Search

This study aims to convert oily sludge (OS) into oily sludge char (OSC) by pyrolysis and microwave-induced pyrolysis. The operating parameters affecting the production of chars from OS by pyrolysis (temperature (200–800 °C) and residence time (30–150 min)) and microwave-induced pyrolysis (microwave power (200–800 W) and irradiation time (5–25 min)) were investigated. The tools used to identify the physiochemical properties of the best products were Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), and thermogravimetric and derivative thermogravimetric analysis (TGA-DTG). Energy characteristics including higher heating values (HHV), proximate analysis, element composition, and H/C and O/C atomic ratios were explored. The OSC produced by pyrolysis at a temperature of 600 °C and residence time of 90 min (labeled as OSC-Py@600–90) achieved the highest HHV (22.95 MJ/kg), while the OSC produced by microwave at a microwave power of 800 W and irradiation time of 10 min (labeled as OSC-MW@800–10) achieved the highest HHV (28.33 MJ/kg). The BET surface area of OS, OSC-Py@600–90, and OSC-MW@800–10 are OS 29.56 m2/g, 81.33 m2/g, and 238.52 m2/g, respectively. The data of the current study clarified that the OSCs produced from OS by pyrolysis and microwave processes could be used for energy generation. [ABSTRACT FROM AUTHOR]

AbstractOily sludge is generally produced in the process of oil extraction, refining, storage and transportation and disposal of oily wastewater. Is mixed with crude oil, all kinds of refined oil and residual oil and other heavy oil sludge. The main components of heavy oil are saturated fraction, aromatic fraction, colloid and asphaltene which are difficult to treat in oily sludge. In the treatment of oil-containing sludge is usually used solvent extraction method, but due to the high price of extractant, low recycling rate process is a relatively long, complex process, with high treatment costs. Therefore, it is important to find an efficient and cheap extraction solvent. And ionic liquids as inexpensive, environmentally friendly, strengthen the oil-solid separation effect of green solvents, in the auxiliary oil sludge separation on the research has attracted wide attention. In this paper, through molecular dynamics simulation, the diffusion behavior of the four components of heavy oil under different solvents was simulated by using Material Studio software, and the mean square displacement (MSD) was used to describe the diffusion characteristics of the four components of heavy oil under different solvent systems, and the interactions of the four components of heavy oil under different solvents were analyzed in a microscopic point of view. The results showed that the diffusion coefficients of the four components of heavy oil were large and the diffusion rate was fast in the xylene system, while the diffusion coefficients of the four components of heavy oil were small and the diffusion rate was slow in the ionic liquid system. [ABSTRACT FROM AUTHOR]

Dual-shell reactors using hydrothermal flames as internal heat source were proposed for supercritical water gasification (SCWG) and oxidation (SCWO) of oily sludge to achieve fast preheating and avoid corrosion, salt plugging, and overheating. The SCWG and SCWO systems with hydrogen-rich syngas and electricity outputs, respectively, were established and simulated using Aspen Plus 11. Simulation models were validated by comparing with experimental products and temperature profiles. The maximum exergy destruction coefficients of 28.01% and 24.31% appear in the combustion reactor for both the SCWG and SCWO systems, respectively, indicating the indirect preheating method with hydrothermal flame is critical to the energy efficiency. The increase of reaction temperature promotes hydrogen but inhibits methane formation in the SCWG, and more steam but less syngas is output at higher reaction temperatures. Although more steam and electricity outputs are present at higher reaction temperatures for the SCWO, more fuel input is required. Lower exergy efficiencies are obtained at higher reaction temperatures in both the SCWG and SCWO systems for more energy is output as low grade steam. Less fuel input is required for both the SCWG and SCWO systems at higher feed concentrations, and higher exergy efficiencies can be obtained. The net treatment cost for the SCWG and SCWO systems are 119.19 and 215.47 USD/t, respectively, indicating the SCWG is more economically competitive compared with the SCWO. • Reactors with hydrothermal flames were proposed for SCWG and SCWO of oily sludge. • SCWG and SCWO systems with energy output were built and simulated by Aspen Plus. • The maximum exergy destruction appears in the combustion reactor for SCWG and SCWO. • Lower exergy efficiencies appear at higher temperatuers for more steam output. • The SCWG has certain economic superiority compared with the SCWO. [ABSTRACT FROM AUTHOR]

The current situation of co・pyrolysis of oily sludge was summarized, including co・pyrolysis with biomass, coal, household waste, etc ・ By summarizing the influencing factors of co-pyrolysis and the application status of co-pyrolysis residue, it was clarified that the synergistic mechanism of co・ pyrolysis of oily sludge with different additives in the process of co-pyrolysis and the application of co・pyrolysis residue were the key research directions in the future ・ In order to provide a reasonable and feasible path for the development of oily sludge co-pyrolysis technology and the resource utilization of co・ pyrolysis residue. [ABSTRACT FROM AUTHOR]

