: Zhang J, Huang Y, Qiu Y, Jiang X, Zhang L, et al. 2026. “Combustion characteristics and thermokinetics of coal blended with organic cleaning wastewater.” Energy & Environment Nexus 2: e018. DOI: 10.48130/een-0026-0012

Image Credits: Jun Zhang, Yaji Huang, Yizhuo Qiu, Xinyi Jiang, Lanpeng Zhang and Hao Shi

Keywords

Coal combustion, organic cleaning wastewater, wastewater treatment, thermokinetics, apparent activation energy, bituminous coal, thermogravimetric analysis, industrial boilers, EDTA, co-disposal, combustion kinetics, energy and environment

Researchers at The University of Manchester have shown that microbial communities from terrestrial hot springs could be harnessed to convert industrial CO₂ emissions into useful products, offering new routes towards a circular, low-carbon economy.

Industrial processes such as steel and cement production generate large volumes of CO₂-rich waste gases. While these emissions are a major environmental challenge, the new study – published in Environmental Microbiome – suggests they could represent an untapped resource.

The team found that microbiomes inhabiting terrestrial hot springs are naturally adapted to conditions that closely resemble industrial waste streams: high temperatures, elevated concentrations of CO₂, and chemically challenging environments.

Hot spring microorganisms are highly efficient at transforming inorganic carbon, including CO₂, into organic compounds such as biomass and other valuable products. The researchers suggest that these communities could form the foundation of new biotechnologies designed to operate under industrial conditions without the need for light or energy-intensive cooling processes.

Such approaches could enable the production of value-added compounds, including biopolymers and vitamins, directly from CO₂-rich waste streams, helping to reduce emissions while generating economic value. 

While geological carbon storage remains a critical component of Net Zero strategies, it can be energy-intensive and costly to implement at scale. The researchers suggest that biotechnological approaches could offer a complementary route by converting emissions into useful products rather than storing them underground.

The study is based on a global analysis of hot spring microbiomes spanning multiple continents, revealing consistent metabolic potential for carbon transformation across diverse environments.

Corresponding author, Professor Sophie Nixon, states:

“This study highlights that nature has already evolved solutions for converting CO₂ under extreme conditions, and that these natural solutions are there for us to harness.

Our work sits alongside geological storage within a broader portfolio of CO₂ management strategies. The key difference is that here, we’re going beyond just storing carbon, and transforming it into something useful.

This is a proof of concept, and we are now actively working with these communities in the laboratory to develop scalable, cost-effective systems that can contribute to Net Zero.”

This paper was published in the journal: Environmental Microbiome

Full title: Exploring the biotechnological potential of terrestrial hot spring microbiomes for CO₂ utilisation

DOI: https://doi.org/10.1186/s40793-026-00875-x 

Journal

Environmental Microbiome

DOI

10.1186/s40793-026-00875-x

Chlorobenzene, a commonly used solvent in the manufacturing sector, poses significant health risks due to its associated toxicity and environmental persistence. The need for efficient methods of removal has never been more urgent, as the release of such compounds can lead to severe consequences for air quality and public health. The study highlights the advances made in biotechnological approaches to mitigate this issue, showcasing the application of magnetically enhanced microbial activity in biotrickling filters.

Utilizing biotrickling filters is not a new concept; however, elevating this technology with enhanced packing materials and external magnetic fields is a novel step forward. The research reveals how these modified packings improve the contact between microbes and the target pollutant, leading to a more efficient degradation process. By increasing the surface area available for microbial colonization, the study demonstrates that the efficiency of chlorobenzene removal can be significantly amplified.

The introduction of a magnetic field plays a crucial role in this innovative approach. Magnetic fields can influence microbial behavior and enhance metabolic processes within biofilms that develop on the packing materials. This provides a synergistic effect, where the magnetic field not only supports microbial growth but also catalyzes the degradation of chlorobenzene through advanced bio-remedial mechanisms. Understanding these intricate interactions is essential for optimizing the use of biotrickling filters in practical applications.

