Water Injection Technique Research Articles

FLUID FLOW MODEL BASED ON THE ANALYSIS OF WATER INJECTION DATA IN THE TURONIAN RESERVOIR OF THE LIAWENDA FIELD, OFFSHORE COASTAL BASIN OF D.R. CONGO

Arranged the hydrocarbons in an oil reservoir require several techniques for their exploitation. The Liawenda field, discovered in December 1971 following the drilling of the Liawenda-01 exploration well, has a total of 186 wells with an annual production of 3,009,553 barrels. Having started production several years ago, the field has used the water injection technique following a drop in pressure. Despite this recourse to water injection methods, production from the Liawenda field is not always satisfactory. Knowledge of fluid flow inside an oil reservoir is important because it enables us to estimate certain useful parameters that can determine fluid movements in order to identify the causes of excessive water production. Thus, the present paper deals with water injection data in order to understand fluid movements in the Turonian reservoir of the Liawenda Field: - What is the fluid movement like in the Turonian reservoir of the Liawenda Field? - How does water move in relation to oil? - What are the efficiencies of fluid movement within the Liawenda Field? - What is the speed and travel time of the fluids in this reservoir? - How mobile are fluids?

Development of knock prediction technique in dual fuel engines and its mitigation with direct water injection

In the face of increasing emission restrictions and the parsimony of conventional fuels, dual fuel engine is presented as a promising solution that is satisfactory for environmental and economic aspects. However, this type of engine is limited by certain problems such as knocking, which negatively influences overall operation. For this reason and for optimal engine operation, prediction of this undesirable auto-ignition is essential. The approach developed in this work for this purpose, is based on dividing the combustion chamber into two zones to follow the thermodynamic properties of the unburnt gases where knock may occur. This thermodynamic modeling is coupled with a model based on Arrhenius equation for the auto-ignition delay as a function of crank angle. In addition, in order to make the model more predictive with the minimum of parameters to be calibrated experimentally, an analysis of variables is used for different engine conditions. The selected parameters undergo a correction before being modeled according to response surfaces methodology. After validation of the model using experimental results, it is coupled with a CFD calculation model to develop a global approach aimed at preventing knocking during dual fuel mode. The model makes it possible to predict knock onset with good precision. Consequently, preventing this phenomenon is possible. Water injection technique is therefore used for this objective. Accurate prediction was useful for knock avoidance via water injection strategy. Our results confirmed the effectiveness of this technique, justified mainly by water injection characteristics. The precision of the instant of knocking predicted by the developed model implied an optimal instant for water injection. Overall, this global model can be considered as a valuable means for knock prediction and prevention in dual fuel mode.

Production of Raphanus Sativus Biodiesel and Its Performance Assessment in a Thermal Barrier‐Coated Agriculture Sector Diesel Engine

Herein, in order to estimate the optimized process specifications, an empirical study is done for biodiesel production, performance of standard and coated engine, combustion, and discharge aspects of Raphanus sativus (radish) biodiesel. Optimization process parameters of biodiesel production are done using the response surface method. The importance of this study is that optimized biodiesel production is used to improve the biodiesel properties and fatty acid content to find suitable vegetable oil as well as a new coating material for sustainable development of the country in the field of agriculture and ecological conditions. The mechanism used in this research work is a coating for internal combustion engine components done with partially stabilized zirconia, aluminum–20% silicon carbide (Al–20%SiC), and titanium dioxide that acts as a ceramic composite settled above the coating that has a thickness of 450 μm by the technique called air plasma spray for test purpose. To increase the performance of an engine and reduce the emission particles like smoke density, carbon monoxide, and hydrocarbon except NO x , the partially stabilized zirconia, aluminum–20% silicon carbide (Al–20%SiC) coated engine is used under various compositions of radish biodiesel and clean diesel. To reduce NO x , the engine operation is carried out along with the TiO2 coated combustion chamber steam, and water injection technique is added to overcome the NO x formation. From this study, the resulting factor shows that adding 25% radish biodiesel (B25) and 75% clean diesel shows a reasonable reduction in emissions with comparatively better performance and combustion in the engine under consideration.

Next-Generation Pedal: Integration of Sensors in a Braking Pedal for a Full Brake-by-Wire System.