Oily sludge (OS) has long been regarded as a hazardous waste, and improper disposal may lead to serious environmental concerns and human health risks. Despite various methods having been proposed and applied to the treatment of OS, the oil occurrence states and properties in sludge are rarely characterized, which may directly link to the selection and effectiveness of treatment methods. Here, confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), gas chromatography (GC), and four components (SARA) analysis were utilized to characterize the changes in the oil occurrence states and compositions in OS samples before and after high-speed stirring (HSS) treatment. Our results show a substantial reduction in the oil concentration of OS after HSS treatment (from 32.98% to 1.65%), while SARA analysis reveals a similar oil composition before and after treatment, suggesting the broad applicability of HSS in removing oil and its insignificant selectivity towards various hydrocarbon components. This is further supported by the total petroleum hydrocarbon (TPH) analysis results, which show that the separated oil phase has a hydrocarbon composition similar to that of the original OS sample. The CLSM and fluorescence analysis suggest a homogeneous distribution of oil in the sludge, with relatively light components more concentrated in the pore systems between coarse mineral particles, whereas relatively heavy components tend to coexist with clay minerals. After HSS cleaning, both light and heavy components are removed to varying degrees, but light components are preferentially removed while heavy components tend to be retained in the sludge due to adsorption by clay minerals. This is consistent with TPH analysis, where a significant decrease in n-alkanes with lower carbon numbers (n-C14 to n-C20) was observed in the residual sample. Our findings demonstrate the dynamic response of oil occurrence states and compositions to the OS treatment process and highlight the importance of characterizing these fundamental properties prior to the selection of OS treatment methods. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) is a promising technology for the conversion of waste biomass into an energy-dense coal-like product known as hydrochar. This study evaluated the application of HTC to generate a renewable solid fuel resource from hazardous oily sludge. The influence of process parameters on the energy characteristics of hydrochar was investigated. A design matrix of 20 experimental HTC runs was used as input for response surface methodology (RSM). The central point for this HTC operation was at a temperature of 200°C, with a duration of 75 min and a concentration of 5.5%. The higher heating value (HHV) increased from 18.18 to 28.7 MJ/kg. A linear correlation was derived between yield and HHV. The influence of process parameters on energy densification and energetic retention properties revealed that energy storage properties were enhanced. In total, 66.6%–80% of energy was retained in hydrochar. The enhancement of the fuel characteristics of hydrochar was demonstrated by the elevated fuel ratio of 0.31 obtained at a temperature of 250°C, thereby indicating the improvement brought about by the HTC process. The quantification of energy losses due to convection and radiation yielded 309 and 1,854 kJ/h, respectively. Maximizing the efficiency of internal heat sources is crucial to conserving energy and reducing costs in HTC. Practical Applications: The activities of the oil industry have several impacts on the environment due to the large amounts of oily waste generated. Oily sludge is a prevalent hazardous waste generated in the petroleum industry, and effectively treating it remains a key challenge for the petroleum and petrochemical sectors. Hydrothermal carbonization is an important thermochemical conversion process that can be used as an energy-efficient alternative to enhance the dewaterability of sludge and meanwhile to convert sludge into high-value-added products, such as clean biofuel, organic fertilizers, and precursors of functional materials. Optimizing the process conditions is essential to successfully implement the HTC processing of oily sludge in real field conditions. In this study, waste oily sludge was converted to an energy-rich product, namely, hydrochar. For this, the study investigated the hydrochar characteristics for hydrothermal conditions including a reaction temperature of 175°C–250°C, a reaction time of 30–120 min, and a solid load of 3%–8%. The study also found that the majority of energy loss occurred during the cooling process and therefore suggests that this process might be operated as a continuous process rather than a batch process. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) is emerging as a promising technology for converting waste biomass into a dense coal-like product known as hydrochar. Oily sludge (OS), known for its toxic, carcinogenic, and mutagenic effects, is classified as hazardous waste, posing negative implications for both humans and the ecosystem if improperly disposed. Consequently, the conversion of hazardous oily sludge into safe and renewable products offers significant benefits. To investigate the HTC process further, a design matrix consisting of 20 experimental runs was utilized, integrating results obtained from HTC experiments as input for response surface methodology (RSM). The variables were restricted to a temperature range of 175°C–250°C, a time span of 0.5–2 h, and a solid load range of 3%–8%. Analyzing the data, it was observed that raw sludge initially exhibited a hydrogen-to-carbon (H/C) ratio of 1.33 and an oxygen-to-carbon (O/C) ratio of 0.59. However, following HTC processing, these ratios decreased significantly to 0.18 (at 250°C, 2 h, 3% solid load) and 0.691 (at 250°C, 1 h, 5.5% solid load), respectively. These decreases can be attributed to dehydration and decarboxylation reactions that occurred during the HTC process. The model equation developed using RSM was: carbon content = 66.29 + 6.98A + 0.3515B–2.60C – 0.0412AB + 0.1730AC – 0.0037BC – 1.83A2 + 0.8005B2 – 0.945C2. Carbon densification increased from 1.09 to 1.45 with hydrochar retaining 66.5%–77.65% of the carbon. HTC holds promise as a sustainable technology for carbon and energy recovery. [ABSTRACT FROM AUTHOR]

Pyrolysis is an effective way for the harmless treatment of oily sludge. The composition, physicochemical properties, and pyrolysis of oily sludge were experimentally studied in the present study. The Starink and Coats-Redfern methods were used to analyze the pyrolysis kinetics of oily sludge. Pyrolysis of oily sludge is divided into four stages: water evaporation stage, light component evaporation stage, heavy component pyrolysis stage, and final pyrolysis stage. The light component evaporation and heavy component pyrolysis stages are the main stages of medium-temperature pyrolysis. The pyrolysis characteristic parameters under heating rates of 10, 20, 30, and 40 K/min were obtained, and the effects of heating rates on the pyrolysis characteristics of oily sludge were discussed. The results show that with the increase in heating rate, the temperature range of each stage expands, and the temperature of the pyrolysis peaks also increases, with an average increase of 14.88%. The activation energies of the main pyrolysis stages obtained by the Starink method and Coats-Redfern method are consistent. In the light component evaporation stage, the activation energies obtained by the two methods are 61.93kJ/mol and 68.6kJ/mol, while the activation energies are 294.88kJ/mol and 367kJ/mol in the heavy component pyrolysis stage. The pyrolysis mechanism functions are obtained, and the pyrolysis kinetic equations under 10, 20, 30, and 40 K/min were constructed and validated by comparison with the results of the calculated properties and experimental measurement. This study can provide a better insight into the heat and mass transfer processes of oily sludge in pyrolysis reactors for further development and optimization. [ABSTRACT FROM AUTHOR]

To improve the homogeneity of heating, the magnetic absorbing material Fe3O4 is considered to use in microwave pyrolysis of oily sludge. Therefore, the effect of Fe3O4 on the microwave pyrolysis of oily sludge is investigated based on gas volatile products. Thermogravimetric mass spectrometry result certifies that Fe3O4 will increase the weight-loss ratio from 13.0% to 14.1%. Also, the characteristic peak intensity of CO in gas products decreases from 5.41 × 10−10 A/g to 1.95 × 10−10 A/g, while H2O increases from 3.57 × 10−10 A/g to 7.32 × 10−10 A/g and CO2 increases from 6.87 × 10−10 A/g to 8.92 × 10−10 A/g. This is caused by the esterification of alcohols and esters and the reduction of Fe3O4 by CO. Based on the decrease in activation energy and enthalpy values of Stage II and IV, it infers that Fe3O4 catalyzes the pyrolysis process of oily sludge to some extent. Similarly, gas chromatography-mass spectrometry results show that Fe3O4 can make the types of gas products increase. Especially, the number of molecular species increases from 5 to 46 under 200–300 °C. Finally, a simple molecular dynamics simulation model is conducted, and the results are in agreement with the experimental results. This study shows that Fe3O4 improves the pyrolysis homogeneity and the pyrolysis efficiency also improves. [ABSTRACT FROM AUTHOR]

