Refinery Treatment Research Articles

Three-dimensional electro-Fenton system with steel-slag based particle electrode for the treatment of refinery spent caustic

Refinery spent caustic (RSC) is a highly contaminated wastewater originated from the petroleum refining industry with complicated chemistry and high toxicity. In this work, a novel three-dimensional electro-Fenton (3DEF) system assisted by electromagnetic induction was developed to treat an actual RSC with a chemical oxygen demand (COD) concentration of 27000–33000 mg/L. Industrial waste steel slag was used as both the particle electrode and the Fenton’s catalyst. Under optimal conditions, COD removal reached 93.6% within 90 min. Electromagnetic induction significantly enhanced COD degradation by promoting the corrosion of steel slag, inhibiting the electrode passivation, and enhancing the thermal activation of hydrogen peroxide. The reusability of steel slag was also enhanced by electromagnetic induction. Radical quenching tests demonstrate that hydroxyl radicals (•OH) played a main role in the pollutant degradation. The system is of good economic and environmental benefits with a total treatment cost of about 1.015 $/m3, achieving the objective of “treating waste with waste”.

The Evolution of the Al-Qayyarah Refinery's Treatment Plant's Effectiveness and the Impact of its Discharges on the Tigris River's Quality

The Evolution of the Al-Qayyarah Refinery's Treatment Plant's Effectiveness and the Impact of its Discharges on the Tigris River's Quality

Effective treatment of petroleum oil–contaminated wastewater using activated sludge modified with magnetite/silicon nanocomposite

The study aimed to optimize the treatment of oil refinery–contaminated wastewater through modification of the well-established activated sludge process with new nanocomposite (NC) materials to produce high-quality treated effluents for potential reuse. Refinery wastewater samples were collected from one of the major oil refineries, Alexandria, Egypt, where the operation, performance, and efficiency of the current activated sludge (AS) unit were evaluated for 6 consecutive months. Two AS bench scale PVC basins were constructed. Magnetite nanoparticles (Fe3O4 NPs) and magnetite silica (Fe3O4/silica) nanocomposite (NC) were prepared and characterized. Bioremediation trials were carried out in a sequential batch mode using Fe3O4/silica NC–modified AS and control (unmodified AS). The proposed treatment produced high-quality effluents in a very short time (2 h) despite the very high initial pollutant concentration accompanied with a reduction in the produced sludge. The highest removal of TSS, TDS, BOD, COD, and OG from raw industrial wastewater recorded 78.33, 3.6, 87.65, 85.17, and 92.92% compared to 55.3, 12.6, 50.0, 40.22, and 56.84%, respectively, achieved by the unmodified AS unit. The results confirmed that integration of the AS treatment with nanomaterial composite is highly effective, promising, and economic for the treatment of highly toxic and complicated industrial wastewater such as petroleum refinery effluents.

Enhanced pollutants removal and high-value cell inclusions accumulation with Fe2+ in heavy oil refinery treatment system using Rhodopseudomonas and Pseudomonas

Metal ions has been widely used as a method of improving pollutant removal efficiency in wastewater biological treatment system. In order to enhance pollutants removal and high-value cell inclusions accumulation in heavy oil refinery wastewater treatment systems using PSB, different reactors were built feeding with different Fe2+ concentrations respectively, and run with enriching Rhodopseudomonas and Pseudomonas in the reactors. Solute chemical oxygen demand (SCOD), ammonia (NH4+-N), nitrate nitrogen (NO3−-N), nitrous nitrogen (NO2−-N), Fe2+, and related cell inclusions were all detected, moreover, microbial community structure and the quantity of Rhodopseudomonas and Pseudomonas were also detected. The results showed that at the optimal dosage of Fe2+ with 20 mg/L, the corresponding removal ratios of solute chemical oxygen demand and ammonia were 73.51% and 92.26%, respectively. The yields of carotenoid, bacteriochlorophyll, and coenzyme Q10 were 11.18, 6.75, and 9.84 mg/g-DCW respectively. Furthermore, with 20 mg/L Fe2+ dosage, the relative abundance and gene number of Rhodopseudomonas were the highest in the system, which were 91.57% and 1.843 × 106 gene copies/μL, while Fe2+ had no obvious effect on the growth of Pseudomonas. The results showed that adding Fe2+ has improved the removal of pollutants and accumulation of high-value cells inclusions, also provided theoretical guidance for the treatment of heavy oil refinery wastewater using PSB.

