Waste Oil Research Articles

Experimental study, simulation and technical–economic feasibility of an interesterification plant for hydrocarbons synthesis by using plastics and frying oil waste

This work presents the experimental assessment of a 20 mL batch reactor’s efficacy in converting plastic and oil residues into biofuels. The reactor, designed for ease of use, is heated using a metallic system. The experiments explore plastic solubilization at various temperatures and residence times, employing a mixture of distilled water and ethylene glycol as the solvent. Initial findings reveal that plastic solubilization requires a temperature of 350 °C with an ethylene glycol mole fraction of 0.35, whereas 250 °C suffices with a mole fraction of 0.58. Additionally, the study includes a process simulation of a plant utilizing a double fluidized bed gasifier and an economic evaluation of the interesterification/pyrolysis plant. Simulation results support project feasibility, estimating a total investment cost of approximately $12.99 million and annual operating expenses of around $17.98 million, with a projected payback period of about 5 years.

One-step preparation of magnet-responsive amphiphilic nanoparticles for efficient oil collection

Waste oil collection is crucial for environmental protection. However, the preparation of magnet-responsive amphiphilic nanoparticles (NPs) for oil emulsification and collection generally involves multiple steps, greatly limiting their widespread applications. Here, magnet-responsive amphiphilic NPs are designed and prepared in a single step via co-precipitation and self-assembly. Upon rapid solvent exchange, shellac, poly(lactic acid) (PLA) and PLA-poly(ethylene glycol) (PLA-PEG) co-precipitate around Fe3O4 NPs, which serve as nuclei for the nucleation and growth of the magnet-responsive amphiphilic NPs. Each Fe3O4@PLA-PEG/shellac NP is consisted of two distinct bulbs, one hydrophobic shellac bulb and the other hydrophilic PLA bulb with PLA-PEG on the surface. The NPs show excellent amphiphilicity and performances in stabilizing oil-in-water and water-in-oil emulsions. By tuning the NP shape, the control of the oil/water interfacial curvature and thus the emulsion type has also been demonstrated. Once the oil phase is emulsified and stabilized by Fe3O4@PLA-PEG/shellac NPs, waste oil could effectively be collected by applying a magnetic field, showing good performances in waste oil removal. The method using magnet-responsive amphiphilic NPs presents a simple and green way for rapid and efficient oil collection and removal. In addition, the developed one-step strategy also provides a facile platform to prepare functional amphiphilic NPs for diverse applications, such as oil collection, drug delivery and bioimaging.

EFFECT OF WASTE ENGINE OIL ON PROXIMATE, PHYTOCHEMICAL, AND ANTIBACTERIAL CONSTITUENTS OF Teffairia Occidentalis (PUMPKIN LEAF)

The improper disposal of waste engine oil effluent onto gutters, open lands, and cultivated farm lands is a common practice in Nigeria, especially among mechanics. These effluents contain substances derived from hydrocarbons that can diminish soil fertility and also influence the properties of plants. This study was consequently undertaken to examine the effects of waste engine oil on the nutritional, phytochemical, and antibacterial constituents of Telfairia occidentalis (Pumpkin leaf). Various levels (0ml, 100ml, 200ml, 300ml, and 400ml) of diesel oil contamination were mixed with 2 kilograms (kg) of soil, with each treatment replicated three times. Plants were watered daily for four months, and after 16 weeks, leaf samples were collected for laboratory analysis. The nutritional composition, phytochemical properties, and antibacterial components of the leaves were examined. The results indicated a significant reduction (P<0.05) in protein (12±0.02), fats (7±0.02), ash (15±0.25), fiber (10±0.03), and carbohydrate (10±0.25) content in the 400ml waste oil treatment compared to the control (0ml) values (protein: 38±0.01, crude fat: 25±0.13, total ash: 45±0.07, crude fiber: 36±0.15, carbohydrate: 42±0.04). Phytochemical analysis demonstrated a noteworthy decrease in alkaloids, saponins, flavonoids, and phenols as waste oil levels increased in the soil, compared to the control (0ml). The antibacterial activity screening revealed that among the various concentrations (80mg/ml, and 20mg/100 ml) of extracts studied, 80g/ 100 ml showed the highest degree of inhibition on all the test organisms. However, there was a notable reduction in inhibition as the level of waste oil pollution increased in the soil, compared to the control...