The results of the study are compelling. Through the use of modified packings and a precisely calibrated magnetic field, the research team reported remarkable increases in chlorobenzene removal rates. Their experimental setup demonstrated a marked improvement over traditional biotrickling methods, confirming that alterations in physical packing structures can profoundly benefit microbial efficiency. Notably, this enhancement offers a dual advantage: it not only expedites the removal process but also reduces the overall footprint of the biotreatment system.

Moreover, the implications of these findings extend beyond just chlorobenzene removal. The methodologies developed in this study could be adapted to address other pollutants that present similar challenges, potentially revolutionizing how industries approach VOC management. This adaptability underscores the potential for widespread applicability within various sectors, including petrochemicals and pharmaceuticals, where chlorobenzene and similar compounds are prevalent.

The microbial mechanisms that underpin this enhanced performance also warrant attention. Detailed investigations into the metabolic pathways activated under strong magnetic fields revealed a notable acceleration in the biodegradation processes. Understanding these pathways offers invaluable insights into optimizing bioremediation technologies, guiding future research toward the development of even more potent environmental cleanup strategies.

Furthermore, the results observed in this study provide a foundational basis for scaling the technology for real-world applications. With regulatory pressures increasing for industries to minimize emissions and waste, this novel technique aligns perfectly with global sustainability goals. As companies strive to comply with stricter environmental standards, innovations like the one presented by Chen and colleagues represent not just scientific progress, but also a roadmap for industry adaptation.

The collaboration between researchers and industry is crucial in bringing these laboratory findings into practice. Future studies should focus on pilot projects to test the viability of such biotrickling filter systems in diverse operational environments, establishing benchmarks for performance against existing technologies. This progression from research to application requires careful consideration of factors such as cost, ease of integration, and long-term sustainability.

In addition to industrial applications, the implications of this study reach public health and safety domains. As VOCs like chlorobenzene remain a concern for air quality, the effectiveness of these innovative solutions could lead to healthier living environments, ultimately contributing to broader public health benefits. The intersection of science, technology, and public health underscores the importance of continued investment in environmental research.

In conclusion, Chen et al.’s exploration into enhanced gaseous chlorobenzene removal using modified packings and magnetic fields within a biotrickling filter represents a significant advancement in environmental engineering. The potential to revolutionize air quality management and reduce toxic emissions heralds a futuristic approach to addressing industrial pollution, setting a precedent for further innovations in the field.

Researchers are optimistic that with increased funding and collaboration, the findings will inspire further developments in bioremediation sciences. The overarching goal is to create more efficient systems that can cope with complex and variable pollutant scenarios, setting high standards for environmental sustainability. Overall, this pioneering study stands as a beacon of hope for scientists dedicated to making our planet safer and cleaner.

Subject of Research: Enhanced gaseous chlorobenzene removal via innovative modified packings and magnetic field.

Article Title: Enhanced gaseous chlorobenzene removal and its microbial mechanism through innovative modified packings coupled with magnetic field in a biotrickling filter.

Article References:

Chen, D., Qiu, J., Meng, C. et al. Enhanced gaseous chlorobenzene removal and its microbial mechanism through innovative modified packings coupled with magnetic field in a biotrickling filter. Front. Environ. Sci. Eng. 19, 152 (2025). https://doi.org/10.1007/s11783-025-2072-x

Image Credits: AI Generated

DOI: 30 August 2025

Keywords: chlorobenzene, biotrickling filter, gaseous removal, microbial mechanisms, magnetic field, environmental remediation.

Coal fly ash is produced during the combustion of coal in thermal power plants. The byproduct is rich in various elements, including aluminum and silicon, which are essential building blocks for creating nanoparticles with diverse applications, ranging from electronics to medicine. The conventional perception of coal fly ash as merely waste is being upended by emerging studies that illustrate its potential for creating high-value materials. The conversion of this waste into usable resources not only mitigates environmental concerns but also paves the way for innovative solutions in material science.

Nanoparticles are materials with dimensions less than 100 nanometers, possessing unique physical and chemical properties that differ significantly from their bulk counterparts. The ability to manipulate these properties allows scientists and engineers to develop applications that can revolutionize various fields, including catalysis, drug delivery, and environmental remediation. By extracting aluminum and silicon from coal fly ash, researchers are creating a pathway to harness these properties in a sustainable manner.

