Sewage Sludge Research Articles

Soft Soil Stabilization using Co-Pyrolytic Biochars from Sewage Sludge and Nymphaeale, an Invasive Plant Biomass

This research addresses a significant gap in current literature by proposing an alternative to traditional carbon positive soil stabilizers by utilizing sewage sludge in conjugation with Nymphaeale, an invasive plant biomass derived co-pyrolytic biochars to stabilize the soft soil, with a focus on understanding strength gaining mechanism. Various combinations of sewage sludge and Nymphaeale biomass underwent thermogravimetric analysis in a nitrogen environment, suggesting 450⁰C as pyrolysis temperature for biochar synthesis. Soft soil, which is considered problematic for construction, was blended with five distinct dosages (0%, 5%, 7.5%, 10%, and 12.5%) of biochars (BC75:25, BC50:50, BC25:75) by weight and unconfined compressive strength values were examined over curing periods of 1, 7, 14, and 28 days. The stress-strain and failure behaviour of soil-biochar mixes varied depending on the type of biochar used. SBC25:75 mixes exhibited ductile behaviour, whereas SBC75:25 mixes showed brittle failure. Furthermore, unconfined compressive strength values of soil-biochar mixes increased 4-5 times with maximum strength achieved at 10% dosage of BC50:50. Biochar dosages led to a reduction in moisture content and an increase in alkalinity and conductivity of the mixes, facilitating the initiation of pozzolanic reactions. The combined findings from the various analysis suggested that the presence of free oxides of calcium in biochars disrupted the laminated structure of the soil and reacted with silica and other aluminum silicates, resulting in the densification of the structure and the formation of cementing mineral phases in the mixes. Overall, the research-work emphasizes the idea of creating novel environmentally friendly binders for soil stabilization through the utilization of waste materials.

Multi-criteria evaluation of slurry fuels based on coal and organic waste

The applicability of slurry fuels for power generation by direct combustion was assessed using multi-criteria decision making (MCDM). Slurry fuels based on coal slime and water with 5% additive of biomass waste (rice husk, sawdust and sewage sludge) were studied. was experimentally established that the use of biomass waste in the composition of slurry fuel improves the characteristics of sedimentation stability by 2.5–4.2 times, atomization parameters by 1.5–2.0 times and environmental indicators of the combustion process by 1.5–2.4 times. A multi-criteria assessment of the efficiency of using slurry fuels in comparison with widely used solid fossil fuels in thermal power engineering was carried out based on the obtained experimental results. The indicators of the highest relative efficiency for slurry fuels with additives of sewage sludge and rice husk in the temperature range of 700–900 °C are 10–12% higher than for the composition without additives.

Evaluation of extraction and storage conditions for quantification and characterization of silver nanoparticles in complex samples by single particle-ICP-MS

The extraction of nanoparticles (NPs) from complex matrices and subsequent storage can potentially alter the NPs physicochemical properties and hinder cross-study comparisons. Most NP extraction methods are designed and tested at high nanoparticle concentrations, although (eco)toxicological and regulatory monitoring programs require methods capable of analyzing NPs at environmentally relevant concentrations (lower ppb range). In this study, we investigated how extraction methods affect the characteristics of PVP coated and citrate-stabilized silver NPs (AgNPs) spiked into soil, sewage sludge, and biological samples at environmentally relevant concentrations using Single Particle Inductively Coupled Plasma Mass Spectrometry spICP-MS). Further we investigated the impact of storage temperature (-80°C to 21°C) and storage duration (1-28 days) on the particle characteristics such as particle size.We found that aqueous AgNPs samples with low ionic strength media retained their original characteristics (like particle size, particle concentration and particle-based Ag mass) when preserved at 4°C for up to 28 days. AgNPs dispersed in high ionic strength media were however better preserved at -80°C. Among the extraction agents, tetrasodium pyrophosphate was more efficient in extracting AgNPs from soil and sewage sludge matrices, while Proteinase K was more suitable for biological samples from organisms (earthworms or fish).Although our study focused only on AgNPs, it provides crucial information to aid interlaboratory comparisons and data interpretation for (eco)toxicological studies.