Prospect of Biodiesel from Sludge Palm Oil in Malaysia

High feedstock costs make biodiesel production impractical and economically unfeasible, particularly as most feedstocks are unknown for performance. Waste oil, such as sludge palm oil (SPO), may be used to produce biodiesel. This study examined the efficiency and prospect of Sludge Palm Oil Biodiesel (SPOB) production from SPO through transesterification. One-step and two-step transesterification methods were performed for SPOB conversion. However, only a two-step method was effective in converting SPO into SPOB. SPO's high free fatty acid (FFA) content necessitated a two-step process to reduce FFAs to less than 4% before SPOB conversion. Step 1 yielded 78% SPOB at 2 hours, 0.03:1 acid catalyst–to–oil, and 8:1 alcohol–to–oil. The optimal SPOB yield for step 2 at 4 hours, 0.01:1 alkaline catalyst–to–oil, and 9:1 alcohol–to–oil was 78%. SPOB components were analyzed using FTIR with SPOB having a 1435.04 cm-1 methyl peak. The diesel engine performance test mixed SPOB with mineral diesel at different concentrations with 30% SPOB blends in mineral diesel offers the lowest fuel consumption (0.1089 ml/s), maximum braking horsepower (24.9266 rpm), and best mechanical efficiency. Density, flash point, and heating value were also tested to identify SPOB's physical characteristics and discussed in detail.

Isolation and identification of hydrocarbon degrading bacteria and fungi from waste engine oil impacted soil, their distribution frequency and hydrocarbon degradation capacity

The isolation and identification of hydrocarbon degrading bacteria and fungi from waste engine oil contaminated soil obtained from Mechanical Village, Uyo, Akwa Ibom State, their distribution frequency and hydrocarbon degradation capacity were investigated using standard method. The results revealed that Bacillus myocoides, Staphylococcus aureus, Listeria murrayi, Actinomycete viscosus, Clostridium sporogenes, Bacillus licheniformis, Corynebacterium ulcerans and Clostridium histolyticum were bacteria identified. Fungi identified were Fusarium oxysporum, Cryptococcus terreus, Penicillium notatum, Aspergillus fumigatus, Rhizopus stolonifer, Rhizopus oryzae and Rhodotorula mulcilaginosa. Their distribution frequency were B. myocoides (27.9 %), S. aureus (8.1 %), L. murrayi (9.9 %), A. viscosus (11.7 %), C. sporogenes (16.2 %), B. licheniformis (7.2%), C. ulcerans (12.6 %) and C. histolyticum (6.3 %) for bacteria. For the fungi, F. oxysporum (15.3 %), C. terreus (4.1%), P. notatum (20.4 %), A. fumigatus (11.2 %), R. stolonifer (10.2 %), R. oryzae (24.5%) and R. mulcilaginosa (14.3%). The efficiency of the microbial isolates to degrade waste engine oil from petrol and diesel driven vehicles as their major source of energy were found to vary among the microorganisms. C. sporogenes degraded waste engine oil from petrol driven vehicle with the highest efficiency (38.09%), whereas S. aureus demonstrated the least efficiency (19.28 %). C. histolyticum utilized waste oil from diesel vehicle with the highest efficiency (35.00%), while C. ulcerans was the least (17.31%). Among the fungi isolates, R. mulcilaginosa showed most degradation potential for spent oil from petrol driven vehicle (34.85 %) whereas C. terreus was the least (20.00 %). A. fumigatus exhibited highest degradation capacity for spent oil from diesel driven vehicle (29.73 %) while R. oryzae demonstrated the least potential (20.76 %). These results implied that microbial consortium could best be used for remediation of hydrocarbon contaminated soil.