This article presents a novel approach to designing and validating a fully electronic braking pedal, addressing the growing integration of electronics in vehicles. With the imminent rise of brake-by-wire (BBW) technology, the brake pedal requires electronification to keep pace with industry advancements. This research explores technologies and features for the next-generation pedal, including low-power consumption electronics, cost-effective sensors, active adjustable pedals, and a retractable pedal for autonomous vehicles. Furthermore, this research brings the benefits of the water injection technique (WIT) as the base for manufacturing plastic pedal brakes towards reducing cost and weight while enhancing torsional stiffness. Communication with original equipment manufacturers (OEMs) has provided valuable insights and feedback, facilitating a productive exchange of ideas. The findings include two sensor prototypes utilizing inductive technology and printed-ink gauges. Significantly, reduced power consumption was achieved in a Hall-effect sensor already in production. Additionally, a functional BBW prototype was developed and validated. This research presents an innovative approach to pedal design that aligns with current electrification trends and autonomous vehicles. It positions the braking pedal as an advanced component that has the potential to redefine industry standards. In summary, this research significantly contributes to the electronic braking pedal technology presenting the critical industry needs that have driven technical studies and progress in the field of sensors, electronics, and materials, highlighting the challenges that component manufacturers will inevitably face in the forthcoming years.

A novel approach of water injection optimization applied in gasoline engines: An investigation on heated water injection

Water injection technique is a promising solution for accurate combustion control, but oil emulsion obstacle its commercial application. The present study proposes a practical approach for optimizing water spray atomization and evaporation, in which water is heated through exhaust gas recovery and directly injected into combustion chamber with a flash boiling. Firstly, a heated water injection (HWI) system was designed and established. Then, experiments were conducted to explore the effects of HWI parameters on engine combustion and emissions characteristics in terms of water injection strategies. The results present that HWI increase water evaporation rate and improves combustion efficiency. The HWI lowers flame propagation speed and improves specific heat ratio of air–fuel mixture. Elevated injection temperature lowers duration of flame kernel formation, which shortens ignition delay prolonged under conventional water injection. CA10 is advanced 4.5°CA under same spark advance while compared to conventional water injection. Moreover, HWI can not only reduce production of NOX and CO emissions but also effectively lower HC emissions by 26.2%, as water injection temperature increased to 205℃. However, excessive water injection mass and inappropriate water injection timing may worsen ignition and flame propagation, increasing unburned loss and misfire probability. The present results provide considerable evidence for the application of HWI within modern gasoline engines.

Experimental study on peat fire suppression through water injection in laboratory scale

Peat fires can persistently last for an extended period after being ignited, despite rainfall and firefighting efforts. The difficulty of peat fire suppression is mainly due to the smoldering spreading through the subsurface layer. This paper reports laboratory experiments of peat fire suppression by means of water injection directly to the subsurface hotspot. Natural peat samples (from Papua and Jambi, Indonesia) were used in this study. The experimental results show that water injection is more efficient than the water spray technique based on both suppression duration and water usage in extinguishing hotspot areas. The suppression duration of water injection is about half of those of water spray. To fully suppress the fire, Papuan peat required 4.22 ± 0.26 L of water per 1 kg of peat (L/kg-peat), while Jambi peat required 3.81 ± 0.03 L/kg-peat. This study contributes to a better understanding of the suppression dynamic of the water injection technique and proposes its implementation for early peat fire mitigation in the field.

The Effect of Injection Discharge to Reduce the Bend Scour Using Water Injection Technique

The Effect of Injection Discharge to Reduce the Bend Scour Using Water Injection Technique

Numerical analysis of the effects of port water injection in a downsized SI engine at partial and full load operation

The water injection (WI) technique represents a viable way to improve the performance of spark ignition (SI) engines. The main benefit of using this technique is to take advantage of the high heat of vaporization of water. If injected into the intake port, its vaporization cools the air–fuel mixture entering the engine. This could lead to greater spark advances, with optimal combustion phasing, and to a reduction of the combustion temperature with consequent lower heat losses. Moreover, due to the vaporization cooling effect, the heat capacity ratio of the in-cylinder gases increases. These three main factors allow improving the thermal efficiency of the engine. In this paper, the numerical simulation has been utilized in order to assess the influence of water injection on the performance of a “downsized” turbocharged spark-ignition engine. Calculations have been carried out using a 1-D model validated with respect to the experimental data of the analyzed engine. A knock model has been implemented in the 1-D model in order to identify the knock-limited parameters in engine optimization. Threshold values for knock index and exhaust turbine inlet temperature have been imposed as optimization constraints. The model has been subsequently modified by adding water injection into the intake ports. A simple thermodynamic approach has been utilized in order to obtain a first estimation of effects of water evaporation on the temperature of the fresh charge entering the cylinder and on that of the unburned mixture at the end of the compression stroke. The authors analyzed the effects of water injection at various operating points. An optimization procedure of the engine parameters in case of WI operation is presented and its effects on combustion characteristics and engine performance are described in detail. The engine control parameters have been optimized in order to obtain minimum specific fuel consumption. The most remarkable results show that, at high load operation, it is possible to increase both spark advance and air-to-fuel ratio with a consequent improvement in terms of both brake mean effective pressure (BMEP) and brake specific fuel consumption (BSFC). In particular, at full load, the BSFC registered a 12% mean improvement in the engine speed range, while BMEP mean increase was about 9%. The obtained results show water injection technique could be a useful tool in performance improving of turbocharged spark-ignition engines.