The extraction processes for aluminum and silicon from coal fly ash are varied, involving either physical or chemical methods. The chemical approaches generally utilize acidic or alkaline solutions to solubilize these metals, enabling their recovery from the complex matrix of fly ash. A cardinal challenge lies in optimizing these processes to enhance the yield and purity of the extracted materials. Minimal processing and lower operational costs are crucial for making this approach economically viable.

Furthermore, the purity of the extracted aluminum and silicon is paramount, as impurities can significantly affect the functionality of the resulting nanoparticles. Advanced techniques such as high-resolution transmission electron microscopy (HR-TEM) and X-ray diffraction (XRD) are employed to evaluate the structural integrity and quality of the nanoparticles synthesized from these materials. High purity is essential, as it ensures the desired characteristics of the nanoparticles are achieved, which is crucial for their intended applications.

One potential application of aluminum and silicon nanoparticles derived from coal fly ash is in the domain of catalysts. Nanoparticles have shown remarkable capabilities in promoting chemical reactions while reducing energy consumption. By leveraging the unique characteristics of these materials, researchers are investigating their use in various catalytic processes, including those involved in energy production and environmental remediation. The ability to recycle waste materials into efficient catalysts is an attractive prospect for both economic and environmental sustainability.

Moreover, the role of nanoparticles in the pharmaceutical industry cannot be overstated. The unique properties of aluminum and silicon nanoparticles can be harnessed for drug delivery systems, improving the bioavailability of therapeutic agents. By encapsulating drugs within these nanoparticles, researchers can enhance targeted delivery, resulting in more effective treatments with fewer side effects. This innovative approach exemplifies how repurposing waste can yield advancements in healthcare.

The development of environmentally friendly materials is increasingly vital as industries seek to minimize their carbon footprint and lead to a greener future. The findings from Tenza and Aphane’s review underscore the importance of integrating sustainability into material science. By transforming coal fly ash into functional nanoparticles, the study aligns with global initiatives aimed at reducing waste and creating sustainable materials.

However, the transition from laboratory experiments to industrial applications poses challenges that must be addressed. Scaling up the extraction and synthesis processes requires significant investment in technology and research. Collaborative efforts between academia, industry, and government agencies are essential to develop processes that are not only efficient but also economically feasible.

Public awareness and acceptance also play a crucial role in the adoption of these technologies. As communities become more informed about the benefits of converting industrial waste into valuable resources, the likelihood of successful implementation increases. Educational initiatives highlighting both the environmental and economic advantages of utilizing materials like coal fly ash can foster greater support for such advancements.

In conclusion, the research conducted by Tenza and Aphane on the extraction of aluminum and silicon from coal fly ash presents a promising frontier in the quest for sustainable materials. This innovative approach not only addresses the pressing issue of industrial waste management but also opens avenues for technological advancements across various sectors. As the demand for environmentally friendly solutions continues to rise, the transformation of waste into nanoparticles stands as a beacon of hope. This intersection of sustainability and technology exemplifies how deliberate efforts can yield remarkable outcomes, turning challenges into opportunities for a better future.

As we look ahead, the implications of this research extend beyond just the scientific community. It serves as a comprehensive blueprint for industries looking to innovate responsibly, pairing resource efficiency with ecological stewardship. In a world where the pressure to balance progress with sustainability is more pronounced than ever, the insights gleaned from coal fly ash offer a pathway to a more sustainable and technologically advanced future.

Subject of Research: Coal fly ash-derived aluminum and silicon for nanoparticle synthesis

Article Title: Coal fly ash industrial waste-derived products: a review on the extraction of aluminum and silicon for nanoparticle synthesis.

Article References: Tenza, N.P., Aphane, M.E. Coal fly ash industrial waste-derived products: a review on the extraction of aluminum and silicon for nanoparticle synthesis. Environ Sci Pollut Res (2026). https://doi.org/10.1007/s11356-025-37298-z

Image Credits: AI Generated

DOI: https://doi.org/10.1007/s11356-025-37298-z

Keywords: coal fly ash, nanoparticles, aluminum extraction, silicon extraction, sustainability, industrial waste, material science