Poly aromatic hydrocarbons degradation by lignin peroxidase produced from local isolate Aspergillus terreus SG777

Lignin peroxidase produced from A. terreus SG777 precipitated with 80% ammonium sulfatesaturation then desalting by dialysis against Tris buffer solution and partially purified by ionexchange chromatography using DEAE- cellulose.The specific activity reached 56.67U/mg withpurification fold was 5.4 times and 13.7% recovery. The optimum pH for activity and stability was(3). The maximum activity was observed at 40°C and the enzyme maintained the activity when itwas incubated at (25-35)˚C.Degradation of poly aromatic hydrocarbons when incubated with 65.51 U/ml lignin peroxidaseat (40°C) for 4 hr compared with the Refinery treatment. Results showed (97.54%) removalefficiency of Di benzo (a, h) anthrancene by lignin peroxidase, while only (54.37%) was treated byRefinery treatment. Flourene and anthrancene degradation (95.98%) and (83.51%) respectively,while the flourene and anthrancene degradation treated by Refinery treatment only 84.51% and(46.83%) respectively.The aim of this study was degradation of poly aromatic hydrocarbons by using partialpurification lignin peroxidase.

Comprehensive characterization of an oily sludge from a petrol refinery: A step forward for its valorization within the circular economy strategy

Refinery treatment plants produce large quantities of oily sludge during the petroleum refining processes. The hazardousness associated with the disposal of these wastes, make necessary the development of innovative technologies to handle it adequately, linked to the concepts of circular economy and environmental sustainability. This work provides for the first time a methodology for the deep characterization of this kind of wastes and consequently new insights regarding its valorization. A review of works dealing with the characterization of this type of wastes has been addressed evidencing the complexity and variability of these effluents. The oily sludge under study contains a high concentration of Chemical Oxygen Demand of 196 g COD/L, a Total Kjeldahl Nitrogen of 2.8 g TKN/kg, a phosphorous content as PO43− of 7 g/kg, as well as a great presence of heavy metals in a different range of concentrations. This sludge is composed of three different phases: oily, aqueous and solid. The oily and the solid phases present high percentages of carbon content (84 and 26%, respectively), related to the presence of alkanes ranged from n-C9 to n-C44. Therefore, it could be possible their valorization by the synthesis of catalyst and/or adsorbents. A dark fermentation process could be also proposed for the oily phase to obtain H2 as an alternative energy source. Finally, the aqueous phase contains low carbon and nutrients concentration. A previous thermal pre-treatment applied to the oily sludge might increase nutrient and organic loading in the aqueous phase due to solid destruction, making this aqueous effluent suitable for a further conventional biological treatment.

Valorization of Opuntia ficus-Indica Pads and Steel Industry FeCl 3 -Rich Rejection for Removing Surfactant and Phenol from Oil Refinery Wastewater Through Coagulation-Flocculation

