Water Injection Techniques Research Articles

The effect of hydrocarbon prices and CO2 emission taxes on drainage strategies

Secondary recovery methods, such as water and gas injection, are effective and cost-efficient techniques for enhancing hydrocarbon recovery; however, they are highly energy-intensive, leading to a large environmental footprint. This study provides insights into the challenge of balancing high hydrocarbon demand with the imperative to reduce CO2 emissions from production by estimating how drainage strategies change under varying economic parameters and CO2 tax levels. An operator’s choice of drainage strategy is assumed to be the drainage strategy yielding the highest net present value (NPV). This paper simulates the drainage strategy of an under-saturated oil reservoir, utilizing reservoir simulations and incorporating a mathematical model that represents the production processing plant. This yields hydrocarbon production, the energy required, and the resulting CO2 emissions, all incorporated into an NPV based on hydrocarbon prices and CO2 emission taxes. The drainage strategy is then optimized to maximize NPV for various hydrocarbon prices and several levels of CO2 tax on associated emissions. The findings of this study indicate that increasing gas prices favor reducing reservoir pressure below the bubble point pressure, thereby releasing solution gas and leaving oil in the reservoir. Although lower reservoir pressure reduces the energy required for injection, the resulting increase in gas production necessitates more energy for gas compression, ultimately leading to higher emissions when gas prices rise relative to oil prices. Additionally, this study reveals that for facilities well designed for the present injection and production volumes (greenfield scenarios), the impact of CO2 tax is limited, leading to a single optimal drainage strategy. In contrast, less energy-efficient facilities (brownfield scenarios) exhibit a more pronounced need to optimize drainage strategies in response to variation in CO2 tax, and oil and gas prices. This study indicates that for fields with efficient production facilities, the ratio of gas to oil prices is more important for the drainage strategy than CO2 tax levels, as income from production tends to dominate emission taxes. This implies that hydrocarbon prices are more important for CO2 intensity than CO2 taxes, e.g., a gas price increase relative to oil price promotes higher CO2 intensity due to a shift towards more energy-intensive gas production whereas realistic tax levels for CO2 emissions have only a minor impact. Thus, increasing CO2 tax levels is mainly a measure impacting emissions from fields with inefficient production facilities.

Artificial Intelligence Technology on Layered Water Injection in Oilfield Development Process

Since the 1960s, researchers have worked to advance water flooding technology to address challenges like high viscosity, low fluidity, and depleting reservoirs, aiming to prevent oil fields from becoming unproductive. The integration of artificial intelligence (AI), computer vision, and advanced algorithms like BP neural networks has recently revolutionized this field. These technological advancements have upgraded water injection methodologies, overcoming past limitations and enabling real-time monitoring and dynamic control of water injection into different oil layers. This 'intelligent layering' ensures optimized water management, enhancing overall recovery rates. This overview highlights the progression of water injection techniques, critiques traditional methods' shortcomings, and delves into the cutting-edge applications of AI-driven intelligent layering systems. It serves as a valuable guide for oil industry stakeholders, equipment manufacturers, and research institutions seeking to refine water injection practices and boost hydrocarbon extraction efficiency.

A Study on the Effect of New Surfactant Proportions on the Recovery Improvement of Carbonate Reservoir

The strategy of integrating water injection and chemical additives in combining secondary and tertiary oil recovery techniques has been widely investigated in enhancing oil recovery efficiency. Nevertheless, there is a lack of sufficient evidence on the effectiveness of a mixture of cationic and nonionic surfactants combined with water injection techniques in enhancing recovery in the application of carbonate reservoirs. Therefore, it is particularly critical to explore the impact of this combination strategy in enhancing recovery in fractured carbonate reservoirs. The recovery enhancement effect can be assessed by conducting phase behavior experiments and determining interfacial tension and contact angle. Further, the effectiveness of specific surfactant ration solutions in enhancing recovery can be verified by performing drive-off experiments. The results show that low mineralization water and surfactants have a significant synergistic effect in enhancing the recovery efficiency of carbonate reservoirs, with the optimal ratio of cationic to non-ionic surfactants being 2.5:1. The optimized surfactant ratio is able to increase the recovery of carbonate reservoirs by 20% compared to the original recovery rate.