Biosiirfartants show great potential in resource treatment dur to their degradability environmental compatibilit)*, lw toxicity and even non-toxicity. Th<* advantages and disadvantages of conventional treatment methods were compared, and the technological development of hiosurtactant resource treatment of oily sludge was rcnru-cd, including single/compound treatment, novel biasurfartant treatment, and nanoparticlc/bio file 1 cell treatment. On this has is, the fiiturc development direction of bias urfact ant treatment technology was prospected, in order to provide some help for fiiturc research. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Technology of Water Treatment is the property of Technology of Water Treatment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oily sludge is a complex system that is inevitably generated during the process of oil extracting and processing. It will cause serious environmental pollution and waste of resources if untreated sludge is discharged. In this paper, a composite emulsion cleaner based on modified graphite oxide and surfactants was developed for cleaning oily sludge. First, graphite oxide (GO) was functionally modified with butylamine, and its structures were verified by Fourier transform infrared spectroscopy (FTIR), X-ray electron spectroscopy (XPS), thermogravimetric analysis (TGA), and environmental scanning electron microscopy (SEM). Then, the oil-in-water composite emulsion cleaner was prepared by using butylamine modified graphite oxide and surfactants. The conditions for emulsion preparation and oil sludge cleaning were modelled and optimized by the response surface methodology. The obtained optimal formulations were: surfactant content was 2.17 ‰ with SDS/AEO-3 ratio of 9:1, GO-A4 content was 0.96 ‰, water-oil ratio was 5:5, and the oil removal rate was 97.45 %. The optimal cleaning conditions were: liquid-solid ratio of 3.2:1, cleaning time of 32 min, cleaning temperature of 28.7 °C, and oil removal rate of 99.02 %. The solid sediments were characterized by FTIR and SEM, which proved the feasibility of cleaning oily sludge with the emulsion. [ABSTRACT FROM AUTHOR]

Biological degradation method, as an environmentally friendly, low-carbon, and clean pollution treatment technology, is widely used for the harmless disposal of oily sludge. The biodegradability of oily sludge with stable emulsification system, high oil, and water content is poor. Therefore, it is necessary to pre-treat the oily sludge to improve its biodegradability, including recover the petroleum resources and remove heavy metals and bio-toxic organic matters. This review systematically summarizes five oily sludge treatment methods and their influences on sludge biodegradability, including pyrolysis, chemical hot washing, solvent extraction, chemical oxidation, and hydrothermal. Pyrolysis at temperatures above 750 °C produces high molecular weight polycyclic aromatic hydrocarbons, chemical hot washing and chemical oxidation would cause secondary pollution, solvent extraction method could not be applied due to the high cost and high toxicity of the extractant, and the oil removal of hydrothermal method is inefficient. Additionally, the principles, advantages, and disadvantages of those treatments and the factors affecting microbial degradation were analyzed, which provide the development direction of pretreatment technology to improve the biodegradability of oily sludge. [ABSTRACT FROM AUTHOR]

Introduce the composition and pollution hazards of oily sludge. This article briefly describes the sources and characteristics of three types of oil sludge with high content, including tank bottom sludge, floor sludge, and refinery sludge. This paper mainly analyzes the technological principles of the traditional hot technologies of oily sludge resource treatment, such as pyrolysis, surfactant, reinjection profile control, lotion, etc・, as well as the advantages and limitations of the relevant processes and the application status at home and abroad. Explored two emerging technologies for treating oil sludge, namely microwave radiation and ultrasonic treatment, with the aim of providing reference suggestions for the resource utilization of oily sludge. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sub/supercritical hydrothermal treatment is a promising technology for efficient resource utilization and complete harmlessness of oily sludge, which is significant for promoting the green and sustainable development of the petroleum industry. In this paper, the effects of reaction temperature, reaction pressure, reaction time and oil content on oil recovery and oil quality (composition, desulfurization and denitrification, and heavy metal content) are studied in detail. RESULTS: It was found that the temperature was the most critical parameter, and the optimal process conditions were 350°C, 20 MPa, 60 min and 12 wt% oil content, under which the oil recovery rate could reach 70.46%. The content of N and S in the recovered oil could be as low as 0.87 and 0.536 wt%, and the ratio of H/C was higher than 1.6. CONCLUSION: It was found that reaction temperature had the most significant effect on oil recovery compared with other reaction parameters. Heavy metals are transferred from the oil phase to the water and solid phases, so the content of heavy metals in the oil phase is up to standard. The experiment shows that supercritical water heat treatment of oily sludge is feasible, which makes possible the commercial application of sub/supercritical water thermal oil collection technology. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Thermal analysis of oily sludge (OS) from steel mills was conducted to understand its added value. The effect of additional catalysts (calcined olivine (C-OL), iddingsite (C-ID), xiuyan jade (C-XY), and their nickel carrier on OS pyrolysis performance was also investigated. The physical properties of OS showed a large number of resins and irons. It was found that OS pyrolysis involves water evaporation, light hydrocarbon escape, the crack of resins, asphaltene decomposition, and inorganic mineral decomposition. TG results demonstrated that the prepared catalyst can effectively improve the weight loss, in which the C-OL (Ni) increased by 11.58 wt.%. The kinetic behavior of the three main weight loss zones in the catalytic pyrolysis of OS was subsequently analyzed. The apparent activation energies of the main stages of OS pyrolysis were 61.03, 18.07, and 62.92 kJ/mol, respectively. The addition of C-OL significantly reduced the apparent activation energies by 31.34, 5.74, and 44.46 kJ/mol. The evaluation of the pre-exponential factor revealed that all stages of OS pyrolysis followed a diffusion model, and the reaction path was not changed by the ore catalysts. [ABSTRACT FROM AUTHOR]