Gasification of Liquid Hydrocarbon Waste by the Ultra-Superheated Mixture of Steam and Carbon Dioxide: A Thermodynamic Study

The thermodynamic modeling of waste oil (WO) gasification by a high-temperature gasification agent (GA) composed of an ultra-superheated H2O/CO2 mixture is carried out. The GA is assumed to be obtained by the gaseous detonation of fuel–oxidizer–diluent mixture in a pulsed detonation gun (PDG). N-hexadecane is used as a WO surrogate. Methane or the produced syngas (generally a mixture of H2, CO, CH4, CO2, etc.) is used as fuel for the PDG. Oxygen, air, or oxygen-enriched air are used as oxidizers for the PDG. Low-temperature steam is used as a diluent gas. The gasification process is assumed to proceed in a flow-through gasifier at atmospheric pressure. It is shown that the use of the detonation products of the stoichiometric methane–oxygen and methane–air mixtures theoretically leads to the complete conversion of WO into a syngas consisting exclusively of H2 and CO, or into energy gas with high contents of CH4 and C2-C3 hydrocarbons and an LHV of 36.7 (fuel–oxygen mixture) and 13.6 MJ/kg (fuel–air mixture). The use of the detonation products of the stoichiometric mixture of the produced syngas with oxygen or with oxygen-enriched air also allows theoretically achieving the complete conversion of WO into syngas consisting exclusively of H2 and CO. About 33% of the produced syngas mixed with oxygen can be theoretically used for PDG self-feeding, thus making the gasification technology very attractive and cost-effective. To self-feed the PDG with the mixture of the produced syngas with air, it is necessary to increase the backpressure in the gasifier and/or enrich the air with oxygen. The addition of low-temperature steam to the fuel–oxygen mixture in the PDG allows controlling the H2/CO ratio in the produced syngas from 1.3 to 3.4.

Synergistic Benefits of Combined Application of Manures and Chemical Fertilizers: Enhancing Growth and Yield of Rice and Wheat

The incorporation of compost and manure with chemical fertilizer has become a key concern to sustain soil fertility. Because the nutrients are continuously depleting from the soil and consequently creating a risk to preserving soil health. Aims: This study assesses the response of different doses of cowdung (CD), municipal solid waste compost (MSWC), oil cake (OC), and poultry manure (PM), incorporated with fertilizers on the growth, yield and protein content of BRRI dhan49 rice and BARI Gom-24. Study Design:  RCBD with 8 treatments and 3 replications. Place and Duration of Study: Field experiment and nutrient analysis were carried out at Bangladesh Agricultural University (BAU), Mymensingh. Wheat was grown during the rabi season from October 2018 to March 2019. Again, rice was cultivated during kharif II season from August 2019 to December 2019 on the same field. Then the laboratory analysis was performed till June 2020. Methodology: Eight treatments i.e., T0 Control (no fertilizer), T1 Recommended Fertilizer Dose, T2 (CD + NPK), T3 (MSWC + NPK), T4 (OC + NPK), T5 (PM + N), T6 (MSWC + N), T7: (CD + OC) were accommodated. Data on the growth parameters including grain and straw yields were documented after the harvest of the fully matured crop simultaneously determining the nitrogen (N) and protein content. Results: Adoption of various combinations of compost and manures with fertilizer accorded an increase in yield contributing characters as well as the N and protein content. Integrating MSWC @ 10 t ha-1+N projected the highest grain yield (7.11 t ha-1 in rice; 4.84 t ha-1 in wheat) and straw yield (8.8 t ha-1 in rice; 5.55 t ha-1 in wheat). It also promisingly secured the highest protein content compared to all other treatments. Conclusion: The appliance of MSWC @ 10 t ha-1 with the recommended dose of N may be endorsed for rice and wheat cultivation in the AEZ-9 region and retaining the physicochemical properties of Old Brahmaputra Floodplain soils.