An assessment methodology for fuel/water consumption co-optimization of a gasoline engine with port water injection

For the requirements of rigorous CO2 and emissions regulations, the water injection technique is a promising solution to improve fuel economy. The establishment of an optimum water injection strategy is still a challenge when this technique is applied as a method of thermal efficiency enhancement. The present study proposes an evaluation index for the energy conservation potential of water injection strategies, which optimizes water consumption and minimizes the negative influence on energy conservation. An evaluation approach based on Brent’s method is adopted to search the optimum combination parameters of objection function, in which constraints consider fuel cost, usage cost, and space cost. A comprehensive vehicle dynamics model is established and validated to evaluate the energy conservation potential of proposed water injection strategies. The results present the proposed index provides an effective approach to assessing the trade-off relationship between water and fuel consumption. The fuel cost strategy improves fuel economy by 5.2% along the WLTC driving cycle, but this strategy consumes a large amount of water (1.08 L/100 km). In contrast, the proposed usage and space cost strategies save water consumption to 0.58 L/100 km and 0.29 L/100 km, respectively, although their ability to fuel conservation reduces to 4.8% and 4.5%, correspondingly. The comparison results provide considerable guidance on the selection of water injection strategies for vehicle designers and customers according to their purposes and demands.

Evaluating the outcomes of a single-cylinder CRDI engine operated by lemon peel oil under the influence of DTBP, rice husk nano additive and water injection

In the search for an alternative energy source with lesser pollution for transportation needs, bio-oil, a denser and viscous fuel that needs a transesterification process, have been widely considered for diesel engines. However, these problems are solved by using low viscous biofuel, but this improvement also significantly leads to increased NOx emission. Hence this present study investigates the usage of a low viscous biofuel in the CRDI engine with measures to reduce NOx emission through water injection technique. The low viscous bio-oil was used in this study along with an ignition enhancer (di-tert-butyl-peroxide), non-metallic nano additive (rice husk). They were tested in a constant speed, single-cylinder, diesel engine for various loads. Considering the brake thermal efficiency (BTE), 2% and 150 ppm were selected as the optimum value after testing five ratios (1%, 1.5%, 2%, 2.5% and 3%) of di tert butyl peroxide (DTBP) and four ratios (50, 100, 150 and 200 ppm) of rice husk (RH). The lemon peel oil (LPO) with the optimum additive ratio produced 30.69% BTE, which was 4.7% lesser than diesel fuel. A considerable decrease in fuel consumption and emissions except for nitrogen oxides (NOx) is recorded. NOx emission increased by 17.3% for the biofuel blend containing RH and DTBP. To control NOx emission, 2% of water was injected into the intake manifold with the fresh intake air. Two percent by vol. was finalised after experimenting four ratios (1%, 2%, 3% and 4%) of water addition. This 2% water reduces 11% of NOx emission and affects the other outputs, denoted with the 8.9% reduced BTE value compared with diesel fuel. Thus, the LPOC combination proved to operate well in the CRDI engine and produces lower NOx emissions than other LPO blends.

Experimental Study of the Influence of Moisture Content on the Mechanical Properties and Energy Storage Characteristics of Coal

Rock burst occurs frequently as coal mining depth goes deeper, which seriously impacts the safety production of underground coal mines. Coal seam water injection is a technique commonly used to prevent and control such accidents. Moisture content is a critical factor tightly related to rock burst; however, an in-depth insight is required to discover their relationship. In this study, the influence of moisture content on the mechanical properties of coal and rock burst tendency is explored via multiple measurement techniques: uniaxial compression test, cyclic loading/unloading test, and acoustic emission (AE) test. These tests were performed on coal samples using the MTS-816 rock mechanics servo testing machine and AE system. The testing results showed that with the increase in moisture content, the peak strength and elastic modulus of each coal sample are reduced while the peak strain increases. The duration of the elastic deformation phase in the complete stress-strain curves of coal samples is shortened. As the moisture content increases, the area of hysteretic loop and elastic energy index W ET of each coal sample are reduced, and the impact energy index K E is negatively correlated with the moisture content, whereas dynamic failure time is positively correlated with the moisture content, but this variation trend is gradually mitigated with the continuous increase of moisture content. The failure of the coal sample is accompanied by the sharp increase in the AE ring-down count, whose peak value lags behind the peak stress, and the ring-down count is still generated after the coal sample reached the peak stress. With the increase in moisture content, the failure mode of the coal sample is gradually inclined to tensile failure. The above test results manifested that the strength of the coal sample is weakened to some extent after holding moisture, the accumulative elastic energy is reduced in case of coal failure, and thus, coal and rock burst tendency can be alleviated. The study results can provide a theoretical reference for studying the fracture instability of moisture-bearing coal and prevention of coal and rock burst by the water injection technique.