A supercritical water gasification strategy was employed to investigate the effects of different conditions on hydrogen-rich gas production from oily sludge, based on the Aspen Plus platform. Meanwhile, the entire process was assessed with a life cycle assessment (LCA) method. The results indicated that the gas yield was decreased by increasing the sludge concentration. The yield of hydrogen-rich gas (H2 and CH4) was improved with increasing temperature. Higher temperatures were more favorable to gas production. Excessive addition of oxidants could reduce the CH4 yield, thereby lowering the energy efficiency of the process. The LCA analysis found that, in comparison to the stages of raw material transportation, heat recovery, and wastewater treatment, the effect of more CO2 produced in cooling and separation stage on global warming potential (GWP) was more obvious. The corresponding process can be improved to mitigate the environmental effect of the whole gasification. [ABSTRACT FROM AUTHOR]

Oily sludge is a hazardous solid waste, hazardous ingredients (hazardous elements and heavy metals) in pyrolysis products have the potential for secondary pollution. The distribution of hazardous elements (N/S/Cl) during the pyrolysis of oily sludge was determined at different pyrolysis temperatures (350–750°C), and the potential ecological risk of heavy metals (Zn/Cu/Cd/Cr/Pb) in the solid residue was evaluated. The results showed that N-pollutants in oily sludge were mainly distributed at higher pyrolysis temperatures (550°C), S and Cl-pollutants were mainly distributed at 450°C. The leaching concentration of Zn metal in oily sludge was 119.73 mg/L, which has exceeded the concentration limit (100 mg/L) stipulated by GB 16,889–2008. The pyrolysis treatment could reduce the leaching rate of Zn metal to 18.39 mg/L Moreover, the risk assessment code (RAC) values for Zn showed a very high risk environmental risk level. Pyrolysis treatment could reduce the RAC value of Zn and change the environmental risk level of Zn to low risk. The results of this study provide a theoretical basis for the pyrolysis treatment of oily sludge and the control of harmful ingredients. [ABSTRACT FROM AUTHOR]

Thermal treatment has significant advantages in resource recovery for oily sludge (OS). However, the instability of heavy metals (HMs) within the residue poses a considerable risk of secondary pollution. This study explored the migration and transformation of HMs from OS under varying conditions (i.e., temperature, constant-temperature duration time, and different ratios of O2 and CO2). The elevation of the pyrolysis temperature augmented the decomposition of organic matter and total petroleum hydrocarbons (TPHs). However, the increased temperature also diminished the stabilization of HMs, and facilitating the HM’s transfer to oil and gas, particularly for HMs (i.e., As and Pb) with low boiling points. The constant-temperature duration time exhibited a weak impact on HM transformation, but the internal heating mechanism of microwave pyrolysis promoted the stabilization of HMs through vitrification. The existing O2 with oxidizing properties facilitated the oxidation of organic matter and TPHs to CO2 and H2O, which also promoted the transformation of HMs into oxidized states for stabilization. Comparatively, CO2 promoted the thermal cracking and disrupted the stability of HMs to a certain extent. Above all, this work revealed the migration and transformation of HMs in OS varied with the thermochemical methods and possessed an important significance for the immobilization and stabilization of HMs.

Oily sludge (OS) has long been regarded as a hazardous waste, and improper disposal may lead to serious environmental concerns and human health risks. Despite various methods having been proposed and applied to the treatment of OS, the oil occurrence states and properties in sludge are rarely characterized, which may directly link to the selection and effectiveness of treatment methods. Here, confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), gas chromatography (GC), and four components (SARA) analysis were utilized to characterize the changes in the oil occurrence states and compositions in OS samples before and after high-speed stirring (HSS) treatment. Our results show a substantial reduction in the oil concentration of OS after HSS treatment (from 32.98% to 1.65%), while SARA analysis reveals a similar oil composition before and after treatment, suggesting the broad applicability of HSS in removing oil and its insignificant selectivity towards various hydrocarbon components. This is further supported by the total petroleum hydrocarbon (TPH) analysis results, which show that the separated oil phase has a hydrocarbon composition similar to that of the original OS sample. The CLSM and fluorescence analysis suggest a homogeneous distribution of oil in the sludge, with relatively light components more concentrated in the pore systems between coarse mineral particles, whereas relatively heavy components tend to coexist with clay minerals. After HSS cleaning, both light and heavy components are removed to varying degrees, but light components are preferentially removed while heavy components tend to be retained in the sludge due to adsorption by clay minerals. This is consistent with TPH analysis, where a significant decrease in n-alkanes with lower carbon numbers (n-C14 to n-C20) was observed in the residual sample. Our findings demonstrate the dynamic response of oil occurrence states and compositions to the OS treatment process and highlight the importance of characterizing these fundamental properties prior to the selection of OS treatment methods.

In the petroleum sector, the generation of oily sludge is an unavoidable byproduct, necessitating the development of efficient treatment strategies for both economic gain and the mitigation of negative environmental impacts. The intricate composition of oily sludge poses a formidable challenge, as existing treatment methodologies frequently fall short of achieving baseline disposal criteria. The processes of demulsification and dehydration are integral to diminishing the oil content and reclaiming valuable crude oil, thereby playing a critical role in the management of oily sludge. Among the myriad of treatment solutions, ultrasonic technology has emerged as a particularly effective physical method, celebrated for its diverse applications and lack of resultant secondary pollution. This comprehensive review delves into the underlying mechanisms and recent progress in the ultrasonic treatment of oily sludge, with a specific focus on its industrial implementations within China. Both isolated ultrasonic treatment and its combination with other technological approaches have proven successful in addressing oily sludge challenges. The adoption of industrial-scale systems that amalgamate ultrasound with multi-technological processes has shown marked enhancements in treatment efficacy. The fusion of ultrasonic technology with other cutting-edge methods holds considerable potential across a spectrum of applications. To fulfill the goals of resource recovery, reduction, and neutralization in oily sludge management, the industrial adoption and adept application of a variety of treatment technologies are imperative. [ABSTRACT FROM AUTHOR]

Oily sludge-derived activated carbon was prepared using the potassium hydroxide (KOH) activation method using oily sludge as a raw material, and one-factor experiments determined the best conditions for preparing activated carbon. The activated carbon's morphological structure and surface chemical properties were analyzed by scanning different characterization tools, and the adsorption behavior of tetracycline hydrochloride was investigated. The results showed that the optimum conditions for preparing oily sludge-derived activated carbon were an activation temperature of 400 °C, activation time of 30 min, activator concentration of 1 mol/L, and impregnation ratio of 2 mL/g. After activation, the activated carbon had more pores and a more orderly crystal structure arrangement, the specific surface area was 2.07 times higher than that before activation, and the surface was rich in functional groups such as -HO, -C-O, -C=C, and -C-H, which increased the active sites of activated carbon. Physicochemical effects dominated the adsorption process. It belonged to the spontaneous heat absorption process under the quasi-secondary kinetic and Langmuir isothermal models. The maximum monolayer adsorption capacity of KOH-activated carbon was 205.1 mg·g−1. [ABSTRACT FROM AUTHOR]