CHARACTERIZATION OF FATTY ACID ETHYL ESTER BIODIESEL (CWO100) PRODUCED FROM COMPOSITE WASTE OILS, ETHANOL AND KOH

There is an urgent need to convert Composite waste oils (CWOs) from domestic and industrial sources using circular system thinking approach due to the growing concern of their socio-economic, environmental and governance effects and impacts of increased human anthropogenic activities. CWO was first pre-treated by sieving, heated to reduce moisture/water concentration and the acid value lowered with the addition of sufficient KOH, then base transesterification reaction with ethanol (1:1), 1% KOH at 700C for 2 h. The physio-chemical and fuel properties of the CWO100 was analyzed using standard analytical methods, and the data statistically using SPSS version 20.0. CWO100 (FAEE) has lowest value of water and sediment, acid value, free fatty acid, carbon residue and sulphur, and the highest values for viscosity, specific gravity, density, colour, flash point, iodine. Most of its parameters are within the ASTM/EN standards except in CWOs that requires pre-treatment. CWO100 is better than petroleum diesel and can be applied in diesel engines, plants with little or no modification as a major alternative now and thereafter.

Role of exogenous hydrogen in methane yield during anaerobic digestion of waste fat, oil, and grease by coupling carbon cloth with exogenous hydrogen

Carbon cloth (CC) coupled with exogenous hydrogen (EH2) was used to promote direct interspecies electron transfer (DIET) during anaerobic digestion of waste fat, oil, and grease (FOG). However, whether the change of EH2 injection pattern would further enhance DIET and FOG conversion for methane production is unknown, and the underlying mechanism is not fully understood. In this study, three EH2 injection pressures (0.2/0.4/0.6 atm) and frequencies (once/every 8 days/every 4 days) were chosen to collaborate with CC for investigating the role of EH2 in methane yield during FOG digestion. The results show that, combined with CC, increased EH2 injection pressure/frequency resulted in gradually enhanced DIET to increase FOG conversion rate (from 69.9% to 96.7%), leading to the highest cumulative methane production (1204.9 mL/gVSadded) 58.9% higher than that of Control. During the digestion, the secretion of extracellular polymeric substances was increased by EH2 to promote bioaggregation and electron transfer between cells for enhanced biological DIET in the digestate. The influence of EH2 on the microbial communities on CC surface was bigger than that in suspended sludge, leading to enhanced syntrophic acetate oxidation-hydrogenotrophic methanogenesis (SAO-HM) for acetate conversion on CC. As the amount of EH2 increased, the acetate conversion by SAO-HM via DIET was improved, which simultaneously promoted the syntrophic metabolisms between acidogens/acetogens and methanogens to achieve more efficient FOG conversion. Together, this work provides new insight into the role of EH2 in the enhancement of DIET and methane yield during FOG digestion.

Protective effects of microbial biosurfactants produced by Bacillus halotolerans and Candida parapsilosis on bleomycin-induced pulmonary fibrosis in mice: Impact of antioxidant, anti-inflammatory and anti-fibrotic properties via TGF-β1/Smad-3 pathway and miRNA-326

Idiopathic pulmonary fibrosis (IPF) is an irreversible disease which considered the most fatal pulmonary fibrosis. Pulmonary toxicity including IPF is the most severe adverse effect of bleomycin, the chemotherapeutic agent. Based on the fact that, exogenous surfactants could induce alveolar stabilization in many lung diseases, the aim of this study was to explore the effects of low cost biosurfactants, surfactin (SUR) and sophorolipids (SLs), against bleomycin-induced pulmonary fibrosis in mice due to their antioxidant, and anti-inflammatory properties. Surfactin and sophorolipids were produced by microbial conversion of frying oil and potato peel wastes using Bacillus halotolerans and Candida parapsilosis respectively. These biosurfactants were identified by FTIR, 1H NMR, and LC-MS/MS spectra. C57BL/6 mice were administered the produced biosurfactants daily at oral dose of 200 mg kg−1 one day after the first bleomycin dose (35 U/kg). We evaluated four study groups: Control, Bleomycin, Bleomycin+SUR, Bleomycin+SLs. After 30 days, lungs from each mouse were sampled for oxidative stress, ELISA, Western blot, histopathological, immunohistochemical analyses. Our results showed that the produced SUR and SLs reduced pulmonary oxidative stress and inflammatory response in the lungs of bleomycin induced mice as they suppressed SOD, CAT, and GST activities also reduced NF-κβ, TNF-α, and CD68 levels. Furthermore, biosurfactants suppressed the expression of TGF-β1, Smad-3, and p-JNK fibrotic signaling pathway in pulmonary tissues. Histologically, SUR and SLs protected against lung ECM deposition caused by bleomycin administration. Biosurfactants produced from microbial sources can inhibit the induced inflammatory and fibrotic responses in bleomycin-induced pulmonary fibrosis.