Effect of relative humidity on water injection technique in downsized spark ignition engines

Combustion knock is a major barrier to achieving high thermal efficiency in spark ignition engines. Water injection was recently identified as a potential way of overcoming this barrier. To evaluate its general applicability, experiments were performed on a downsized three-cylinder spark ignition engine, varying the humidity of the intake air, the water injection timing, and the engine speed. The minimum quantity of injected water required to maintain a given load (and thus level of engine performance) was determined under each set of tested conditions. The knock-suppressing effects of water injection were found to be related to changes in the fuel–air mixture’s specific heat ratio (kappa) rather than evaporative cooling, and to therefore depend on the total quantity of water in the cylinder rather than the relative humidity per se. The total quantity of water in the cylinder was also shown to be a key determinant of advancement in combustion phasing and particulate emissions under various conditions.

Evaluating scale deposition and scale tendency of effluent water mix with seawater for compatible injection water

Water injection technique is contributing millions of oil barrels on a daily basis to the global oil supply; one of the challenges faced by such an important production method is scale buildup due to the different dissolved solids and high salinity of the injected water. For produced water or effluent water, pretreatment is a critical step before the injection process to reduce the risk of scale potential and well formation damage. One of the beneficial treatments of the effluent water is to be mixed in a compatible ratio with seawater, especially for those countries with easy access to seawater. Thus, the objective is to find a compatible mix ratio with seawater as one way of solving effluent water reuse without increasing the risk of scale and formation damage during water injection operation. In this study, effluent water samples were collected from different oilfield geographical locations in Kuwait, and then the samples were analyzed in the laboratory for their physical and chemical properties to select the most compatible one for mixing with seawater. The selected effluent water was then mixed with seawater in 1:1 ratio to evaluate the compatibility of the mix in terms of sulfate formation and scale tendency. The selected North field/seawater was tested under 75 ºC and 1000 PSi in an autoclave. The filtered precipitates were characterized by energy-dispersive spectroscopy (EDS) and scanning electronic microscope (SEM) micrographs. Further, the formations of sulfate were detected by X-ray diffraction (XRD). The OLI ScaleChem software was used to investigate the composition of mineral scales that may occur in the water mix at different ratios ranging from 0 to 100% to compare it with the actual water mix finding. In the effluent waters comparison part, North field water showed low pH (4.6) and alkalinity, as well as moderate TDS (190,000 MG/L). The main constituents of the scale deposited at the selected water mixing ratio were calcium sulfate CaSO4 and silicon oxide detected by XRD. However, the amount of barium sulfate was not presented in the precipitates indicating that all of it went in the liquid phase. The study concludes that at downhole conditions, the compatible mix of North Kuwait effluent water with seawater has high risk of barium sulfate in comparison with other common scale such as calcium sulfate, calcium carbonate and strontium sulfate (SrSO4). Also the study revealed that the prediction of different seawater ratios showed that at 70% seawater concentration, the barium sulfate concentration drops and consequently the scale risk reduced.

A MODIFIED WATER INJECTION TECHNIQUE TO IMPROVE OIL RECOVERY: MISHRIF CARBONATE RESERVOIRS IN SOUTHERN IRAQ OIL FIELDS, CASE STUDY