Combustion behavior of solid waste fuels in the vertical tube reactor under different oxy-fuel environments

Oxy-fuel combustion technology has been recognized as one of the promising ways for cost-effective CO2 capture. The co-combustion characteristics of flax straw biomass/bituminous coal mixture (FS/BC) and flax straw biomass/sewage sludge mixture (FS/SS) under air, oxy-fuel (21%/79% O2/CO2) and oxygen-enriched oxy-fuel (30%/70% and 40%/60% O2/CO2) conditions were investigated in the vertical tube reactor. In particular, the study focused on the burning characteristics, the effect of blending ratio, and flue gas emissions. The findings indicated that flax straw biomass exhibited superior ignition performance compared to its blends with sewage sludge and bituminous coal. A higher O2 concentration from 21% to 40 led to a reduction in ignition delay time by 4s at 850 ℃ and by up to 10s at 950 ℃. Moreover, char combustion time was reduced by 50% for FS/SS blends due to the lower fixed carbon content compared to FS/BC blends. Additionally, increasing the O2 concentration resulted in lower emissions of CO by ∽40% and N2O by ∽45% for both blends. However, this also led to a slight increase in SO2 and NO emissions by ∽15% and ∽26%, respectively. The optimal conditions for the tested samples in oxy-fuel environment were found to be 30% O2/70 CO2, which enhanced combustion performance while lowering flue gas emissions.

Essential Quality Attributes of Culture Media Used as Substrates in the Sustainable Production of Pre-Basic Potato Seeds

The sustainability of the primary sector is closely linked to meeting the demand for seeds using agro-industrial waste and bioresidues. Sustainability is a multidimensional concept focused on achieving environmental health, social justice, and economic viability. To this end, an experiment was designed based on a combination of biotechnological strategies accessible to many individuals. The first strategy involves the use of compost and vermicompost as cultivation substrates; the second is the in vitro acclimatization of potato plants to these substrates; and the third is the incorporation of Trichoderma asperellum into these substrates to determine the synergistic effect of both. The compost used in this work came from sewage sludge from an agri-food company (Cp); a dining room and pruning waste from a university campus (Cu); and vermicomposted coffee pulp waste (Cv). Each sample was mixed with coconut fiber (Fc) in proportions of 100, 75, 50, and 25%. In the resulting mixtures, María Bonita variety vitroplants were planted and placed in a greenhouse. The biometric response in the three cases indicated a dependence on the type of compost and the proportion of the coconut fiber mixture. The inoculation of Trichoderma asperellum with sewage sludge compost increased stem thickness (42.58%) and mini-tuber weight (6.74%). In contrast, uninoculated treatments showed the best performance in terms of the number of mini-tubers. A 50:50 mixture of sewage sludge compost with coconut fiber and without inoculation of Trichoderma asperellum was the best treatment for the production of pre-basic seeds of the María Bonita potato variety. The use of composted agricultural waste and bioresidues is shown as a valid and low-cost alternative for the sector, even independently of the incorporation of additional inoculants.

Micro-plastics in soil environment: A review

Environmental scientists and other stakeholders have paid serious attention to soil pollution by microplastics in the last ten years. In soils, the microplastic particles act as a vector for the toxic persistent organic pollutants and potentially toxic metals that are easily sorbed by plants and enter the food chain. Microplastics are emerging as persistent terrestrial pollutants due to mismanagement and indiscriminate use. Microplastic contaminants affect the physicochemical characteristics of the soil as well as the feeding patterns of the soil biota. Sewage sludge, bio waste compost additions, plastic mulching, wastewater irrigation, landfill leachate, and air deposition are the causes of microplastics in soils. The amount of microplastics particles per kilogram of soil ranged from zero to thirteen thousand pieces. There are 523 times as many microplastic particles in the soil as there are in the ocean. Plant growth and seed germination are slowed down by the microplastic in the soil. Microplastics also affect the soil's enzymatic activities. The environmental sources of microplastic include plastic pellets, city dust, abrasion of road markings, tires, synthetic textiles, personal care products, and cosmetics. Human consumption through food can have a variety of harmful effects, including cytotoxicity, immunotoxicity, pulmonary toxicity, and reproductive toxicity. The current study describes the origins, distribution, and effects of microplastics on plants, soil biota, and human health in the soil environment. Bangladesh J. Nuclear Agric, 38(1): 1-19, 2024

Exploring acid mine drainage treatment through adsorption: a bibliometric analysis.

