Oilfield Produced Water Research Articles

Influence Factors and Elimination on Iron Content Using ICP-AES Method in Oilfield Produced Water

ICP-AES method can be used to determine multiple metallic elements simultaneously, and has the advantages of high sensitivity, good repeatability and high accuracy. In the paper, the detection limit of iron content was determined by stepwise dilution method. The influence of the cationic concentration on the determination of iron element was studied, and the matrix matching method was proposed to eliminate the influence. The results show that, the determination limit of Iron element is 0.01 mg·L-1. Because the other cationic content is several times or even tens of times as much as iron ions, it has a great influence on the determination results of Iron element. The effects of cationic concentration can be effectively eliminated by establishing a standard curve using matrix matching. After digestion pretreatment on the oil and gas field produce water, The standard adding recovery rate was between 95% and 105%, and the RSD is less than 4%. Compare this method with o-phenanthroline spectrophotometry, its relative error is within 5%. Therefore, ICP-AES method can fully meet the requirements of determination of iron content in oil field produce water, and greatly improves the efficiency and accuracy of the laboratory analysis of oil and as field wastewater.

Initiation and inhibition of pitting corrosion on C-steel in oilfield-produced water under natural corrosion conditions

Initiation and inhibition of pitting corrosion on C-steel in oilfield-produced water under natural corrosion conditions

Inhibition of pitting corrosion of C-steel in oilfield-produced water using some purine derivatives

Inhibition of pitting corrosion of C-steel in oilfield-produced water using some purine derivatives

Omniphobic Braid-Reinforced Hollow Fiber Membranes for Dcmd of Oilfield Produced Water: Understanding the Effect of Process Conditions on Membrane Performance

Omniphobic Braid-Reinforced Hollow Fiber Membranes for Dcmd of Oilfield Produced Water: Understanding the Effect of Process Conditions on Membrane Performance

Effect of Marine Streptomyces on Corrosion Behavior of X65 Steel in Simulated Offshore Oilfield Produced Water System

Effect of Marine Streptomyces on Corrosion Behavior of X65 Steel in Simulated Offshore Oilfield Produced Water System

Implementation of a process for the treatment of hydrocarbon-contaminated soil using petroleum production water

Oil-Pipeline and Oil-Well accidents, and leaky underground storage Oil-tanks can all permanently contaminate massive areas of soil, making them economically useless as well as dangerous to the human health, biological resources, and ecosystems. There are many method of treatment of these contaminated soil by hydrocarbons [1]: stabilization/solidification, bioremediation [2], incineration, soil washing, etc. The present work focuses on the treatment of the contaminated soil by the hydrocarbons with soil washing process using oilfield producedwater (PW). The methodological approach consists of researching the optimum conditions of soil washing based on the optimum of moisture’sparametersbetween PW and contaminated soil such as Liquid/Solid ratio and Liquid/Solid contact time. Another parameter was analysed, it is the successive wash test. The contaminated soil before applying the treatment has 1900 ppm of Total Petroleum Hydrocarbons (TPH). After many washing test, the optimum parameters of test were fixed as follow: The optimum of Liquid/Solid ratio was 100 ml / 100 g and the optimum of Liquid/Solid contact time was 5 minutes.With these optimum conditions and after 4 successive soil washing, we succeeded to reduce the percentage of residual TPH in contaminated soil from 1,9%(1900 ppm) to 0,1% (100 ppm). Keywords:Petroleum industry, Produced Water (PW), Contaminated soil, Total Petroleum Hydrocarbons (TPH), Soil washing.

Recent advances, influencing factors, and future research prospects using photocatalytic process for produced water treatment.