ObjectiveThe aim is to investigate the effect of electrogenic microorganisms on the electricity generation and perforinances of sediment microbial fuel cell(SMFC) battery system using oily sludge as anode sludge by changing the types and distribution patterns of electricity-producing microorganisms. Methods The output voltage, power density and apparent internal resistance were collected. The oil removal rate was measured, and the electricity generation and degradation properties of SMFC and SMFC were compared, and the effects of different strains on the properties of SMFC were investigated. ResultsIn the single bacteria SMFC, Citrobacter Frei SMFC had better electricity generation and degradation performances than the other five single bacteria SMFC. The electricity generation and degradation performance of mixed bacteria-SMFC were significantly improved comparing with that of single bacteria-SMFC, and Bacillus cereus+Bacillus palpis intermediate-SMFC had the best electricity generation and degradation performance, and the output voltage could reach 515.30 mV. The distribution of the bacteria around the anode material and in the anode bottom mud could degrade the organic matter in the oily sludge, but the distribution of the bacteria in the anode material is more conducive to the performance of SMFC's electricity generation and degradation. Conclusion Mixed bacteria could significantly improve the electricity generation and degradation performance of SMFC when comparing with single bacteria, and the distribution of bacteria on the anode material is more beneficial to the electricity generation and degradation performance of SMFC. [ABSTRACT FROM AUTHOR]

Copyright of Special Oil & Gas Reservoirs is the property of Special Oil & Gas Reservoirs Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The surface-active ILs [C16mim]Cl synthesized by combining imidazole group (C4H6N2) and 1-chlorohexadecane (C16H33Cl) was used as surfactant to prepare ILs microemulsions for sludge treatment. Meanwhile, the treatment conditions were optimized and the optimal conditions were obtained. Due to the strong interaction between ILs and asphaltenes as well as the solubilization of microemulsions, the residual oil rate of oily sludge decreased to 1.33%. The characterization of oily sludge was performed by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR) and contact angle measurement. Results showed that [C16mim]Cl ILs microemulsions treatment could effectively promoted the desorption of asphaltenes from the surface of sludge solids, which provided a clear understanding of the mechanism for ILs microemulsions-enhanced oily sludge recovery. Oil in Water (O/W) microemulsions prepared using ionic liquids [C16mim]Cl as surfactants were used to the treatment of oily sludge with high removal oil rate (97.97%) and low residual oil rate (1.33%). Based on the strong interaction between [C16mim]Cl and asphaltenes as well as the solubilization effect of microemulsions, the use of ionic liquids microemulsions improves the effect of sludge treatment and realizes the effective recovery of crude oil, which has potential applications in the field of energy recovery and environmental protection. [ABSTRACT FROM AUTHOR]

Treatment of an oil-rich sludge from an oil field in southern coastal areas of Iran with an initial total petroleum hydrocarbon (TPH) content of 38,000 mg/kg through composting technology was evaluated, and the effects of re-inoculation using halophile bacteria, mixing ratio, and surfactant application on TPH removal were studied. Results indicated that biosurfactant addition and re-inoculation enhanced the process efficiency, and a TPH removal of 81.7% was observed in selected conditions. Furthermore, mixing ratios of oily sludge and matured compost were critical factors in improving TPH removal. The highest removal rate of 0.91% was seen in the oily sludge/finished compost ratio of 0.5. Pseudo-first-order kinetic model was better fitted with experimental results, and a reaction rate constant of 0.245 week−1 was calculated. Also, the final product qualified the standards of heavy metal content based on the US environmental protection agency recommendation. According to the results obtained, it can be said that composting technology supported by inoculation with halophile bacterial consortium and biosurfactant addition and re-inoculation can be effective in treating oily wastes containing various hydrocarbons. Considering the obtained results, it can be declared that composting can lead to promising results in treating oily wastes containing a variety of hydrocarbons. [ABSTRACT FROM AUTHOR]

Biotreatment of oily sludge and the involved microbial communities, particularly in saline environments, have been rarely investigated. We enriched a halophilic bacterial consortium (OS-100) from petroleum refining oily sludge, which degraded almost 86% of the aliphatic hydrocarbon (C10-C30) fraction of the oily sludge within 7 days in the presence of 100 g/L NaCl. Two halophilic hydrocarbon-degrading bacteria related to the genera Chromohalobacter and Halomonas were isolated from the OS-100 consortium. Hydrocarbon degradation by the OS-100 consortium was relatively higher compared to the isolated bacteria, indicating potential synergistic interactions among the OS-100 community members. Exclusion of FeCl2, MgCl2, CaCl2, trace elements, and vitamins from the culture medium did not significantly affect the hydrocarbon degradation efficiency of the OS-100 consortium. To the contrary, hydrocarbon biodegradation dropped from 94.1 to 54.4% and 5% when the OS-100 consortium was deprived from phosphate and nitrogen sources in the culture medium, respectively. Quantitative PCR revealed that alkB gene expression increased up to the 3rd day of incubation with 11.277-fold, consistent with the observed increments in hydrocarbon degradation. Illumina-MiSeq sequencing of 16 S rRNA gene fragments revealed that the OS-100 consortium was mainly composed of the genera Halomonas, Idiomarina, Alcanivorax and Chromohalobacter. This community structure changed depending on the culturing conditions. However, remarkable changes in the community structure were not always associated with remarkable shifts in the hydrocarbonoclastic activity and vice versa. The results show that probably synergistic interactions between community members and different subpopulations of the OS-100 consortium contributed to salinity tolerance and hydrocarbon degradation. Key points: • A halophilic bacterial consortium efficiently degrades oily sludge hydrocarbons. • Nitrogen starvation and high salinity have the greatest impact on hydrocarbon loss. • Change in the consortium structure is not a prerequisite to shift biodegradation. [ABSTRACT FROM AUTHOR]