Background.Refinement of crude vegetable oil generates a large amount of wastewater and is a source of water pollution due to the presence of surfactants and phenols. Phenols are toxic aromatic compounds that can be lethal to fauna and flora, entraining the deceleration or blocking of the self-purification of biological treatments. In addition, surfactants can limit biological processes by inhibiting microorganisms that degrade organic matter.Objectives. The aim of the present study was to evaluate the treatment of refinery rejects loaded with phenols and detergents by coagulation flocculation using cactus pads (genus Opuntia) as a bio-flocculant and 30% iron(III) chloride (FeCl3) for surfactant and phenol removal. In addition, operating costs were evaluated for these pollution mitigation methods.Methods.The effectiveness of cactus pads as a bio-flocculant and 30% FeCl3 for surfactant and phenol removal were studied using a jar test. The study was conducted on vegetable oil refinery wastewater from a refinery company in Casablanca, Morocco.Results.The pollution load in wastewater varied widely from day to day. We evaluated the effect of cactus juice and 30% FeCl3 on high and low pollution loads. Opuntia pads showed a favorable potential for the treatment of low pollution load wastewater, with 78% and 90% of surfactant and phenol removed, respectively. However, the removal of high pollution load was less effective (42% and 41% removal of surfactant and phenol, respectively). The turbidity of low and high pollution load was reduced by 98.85% and 86%, respectively. The results demonstrate that 30% FeCl3 can effectively treat both low and high pollution loads (90% and 89% phenol removal, respectively, and 90% and 70% surfactant removal, respectively (optimal concentration 1.48 g/l). The turbidity was reduced by over 96% for both high and low pollutants.Conclusions.The results of the present study indicate that cactus as a natural flocculant and reject rich in FeCl3 could be effectively used for the low-cost effective treatment of crude vegetable oil refinery rejects.Competing Interests.The authors declare no competing financial interests

The phenomenon of bitumen ‘bee' structures – bulk or surface layer – a closer look

ABSTRACT Bitumen is the primary binder of asphalt covering most of the roads in the world. The origin of the primary oil, the refinery treatment, the specific chemical structure, and the natural or induced chemical modifications determine the mechanical properties of bitumen. Aging affects the time evolution of its thermo-rheological behaviour. Numerous studies have suggested that the particular local microstructure of bitumen affects its rheological properties including ‘bee’ – patterned structures. We have used scanning probe microscopy to distinguish between surface effects and bulk properties. Using scanning probe microscopy we conclude that the ‘bee’ structures exist at the surface only and do not occur in the bulk. In particular, they are not observed on freshly fractured surfaces. A special technique was used to chisel off the bitumen surface. The material relaxes and the ‘bee’ structures disappear from the surface. This proves that the ‘bees’ are formed as a thin surface layer. Improved recycling will thus have to rely on chemical treatment of aged and used bitumen rather than on intentional modifications to the surface microstructure which is merely a surface effect. The bitumen surface microstructure can nevertheless be seen as a fingerprint of the overall bitumen properties to a certain degree.

Emerging role of organic acids in leaching of valuable metals from refinery-spent hydroprocessing catalysts, and potential techno-economic challenges: A review

Petroleum refineries are known to generate huge quantities of spent hydroprocessing catalysts as solid waste every year. Spent hydroprocessing catalysts contain significant quantities of different toxic metals, and are designated as hazardous. Besides environmental concerns, the metals (Ni, V, Mo, Co, etc.) present in the spent hydroprocessing catalysts are also a valuable commodity and thus effective and eco-friendly methods are required to recover them. In recent years, different hydrometallurgical processes have been developed to leach these metals from spent hydroprocessing catalysts in an effective manner. Among various methods, the use of different organic acids is gaining attention as a promising green leaching method for spent catalyst due to their effectiveness, selectivity, and biodegradable nature. In this article, the properties and mechanism of different organic acids in leaching of metals from the refinery-spent hydroprocessing catalysts are reviewed. The advantages of organic acids as compared to other hydrometallurgical processes are emphasized. The potential of each organic acid in the leaching of metals from the spent hydroprocessing catalyst is elaborated. The key techno-economic challenges (efficiency, process economy, and safety) associated with the use of organic acids as leaching agents are identified, and future perspective are elaborated. Based on the analysis, it can be concluded that organic acid-based leaching might play a key role in the development of eco-friendly hydrometallurgical processes for the treatment of petroleum refinery spent hydroprocessing catalysts.