Effect of port water injection on the characteristics of combustion and emissions in a spark ignition direct injection engine

Port water injection techniques, considered as a potential solution to further enhance the combustion performance of internal combustion engines, can suppress engine knock by reducing the cylinder temperature so that the spark timing can be advanced. Although previous literature has discussed some aspects of utilizing port water injection techniques, thorough investigations on port water injection strategies, such as injection schemes, water/fuel mass ratio, etc. and their impacts on engine power output, thermal efficiency, and emissions are still not well understood. This work implements a three-cylinder engine installed with a port water injection system to investigate water injection strategy systematically. Various parameters, such as in-cylinder pressure, exhaust temperature, fuel combustion emissions, engine work, etc., were recorded for analysis. Different engine conditions were tested and recommendations were provided in optimizing the water injection design. Furthermore, this work finds that with knock suppression, port water injection can lead to 3.4%–16.7% improvements in the brake thermal efficiency under different engine operating conditions. Via the cooling effect on the exhaust gas, fuel enrichment strategy used under high speed, full load conditions can be eliminated so that particulate number emissions can be reduced by up to 96.0% with proper water injection.

Experimental Investigation for NOx Emission Reduction in Hydrogen Fueled Spark Ignition Engine Using Spark Timing Retardation, Exhaust Gas Recirculation and Water Injection Techniques

The experimental tests were carried out on a single cylinder hydrogen fueled spark ignition (SI) generator set with different spark timings (4-20°CA bTDC), exhaust gas recirculation (EGR) up to 28% by volume and water injection up to 1.95 kg/h (maximum water to fuel mass ratio of 8:1). The engine speed was kept constant of 3000 r/min. The NOx emission and thermal efficiency of engine with gasoline and hydrogen fuel operation at 1.4 kW power output are 5 g/kWh and 12.1 g/kWh, and 15% and 20.9% respectively. In order to reduce the NOx emission at source level, retarding spark timing, exhaust gas recirculation (EGR), and water injection techniques were studied. NOx emission decreased with spark timing retardation, EGR, and water injection. NOx emission with hydrogen at 1.4 kW power output decreased from 12.1 g/kWh with maximum brake torque (MBT) spark timing (10°CA bTDC) to 8.1 g/kWh with retarded spark timing (4°CA bTDC) due to decrease in the in-cylinder peak pressure and temperature. The NOx emission decreased to 6.1 g/kWh with 20% EGR due to thermal and chemical dilution effect. However, thermal efficiency decreased about 33% and 17% with spark timing retardation and 20% EGR respectively as compared to that of MBT spark timing. But, in the case of water injection, the NOx emission decreased significantly without affecting the thermal efficiency of the engine and it is 5.6 g/kWh with water-hydrogen ratio of 4:1 (water flow rate of 0.92 kg/h). Water injection is the best suitable method to reduce the NOx emission in a hydrogen fueled engine compared with the spark timing retardation and EGR technique.

Low salinity water flooding in carbonate reservoirs – dissolution effect

One of the most significant research subjects in the industry of oil is the low salinity water injection techniques (LSWI). This is because there are possible benefits of raising recovery in oil as opposed to the conventional injection of seawater. Recent research has been done to find out the causes of less salinity with the injection of water in carbonated rocks presented significant findings. The primary mechanisms that are thought to lower salinity water injection are carbonate rocks dissolution, fines migration and alteration of wettability to more water wet. However, many researchers have elected to oppose the mechanism of dissolution and instead attributed high recovery of oil to be the primary wettability modification mechanism. Additionally, previous researchers provided no evidence characterizing about the rock and fluids produced in a detailed manner. This research work provides a detailed description of the underlying mechanisms, the core flood laboratory and the spontaneous imbibition in carbonate rocks. In the experiment, we carried out a series of steps using a limestone core with low permeability. This core was obtained from a nearby oilfield in Iraq and used it to study how dissolution and fines migration mechanisms take place. Moreover, in the process of carrying out the experiment and before its starting, SEM imaging analysis was used. In this case, as we carried out the experiment, we had to inject two-phase flow of sea water (SW), de-ionized water (DW) as well as soltrol-130. This was done in a sequential manner at 50 °C as well as 0.02 ml per minute. As the experiment progressed, the concentration of ions and pH value of the extracted water were measured in a continuous manner. The results obtained indicate that the rate of change in concentration of Ca2+ ions is directly proportional to the effluent pH value. By just balancing the mass, we were able to easily see the rate at which limestone dissolved as the experiment progressed. The maximum increase in pH was registered when fresh water was injected (pH=9.2). An increase in pH value can have a positive effect on altering wettability in that it can increase the alkalinity of flood water. To notice fines migration, the Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS) are used to scan the images of the inlet and outlet of the core plugs after completion the experiment. This method can indicate that dissolution can induce fines dislodgement for the surface of the rock. The two mechanisms of fine migration and carbonate rock dissolution can significantly increase recovery of oil and at the same time inject water low in salinity.