Because of the requirements for accelerating the construction of a green, low-carbon, and recycling economy development system, the petrochemical industry has been paying attention to green and low-carbon transformations and innovations. Oily sludge is a type of bulk hazardous solid waste from various sources that significantly harms the environment. Chemical heat washing of oily sludge represents a large proportion of the treatment technology for oily sludge, which can be used individually and has many applications in joint treatment with other processes. However, research on the formulation of cleaning agents for this process has mainly focused on the surfactant at this stage, and many studies have demonstrated the secondary pollution of surfactant; thus, research on reducing or replacing surfactants as cleaning agents has been conducted. This review highlights the research progress of chemical heat washing of oily sludge according to the classification of cleaning agents and describes the reasons for the stabilization of currently recognized oily sludge, the chemical heat washing process, and the mechanism of oil–soil separation. Finally, the research direction for new emulsions as new cleaning agents to replace surfactants is set out. [ABSTRACT FROM AUTHOR]

There are many oily sludge treatment technologies with great development prospects, and due to the lack of an objective and scientific technology evaluation system, there have been different opinions and views on the selection of technologies. To address this issue, this paper establishes a multicriteria decision system based on hierarchical analysis and gray decisionmaking, discusses the weights of oily sludge treatment technologies in terms of economic benefits, technology, environment and social indicators, and categorizes the relevant impact indicators into target level, criterion level and program level, etc. So as to analyze them qualitatively and quantitatively. The results show that in the hierarchical analysis decision system, the order of influence of the weight of each indicator on the research objectives is as follows: technical and environmental impact indicators occupy an absolute advantage for the treatment and disposal of oily sludge, with a weight of 0.5886 for environmental indicators and 0.2074 for technical indicators, whose main impact indicators include the resourceization of oily sludge with a weight of 0.6104 and the pollution degree of soil with a weight of 0.5115. Because X2 shows a high correlation in the evaluation model, the preferred oily sludge and blast furnace slag catalytic pyrolysis treatment, a comprehensive evaluation of oily sludge treatment technologies will help researchers to have a good understanding of the recent developments and future research directions. [ABSTRACT FROM AUTHOR]

Oil sludge is the most important waste of the oil industry, which is known as a complex organic substance due to the presence of petroleum hydrocarbons, water, solids and heavy metals, which is considered a part of special and dangerous waste. Oil sludge recovery technologies include centrifuge, use of surfactant, electrical method, pyrolysis, ultrasound, use of supercritical fluids, etc. Petroleum sludge was placed in a hydrothermal oxidation reactor along with KOH catalyst and deionized water, so that the oxidation process takes place in a supercritical water environment. Three factors, temperature with a range of 320-380 °C, reaction time with a range of 30- 600 seconds and weight ratio of catalyst to sludge from 0 to 0.05 were considered as reaction variables and COD of water remaining from oxidation was considered as the test response. Variance analysis of output results from the response surface method has been done. According to the results, COD removal efficiency ranges from 70.3 to 92.2 percent. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oily sludge is a potentially toxic waste produced in large quantities by the oil and gas industry and the determination of metal concentrations in complex oily samples still presents an analytical challenge. Consequently, the development of suitable sample preparation procedures is required to allow the monitoring of potentially toxic elements in this type of waste. This paper describes a method for the determination of Cd, Co, Cu, Ni, V and Zn in oily sludges by inductively coupled plasma-mass spectrometry (ICP-MS) using a simple and eco-friendly sample preparation procedure based on ultrasound-assisted extraction (UAE). The UAE was performed using 10.5 mol L−1 of nitric acid as the extraction solution, applying 45 min of extraction in an ultrasonic bath at a temperature of 60 ± 5℃. The limits of detection (LOD) and quantification (LOQ) ranged from 0.1 to 0.5 mg kg−1 and from 0.3 to 1.7 mg kg−1, respectively. The accuracy was evaluated through the comparison of results with acid digestion and the paired t-test indicated no difference between the results (n = 6,95% of confidence level). In addition, regression analysis indicated R > 0.999 and differences of < 14.1% from the optimal slope of 1.0, expressing a good correlation between the results obtained applying UAE and acid digestion. The method precision (RSD) was better than 21.0%, which can be considered adequate for the analysis of complex sample matrices. The method was applied to determine the analytes in seven oily sludges from different oil storage tanks and all results were in the mg kg−1 range. The proposed method was evaluated on the Eco-Scale and the score obtained was 84, indicating excellent greenness. Thus, the proposed method is simple, fast, eco-friendly and efficient, and offers good potential for the extraction and determination of potentially toxic metals in oily sludges. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oily sludge (OS), a hazardous waste that generated in the process of petroleum exploration, utilized as raw material in this study for preparation of high value-added glass-ceramics. The effect of CaF 2 addition and temperature on the melting behavior, crystallization mechanism, physical-chemical properties and heavy metals leaching of glass-ceramics was highlighted. The results indicated that the obtained parent glass demonstrated completely amorphous structure at 1200 °C when CaF 2 content was 4 wt%. The addition of CaF 2 improved crystallinity of glass-ceramics, which further improved the glass-ceramics properties. Comparing the properties of OC-1200-830 with OCF4-1030, it was observed that the density increased from 2.27 g/cm3 to 2.60 g/cm3, compressive strength increased from 56.43 MPa to 122.00 MPa, bending strength increased from 6.16 MPa to 11.41 MPa, acid resistance increased from 92.8% to 96.8%, alkali resistance increased from 94.6% to 98.2%, and water absorption reduced from 0.19% to 0.12%. The leaching concentrations of heavy metals in the glass-ceramics were below than the thresholds required in GB 5058.3–2007, China. The theoretical energy consumption of glass-ceramics melted at 1200 °C was 30.84%–41.37% lower than that melted at 1500 °C, which demonstrated that the glass-ceramics prepared in this study have cost advantages. [ABSTRACT FROM AUTHOR]

