Thermal Pretreatment Research Articles

Effects of Different Pre-Treatments on Local Pineapple Leaf as a Potential Substrate for the Production of Value-Added Products

Lignocellulosic biomass such as pineapple leaves can be applied as substrates in various biochemical processes such as solid-state fermentation to produce industrially important enzymes or other value-added products. However, recalcitrant nature of the biomass hinders the accessibility of cellulose for enzymatic hydrolysis in yielding high amounts of the intended products. In order to overcome this obstacle, pre-treatment is necessary as to loosen the lignocellulose structure to ease accessibility of enzymes and biodegradability of the biomass. In this study, local pineapple leaves were subjected to different methods of pre-treatments which are thermal pre-treatment by autoclaving, and chemical pre-treatments involving treatments with alkaline solutions (1% and 1.5% (w/v) sodium hydroxide) as well as acid solutions (1% and 1.5% (v/v) hydrochloric acid). Scanning Electron Microscopy was conducted to compare and study the effect of different pre-treatments on morphological changes of raw and pre-treated leaves. The obtained results revealed that the biomass was severely affected by 1.5% (v/v) hydrochloric acid solution as the surface structure was vigorously ruptured and more aggregated cracks were clearly visible in most parts, compared to the surface morphologies observed on raw samples and samples with other pre-treatment methods.

Enhanced volatile fatty acids production in thermal hydrolysis pretreatment with constant pH regulation: Effects evaluation and mechanism elucidation

Enhanced volatile fatty acids production in thermal hydrolysis pretreatment with constant pH regulation: Effects evaluation and mechanism elucidation

Optimizing anoxic/oxic intervals in intermittent aeration for STHP-AD filtrate treatment: Restoring partial nitrification and community dynamics in the SPNAD system

Currently, partial nitrification (PN) processes are commonly used to improve efficiency in high ammonia nitrogen wastewaters. However, initiating and restoring damaged PN performance is crucial for optimizing nitrogen removal efficiency without the use of chemical additives. In this study, a simultaneous partial nitrification and denitrification coupled with anammox (SPNAD) sequencing batch biofilm reactor was constructed to treat anaerobic digestion after sludge thermal hydrolysis pretreatment (STHP-AD) filtrate. The PN performance was successfully recovered through optimizing the operation mode of anoxic/oxic alternation within 120 days. Result showed that Nitrosomonas increased from 0.68 % to 3.43 %, while Nitrospira decreased to 0.06 %. The PN recovery also promoted anammox, with the only anammox bacterium of Candidatus Brocadia, detected in the mixing and biofilm sludge of 1.73 % and 1.41 %, respectively. The autotrophic denitrifying bacteria Thermomonas (increasing from 0.47 % to 23.85 %) and Truepera (rising from 2.31 % to 6.54 %) rapidly accumulated. After adjusting to the anoxic/oxic alternation ratio, the hydraulic retention time was shortened from 50 h to 37.5 h, and the oxic time was reduced to half of the initial operation. The PN recovery and anammox enrichment resulted in improving nitrogen removal approximately 20 %. Eventually, the SPNAD system realizes stable and efficient nitrogen removal with the influent nitrogen loading rate of 0.43 kgN/(m3·d), the ammonium removal efficiency of 94.73 ± 3.27 %, and the nitrogen removal efficiency of 72.98 ± 1.27 %. In this study, a new strategy using intermittent aeration while appropriately extending the oxic time was proposed to restore the system’s ability to treat STHP-AD filtrate after PN disruption.

Mechanistic insights into melanoidins-induced hydrophilicity of thermal hydrolyzed sludge and its impact on dewaterability

Although thermal hydrolysis pretreatment enhances disposal efficiency of sludge, it inevitably leads to melanoidins formation, which will negatively impact the subsequent wastewater treatment processes. However, their effect on the dewaterability of thermal hydrolyzed sludge (THS) remains poorly understood. This study aimed to uncover the underlying mechanisms of how melanoidins affecting dewaterability of THS. Using resin-adsorption method to reduce melanoidins content by 50% led to 21% and 6% decreases in capillary suction time and specific resistance to filtration, respectively, and a 14% increase in sludge cake solid content. Conversely, accumulating melanoidins to 200% worsened THS dewaterability, altering surface morphology and reducing floc stability, which increased the content of bound water by 9%. Additionally, a higher melanoidins level increased the hydrophilic components in extracellular polymeric substances while reducing hydrophobic sites and structures. These findings indicate that melanoidins impair THS dewaterability by altering flocs spatial properties and increasing hydrophilic structures and components.