Discharge of acidic wastewater from mining activities (acid mine drainage (AMD)) is a major global environmental and public health issue. Although several approaches, including chemical precipitation and membrane technology, have been developed to treat AMD, adsorption has emerged as the most promising technology due to its cost-effectiveness and efficacy. Despite the wide adoption of adsorption in treating AMD, the evolution of research in this area remains poorly understood. To address this gap, a bibliometric analysis of the most recent literature involving the application of adsorption in AMD remediation was conducted by merging datasets of articles from Scopus (1127) and the Web of Science Core Collection (1422), over the past decade (2013-2022). This analysis revealed a yearly increase of 11% in research publications, primarily contributed by China, the United States, and South Africa. Keyword analysis revealed that natural schwertmannites and their transformations, activated carbon, zeolites, and clay minerals, are the most extensively employed adsorbents for the removal of common metals (arsenic, chromium, iron, manganese, among others). The findings underscore the need for future focuses on recovering rare earth elements, using nanoparticles and modified materials, pursuing low-cost, sustainable solutions, integrating hybrid technologies, pilot-scale studies, exploring circular economic applications of AMD sludges, and inter-continental collaborations. These insights hold significant future implications, serving as a valuable reference to stakeholders in the mining industry.

Enhancement of Marina Service Quality of Yacht Tourism in Taiwan: A Euclidean Distance of Importance-Performance Analysis

In spite of COVID-19 struck tourism industry, the trend of yachting tourism is steadily increasing and provides a way for the tourism industry to resume after the epidemic. Marinas, a vital component of yachting tourism, deeply effects the yacht owners’ satisfactions and the coastal destinations attraction. Since the marina industry in Taiwan is still in its early stages, this study aims to identify ideal service quality standards to enhance competitiveness. With a limited cohort of 69 yacht owners in Taiwan possessing yachts exceeding 20 gross register tonnage (GRT), insights from our research, which engaged perspectives from 50 yacht owners, provide valuable understanding into their satisfaction regarding marina services in Taiwan. As the first study to explore key factors of marina service experience among yacht owners, this study applies importance-performance analysis (IPA) and Euclidean distance to provide the development strategy and improvement priority of Taiwan marina service. Overall, the result from improving IPA technique which adopted Euclidean distance reveal that yacht owners generally thought that the improvement priority of marina service quality is sewage, bilge water, and oil sludge treatment facilities, fueling facilities, high-voltage shore power facilities, land storage space. It is noteworthy that marina managers should embark on improving marina physical facilities as development strategy which highlight the performance of marina service quality for yacht owners and the improvement in those facilities can be developed to either increase the marina competition or to resume tourism industry.

High-speed multi-stage gas-steam turbine with flow bleeding in a novel thermodynamic cycle for decarbonizing power generation

In the global pursuit of sustainable energy and reduced carbon footprints, advances in power generation techniques play a crucial role, not only in meeting the ever-increasing energy demands but also in ensuring that environmental standards are maintained and that the health of our planet is prioritized for future generations.In the ongoing quest for sustainable energy solutions, novel high-speed multi-stage gas-steam turbine models were designed to address the challenge of decarbonized power production. The thermodynamic parameters were adopted on the basis of the negative carbon dioxide gas power plant cycle relying on the following main devices, namely: wet combustion chamber, spray-ejector condenser, sewage sludge gasifier and gas-steam turbine. The peculiarities of the present system make the turbine the link of three important devices and its parameters affect the entire thermodynamic cycle. Therefore, it is reasonable to carry out dedicated novel in literature CFD calculations that also take into account the bleeding of the medium for the gasification process.Two distinct turbine models were introduced: a two-stage turbine achieving speeds of 95 000 rpm with an efficiency of more than 80%, and a five-stage turbine reaching 40 000 rpm with an efficiency of less than 70%. A design assumption of a bleed pressure of 100 kPa and a mass flow rate of 0.1 kg/s was adopted for both models. Computational simulations were utilized, and the turbine stages were selected with the aim of reducing energy losses. Through this work, a significant step towards a carbon-negative future using high-speed turbine technologies was demonstrated, laying the groundwork for further advancements in the field.