Advancements in Expanded Clay Manufacturing Using "Clay-Desert Sand-Oil Sludge" Sludge Composite Materials

This study explores the development of resource-saving expanded clay technology utilizing underutilized clay raw materials and oil extraction waste. Traditional expanded clay production is energy-intensive and often employs high-quality clay; however, our research identifies technological modes and parameters for producing expanded clay through plastic molding, incorporating substandard raw materials and oil sludge. This method eliminates the need for costly energy-releasing additives and reduces energy costs associated with drying and firing by 25-30%. The research aims to demonstrate the feasibility of this novel production technique in the Republic of Kazakhstan, considering the local availability of raw materials, energy resources, and regional demand for thermal insulation materials in industrial and civil construction. Our findings suggest that integrating 'Desert Sand-Oil Sludge' into the batch composition can effectively produce granulated porous thermal insulation material, aligning with the region's development strategy and offering significant economic and environmental benefits.
 Highlights:
 
 Resource Utilization: Uses oil waste and substandard clay to produce expanded clay, reducing reliance on high-quality materials.
 Energy Savings: Cuts energy costs for production by 25-30% through innovative processing.
 Regional Benefit: Aligns with Kazakhstan's strategy by utilizing local resources and supporting construction needs.
 
 Keywords: Expanded Clay, Oil Sludge, Desert Sand

Assessment of the Ra-226 and Ra-228 Content in the Bottom Sediments of the Kolva and Usa Rivers (Bolshezemelskaia Tundra of the Nenets Autonomous Region and the Komi Republic)

An assessment was made of the content of natural radionuclides Ra-226 and Ra-228, as well as petroleum products, in the bottom sediments of the Kolva and Usa rivers (Bolshezemelskaia tundra of the Nenets Autonomous Region and the Komi Republic). The values of the specific activities of the studied radionuclides, their isotope ratios, the concentration of petroleum products are obtained, and the correlation dependences of the specific activities of Ra-226 and Ra-228 on the concentration of petroleum products are established. It has been demonstrated that certain sections of the Kolva river are characterized by increased content of Ra-226 in bottom sediments. It was concluded that the likely source of radionuclide entry into bottom sediments is the entry of oil and gas waste into surface waters.

Cleaning of fine-grained lignite by two-stage hydrophobic flocculation using different waste oils

ABSTRACT In this study, the conditions for obtaining clean coal from fine-grained lignite suspensions by two-stage hydrophobic flocculation using different waste oils were investigated. Waste vegetable oil, waste hydraulic oil and waste engine oil were chosen as bridging liquids for hydrophobic flocculation tests. During the studies, sodium silicate was used as the dispersant. Acetone was used at each stage to clean the floc obtained from the agglomeration process. The ash content (%) and combustible recoveries (CR, %) of the floc obtained at the end of each experiment were determined. In addition, contact angle (θ) and calorific values (kcal/kg) were measured and the results were evaluated in detail. At the end of the cleaning stages, low ash clean coal was obtained with a very high combustible recovery. In addition, it was observed that the calorific values increased considerably from 5128 to 5772,5558 to 6304 and 5447 to 5732 using waste vegetable oil, waste hydraulic oil and waste engine oil, respectively.