Electron-Beam Writing of Atomic-Scale Reconstructions at Oxide Interfaces.

The epitaxial growth of complex oxides enables the production of high-quality films, yet substrate choice is restricted to certain symmetry and lattice parameters, thereby limiting the technological applications of epitaxial oxides. In comparison, the development of free-standing oxide membranes gives opportunities to create novel heterostructures by nonepitaxial stacking of membranes, opening new possibilities for materials design. Here, we introduce a method for writing, with atomic precision, ionically bonded crystalline materials across the gap between an oxide membrane and a carrier substrate. The process involves a thermal pretreatment, followed by localized exposure to the raster scan of a scanning transmission electron microscopy (STEM) beam. STEM imaging and electron energy-loss spectroscopy show that we achieve atomically sharp interface reconstructions between a 30-nm-thick SrTiO3 membrane and a niobium-doped SrTiO3(001)-oriented carrier substrate. These findings indicate new strategies for fabricating synthetic heterostructures with novel structural and electronic properties.

Shaping the Physicochemical and Health-Promoting Properties of Carrot Snacks Produced by Microwave-Vacuum Drying with Preliminary Thermal and Enriching Treatment.

This study analyzed the effects of thermal pre-treatments such as convective drying (P-CD), water (BL_W), and microwave blanching (M_BL) and osmotic enrichment pre-treatments with juices from pomegranate (PG), chokeberry (CH), and sea buckthorn (SB) on microwave-vacuum-dried (MVD) carrot properties. Convective drying (CD) and freeze-drying (FD) were used as a comparative method. The dry matter content and water activity of MVD carrots were varied, but in many cases, the values were comparable to those of FD-dried carrots. Pre-enrichment in CH juice significantly reduced the values of the color parameters L*, a*, and b*, regardless of the drying method. The smallest changes were observed in microwave pre-blanching (M_BL). The lowest loss in carotenoid content was observed in CD-dried carrots (14-34 mg/100 g d.m.). Blanching and enrichment in SB juice allowed significant retention of these compounds. As a result of drying carrots, the total phenolic content (TPC) increased. Compared to the raw material, the TPC content in dried carrots increased 3-9 times. Drying using the FD and MVD methods gave a similar effect of increasing the TPC content, including a greater effect after enrichment in CH juice. The highest average antioxidant activity against the DPPH• and ABTS•+ radicals was recorded for FD-dried carrots (6.9 and 30.0 mg Trolox/g d.m.). SB juice contributed to a significant increase in the total vitamin C content, even by 89.1%, compared to raw carrots. Applying osmotic pre-enrichment in PG juice increased the sugar content in dried FD and CD samples by 37.4-49.9%, and in MVD by 21-59%.

Separating Nucleation from Growth Kinetics of Sn Whiskers using Thermal Pretreatment Followed by Mechanical Loading

Separating Nucleation from Growth Kinetics of Sn Whiskers using Thermal Pretreatment Followed by Mechanical Loading

Integrating Process Simulation and Life Cycle Assessment for Enhanced Process Efficiency and Reduced Environmental Impact in Ferromanganese Production

Process simulation was integrated with life cycle assessment to evaluate process efficiency and environmental impact of the production of manganese ferroalloys for various production modes and different ore mineralogies. Utilizing HSC Sim, the model was designed to evaluate the production process with or without a pretreatment step, where results for simulated cases using a four-zone ferromanganese furnace model were exported to openLCA for a complete life cycle assessment. Two main production scenarios were simulated: a closed ferromanganese furnace running on the duplex method and an open furnace running on the discard slag approach. The closed furnace scenario achieved a 17.5% reduction in energy consumption and a 16.2% decrease in direct CO2 emissions with CO-rich off-gas pretreatment. The open furnace scenario showed an 11.2% reduction in energy consumption with thermal solar energy pretreatment but no change in CO2 emissions.