Oily sludge generated by the petroleum industry is not only an environmental hazard, but since it contains crude oil too, it is a valuable resource as well. This study demonstrates a methodology for the valorization of the oily sludge that allows the recovery of oil fractions by the action of microbes producing surface-active metabolites. Two bacterial isolates were used in the study that were producing different biosurfactants, identified via FTIR analysis as well as through genomic mapping of the biosurfactant pathways using RAST, ANTISMASH 7.0, STRING databases. Serratia spp. AKBS12, produced a mono-rhamnolipid, while Acinetobacter spp. AKBS16, produced emulsan. Although recovery efficiency of both biosurfactants was similar, the recovery profile with respect to the class of hydrocarbons differed. The rhamnolipid produced by Serratia spp. AKBS12 extracted mono-chained paraffins and linear alkanes, while emulsan, produced by Acinetobacter spp. AKBS16 could extract heavier paraffins. The extraction procedure is simple and involves mixing the biosurfactant with oily sludge at a temperature of 30 °C with an incubation of 9 days. Sulphuric acid precipitation releases the oil trapped in the oily sludge. The study is the first step in developing user-friendly, innovative technologies that can be linked to the concept of a circular economy. [ABSTRACT FROM AUTHOR]

Subcritical water upgrading has received a great deal of attention because of its high efficiency and environmental protection technology features, but its high temperature and high‐pressure reaction conditions have limited its further development. This article investigates the hydrothermal upgrading recovered oil from oily sludge at 350°C and for a residence time of 60 min recovered oil. The effects of the type and concentration of various additives sodium hydroxide (NaOH), sodium bicarbonate (NaHCO3) and formic acid (CH3COOH) on the yield and quality of recovered oil were analyzed and discussed. The addition of 2 wt % NaOH increases the recovered oil yield to 78.6%, due to the demulsification effect of alkaline additives. Meanwhile, the CH3COOH effectively increased the H/C ratio of the recovered oil to 1.69, which can be attributed to the hydrogenation of large molecules in the sludge with hydrogen generated from the added CH3COOH. The effect characteristics and mechanisms of adding additives on the increase in the recovered oil yield and quality of oil‐bearing sludge in a sub‐critical hydrothermal environment were revealed. Subcritical water upgrading technology provides a new technological route for resource recovery of oily sludge with mild reaction conditions and high efficiency and simplicity. [ABSTRACT FROM AUTHOR]

This research aimed to purify the environment of undesired substances by converting oily sludge (OS) micro-char fuel generation by microwave. The North Refineries Company (NRC) Baiji was the source of the OS sample utilized in this study. Micro-char manufacture, which has improved solid carbon characteristics, uses various microwave power and irradiation times. The parameters conditions at a range of power: feed of 5 g, 10 min of irradiation time, and microwave power ranges of 200, 400, and 600 W, respectively, under a nitrogen pressure of 3 L/min. While at the range of irradiation time: the feed was 5 g, microwave power was fixed at 600 W (the best microwave power discovered), and the range of irradiation duration was 5, 10, and 15 min. The ideal circumstances were (5 g, 600 W, and 15 min, under N2 pressure). The fuel ratio was increased from 0.70 to 0.97 OS with a 38.57% rise in the percentage of micro-char at 600 W and 15 min of irradiation time, while the HHV was increased from 9.40 to 17.22 MJ/kg at a rate of 83.20% as finding micro-char had improved as a solid carbon fuel. In general, micro-char has a fuel ratio and a higher HHV, making it suitable for solid carbon fuel in the oil industry. [ABSTRACT FROM AUTHOR]

Oily sludge is a kind of harmful solid waste produced by the petroleum industry. It is the key point of research to understand the mechanism of gas product changes during the pyrolysis process. This study combined density functional theory (DFT) calculation with a pyrolysis experiment to explore the changes in pyrolytic gas products from oily sludge. The results of thermogravimetric–mass spectrometry (TG–MS) and gas chromatography–mass spectrometry (GC–MS) showed that the gas products below 400°C were dominated by long‐chain hydrocarbons, but with the increase of the treatment temperature, the long‐chain hydrocarbons will decrease. The results of kinetics and thermodynamics showed that there were five stages of pyrolysis of oily sludge, and the values of E, ΔH, and ΔG were increased with the increase of pyrolysis temperature. The DFT calculation revealed that there were delocalized π‐electrons at the fracture‐prone sites, and the electrons on the functional groups of the molecule were more easily excited. The results can provide ideas for the pyrolysis mechanism of oily sludge and theoretical support for the optimization of the pyrolysis process. [ABSTRACT FROM AUTHOR]

The microbial conversion of alkanes to methane in hydrocarbon-contaminated environments is an intrinsic bioremediation strategy under anoxic conditions. However, the mechanism of microbial methanogenic alkane degradation is currently unclear. Under ten years of continuous efforts, we obtained a methanogenic n-alkane-degrading (C15–C20) enrichment culture that exhibited sustained improvements in the kinetic properties of methane production. The integrated metagenomic and metatranscriptomic analyses revealed that n-alkanes were mainly attacked by members of Desulfosarcinaceae, Firmicutes, and Synergistetes using the fumarate addition strategy, and were then further degraded in a common effort by Tepidiphilus members. Meanwhile, the abundant members of Anaerolineaceae were mainly responsible for cell debris recycling. However, according to the metatranscriptomic analyses, methane was predicted to be produced mainly via H2-dependent methylotrophic methanogenesis, primarily from necromass-derived trimethylamine mediated by Methanomethyliaceae within the candidate phylum Verstraetearchaeota. These findings reveal that H2-dependent methylotrophic methanogens, as well as methylotrophic methanogens, may play important ecological roles in the carbon cycle of hydrocarbon enriched subsurface ecosystems.

How to realize the harmless treatment and resource recovery of oily sludge is a major challenge in the field of petroleum production. Pyrolysis, as a method of thermochemical decomposition of organic matter in an anoxic environment, has great application potential in the harmless disposal and resource utilization of the oily sludge. Pyrolysis of oily sludge has become an important concern in the field of oil exploitation, refining and environmental protection, which has attracted intensive studies in recent years. In this paper, the latest achievements of the pyrolysis and process pollution control technology of oily sludge were reviewed. Guided by the new thermochemical technology of harmless disposal and recycling of the oily sludge, this paper comprehensively summarized and analyzed the recycling of oily sludge pyrolysis and process pollution control, aiming to reveal the transformation process and mechanism of oily sludge components conversion in the pyrolysis process, as well as the generation, transformation and migration routes of nitrogen and sulfur pollutants and their corresponding mechanisms. The design principles of catalysts and the optimization of reaction processes during catalytic pyrolysis and co-pyrolysis, the formation process and influencing factors of small organic compounds containing sulfur and nitrogen, and the migration and transformation of heavy metal elements were investigated. The future application prospect and development trend of this technology were prospected.