Oilfield-produced water is the primary by-product generated during oil and gas extraction operations. Oilfield-produced water is often severely toxic and poses substantial health, safety, and environmental issues; adequate treatment technologies can bring these streams to a quality level. Photocatalysis is a photochemical catalytic reaction that is a highly promising tool for environmental remediation due to its efficiency in mineralizing persistent and potentially toxic contaminants. However, there is limited understanding of its application to treat oilfield-produced water with a complex and highly variable water composition. This review article discusses the mechanisms and current state of heterogeneous photocatalytic systems for oilfield-produced water treatment, highlighting impediments to knowledge transfer, including the feasibility of practical applications and the identification of essential research requirements. Additionally, the effects of significant variables such as catalyst quantity, pH, organic compound concentration, light intensity, and wavelength are discussed in detail. Some solutions are proposed for scientists and engineers interested in advancing the development of industrial-scale photocatalytic water treatment technologies.

Investigation of Tetraazaadamantane as Corrosion Inhibitor for Mild Steel in Oilfield Produced Water Under Sweet Corrosive Environment

Investigation of Tetraazaadamantane as Corrosion Inhibitor for Mild Steel in Oilfield Produced Water Under Sweet Corrosive Environment

The Influence of Production Chemicals on the Quality of Oilfield Produced Water

The Influence of Production Chemicals on the Quality of Oilfield Produced Water

Application of Moving Bed Biofilm Reactor and Fixed Bed Hybrid Biological Reactor for Oilfield Produced Water Treatment: Influence of Total Dissolved Solids Concentration

This experimental paper deals with the development of a hybrid biological reactor for the treatment of a synthetic oilfield produced water under an increase in total dissolved solids (TDS) concentration. To comply with strengthening regulations concerning produced water discharge and peculiar produced water compositions, a moving bed biofilm reactor (MBBR) consisting in a combination of free activated sludge and moving biofilm supports was compared to a fixed bed hybrid biological reactor (FBHBR) consisting in a combination of free activated sludge and a fixed biofilm support. After a 216 days experimental period, the MBBR and the FBHBR were efficient to treat a synthetic produced water with chemical oxygen demand (COD) removal rate above 90% under an increase in TDS concentrations from 1.5 to 20 g·L−1. Ecotoxicity measurements on freshwater and marine microorganisms revealed an absence of toxicity on treated waters. A decrease in bacterial diversity indices with respect to the inoculum was observed in both bioreactors. This suggests that the increase in TDS concentrations caused the predominance of a low number of bacterial species.

Vulnerability of Groundwater Resources Underlying Unlined Produced Water Ponds in the Tulare Basin of the San Joaquin Valley, California.

The San Joaquin Valley (SJV) in California is one of the most agriculturally productive regions in the world relying in part on groundwater for irrigation and for domestic or municipal water supply for nearly 4 million residents. One area of growing concern in the SJV is potential impact to groundwater resources from ongoing and historical disposal of oilfield-produced water into unlined produced water ponds (PWPs). In this investigation, we utilized available information on composition of produced water disposed into unlined PWPs and levels of total dissolved solids in underlying groundwater to demonstrate that this disposal practice, both past and present, poses risks to groundwater resources, especially in the Tulare Basin in the southern SJV. Groundwater monitoring at unlined PWP facilities is relatively sparse, but where monitoring has occurred, impact to aquifers used for public and agricultural water supply has been observed and has proven to be too expensive to actively remediate. Results of this investigation should inform policy discussions in California and other locations where disposal of produced water into unlined impoundments occurs, especially at locations that overlie groundwater resources.

Study of a poly(vinylidene fluoride)/hydrophobic silica sol hybrid hollow fiber membrane for treatment of produced water via direct contact membrane distillation