A review- bioremediation of oil sludge contaminated soil

Petroleum oil as a vast source of energy widely used in the whole world in several sectors especially in industry and transportation. The leakage or contamination of oil from pipeline, tank, and industry as a form of oil sludge with soil can produce major environmental and health hazard. Bioremediation is one of the most economical and environmentally safe technology to prevent this contamination though it takes longer time. This paper reviews the basic processes involved in bioremediation, types and the factors affecting it. This study includes some previously adopted different bioremediation methods varies with different process material such as refinery treatment sludge, sewage sludge, microbial organism, bulking agents and different chemical additives. The comparison of these methods is presented in respect of the removal efficiency of an entire process as well as the TPH (Total Petroleum Hydrocarbon), aliphatic, aromatic, resins, asphaltene fraction of oil sludge within the different period of time.

Biological treatment of toxic refinery spent sulfidic caustic at low dilution by sulfur-oxidizing fungi

One of the major concerns in petrochemical industries is eliminating hydrogen sulfide. Sodium hydroxide solutions are generally used for removing hydrogen sulfide and result in spent caustics which have a pH greater than 11 as well as high sulfide concentrations (2–3% w/v). In this study, SMHS-3 isolate was introduced with the ability to oxidize sulfur media containing sodium sulfide, thiosulfate and elemental sulfur. An analysis based on internal transcribed spacer (ITS) gene indicated that Sadat Mahale hot spring soil (SMHS-3) was closely related to Aspergillus genus. The oxidation results showed that Aspergillus sp. SMHS-3 has the highest sulfur oxidizing ability which produced sulfate in an average range of 0.85 g L−1 after 10 days. Response surface methodology (RSM) was applied to optimize the sulfur decomposition and resulted in a 1.2 fold increase in sulfur conversion rate. Aspergillus sp. SMHS-3 was used in a low-diluted spent caustic bio-treatment, resulting in a 16% reduction of COD, 10% reduction of TDS and 55% removal of active sulfite after 10 days of treatment. Results from this study suggests Aspergillus sp. SMHS-3 as a potential fungal strain for oxidizing sulfur compounds and a possible candidate for spent caustic biodesulfurization.

Petroleum refinery wastewater treatment in two-chamber microbial fuel cells (MFCS)

Petroleum refinery wastewaters (PRW) contain water-soluble hydrocarbons which can not be separated by physical methods. In recent years, there have been enormous approaches to treat PRW. The most outstanding methods involve biological, photocatalytic, electro photo-Fenton and etc. Using microbial fuel cell is a new method to treat PRW. In the present paper, treatment of petroleum wastewater of Isfahan refinery (COD= 213.9 mg/l, PH=7.1) was investigated in twochamber microbial fuel cell having 350 mL anode and cathode capacity. Anaerobic activated sludge prepared from Isfahan refinery treatment reactors was used as inoculum. Maximum power production was 0.03 W/m2 at 33 using oxygen as cathodic electron acceptor. Also COD removal efficiency was 49.27% during 44 hr. To enhance power production of the MFC, potassium permanganate was used as cathodic electron acceptor. At temperature of 33 and 0.2 g/l permanganate concentration, the maximum power density was 0.95 W/m2 and COD removal efficiency was 78% during 44hr. Then effect of temperature and external resistance on treatment of PRW was investigated. In fact the motivation of this paper is investigation of COD removal from PRW in two-chamber MFC.

ASSESSMENT OF HOUSEHOLD REVERSE-OSMOSIS SYSTEMS IN HEAVY METAL AND SOLUTE ION REMOVAL IN REAL AND SYNTHETIC SAMPLES

In this study, the efficiency of household reverse-osmosis system (HROS) with and without neutralizer accessory was investigated in both real and synthetic samples. The real samples were collected from rural and urban public drinking-water systems with and without primary refinery treatment. The selected areas were situated in the Kurdistan province, Iran. The HROS model RO100GPD with and without neutralizer accessory was used in all experiments to prevent effects of the membrane used, age of devices, and length of time in service. In order to assess sample quality, some more common physico-chemical analyses consisting of hardness, Ca 2+ , Mg 2+ , total dissolved solids (TDS), electrical conductivity (EC), alkalinity, Cl - , Br - , SO 4 2- , PO 4 3- , NO 3 - , NO 2 - , and heavy metals were performed based on standard methods. The results indicate that HROS and neutralizer accessory have significant effects on the physico-chemical properties of feed water. However, the results indicate the instability of HROS output water quality, but they verify that this instability cannot reduce the output quality. Finally, results emphasize that HROS output water meets standard levels regardless of the input water quality and application of neutralizer accessory.