Additive manufacturing of polyamide 12 bulk structures using directed energy deposition with a thulium laser: Effect of process conditions on morphology and mechanical performance

Laser-based directed energy deposition of polymers (DED-LB/P) is a highly flexible additive manufacturing process capable of fabricating three-dimensional structures with a high degree of customization on free-form surfaces. In this article, the manufacturability of polyamide 12 bulk structures using DED-LB/P in combination with a thulium laser operating at a wavelength of 1.94 μm is investigated for the first time. The typical absorption bands at this wavelength eliminate the need for additives such as carbon-based nanoparticles, which would limit the range of applications. The generated structures were analyzed regarding porosity, thermal behavior, and mechanical properties to evaluate the potential of DED-LB/P with a thulium laser. As a consequence of the evaporation of absorbed moisture or ethanol residues resulting from powder preparation, a thermal pretreatment of the polymer powder reduced the porosity of the DED-LB/P structures to 0.9%. Depending on the processing parameters, the crystallinity of the produced structures ranged from 25.6% to 29.9%. For the tensile tests, the required geometries were milled from the DED-LB/P bulk structures. The results show that an ultimate tensile strength of up to 52 MPa, an elongation at break of up to 58%, and Young's modulus of up to 1590 MPa can be achieved. These remarkable mechanical properties are primarily attributed to the complete melting of the powder particles in DED-LB/P and the improved surface quality resulting from the milling process.

Influence of Chemical and Thermal Pre-Treatment on Pyrolysis Product Constituents of Palm Empty Fruit Bunches

Influence of Chemical and Thermal Pre-Treatment on Pyrolysis Product Constituents of Palm Empty Fruit Bunches

EFFECT OF ULTRASOUND ON THE EXTRACTION OF HYDROXYCINNAMIC ACIDS FROM DANDELION ROOTS

Introduction. Ultrasonic extraction is widely used to accelerate the extraction of biologically active substances (BAS). Given the presence of free and bound moisture in medicinal plant raw materials (MPRM), it is rational to assume a positive effect of ultrasound on the MPRM itself in order to increase the yield of BAS. The aim of the work is to study the effect of ultrasonic pre-treatment of dandelion roots on the yield of hydroxycinnamic acids (HCA) from them and to substantiate the feasibility of pre-treatment this MPRM to obtain tinctures. Material and methods. The object of the study was dandelion roots. The mass fraction and composition of HCA were determined by the spectro-photometric method according to the reaction with Arnov's reagent and by high-performance liquid chromatography using standard samples, respec-tively. Results. Preliminary ultrasound exposure of dandelion roots significantly increases the yield of HCA. The maximum content was determined when MPRM with a layer thickness of 2-4 cm and a particle size of 500 μm or less were exposed to ultrasound for 45 min with a frequency of 31 kHz. The highest amount of HCA in tinctures was determined when they were obtained by fourteen-day maceration and subsequent ultrasound extraction for 15 min using 50% ethanol in a volume of 50 ml per 1 g of MPRM with a particle size of 500 μm or less. Defatting, ultrasonic, thermal pre-treatment and their combination enrich dandelion tinctures with HCA; the greatest enrichment of tinctures with this group of BAS was observed with ultrasonic treatment and thermal treatment followed by defatting. Conclusions. The parameters of preliminary ultrasonic pre-treatment and technological parameters for obtaining tinctures of dandelion roots were ex-perimentally determined. It is recommended to use preliminary pre-treatment of raw materials as one of the stages of the technology for obtaining tinctures, ensuring an increase in the yield of HCA.

A Viability Study of Thermal Pre-Treatment for Recycling of Pharmaceutical Blisters

Pharmaceutical packaging is one of the most used packaging types which contains aluminum and plastics. Due to increasing amounts of waste and rising environmental concerns, recycling approaches are being investigated. Since blisters usually contain a balanced amount of plastics and metals, most of the approaches focus on recycling only one material. Therefore, more sustainable recycling approaches which recover both plastic and aluminum fractions are needed. This study investigates the thermal behavior and degradation mechanisms of plastic-rich and aluminum-rich pharmaceutical blisters using various analytical techniques. Structural characterization revealed that plastic-rich blisters have a thicker profile with plastic and aluminum layers, while aluminum-rich blisters consist of plastic layers between aluminum sheets. Thermal degradation analysis showed two main stages for both types: plastic-rich blisters (polyvinyl chloride) exhibited significant weight loss and long-chain hydrocarbon formation between 210 and 285 °C, and aluminum-rich blisters (polyamide/nylon) degraded from 240 to 270 °C. Differential Scanning Calorimetry and Fourier Transform Infrared Spectroscopy analyses confirmed the endothermic behavior of such a transformation. The gas emissions analysis indicated an increased formation of gasses from the thermal treatment of plastic-rich blisters, with the presence of oxygen leading to the formation of carbon dioxide, water, and carbon monoxide. Thermal treatment with 5%O2 in the carrier gas benefited plastic-rich blister treatment, reducing organic waste by up to 80% and minimizing burning risk, leveraging pyrolytic carbon for protection. This method is unsuitable for aluminum-rich blisters, requiring reduced oxygen or temperature to prevent pyrolytic carbon combustion and aluminum oxidation.