Stabilization of Sewage Sludge from North Moroccan Wastewater Treatment Plants Using Convective Indirect Solar Drying

Stabilization of Sewage Sludge from North Moroccan Wastewater Treatment Plants Using Convective Indirect Solar Drying

Relationship of CO2 adsorption performance and physicochemical property of biochar prepared by different types of biomass waste

The physicochemical property of biochar prepared by biomass waste is crucial for CO2 adsorption performance. However, the quantified relationship between the physicochemical property and CO2 adsorption capacity for biochar is still unclear. In this study, biochar samples with different physicochemical properties were prepared from six representative biomass of sewage sludge, chicken manure, apple and prickly ash branch, corn and rice straw. The quantitative investigation was conducted and the relationship between the physicochemical properties and CO2 adsorption capacity of biochar was analysed using Pearson correlation analysis method. The results showed that the biochar prepared from prickly ash branch at 800 °C pyrolysis exhibited a better CO2 adsorption capacity of 154.44mg/g and larger specific surface area of 160.83 m2/g, compared with other biochars. According to the quantitative data about physicochemical properties of twenty-four kinds of biochar samples, the correlations between CO2 adsorption capacity and microcrystalline structure, surface functional groups, nitrogen content and specific surface area were obtained. The CO2 adsorption capacity showed a significant positive correlation with the specific surface area (SBET),stacking height of aromatic layers (Lc), number of aromatic layers (N) and nitrogen content, and the correlation order was SBET >N >Lc = nitrogen content. Moreover, the CO2 adsorption capacity showed a negative correlation with diameter of aromatic planes (La), C=O, O-H and index of aromaticity (Aal/Aar), and the order of correlation was C=O > O-H >La >Aal/Aar. The effect mechanism of physicochemical properties on CO2 adsorption of biochar was that microcrystalline structure had an influence on CO2 adsorption by van der Waals force, and nitrogen, oxygen-containing functional groups, and so on by Lewis acid-base interaction and hydrogen bonding.

Enhancement of sulfur control by conditioners during sewage sludge pyrolysis: Focusing on screening and in-situ sulfur fixation mechanism based on model compounds

Utilizing conditioners is effective to reduce S-containing gases during sludge pyrolysis. Revealing the relationship between conditioners of different prices and multiple S control factors under similar conditions is key for efficient screening. However, a detailed performance comparison of conditioners remains unavailable. This study, for the first time, comprehensively compared the S control effect of six typical conditioners, and the model compounds of organic-S were used to reveal the in-situ S fixation mechanism of the conditioners. Results show that the total release of gas-S (especially H2S) decreased by 34.4∼54.2% after the addition of CaO, Fe2O3, and FeCl3. These conditioners (especially Fe2O3) can enhance the stepwise oxidation of easily decomposed organic-S (especially aliphatic-S) into stable sulfoxide-S and sulfone-S. Additionally, sulfide-S and sulfate-S can be generated via the capture of S-containing intermediates (i.e., ·SH) by conditioners (especially CaO). The presence of Cl can react with inorganic sulfide-S or organic-S via replacement, leading to the re-release of H2S. Among all conditioners, CaO, followed by Fe2O3 and FeCl3, showed the best comprehensive performance, especially in terms of price and effective H2S control temperature range. This work can guide the selection of conditioners for the synergistic control of S-containing gases in the integrated treatment of sludge.

Investigation of the agricultural reuse potential of urban wastewater and other resources derived by using membrane bioreactor technology within the circular economy framework

The European Union, as delineated in Regulation (EU) 2020/741, sets forth minimum criteria for the reuse of wastewater. Directive 86/278/CEE sets the regulations for the reuse of sewage sludge in agriculture. This study aimed to investigate the treated water derived from a pilot plant situated in Granada, Spain, that utilizes membrane bioreactor technology to process real urban wastewater with the quality standards necessary for agricultural reuse. Additionally, the study evaluated the utilization potential of other resources generated during wastewater treatment, including biogas and biostabilized sludge. The pilot plant incorporated a membrane bioreactor featuring four ultrafiltration membranes operating continuously alongside a sludge treatment line operating in batch mode. The pilot plant operated during four cycles, each with distinct hydraulic retention times (6 h and 12 h) and variable mixed liquor-suspended solids concentrations (ranging from 2688 mg L−1 to 7542 mg L−1). During these cycles, the plant was doped with increasing concentrations of emerging contamination compounds (diclofenac, ibuprofen, and erythromycin) to test their effect on the resources derived from the treatment. Subsequently, a tertiary treatment involving an advanced oxidation process was applied to the different water lines, which left the wastewater treatment plant for a period of 30 min and utilized varying concentrations of oxidant. The results indicate that the effluent obtained meets the required quality standards for agricultural use. Therefore, there is potential to use this waste as a resource, which is in line with the principles of the circular economy. Furthermore, the other resources generated during the treatment process, such as the biogas produced during the digestion process and the biostabilized sludge, have the potential to be used as resources according to the circular economy indicators.