Electricity generation and wastewater treatment of oil refinery in microbial fuel cells using Pseudomonas putida.

Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm2 in the third cycle with a maximum current density of 0.015 mA/cm2 in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10−2% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation.

Experimental Study and Adsorption Modeling of COD Reduction by Activated Carbon for Wastewater Treatment of Oil Refinery

Application of Granular Activated Carbon (GAC) in adsorption process has been studied for the advanced treatment of municipal and industrial wastewater. Because of entering poisonous compounds such as furfural, phenol and sulfides into the oily wastewater of Tehran refinery, biological aeration basins of wastewater treatment unit may not have the desired performance of COD reduction. In this study, GAC is examined for reduction of COD effluent from the Dissolved Air Flotation (DAF) unit to achieve to the environmental and design regulations.The equilibrium batch experiments as well as dynamic adsorption tests were performed to determine the maximum adsorption capacity and the breakthrough curves of COD, respectively. The data derived from equilibrium studies were modeled using Langmuir theory and the isotherm parameters were determined at two different temperatures of 25 and 40 C. Dynamic adsorption modeling was carried out considering the axial dispersion model in the bed of GAC with the assumption of lump kinetic mass transfer and linear driving force into the solid phase. The model results of COD breakthrough curve concentration have shown a fairly good agreement with experimental results. The sensitivity analysis of the dynamic model was carried out at different temperatures, bed lengths, feed flow rate and feed concentration to have a proper insight for appropriate design of a GAC fixed bed.It is concluded that GAC fixed bed could be an auxiliary unit for biological treatment of wastewater to overcome the problems of biological basin in oil refineries.

Native Bacterial Mixed Culture: A Proportionate Solution for Refinery and Petrochemical Wastewaters

Background: Heat, chemical and organic pollution are three types of environmental pollution, caused by refinery and petrochemical industries. Problems caused by hear and chemical pollutants are currently resolved to some extent but organic pollution such as Poly Aromatic Hydrocarbons (PAHs) are still considered as important problems of industry and environment. Objectives: A laboratory study was carried out to investigate the effects of native bacterial mixed culture (BMC) isolated from mixtures of refinery and petrochemical wastewaters for treatment of wastewaters of refinery and petrochemical industries. Materials and Methods: All bacteria were isolated from two refineries and two petrochemical plants of Iran. Several bacterial strains from both kinds of wastewater were mixed and two final stock culture collections (BMC a and BMC b ), showed the ability to improve the growth among strains. BMC a was added to the refinery wastewater (activated sludge influent sample) and BMC b was added to petrochemical wastewater (activated sludge influent sample). The effects of continuous and non-continuous aeration at high and low pressures, along with the effects of nutrient addition in the beginning of experiment versus sequential addition at specific time intervals, were studied. Results: Native BMC, when continuous high level aeration was used, decreased chemical oxygen demand (COD) in refinery and petrochemical wastewaters for about 81% and 63%, respectively. Gradual addition of nutrients increased COD removal of refinery and petrochemical wastewaters to 85% and 87%, respectively. Conclusions: Native BMCs from mixture of refineries and petrochemical wastewaters can be an effective method of wastewater treatment of both regional refinery and petrochemical plants. High pressure continuous aeration and gradual nutrient addition to the native BMCs can improve bioremediation of organic wastewater in different industries.