Enhancing Iron Ore Grindability through Hybrid Thermal-Mechanical Pretreatment

Grinding is an important process of ore beneficiation that consumes a significant amount of energy. Pretreating ore before grinding has been proposed to improve ore grindability, reduce comminution energy, and enhance downstream operations. This paper investigates hybrid thermal mechanical pretreatment to improve iron ore grinding behavior. Thermal pretreatment was performed using conventional and microwave approaches, while mechanical pretreatment was conducted with a pressure device using a piston die. Results indicate that conventional (heating rate: 10 °C; maximum temperature: 400 °C), microwave (2.45 GHz, 1.7 kW, 60 s), and mechanical (14.86 MPa, zero delay time) pretreatments improved the studied iron ore grindability by 4.6, 19.8, and 15.4%, respectively. Meanwhile, conventional-mechanical and microwave-mechanical pretreatments enhanced the studied iron ore grindability by 19.2% and 22.6%, respectively. These results suggest that stand-alone mechanical pretreatment or microwave pretreatment may be more beneficial in improving the grinding behavior of the studied fine-grain iron ore sample. The results of the mechanical pretreatment obtained in this study may be used in a simulation of the HPGR system for grinding operations of similar iron ore

Optimized thermal pretreatment for lignocellulosic biomass of pigeon pea stalks to augment quality and quantity of biogas production

By applying heat to the feedstock during the thermal treatment of biomass for the production of biogas, the organic material's biodegradability can be greatly increased. Biogas production is a huge research area for alternate energy production technology. Increased biodegradability, improved methane yield, pathogen, and weed seed destruction, and overall process efficiency are all benefits of this type of pretreatment. It is a useful pretreatment technique for maximizing the production of biogas because it can decrease inhibitory compounds, and increase the digestibility of biomass. This work focused on increasing the efficiency of biogas production from lignocellulosic biomass of pigeon pea stalks by a novel thermal pretreatment. The pigeon pea stalk is initially imposed to physical pretreatment (PT) by an automatic hammer mill which is considered as a base for comparing performance. Thermal pretreatment was carried out for one hour, and two hours durations at different temperatures like 100 °C, 125 °C, 150 °C, 175 °C, and 200 °C. Compared to physically pretreated pigeon pea stalks, 200ᴼC thermal pretreated pigeon pea stalks for two hours have produced 88.41 % higher biogas, 16.14 % increase of cellulose, 19.9 % higher volatile solid removal, and 3.94 % lesser lignin. The enhanced chemical characteristics were ensured by analyzing the chemical composition variations through the FTIR, XRD, and SEM images. So, this is recommended for enhanced biogas production.

Calendula Flowers (Calendulae officinalis flos): Methods to Obtain Fractions of Biologically Active Substances

INTRODUCTION. The pharmaceutical industry aims at developing sustainable resource-saving technologies for manufacturing medicines. Approaches to the effective use of herbal drugs include applying technologies yielding compounds with various pharmacological effects in one production cycle. To date, no standardised herbal drug processing technology has been designed to produce calendula flower-based medicinal products with various pharmacological effects. The Member States of the Eurasian Economic Union (EAEU) process calendula flowers by extraction methods yielding one fraction of biologically active substances per cycle (either only flavonoids or only carotenoids).AIM. This article aimed to investigate the possibility of stepwise processing of calendula flowers to obtain biologically active substances with different polarities (carotenoids, flavonoids, and polysaccharides) per cycle.MATERIALS AND METHODS. The authors extracted carotenoids using hexane. The study included additional thermal pretreatment of the herbal drug. Carotenoids and flavonoids were quantified by spectrophotometry, and polysaccharides were quantified by gravimetric analysis. After hexane removal, the dry oily residue was dissolved in oil with mechanical stirring to obtain the oil extract. The study included a three-step processing method that comprised hexane extraction (extraction of carotenoids with a low-polarity organic solvent), extraction with a water–organic solvent system (extraction of flavonoids), and aqueous extraction (precipitation of polysaccharides).RESULTS. The lipophilic extracts obtained by single hexane extraction or by single hexane extraction and heat treatment had the maximum carotenoid content (~4%), which was 10 times the carotenoid content in the extracts obtained using a water– organic solvent system. Oil extracts were prepared from the dry residue left after removing hexane by distillation at its boiling point. The content of biologically active substances in the oil extracts was comparable to that in the intact herbal drug. Water–organic solvent extraction yielded 68.5% more flavonoids from the herbal drug extracted with hexane than from the intact herbal drug. In contrast, aqueous extraction applied to the intact herbal drug yielded 1.7 times the amount of flavonoids obtained by aqueous extraction preceded by hexane extraction. The water-soluble polysaccharide fraction extracted from the intact herbal drug had 10 times the flavonoid content observed in the fraction extracted from the processed herbal drug. Each subsequent processing step decreased the total polysaccharide content and the content of individual polysaccharide fractions and increased their purity. The ratio of polysaccharide fractions remained unchanged across all processing methods tested.CONCLUSIONS. Stepwise processing of calendula flowers ensured that one processing cycle provided three fractions containing increased amounts of carotenoids, flavonoids, and polysaccharides. Relative to the intact herbal drug, there was a 3.3-fold increase in the yield of carotenoids, and the yields of flavonoids and polysaccharides increased by 44.8 and 41.3%, respectively. The resulting product had a higher degree of purity than the products obtained by pretreatment and double hexane extraction or by using the intact herbal drug. The stepwise processing method is advisable for the production of medicines that are enriched with a specific group of biologically active substances or contain smaller amounts of impurities.