Assessing the aerobic/anoxic enrichment efficiency at different C/N ratios: pilot scale polyhydroxyalkanoates production from waste activated sludge

Polyhydroxyalkanoates (PHA) can be produced using fermentation products of an excess sewage sludge fermentation process. An efficient method to enrich a PHA-producing community is an aerobic-feast/anoxic-famine enrichment strategy. The effect of different carbon to nitrogen (C/N) feed ratios of 1, 2 and 3.5 g COD/g N on the process performance was studied. The study was executed on a pilot plant scale using fermented waste activated sludge as the organic carbon source. The system's performance was monitored in terms of removing contaminants, producing PHA, and reducing N2O emissions. The results indicated that a lower C/N ratio results in lower PHA production, with PHA content in the sludge of 20, 24 and 36 % w/w for C/N ratios of 1, 2 and 3.5 g COD/g N, respectively. At the lowest C/N ratio, the highest nitrite accumulation rate (77%), nitrification efficiency (89%) and denitrification efficiency (89%) were observed, but the N2O production was also the highest (0.77 mg N2O-N/L). The long-term comprehensive monitoring carried out in this study revealed high carbon and ammonia removal efficiencies (never below 80%) despite the C/N shifts and high COD and ammonia concentrations. At the same time, the system showed relatively low PHA production and high environmental impact in terms of high gaseous N2O emission. These findings question the sustainability of the aerobic-feast/anoxic-famine enrichment strategy for PHA production in full-scale plants.

Исследование экологической безопасности автоклавного золопенобетона, полученного с использованием золы от сжигания осадка сточных вод

The article presents the research of ecological safety of autoclaved ash-foam concrete using ash from sewage sludge incineration in the constructed and operated production building. It is shown that after more than eighteen years of operation, the building made of autoclaved ash-foam concrete obtained using ash from sewage sludge incineration plant turned out to be environmentally safe for humans. Purpose: ash from sewage sludge incineration has high average specific radioactivity (radium and thorium), which strongly limits its further use. Earlier it was found that the use of ash from sewage sludge incineration as a raw material in autoclaved ash-foam concrete in different proportions affects the content of natural radionuclides in the finished product. The paper considers the environmental safety of autoclaved ash-foam concrete after prolonged operation. Methods: the research was carried out at the operating facility using a verified dosimeter-radiometer ATOMEX MKC-AT6130. Results: it was found that in all samples of autoclaved ash-foam concrete produced with ash from sewage sludge incineration the generated radiation background was below the norm, on the border of threshold values. Practical significance: the results of the work are important for construction, as they expand the ideas about the peculiarities of autoclaved ash-foam concrete and the possibility of safe use of ash from sewage sludge incineration in construction.

Effects of Sewage Sludge Biochar and a Seaweed Extract-Based Biostimulant on Soil Properties, Nutritional Status and Antioxidant Capacity of Lettuce Plants in a Saline Soil with the Risk of Alkalinization

Effects of Sewage Sludge Biochar and a Seaweed Extract-Based Biostimulant on Soil Properties, Nutritional Status and Antioxidant Capacity of Lettuce Plants in a Saline Soil with the Risk of Alkalinization

Airborne antibiotic resistome from sludge dewatering systems: Mobility, pathogen accessibility, cross-media migration propensity, impacting factors, and risks

Bioaerosol contamination was considered as a potential health threat in sludge dewatering systems (SDSs), while emission and risk of airborne antibiotic resistome remain largely unclear. Herein, seasonal investigations of fine particulate matter (PM2.5) were conducted using metagenomics-based methods within and around different SDSs, together with an analysis of sewage sludge. Featured with evident seasonality, antibiotic resistance genes (ARGs) in SDS-PM2.5 also possessed greater accumulation, transfer, and pathogen accessibility than those in ambient air PM2.5. Mobile ARGs in SDS-PM2.5 mainly encoded resistance to tetracycline, and most were flanked by integrase. Some pathogenic antibiotic resistant bacteria (PARB), including Enterobacter asburiae, Escherichia coli, Enterococcus faecium, and Staphylococcus aureus, also carried mobile genetic elements in SDS-PM2.5. Dewatering behavior actuated > 50.56% of ARG subtypes and > 42.86% of PARB in sewage sludge to aerosolize into air. Relative humidity, temperature, and PM2.5 concentration collectively drove the evolution of bacterial community and indirectly promoted the antibiotic resistance of SDS-PM2.5. SDS-PM2.5 posed more serious resistome risks than sewage sludge and ambient air PM2.5, and the highest levels were discovered in winter. These findings underline the role of dewatering behavior in facilitating resistome's aerosolization, and the need to mitigate this potential air pollution.