Direct contact membrane distillation (DCMD) has shown great promises in remediating high-salinity oilfield produced water (PW). In our previous work, a hydrophobic silica sol (Si-R) was successfully synthesized to engineer anti-wetting ability of poly(vinylidene fluoride) (PVDF) membrane. Here our research interest lies in customizing PVDF hollow fiber membrane (HFM) with desirable stability for treating challenging oilfield PW via a DCMD process. The PVDF/Si-R hybrid HFM was fabricated under an optimized spinning condition. It is found that the fabricated PVDF/Si-R HFM is sandwich-structured, consisting a highly porous and thick middle layer and small-size macrovoids of outer layer and inner layer with different pore geometry, and the unique sandwich structure endows the membrane with superior wetting resistance. The membrane characterization showed that the liquid entry pressure (LEP) and water contact angle (WCA) of the fabricated PVDF/Si-R HFM impressively reached up to 5.25 bar and 126°, respectively. As a result, the PVDF/Si-R HFM possessed a desirable performance in treating high-salinity oilfield PW in terms of wetting resistance and salt rejection. Specifically, with a 60 h continuous DCMD operation, the PVDF/Si-R membrane exhibited over 99.9% salt rejection with only 7% reduction in permeate water flux. Clearly, the synthesized hydrophobic Si-R is a favorable additive for enhancing the antiwetting ability of PVDF HFM to treat high-salinity oilfield PW via DCMD process.

Organic pollutants removal from oilfield produced water using nano magnetite as adsorbent

<p>The current study investigates the ability of Nano magnetite as an adsorbent to remove organic materials from oilfield-produced water (PW). The effect of several variables on the removal procedure was investigated, such as nano magnetite dose, pH of solution and adsorption period. The adsorbent was carefully examined and completed using several approaches FTIR, SEM and surface area analyzer. The results show that the best organic removal reached more than 89 % at 0.8 g Nano magnetite dose in 120 min through pH = 6.0 at room temperature. Three mathematical isotherm models of adsorption were used in this study: Langmuir, Freundlich and Brunauer-Emmett-Teller. It seems that the Langmuir model and Brunauer-Emmett-Teller was best fitted model over the experimental variety with a correlation coefficient of 0.994 and 0.995 respectively.</p>

Use of Reverse Electrodialysis to Harvest Salinity Gradient Energy from Oilfield Produced Water

Two lab-scale electrodialysis (RED) stacks with different intermembrane spacing were used in this study. Each stack consists of two membrane pairs. Thick intermembrane spacing stack was made of four identical plexiglass sections, with outer dimensions 5 cm * 5 cm * 1.5 cm and an inner cross-section of 3 cm diameter each to construct two diluted solution compartments and two concentrated solution compartments. For the thin intermembrane spacing configuration, four rubber spacers with a thickness of 1 mm and an inner opening of 3 cm each were used instead of these sections. Two copper sheets were used as anode and cathode electrodes. Different solutions with NaCl concentrations of 15,000, 30,000 and 200,000 mg/l were used as a concentrated solution and different solutions with relatively low NaCl concentrations of 25, 1000 and 3600 mg/l were used as a diluted solution. A 30,000 mg/l NaCl solution was used as a diluted solution when the concentrated stream was with NaCl concentration of 200,000 mg/l. The electrode solution was of 15,000 mg/l (~0.25 M) NaCl and 8,000 mg/l (~0.05 M) CuSO4.5H2O. The results of this study confirmed the validity of using RED technology to harvest energy from salinity gradient using saline and freshwater available abundantly particularly in Iraq. An experiment on a synthetic hypersaline oil field co-produced water as a concentrated stream and seawater as a diluted stream showed that the system performance is reproducible and stable. A maximum power density of 0.029 W/m2 could be harvested.