Anaerobic Digestion for Textile Waste Treatment and Valorization

AbstractTextile waste is becoming among the most polluting waste in the world, discarded mostly in landfills. Valorizing textile waste via anaerobic digestion (AD) helps conserve resources, reduce environmental impact, and foster a circular economy. Although several reviews have discussed textile waste AD, there is a lack of detailed understanding of the challenges encountered during textile waste AD. Therefore, the goal of this review is to focus on challenges encountered and possible solutions for those challenges for biogas and fertilizer conversion via AD. Potential strategies include chemical, biological, and thermal pretreatments that significantly increase the digestion process. Co‐digestion of natural textile waste, cotton, and wool with carbon and nitrogen‐rich substrates improves AD efficiency by twofold. Moreover, separating polyester from polycotton and textile dye removal via solvent and advanced oxidation processes significantly increases methane yield compared with untreated textile waste. This review can aid in analyzing suitable methods to optimize the biogas production of textile waste via AD.

Effect of thermal pretreatments on the quality attributes and irradiation markers of sesame oil extracted from sesame seeds without and with gamma irradiation

This study comparatively studied the effects of three thermal pretreatment methods, i.e., wet-heat (WT), roasting (RT) and microwave (MT), on the quality attributes and irradiation markers of sesame oil obtained from sesame seeds without and with gamma irradiation. Results showed that gamma irradiation had negligible effect on the quality of sesame seeds and their extracted oils. The effects of thermal pretreatments on irradiated and non-irradiated sesame seeds and their oils were similar, little synergistic effects were observed. The RT-treated oils had more carotenoids, chlorophyll, total phenols, tocopherols, and heterocyclic volatiles content, as well as longer oxidation induction time, but darker color compared with their WT- and MT-treated counterparts. All oil samples had identical FTIR spectra. Eight radiolytic hydrocarbons were identified in the irradiated sesame oils. Thermal pretreatments reduced the content of radiolytic hydrocarbons, but did not significantly change their composition. Our study helps to identify products from irradiated sesame seeds.

Thermal chemical pretreatment of waste-activated sludge for enhanced solubilization and biogas production: a review

ABSTRACT Waste-activated sludge (WAS) generation is increasing due to the increased generation of wastewater owing to industrialization and urbanization. The disposal of WAS is a significant environmental and financial concern that can be offset by stabilization and valorization via anaerobic digestion (AD). However, the biodegradation is limited due to microbial cells and extracellular polymeric substances (EPS). Physical, chemical, biological, and hybrid pretreatments and the addition of accelerant materials for enhancing direct interspecies electron transfer (DIET) are among the strategies to overcome the poor biodegradation of WAS. Alkaline pretreatment disintegrates the floc structure of WAS by increasing the osmotic pressure, while microwave irradiation has thermal and a-thermal effects and increases the availability of organics for biodegradation. Moreover, the combination of alkaline and thermal pretreatments has synergic effects on solubilization, biogas production, and dewaterability. The disintegration of WAS is recognized by alteration in volatile solid (VS) content, sCOD, BOD/sCOD, turbidity, nutrients solubilization, dewaterability, particle size, specific surface area, change functional group, alteration in microorganism community, microorganism abundance, color, moisture content, lag phase, and biogas production. Higher doses of pretreatment increase COD solubilization but not biodegradable COD. Maximum COD solubilization ranged from 2 to 37% in alkaline, 21 to 260% in the microwave (MW), and 28 to 624% in hybrid pretreatments.