Experimental investigation of the performance of an effective self-suctioning water mist generator for controlling underground coal fires

Coal fires represent a worldwide hazard, and water mist is used as an effective means in controlling the fires. In the present study a new self-suctioning water mist generator was developed that produces efficient atomization at a relatively low pressure without the need for compressed air and improving the applicability of water mist systems in coal fire areas. The effects of structural parameters of the generator and operational variable (water supply pressure) on atomization performance were investigated. Both laboratory experiments and field tests were conducted to assess the fire suppression efficiency and cooling effects of this generator. The results show that the generator can attain a high degree of atomization after the optimization on the structural parameters and operational variable. The water mist produced by this device was also demonstrated to effectively suppress coal combustion. Compared with traditional water injection techniques, this new approach created more temperature decrease during a same period of application time while consuming an equal amount of water. This work therefore provides a practicable technique for the effective control of underground coal fires.

Control of backfire and NOx emission reduction in a hydrogen fueled multi-cylinder spark ignition engine using cooled EGR and water injection strategies

The experimental study was carried out on a constant speed multi-cylinder spark ignition engine fueled with hydrogen. Exhaust gas recirculation (EGR) and water injection techniques were adopted to control combustion anomalies (backfire and knocking) and reduce NOx emission at source level. The experimental tests were conducted on the engine with varied EGR rate (0%–28% by volume) and water to hydrogen ratio (WHR) (0–9.25) at 15 kW load. It was observed from the experiments that both the strategies can control backfire effectively, but water injection can effectively control backfire compared to EGR. The water injection and EGR reduce the probability of backfire occurrence and its propagation due to the increase in the requirement of minimum ignition energy (MIE) of the charge, caused mainly due to charge dilution effect, and reduction in flame speed respectively. The NOx emission was continuously reduced with increase in EGR rate and WHR, but at higher rates (of EGR and WHR), there was an issue of stability of engine operation. It was found from the experimental results that at 25% EGR, there was 57% reduction in NOx emission without drop in brake thermal efficiency whereas, with WHR of 7.5, the NOx emission was reduced by 97% without affecting the efficiency. The salient point emerging from the study is that water injection technique can control backfire with ultra-low (near zero) NOx emission without compromising the performance of the hydrogen fueled spark ignition engine.