Chitosan-supported calcium hydroxide hybrid material as new, efficient, and recyclable catalyst for biodiesel production

In this work, a novel supported catalyst was prepared starting from calcium chloride and chitosan flakes using a very mild approach in an aqueous medium without final calcination at high temperatures. The as-prepared catalyst was fully characterized by thermogravimetric analysis (TGA), attenuated total reflectance Fourier transform infrared (ATR-FTIR), and X-ray photoelectron (XPS) spectroscopies, transmission and scanning electron microscopies (TEM, SEM), Energy Dispersive X-ray Spectroscopy (EDS), demonstrating that it consists of calcium hydroxide particles of about 200 nm supported on chitosan micrometric structures. The most crucial parameters in the transesterification process were investigated. A methanol/oil ratio of 6:1, a reaction time of 6 h, and a temperature of 60 °C were found to lead to complete conversion. A reaction on a gram scale using waste oil as a starting material was also tested, and excellent results were achieved. Moreover, the catalyst proved to be very robust, since even after the 10th recycle, the conversion rate remained at around 90 %. Spectroscopic analyses showed minimal leaching of material without modification of chemical composition. The kinetic behavior (activation energy, Ea) of the catalyst was also studied, which resulted in similar outcomes to Ca-based systems present in the literature, but without the need for costly preparations and with superior recycling resistance. An Ea value of 63.25 kJ·mol−1 was found, which agrees with data reported in the literature.

Utilization of Plant Oils for Sustainable Polyurethane Adhesives: A Review.

The utilization of plant oils as a renewable resource for the production of polyurethane adhesives presents a promising way to improve sustainability and reduce environmental impact. This review explores the potential of various vegetable oils, including waste oils, in the synthesis of polyurethanes as an alternative to conventional petroleum-based raw materials. The investigation highlights the environmental challenges associated with conventional polyurethane production and highlights the benefits of switching to bio-renewable oils. By examining the feasibility and potential applications of vegetable oil-based polyurethanes, this study emphasizes the importance of further research and development in this area to realize the full potential of sustainable polyurethane adhesives. Further research and development in this area are key to overcoming the challenges and realizing the full potential of plant-oil-based polyurethanes in various industrial applications.

Repurpose of used frying sunflower oil as an ecofriendly plasticizer for polylactic acid

The development of competitive and sustainable additives for use in semicrystalline polymers is currently an area of growing interest in scientific and engineering areas. However, the feasibility of using waste oils as raw materials to produce effective plasticizers for these polymers has not yet been thoroughly investigated. In this work, the plasticization of polylactic acid (PLA), which is essential to improve its ductility, was studied using different contents of low molecular weight plasticizers: one synthesized from sunflower (Helianthus annuus) oil used in frying (USOP) and the bio-based commercial tributyrin (TB), selected as a control plasticizer. The experimental results revealed changes in the properties of pure PLA matrix that were explained considering the shape and chemical structure of the different plasticizers. Both compounds drastically decreased the glass transition temperature of PLA as well as the elastic modulus and tensile strength, although increase the elongation at break. The greatest plasticizing effect was obtained by adding 15 percent by weight of TB to the biodegradable matrix. However, the synthesized bio-based plasticizer exhibits a desirable low volatility, thus its thermal degradation occurs at higher temperatures in comparison with that of TB. Furthermore, the water vapor permeability of the PLA is not affected when USOP is used as plasticizer, which is a very interesting result for applications in which the material is in contact with food or humid environments.