Biological treatment of refinery spent caustics under halo-alkaline conditions

The present research demonstrates the biological treatment of refinery sulfidic spent caustics in a continuously fed system under halo-alkaline conditions (i.e. pH 9.5; Na+= 0.8M). Experiments were performed in identical gas-lift bioreactors operated under aerobic conditions (80–90% saturation) at 35°C. Sulfide loading rates up to 27mmolL−1day−1 were successfully applied at a HRT of 3.5days. Sulfide was completely converted into sulfate by the haloalkaliphilic sulfide-oxidizing bacteria belonging to the genus Thioalkalivibrio. Influent benzene concentrations ranged from 100 to 600μM. At steady state, benzene was removed by 93% due to high stripping efficiencies and biodegradation. Microbial community analysis revealed the presence of haloalkaliphilic heterotrophic bacteria belonging to the genera Marinobacter, Halomonas and Idiomarina which might have been involved in the observed benzene removal. The work shows the potential of halo-alkaliphilic bacteria in mitigating environmental problems caused by alkaline waste.

Economic analysis for wet oxidation processes for the treatment of mixed refinery spent caustic

AbstractSodium hydroxide (caustic) continues to be one of the primary reagents used in refineries and petrochemical plants to extract hydrogen sulfide, mercaptans, and organic acids from hydrocarbon streams. A local refinery had accumulated ∼5000 m3 of spent caustics containing cresylic and naphthenic compounds. The chemical oxygen demand (COD) concentrations must be reduced to less than 1 g/L prior to discharge to biotreatment. A simple and safe treatment system for this high volume and high concentration of COD is desired. Bench‐scale treatment of spent caustic by the Fenton's reagent process had a total COD removal of greater than 95%, and the effluent COD was lower than 1 g/L. The process was operated at a temperature lower than 80°C and ambient pressure. The capital cost was thus lower than that of the wet air oxidation (WAO) process that normally operates at 200°C and 28 bars. The cost of exporting spent caustic to a full‐service company in USA was $1.21 per gallon that was competitive with treatment at the individual generation sites on a short‐term basis. © 2008 American Institute of Chemical Engineers Environ Prog, 2008

Experimental study on municipal and industrial reclaimed wastewater refinement for agricultural reuse

The present study is aimed at verifying the possibility of reusing municipal and industrial reclaimed wastewaters for the irrigation of container-grown ornamental shrubs, paying attention to the refinery treatment. The research has been carried out in the district of Pistoia (Central Italy), which represents one of the main nursery areas in Europe. Two experimental sites, each consisting of a refinery treatment pilot plant (filtration and disinfection) and an agronomic area, were set-up. In this paper the attention is focused on the selection of the refinery treatment. The combined process of peracetic acid (PAA) and ultraviolet irradiation (UV) chosen for the disinfection treatment proved to be very effective for the inactivation of microorganisms for both municipal and industrial wastewaters. The high efficiency is recognised as being brought about by the formation of free radicals due to the photolysis of the PAA when in the presence of the UV rays. A preliminary cost analysis has been carried out in order to highlight the most economically advantageous solution which guarantees the compliance to the Italian limits for wastewater reuse in agriculture (Escherichia Coli 10 CFU/100 mL).

Reuse of industrial wastewater for the irrigation of ornamental plants

This paper describes the results of experimental activities carried out for verifying the possibility of reusing reclaimed wastewater originated from textile (70%) and domestic (30%) activities for the irrigation of container-grown ornamental shrubs. Aspects that concern the refinery treatment of reclaimed wastewater and the effect of irrigation on some ornamental plant species were investigated. An experimental site consisting of a refinery treatment pilot plant (filtration and disinfection) and an agronomic experimental area was set-up. The combined treatment of PAA and UV, used for the disinfection, showed to be very effective for inactivation of E. coli with most of PAA and UV dose combinations able to assure total inactivation. The plants (Buxus, Photinia, Pistacia and Viburnum), sprinkle and drip irrigated with well water (WW), reclaimed wastewater (RW) and a water mixed (MW) between reclaimed wastewater and well water (1:1 by vol), showed interesting results. A similar growth among different treatments was achieved for Buxus and Pistacia, while Viburnum and Photinia plants showed a higher sensibility to MW and RW. Photinia, in particular, turned out to be very sensitive to sprinkle irrigation with the reclaimed water, while the drip irrigation had no such bad effects, as reported in previous works.