Treatment Oilfield Produced Water using Coagulation/Flocculation Process (case study: Alahdab Oilfield)

Produced water is a large amount of water wasted throughout the crude oil extraction process, it's a mixture of the well's deposition water and the water of oil wells extraction water. Produced water contains oil, suspended solids and dissolves solid. This study tested produced water collected from Alahdab oilfield/middle oil company for oil content and suspended solid contamination using chemical precipitation and coagulation-flocculation for reinjection and environmental considerations. Coagulation/flocculation is a common method used as primary purification to oily wastewater treatment due to its usability, performance, and low cost. Coagulant experimental was completed by A jar test device, additives of ferric sulfate and aluminium sulfate were in a range about (10 ـ 40) ppm, as well as polyelectrolyte- (polyacrylamide) as an additional flocculent in the range (1.5-3) ppm. The results show that ferric sulfate was more efficient at removing turbidity than aluminium sulfate under the same conditions, with the best removal of turbidity at dose concentration 30 ppm of Ferric sulfate and a flocculent dose concentration of 2.5 ppm of polyacrylamide, also with oil content decreasing from 396.71 ppm to 53.56 ppm.

Potential for Biomass Production and Remediation by Cultivation of the Marine Model Diatom Phaeodactylum tricornutum in Oil Field Produced Wastewater Media

While oilfield produced water (PW) is one of the largest, unclaimed wastewater streams of the oil industry, it could potentially be used as a cultivation medium for microalgae. Microalgae could help with the remediation of this water while also delivering biomass that can be transformed into valuable byproducts such as biofuels. The coupling of these two purposes is expected to cut production costs of biofuels while aiding environmental protection. In this study, we compared the cultivation capacity of the marine model diatom Phaeodactylum tricornutum in media at varying salinities and in media composed of PW from two oilfields in the Central Valley of California that differed drastically in the concentration of inorganic and organic constituents. Specifically, we measured the carrying capacity of these media, the maximum growth rates of P. tricornutum, its cellular lipid accumulation capacity, and its capacity to remediate the most polluted PW source. Our study shows that P. tricornutum can successfully adjust to the tested cultivation media through processes of short-term acclimation and long-term adaptation. Furthermore, the cultivation of P. tricornutum in the most heavily polluted PW source led to significant increases in cell yield and improved photosynthetic capacity during the stationary phase, which could be attributed chiefly to the higher levels of nitrate present in this PW source. Chemical water analyses also demonstrated the capability of P. tricornutum to remediate major nutrient content and potentially harmful elements like fluorine and copper. Because P. tricornutum is amenable to advanced genetic engineering, which could be taken advantage of to improve its cultivation resilience and productivity in an economic setting, we propose this study as a step towards essential follow-up studies that will identify the genetic regulation behind its growth in oilfield PW media and its remediation of the PW constituents.

Mechanisms of heavy metal and oil removal from synthetic saline oilfield produced water by electrocoagulation

In the present study, an electrocoagulation process was applied to treat saline oilfield-produced water. The kinetics of simultaneous heavy metal and oil removal in the saline environment under different conditions including four-electrode materials of copper, zinc, iron, and aluminum, aeration and agitation rate, oil content, and salinity was investigated. The nature of the electro-generated species and possible abatement mechanisms were explored and compared by using FE-SEM/EDS, FTIR, XRD, and BET analyses. At low and high salinities, cadmium adsorption followed Langmuir and Freundlich models, suggesting the transformation of identical adsorption sites to heterogeneous ones. Cadmium removal efficiencies of 99/73% were obtained at low/high salinity with iron and 99.9 and 82% using copper and zinc electrodes in a saline environment. The cadmium adsorption capacity of different anode materials exhibited the order of copper > zinc > iron > aluminum. The adsorption capacity was considerably reduced in saline condition due to more crystalline structure and lower surface area and porosity of the particles while it was enhanced by the oil, caused by structural changes including more uniform pores, the elevated surface area, and porosity. The COD removal yield of 89% for low salinity and 80/73% at high salinity with/without aeration were achieved by iron. The highest COD removal yield of about 95% was achieved by the aluminum electrodes, compared to 85 and 87% for copper and zinc electrodes. The main removal mechanisms were outer- and inner-sphere complexation, and surface precipitation.