Impact of thermal hydrolysis on VFA-based carbon source production from fermentation of sludge and digestate for denitrification: experimentation and upscaling implications

Stricter nutrient discharge limits at wastewater treatment plants (WWTPs) are increasing the demand for external carbon sources for denitrification, especially at cold temperatures. Production of carbon sources at WWTP by fermentation of sewage sludge often results in low yields of soluble carbon and volatile fatty acids (VFA) and high biogas losses, limiting its feasibility for full-scale application. This study investigated the overall impact of thermal hydrolysis pre-treatment (THP) on the production of VFA for denitrification through the fermentation of municipal sludge and digestate. Fermentation products and yields, denitrification efficiency and potential impacts on methane yield in the downstream process after carbon source separation were evaluated. Fermentation of THP substrates resulted in 37–70 % higher soluble chemical oxygen demand (sCOD) concentrations than fermentation of untreated substrates but did not significantly affect VFA yield after fermentation. Nevertheless, THP had a positive impact on the denitrification rates and on the methane yields of the residual solid fraction in all experiments. Among the different carbon sources tested, the one produced from the fermentation of THP-digestate showed an overall better potential as a carbon source than other substrates (e.g. sludge). It obtained a relatively high carbon solubilisation degree (39 %) and higher concentrations of sCOD (19 g sCOD/L) and VFA (9.8 g VFACOD/L), which resulted in a higher denitrification rate (8.77 mg NOx-N/g VSS∙h). After the separation of the carbon source, the solid phase from this sample produced a methane yield of 101 mL CH4/g VS. Furthermore, fermentation of a 50:50 mixture of THP-substrate and raw sludge produced also resulted in a high VFA yield (283 g VFACOD/kg VSin) and denitrification rate of 8.74 mg NOx-N/g VSS∙h, indicating a potential for reduced treatment volumes. Calculations based on a full-scale WWTP (Käppala, Stockholm) demonstrated that the carbon sources produced could replace fossil-based methanol and meet the nitrogen effluent limit (6 mg/L) despite their ammonium content. Fermentation of 50–63 % of the available sludge at Käppala WWTP in 2028 could produce enough carbon source to replace methanol, with only an 8–20 % reduction in methane production, depending on the production process. Additionally, digestate production would be sufficient to generate 81 % of the required carbon source while also increasing methane production by 5 % if a portion of the solid residues were recirculated to the digester.

Innovative waste activated sludge pre-treatment using a raceway pond Reactor: Integration of Low-Temperature and solar radiation

A novel pre-treatment, using a raceway pond reactor (RPR), combining the use of thermal and solar effects, was applied to enhance anaerobic digestion (AD) of waste activated sludge (WAS) from an urban wastewater treatment plant. Thermal pre-treatment at 25, 50, 60 and 70 °C was carried out for 5 h with (under distinct values of UV radiant power) and without solar radiation and varying WAS depth in the RPR (5 or 7 cm). Higher temperatures (60 and 70 °C) and longer treatment times (3 to 5 h) resulted in increased disintegration of bacterial cells. The WAS pre-treatment significantly (p-value ≤ 0.001) boosted soluble chemical oxygen demand (SCOD) levels, achieving a disintegration degree of 19.7 % at 70 °C with solar radiation (7.2 kJUV L-1WAS), which corresponds to a 15-fold increase of SCOD, compared to the baseline at 25 °C without radiation. Moreover, at the highest temperature (70 °C), there was a significant SCOD increase (p-value ≤ 0.05) of approximately 400 mgO2 L-1 in the presence of solar radiation. This synergetic effect between temperature and solar radiation caused cell damage, membrane rupture, and release of cellular content, shifting extracellular polymeric substances from tightly bound to loosely bound and soluble fractions, consequently improving methane production. Methane production increased by 131 % compared to the control (25 °C) under 70 °C and after 7.2 kJUV L-1WAS, indicating a positive impact on WAS hydrolysis. The technology adopted in this work fosters methane production predominantly using renewable solar energy without chemical residues. This is the first report on RPR for WAS pre-treatment, combining mild temperature and solar radiation.