Accurate analysis of the main chemical components of oil-bearing sludge is an important prerequisite for effective soil remediation and resource reuse. However, precise analysis of the extract components is difficult to achieve because of the mutual interference of saturates, aromatics, and resins, collectively called SAR, and asphaltene that are introduced during chloroform extraction. In this study, SAR was efficiently extracted using n-heptane, while asphaltene components were retained in soil because of their insolubility in n-heptane. The maximum yield of SAR extraction was 27.0%, indicating an increase of 1.75% compared to chloroform extraction. The extracted SAR components were separated by chromatography and the main structural units and components were analyzed. The results show that saturates, aromatics, and resins have a single component, a high content of major components, and contain fewer impurities using n-heptane extraction. Moreover, the solubility of asphaltene was inhibited during the effective extraction of SAR components with n-heptane and did not influence the subsequent analysis of SAR component. Efficient SAR extraction, accurate SAR component analysis, and high efficiency asphaltene separation was achieved using n-heptane-extraction-assisted pyrolysis. This provides a new method for the component analysis of oily sludge and promotes its efficient separation.

The aim of this study is to find a solution to the challenging problem of disposing oily sludge (OS). Three different types of modifiers, namely, sodium hydroxide (NaOH), sodium dodecylbenzene sulfonate (SDBS), and polyoxyethylene polyoxypropylene polyether (AE) were employed for the simple modification of OS. The influence of modified OS on slurry ability and combustion performance were investigated. The results showed that OS modified by NaOH and SDBS can increase the concentration of coal OS slurry. However, the influence of AE modification on slurry concentration is intricate. In terms of combustion performance, the change in activation energy results in NaOH and SDBS modifications decrease T i and T h of coal OS slurry, while AE modification increases T i and T h of coal OS slurry.

Oily sludge contains a large number of hydrocarbons, heavy metals, and other toxic and harmful substances, which not only pose a significant threat to human health but also severely impact the stability and sustainability of the ecological environment. Therefore, the development of a clean and efficient production process is urgently needed. The ozonation technology is a promising treatment method with high efficiency and no secondary pollution. In this study, ozonation technology was used to degrade the pollutants in the oily sludge, and the impact of different influencing factors on the treatment effect was discussed, and the operational parameters were optimized. Additionally, we investigated the mechanism of ozonation for oily sludge to provide a basis for a deeper understanding. The results demonstrated that after treatment, the total petroleum hydrocarbon content in the oily sludge was significantly reduced, and the residual oil rate decreased to 1.04 %, indicating the enormous potential of ozonation technology for oily sludge treatment. [ABSTRACT FROM AUTHOR]

Objective The aim of this study is to improve the understanding upon the role of individual chemical on the production of oily sludge and provide a reference for the reduction and control of oily sludge in oil and gas field. Methods The study was carried out to preliminarily identify the contribution rate of wastewater treatment chemicals in sludge and their production pattern. Furthermore, sludge production rates in 4 typical stations of Xinjiang Oilfield were estimated theoretically, and the dosages of wastewater treatment chemicals in Station A were optimized. Results The study showed that wastewater treatment chemicals would produce a certain amount of sludge, of which the contribution rates of desiliconizing agent (47.95%) and water purifying agent (PAC) (20.00%-31.00%) were far greater than the contribution rate of flocculant (PAM) (3.00%-8.00%), which were the main sources of sludge contributed by wastewater treatment chemicals; The control variable method was subsequently adopted to optimize the dosage of various reagents. The recommended dosages for Station A were 250 mg/L of PAC and 10 mg/L of PAM. Conclusions Considering the costs of wastewater treatment chemicals and their sludge yield, the quantitative analysis of the sludge yield of treatment chemicals for oil produced water could guide the optimization of chemicals selection. [ABSTRACT FROM AUTHOR]

Sediment microbial fuel cell (SMFC) is a type of MFC without a proton exchange membrane. However, SMFC have had problems with low-power production performance. In this paper, the effects of native bacteria (K1) in oily sludge and their electro-oil-induced domestication on the power generation and oil removal performance of SMFC were studied. The results showed that K1 belonged to Ochrobactrum intermedium. During the domestication process, an upward trend was shown in the OD600 and ORP values in the culture medium, and it grown best at 0.7 V. Ochrobactrum intermedium K1 significantly increased the average output voltage, electromotive force, and maximum power density of SMFC and reduced the apparent internal resistance of the battery. The maximum power density was 169.43 mW/m3, which was 8.59 times higher than that of the control group. Ochrobactrum intermedium K1 improved the degradation of crude oil by SMFC. Ochrobactrum intermedium K1 enhanced the degradation of high-carbon alkanes and even-carbon alkanes in n-alkanes. Cyclic voltammetry and chronoamperometry tests showed that after acclimation, Ochrobactrum intermedium K1 improved the extracellular electron transfer efficiency (EET) mediated by c-Cyts and flavin by increasing the surface protein redox potential. [ABSTRACT FROM AUTHOR]

In the process of steam injection development of heavy oil, due to the serious heterogeneity and interference of steam channeling in the high-permeability layer, there is a lot of oily sludge in the produced liquid of oil wells, which is difficult to deal with. According to existing profile control technology and the related properties of oily sludge, a profile control system was developed by using oily sludge as the main agent and by adding other additives. At the same time, the properties of sludge, the matching relationship between the particle size of sludge and the formation of pore roar, the temperature resistance, the plugging ability, and other contents were studied. The agent featured an adjustable curing time (3 to 300 h) and resistance to pressures greater than 6 MPa and temperatures greater than 350 °C. After the agent was injected into the high-permeability steam channeling, the system was cemented with the formation rock and the sealing rate was more than 85%, without any damage to the low- and medium-permeability layers. According to the different characteristics of the production well and steam injection well, the construction technology was optimized, the oily sludge profile control technology suitable for heavy oil reservoirs was formed, and the field test was carried out. At present, more than 150 wells have been used in the field, with a cumulative oil increase of 10,756 tons. The technology not only solves the environmental pollution caused by oily sludge but also reduces the cost of thermal recovery of heavy oil, with great significance for improving the final recovery efficiency and commercial benefits of the oilfield. [ABSTRACT FROM AUTHOR]