Water-Injection Techniques Increase Recovery in Conventional Gas Reservoirs

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 191206, “Exploiting Water-Injection Techniques for Increasing Gas Recovery in Conventional Gas Reservoirs,” by Keval Darvesh Rambaran, SPE, Sarah Tammie Chin Chee Fat, SPE, and Lugard Evans Layne, SPE, University of Trinidad and Tobago, prepared for the 2018 SPE Trinidad and Tobago Section Energy Resources Conference, Port of Spain, Trinidad and Tobago, 25–26 June The paper has not been peer reviewed. Primary gas recovery for a volumetric reservoir ends when the reservoir pressure declines below the value required to flow gas to the surface at the sales-line pressure. Secondary gas-recovery techniques can then be used to increase the recovery. The most common of these techniques is gas compression, but another feasible technique that is rarely explored is water injection. This paper evaluates the incremental benefit of water injection in a conventional gas reservoir when compared with gas compression. Introduction An operator hopes to increase the recovery in Reservoir TM-20 in the Sorrel Field offshore Trinidad and Tobago by use of water injection once the technique is deemed more economical than gas compression. The wells in the reservoir are drilled from the Tamarind Platform, which also acts as a hub for the separation of fluids from fields in the immediate vicinity. Gases and liquids are piped through separate lines, with the liquids heading to the onshore liquid-processing facility. However, the company can modify the platform separators to operate in three phases and use the produced water for injection. Company records show that the average water-production rate from the platform is approximately 5,000 BWPD. If the shut-in wells were to be opened, roughly 10,000 BWPD of produced water and 15 MMscf/D of gas would be added for each well until liquid loading, thus increasing gas output significantly. Field History The Sorrel Field is a retrograde gas-condensate field located in the Columbus Basin, which has been producing from the TM-20 reservoir since 1998. The reservoir is a faulted sandstone formation of good quality that is divided into two hydrocarbon-bearing segments and underlain by an active aquifer. Segments 1 and 2 have been producing from Wells X and Y and Wells A and B, respectively, as shown in Fig. 1. Unlike Segment 1, primary gas recovery in Segment 2 ended because of a decline in the reservoir pressure, thus making it a suitable choice for water injection. Segment 2 is a wedge-shaped structure bounded by two faults, with both faults being interpreted as sealing. Production in Segment 2 began in April 1999 with a reservoir pressure of 4,732 psig. It ended in January 2014 because of an inability to flow at the sales-line pressure of 950 psig.

Investigations on the influence of ethanol and water injection techniques on engine's behavior of a hydrogen - biofuel based dual fuel engine

This work explores the influence of hydrogen and ethanol on improving engine's behavior of Maduca longifolia oil (MO) based dual fuel diesel engine. A mono cylinder diesel engine was tested in dual fuel mode of operation at the rated power output of 3.7 kW under variable hydrogen energy shares from 0 to the maximum allowable limit (until severe knocking i.e. upto 20%). The knock limit was further extended by injecting water and ethanol at the intake manifold and the engine's performance, emission and combustion characteristics were analyzed. In addition ethanol was also injected and introduced along with the intake air for comparison with hydrogen dual fuel mode. Dual fuel operation increased the BTE from 25.2% with neat MO to a maximum of 28.5% and 30% respectively with hydrogen and ethanol for the energy share of 15% and 38% where as the BTE was 30.8% with ND. The smoke opacity was reduced from 78% with neat MO to 58% for the hydrogen energy share of 15% which is the MEP (maximum efficiency point) whereas the smoke emission was noted as 51% with ND operation. However, hydrogen induction increased the NO (nitric oxide) emission. Injection of water and ethanol at the inlet was observed to extend the knocking limit with improved BTE. The BTE reached a maximum of 30.1% with 5% water and 30.8% with 10% ethanol injection. The MEPs were arrived as 31% and 30% hydrogen energy shares respectively with 5% water and 10% ethanol injection. It was concluded that hydrogen induction can be very effective in improving the diesel engine's performance when using MO as base fuel when operating on dual fuel mode. The performance could be improved by extending the knock limit by injecting ethanol and water along with hydrogen.

Displacement mechanisms of air injection for IOR in low permeability light oil reservoirs

Air injection into light oil reservoirs has been proven to be a valuable improved oil recovery (IOR) process and is being successfully implemented worldwide in many oilfields. It specially offers unique technical and economic opportunities for tertiary or secondary oil recovery in light oil reservoirs with low permeability in which conventional water injection techniques have been unsuccessful and/or uneconomical. This paper provides a comprehensive overview on the oxidation and IOR process of air injection into low permeability light oil reservoir based on detailed analysis of some field projects and the results of laboratory testing and reservoir simulation of a typical light oil reservoir, the Q131 Block. The reaction mechanisms of low temperature oxidation (LTO) and high temperature oxidation (HTO or in-situ combustion) are particularly addressed in this study. Air flooding displacement efficiency experiment was carried out without water injection, and an oil recovery of more than 40% of hydrocarbon pore volume (HCPV) was observed. A series of high-pressure oxidation experiments using the typical light oil were conducted in the temperature range of 98°C to 180°C. The results showed high oxidation and carbon dioxide (CO2) conversion rates, which are both favourable in terms of oxygen consumption. A conceptual full field compositional reservoir simulation model of the targeted low permeability block was also used to examine the reaction schemes, thermal effect of LTO reactions and IOR mechanisms. [Received: March 22, 2014; Accepted: February 7, 2016]