Oil Recovery from Oilfield Produced Water Using Zink Oxide Nano Particle as Catalyst in Batch and Continuous System

Oil Recovery from Oilfield Produced Water Using Zink Oxide Nano Particle as Catalyst in Batch and Continuous System

Microscopy techniques applied to submicron characterization of oilfield produced water

Produced water (PW) and formation water are complex mixtures of hydrocarbons and water produced at oil and gas upstream facilities. Submicron oil droplets represent a multitude of issues affecting the performance of downstream advanced water treatment processes, such as micro and ultra-filtration processes. Conventional de-oiling technologies do not efficiently remove submicron oil droplets in PW. An accurate characterization of submicron oil droplets and contaminants is required to improve PW treatment technology. In this study, a methodology for visualization and quantification of submicron oil droplets size distribution (DSD), using optical and electron microscopy techniques, was developed. Various microscopy techniques were evaluated, including epifluorescence microscopy (EpiFM), confocal laser scanning microscopy (CLSM), cryogenic scanning and transmission electron microscopy (cryo-SEM and cryo-TEM, respectively). Synthetic PW was used to improve and standardize the sample preparation and characterization methodology. The improved methodology was then tested with two PW samples from different oilfields in the Middle East region. Two methods were developed for the determination of DSD in oilfield PW samples. The first method is suitable for highly polydisperse PW samples with oil droplets larger than 250 nm. This method is based on using low-temperature agarose to immobilize the samples, avoiding coalescence, and allowing clear visualization of the oil droplets at high magnification in EpiFM. The second method is suitable for concentrated PW samples and oil droplets as small as 20 nm in size. This method is based on cryo-TEM with plunge freezing and without the use of agarose for sample immobilization. The agarose-immobilization technique was also applied for sample preparation in cryo-SEM. Cryo-SEM fixation by high-pressure freezing (HPF) preserved the morphology of oil droplets in synthetic oil-concentrated samples and allowed its visualization in a wide range of sizes from 50 nm up to 20 μm. Cryo-TEM imaging of oilfield PW samples revealed the presence of oil droplets as small as 20 nm in size. However, no quantification of the DSD in the oilfield PW samples was possible due to the low oil concentration. Moreover, a relatively large amount of other submicron particulates/aggregates were observed in PW samples. Cryo-SEM coupled with energy-dispersive X-ray spectroscopy (EDS) provided valuable information on the morphology and elemental composition of the submicron-sized contaminants. These submicron contaminants would not be removed by conventional de-oiling technologies and might cause intrapore blocking in membrane filtration systems downstream. The effect of these submicron contaminants, other than oil droplets present in PW, needs to be addressed to improve the PW treatment technologies.

Performance of Combined Electrocoagulation-Advanced Electrochemical Oxidation Used for Oil Field Produced Water Treatment

Considerable amounts of produced water (PW) are usually accompanied with theproduction of oil. This study proposed a combination of electrocoagulation (EC) - electro-Fenton (EF) process for oxidation organic compounds in PW to reduce the chemical oxygendemand (COD) to below regulation limits. The PW used in this study was collected fromoilfield in the Midland Oil Company. Pretreatment of the PW was conducted using batch ECtechnique with aluminum electrodes to eliminate the suspended and dissolved solids and toreduce the COD and treatment cost. Optimization of EC process revealed that optimum currentdensity, pH, and reaction time were 7.83 mA/cm2, 7.24, 20.40 minutes respectively. Underthese conditions the COD removal percentage was 73.97% starting from initial COD of 1730mg/l.Batch and continuous electro-Fenton processes were investigated using dimensionallystable anode Ti-RuO2/IrO2 and activated carbon fiber felt (ACFF) cathode. The effect ofcrucial process variables on COD removal efficiency was investigated using response surfacemethodology. A second order polynomial model equations were constructed and the resultswas analyzed by the analysis of variance (ANOVA). It was concluded that a combination ofelectrocoagulation followed by electro-Fenton process is effective for treating oilfieldproduced water and further improvement can be achieved by photo assisting the process. Atotal COR removal efficiency of 98% was achieved.