Changes in the soil microbial community 5 years after the application of sewage sludge biochar to soils cultivated with corn

AbstractBackgroundSewage sludge biochar has been widely used in agriculture for various purposes; however, knowledge about its residual effect on the soil microbial community is limited.AimsThis study aimed to evaluate changes in the microbial community 5 years after the application of sewage sludge biochar.MethodsBiochar was produced from sewage sludge obtained at a wastewater treatment pyrolyzed at 300°C (Biochar300) and 500°C (Biochar500). Both biochar treatments were applied in corn fields for two growing seasons (2014/2015; 2015/2016). Biochar was not applied from the third (2016/2017) to the seventh (2020/2021) growing season to assess the residual effect. Soil samples were collected after harvesting in 2020/2021 growing season, therefore in the fifth year subject to the residual effects of biochar. The microbial community was evaluated by accessing bacterial and fungal groups using DNA techniques. Amplicon sequencing analysis was performed with the samples by Illumina MiSeq 250 bp.ResultsAt genus level, the Lachnospira, Faecalibacterium, Bacteroides, Epulopiscium, and Parabacteroides were affected by Biochar500. Furthermore, at upper levels of taxonomy, this biochar treatment increased the relative abundance of bacterial classes Clostridiaceae and Bacteroidia and the fungal families Chaetomiaceae and Aspergillaceae. Concerning the relationship between microbial community and soil chemical properties, soil phosphorus (P) and calcium (Ca) were significantly affected by biochar treatments within the bacterial community; the fungal ones affected significantly soil P and potential acidity (H + Al).ConclusionsEven under the residual effect of 5 years, the application of biochar altered the microbial community on corn plantation, especially concerning on the richness and the abundance of some groups. Biochar500 was the most responsive among the treatments.

Syngas production and heavy metal dynamics during supercritical water gasification of sewage sludge

Syngas production and heavy metal dynamics during supercritical water gasification of sewage sludge

Contribution of distinct components in divergent organic amendments to long-term accumulation of soil organic matter in agricultural soils: evidence from thermally assisted hydrolysis and methylation-GC/MS.

Although maintaining/improving soil organic matter (SOM) quantity through utilizing organic amendments (OAs) is a productive practice, information on OA components contributing to long-term SOM accumulation in agricultural soils remains meager. Hence, we examined soil samples from a long-term experiment with different fertilizer managements, including no fertilizer (NF), chemical fertilizer (CF) only (CF), bark compost plus CF (BC + CF), coffee residue compost plus CF (CRC + CF), cattle manure compost plus CF (CMC + CF), and cattle manure compost (CMC) or sewage sludge compost (SSC) alone at a higher application rate. SOM in those samples was physically fractionated into free particulate form (fSOM), free form occluded in aggregates (oSOM), weakly bound form (wSOM), and strongly bound form (sSOM). Analysis of structural components in OAs and SOM fractions using thermally assisted hydrolysis and methylation combined with gas chromatography/mass spectrometry (THM-GC/MS) revealed OA components that have contributed to long-term SOM accumulation in each treatment. The SSC was characterized by higher proportions of short-chain fatty acids (FAs; 50%) and other aliphatic compounds (22%). Correlation analysis suggested that these characteristics may be effective for greater C accumulation in the bulk soil and wSOM fraction. The proportion of lignin-derived phenols, e.g., 3,4-dimethoxybenzaldehyde (Vh) and 1,2-dimethoxy-4-(1,2,3-trimethoxypropyl)benzene, was high in CMC (43%), presumably vital for promoting C accumulations in the oSOM, wSOM, and sSOM fractions in the CMC treatment. The short-chain FAs in CRC and aromatic components in BC are likely important for contributing fSOM accumulation.