POTENTIAL OF CATTLE FEED FROM PALM OIL LEAVES AND MIDRIBS USING THE FERMENTATION PROCESS IN WEST KALIMANTAN

Abstract: One of the most crucial phases of cattle farming is the supply of high-quality animal feed, which can enhance productivity and animal health. Animal feed is often a problem in West Kalimantan. However, this area is an oil palm plantation, so it has the potential to produce oil palm waste. This community service activity aims to increase knowledge and practice community skills in oil palm plantations in utilizing palm oil waste in cattle feed. The community service applied a socialization and training methods to make high-quality fermented animal feed using palm oil waste, namely leaves and fronds. Participants in this program included the village chief and the village's livestock owners, a total of 30 people. The farmers benefited from the results of this training and socialization. The villagers can use palm leaves and fronds to make fermented animal feed. This adds insight into how to improve livestock productivity and health. In addition, this activity also has the potential to reduce the amount of palm oil waste generated, in addition to increasing the economic value of the waste. The results of the feed processing technology service activities after socialization and training were carried out, there was an increase in participants' knowledge regarding understanding feed processing, post-test scores from 33% to 80% after the post-test, and post-test scores on feed processing practices from 40% to 80% after the post-test. 

Waste cooking oil based capsules for sustainable self-healing asphalt pavement: Encapsulation, characterization and fatigue-healing performance

Waste cooking oil has surfaced as a hazardous waste that induces severe environmental contamination. Encapsulation technology presents a viable solution to regenerate the waste oil and augment the self-healing ability of asphalt materials. This study characterized capsules synthesized with selected waste oil for self-healing asphalt mixture, and evaluated the self-healing and environmental impact. The wetting ability, capillary, anti-aging, and self-healing performance of three potential healing agents were analyzed, and the optimal healing agent was obtained by evaluating the comprehensive behavior with the radar chart method. Capsules were synthesized using the ionic gelation method, and their thermal stability, chemical structure, mechanical performance, and morphology were characterized. Fatigue-healing performance asphalt mixture with capsules were investigated by indirect tensile fatigue test with intermittent time. Leakage of waste oil core were measure to verify it environmental impact to surroundings. Results showed that all healing agents could restore the aged asphalt, and waste rapeseed oil had superior overall performance with comprehensive fi value of 0.993 in radar chart evaluation. The compression characteristic of the capsules could transform from brittleness to plasticity as the water-to-oil(WO) ratio decreases from 15 to 5. SEM observation implied when the WO ratio varied from 10 to 15, the multi-pore structure of capsules could be appropriately filled. The addition of capsules in the mixture increased the fatigue life extension rate (HDf) of aged mixtures (with intermittent time 0.1 s∼0.8 s) by 10∼30%. Leakage of waste oil from the mixture was inhibited, substantially reducing 38% release of waste oil. This can serve as a means for the sustainable utilization of waste oil, thereby mitigating environmental pollution and negative effects caused by waste oil.

Fat, Oil, and Grease Sewer Waste Management System: A Modeling Platform for Simulating the Formation of FOG Deposits in Sewer Networks

Fat, Oil, and Grease Sewer Waste Management System: A Modeling Platform for Simulating the Formation of FOG Deposits in Sewer Networks

Characteristic and mechanism of pollution by laser cleaning high-value vehicle parts with a complex structure in remanufacturing industry

Remanufacturing high-value vehicle parts is of substantial significance for the circular economy because it provides a second service life and reduces solid waste generation. Laser cleaning is a promising method in the remanufacturing industry owing to its high energy, precision, and efficiency. However, the pollution caused by laser cleaning remains unknown and has rarely been reported, limiting the application of this method. In this study, pollution removal and conversion using a high-energy laser were explored, and environmental life cycle and health risk assessments were conducted. The results showed that high-energy lasers might induce new organic pollutants, such as olefins, alkynes, and aldehydes. During laser cleaning, thermal elastic expansion and shock wave generation were the main mechanisms of rust removal, and evaporation and small-scope boiling were used for waste oil removal. The mean concentration of PM10 was above 7000 μg/m3 in laser rust removal, and the total concentration of volatile organic compounds (VOCs) was the highest in laser oil removal (∼2568 μg/m3). Particulate matter contained high amounts of Fe, Al, and Mn. An environmental life cycle assessment indicated that laser cleaning for stain removal significantly reduced the total environmental impact compared with that of traditional solvent-ultrasonic cleaning (∼40.0%) and sandblasting (∼83.3%). This study provides an environmental protection basis for increasing the use of laser cleaning in the remanufacturing industry.