Displacement mechanisms of air injection for IOR in low permeability light oil reservoirs

Air injection into light oil reservoirs has been proven to be a valuable improved oil recovery (IOR) process and is being successfully implemented worldwide in many oilfields. It specially offers unique technical and economic opportunities for tertiary or secondary oil recovery in light oil reservoirs with low permeability in which conventional water injection techniques have been unsuccessful and/or uneconomical. This paper provides a comprehensive overview on the oxidation and IOR process of air injection into low permeability light oil reservoir based on detailed analysis of some field projects and the results of laboratory testing and reservoir simulation of a typical light oil reservoir, the Q131 Block. The reaction mechanisms of low temperature oxidation (LTO) and high temperature oxidation (HTO or in-situ combustion) are particularly addressed in this study. Air flooding displacement efficiency experiment was carried out without water injection, and an oil recovery of more than 40% of hydrocarbon pore volume (HCPV) was observed. A series of high-pressure oxidation experiments using the typical light oil were conducted in the temperature range of 98°C to 180°C. The results showed high oxidation and carbon dioxide (CO2) conversion rates, which are both favourable in terms of oxygen consumption. A conceptual full field compositional reservoir simulation model of the targeted low permeability block was also used to examine the reaction schemes, thermal effect of LTO reactions and IOR mechanisms. [Received: March 22, 2014; Accepted: February 7, 2016]

A comprehensive review of low salinity/engineered water injections and their applications in sandstone and carbonate rocks

Abstract The low salinity/engineered water injection techniques (LSWI/EWI) have become one of the most important research topics in the oil industry because of their possible advantages for improving oil recovery compared to conventional seawater injection. Researchers have proposed several mechanisms for the LSWI/EWI process in the literature; however, there is no consensus on a single main mechanism for the low salinity effect on oil recovery. Because of the latter, there are few models for LSWI/EWI and especially for carbonates due to their heterogeneity and complexity. In this paper, we present a comprehensive state-of-the-art review on low salinity/engineered water injection for both sandstones and carbonates. This review includes descriptions of underlying mechanisms, spontaneous imbibition and coreflood laboratory work, field-scale pilots, numerical and modeling work, implementation, comparison between sandstones and carbonates, other LSWI/EWI applications, and desalination methods. List of recommendations and conclusions are provided based on this vast literature review and our experiences. This paper can be used as a guide for starting or implementing laboratory- and field-scale projects on low salinity/engineered water injections.

A new concentric zonal water injection technique for highly-deviated wells

Abstract Existing eccentric zonal water injection techniques cannot meet the requirements of separated layer water injection, testing and adjustment in highly-deviated wells, because of their low fishing success rate of down-hole nozzles, low efficiency of connection between instruments and nozzles, and low precision of zonal flow rate test. A new concentric zonal water injection technique is proposed for highly-deviated wells. This technique adopts concentric testing and adjustment, i.e., the test instrument is concentrically connected with the down-hole regulator, with high success rate of connection. The down-hole regulator uses bridge-type channel to effectively eliminate inter-layer interference and thereby improving testing and adjustment efficiency. Water flow rate is adjusted with an eccentric valve, which features small loss in full-off state, small adjustment torque and easier water adjustment. This technique is functional for both collected flow test and non-collected flow test, so it is workable for low flow rate test. It can achieve packer seal test on line by cable, the status of seal balls can be monitored and all seal test operations can be completed in one trip. This technique can obtain flow rate, pressure, temperature and other parameters of any layer on line and automatic testing and adjustment of injection allocation rate, without fishing, significantly improving testing and adjustment efficiency. Until now, this technique has been tested in 11 wells (maximum well deviation of 55°), with tested flow rate error of less than 5%, and three-layer seal check and adjustment time of less than one day. Compared with the existing techniques, this new technique has advantages such as high testing and adjustment efficiency, high precision and low cost.

Evaluation of water injection effect on compressor and engine performance and operability

Gas turbine performance enhancement technologies such as inlet fogging, combustor water/steam injection and overspray are being employed by users in recent years without fully evaluating their effect on gas turbine performance and operability. The water injection techniques can significantly affect the engine operating point thus a careful analysis should precede the application of performance enhancement devices, especially when the devices are retrofitted to old engines or engines operating at extreme conditions. The present paper examines the most widespread techniques that implement water injection by using in-house models that can reproduce the effects of water injection on the gas turbine and compressor off-design operation. The results are analyzed with respect to both performance augmentation and engine operability in order to give further insight on gas turbine operation with water injection. The behaviour of the gas turbine is interpreted while the risks on engine integrity due to water injection are identified.

Simulação de técnicas de engenharia de reservatórios: exemplo de utilização de opções reais

Este trabalho teve como objetivo incluir flexibilidade gerencial (tais como técnicas de recuperação complementar de óleo) na avaliação de reservatórios. Concluímos que essas técnicas podem aumentar o valor dos reservatórios em até 25% segundo a teoria de opções reais. A principal vantagem da metodologia de teoria de opções em relação à tradicional técnica de fluxo de caixa descontado é levar em conta as questões operacionais da indústria do petróleo. Utilizamos dois modelos clássicos para a precificação de reservatórios de petróleo e aplicamos uma análise de sensibilidade para determinar quais fatores são mais relevantes no seu valor econômico. Como era de se esperar, em ambos os modelos, o tempo de concessão e a taxa de convenience e/ou dividend yield foram os fatores mais importantes.

Separate Production Techniques for Multiple Zones in Daqing Oil Field

Summary Daqing oil field is a heterogeneous multizone sandstone reservoir. It had serious water channeling and zonal interference troubles; therefore, a set of single-tubing separate zone production techniques including separate zone injection, separate zone production, separate zone stimulation, and production logging, were developed and used successfully in the oil field. Introduction Daqing oil field has been developed for 21 years. Because this oil field is very large and the edge water is relatively inactive, early internal injection of water (at the same time the oil field was put on production) was practiced to maintain the pressure of the reservoir at its practiced to maintain the pressure of the reservoir at its original level. However, there are more than 40 separate zones in this reservoir, the viscosity of the crude oil in the reservoir is 0. 05 to 0. 10 Pas (5 to 10 cp), and there is considerable difference between the permeability of different zones and of different parts and different directions in a single zone. When a well is produced, the fewer separate zones it is divided into the higher the diversity factor (which is the thickness-weighted mean of the permeability variance of the zones) (Fig. 1). Water channeled in the high-permeability layers. To cope with these problems, separate zone production techniques are used. In these 21 years, Daqing oil field has used an entire set of separate-zone production techniques applicable to multizone sandstone reservoirs of medium depth, including water injection, production, stimulation. and production logging techniques. production logging techniques. Separate-Zone Water-Injection Techniques Since early water injection was started, the reservoir pressure was maintained, and oil wells had a high pressure was maintained, and oil wells had a high flowing potential. However, new problems came up: water channeled to an oil well 250 m (820 ft) from the injector a few months after water injection was started in a pilot-test area of the oil field. After 3 years of indiscriminate pilot-test area of the oil field. After 3 years of indiscriminate injection into all zones of the central section [an area of 146 km2 (56 sq miles)] of Sartu oil field (Daqing) 60 % of the producers, at the first row (a staggered line drive is used here) already had a water cut. Also, the water cut increase per production of 1 % of original oil in place (OOIP) was 6 to 7%, but the recovery was only 5% at that time. To reduce the water-increase rate and to obtain a more evenly distributed water-injection profile, several separate-zone water-injection techniques were used in the field. The main tools of these techniques are packers and water-injection mandrels. Inflatable packers were developed first. These packers give reliable performances and are highly adaptable [OD of the packer is 110 mm (4 in. ), and they can be used in casing with a range of 118 to 132 mm (4. 6 to 5. 2 in. ) ID]. Any time after water injection is stopped, water can be circulated down the annulus and up the tubing; the packers are of simple construction and are easy to run in packers are of simple construction and are easy to run in and out of the hole. Since 1963, they have been used extensively in the oil field. A weak point is that packers require a differential pressure of 600 to 800 kPa (87 to 116 psi) between the tubing and annulus to maintain psi) between the tubing and annulus to maintain inflation. To conserve energy and to diminish this differential pressure, hydraulic compression packers were pressure, hydraulic compression packers were developed. No differential pressure is needed to keep this type of packer in a compressed state. JPT P. 1521