A modified water injection technique has organized by this study to improve oil recovery of the Mishrif reservoirs using polymerized alkaline surfactant water (PAS-Water) injection. It is planned to modify the existing water injection technology, first to control and balance the hazardous troublemaker reservoir facies of fifty-micron pore sizes with over 500 millidarcies permeability, along with the non-troublemaker types of less than twenty micron pore sizes with 45 to 100 millidarcies permeability. Second to control Mishrif reservoirs rock-wettability. Special core analysis under reservoir conditions of 2250 psi and 90 °C has carried out on tens of standard core plugs with heterogeneous buildup, using the proposed renewal water flooding mechanism. The technique assures early PAS-water injection to delay the water-breakthrough from 0.045 – 0.151 pore volumes water injected with 8 – 25% oil recovery, into 0.15 – 0.268 pore volumes water injected with 18 to 32% improved oil recovery. As well as, crude oil-in-water divertor injection after breakthrough, within 0.3 to oil0.65 – 0.85-pore volume of water injected to decrease water cut 1 four 0 to 15%. The overall progress of the PAS-water injection has achieved residual oil mobility of 65%, and upgraded the 35 – 50% oil recovery range by less than three pore volume water injected with 20 – 60% water cut, compared with the same oil recovery range by more than ten pore volume water injected with around 70% water cut. The ultimate oil recovery improved by this technique is from 70% via more than 20 pore volume water injected with over 95% water cut by usual water injection, to 85 – 90% via 6.4 pore volume water injected with over 90% water cut by the modified water injection. The technique succeeded to lower the end-point mobility ratio to 1.5 from above five by usual water injection. It is highly recommended to use ten micron mesh filter at the main injection site and four or five micron mesh filter at the injector sites; to avoid more than 80% of the suspended particles and save as much as possible the overall reservoir facies from permeability damage.

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.

Use of Water Injection Technique to Improve the Combustion Efficiency of the Spark-Ignition Engine: A Model Study

Use of Water Injection Technique to Improve the Combustion Efficiency of the Spark-Ignition Engine: A Model Study

Combustion analysis of hydrogen-diesel dual fuel engine with water injection technique

In this paper, the effect of direct diesel injection timing and engine speed on the performance and emissions of CI engine operating on RCCI (H2/diesel mixture) coupled with water injection have been numerically investigated and validated. The simulation have been carried out using GT-Power professional software. A single cylinder dual fuel compression ignition model has been built. The diesel fuel was injected directly to the cylinder. The hydrogen and water were injected to the engine intake manifold and engine port with constant mass flow rate and constant temperature for all engine speed. During the simulation the engine speed was varied from 1000 to 5000 rpm and the diesel injection timing was varied from (−5° to −25° CAD). In addition, the optimized diesel injection timing for specific engine operation parameters has also been performed.The results show that, for specific injection timing and constant hydrogen and water mass flow rate, the increase of engine speed results in an increase in the cylinder temperature, engine brake power, brake specific fuel consumption and NO emissions; but decreases brake thermal efficiency. Moreover, the analysis performed shows that, the advanced injection timing decreases the engine power, brake thermal efficiency and CO emissions; but increases NO emissions.

Method of moderate water injection and its application in ultra-low permeability oil reservoirs of Yanchang Oilfield, NW China

Abstract To explore the method of improving development effect and solving the problem of water breakthrough and water out for ultralow permeability fractured reservoirs, an indoor evaluation method of dynamic imbibition for fracture-matrix system was established taking the Chang 8 reservoir in southern Yanchang Oilfield as a research target. Key factors for the imbibition effect were obtained, an imbibition's rate expression was obtained, a model considering the double effects of imbibition-displacement was built and optimal injection and production parameters for the research area were obtained as well. The results show that an optimum displacement rate that maximizes the oil displacement efficiency exists in the water displacing oil process, and the optimal displacing rate becomes smaller as the permeability decreases. The imbibition displacement efficiency increases as the reservoir quality index and water wettability index of rock become bigger. But the larger the initial water saturation or oil-water viscosity ratio is, the smaller the imbibition displacement efficiency is. The optimal injection-production ratio for the Chang 8 reservoir of southern Yanchang Oilfield is 0.95, and the predicted recovery is 17.2% when the water cut is 95%, it is 2.9% higher than the recovery of conventional injection-production ratio 1.2. By using the moderate water injection technique based on the double effects of imbibition-displacement mechanism, the water injection development effect for the ultra-low permeability fractured reservoirs can be improved significantly.

The physics of CO2 transfer during carbonated water injection into oil reservoirs: From non-equilibrium core-scale physics to field-scale implication

CO2 can be dissolved into water to make carbonated water (CW). CW can be injected into oil reservoirs for enhanced oil recovery (EOR) and CO2 sequestration purposes. Carbonated water injection (CWI) technique is a cost-effective CO2 based injection strategy that needs less amount of CO2 as compared to other CO2-EOR techniques. We previously showed that for simulation of CWI coreflood experiments, the kinetics of CO2 transfer between the phases should be considered and we accordingly developed a non-equilibrium based two-phase compositional simulator. We also used the developed simulator to simulate some CWI coreflood experiments. This paper aims to explore the role of mass transfer during simulation of CWI process at field (large)-scale by analysing the data of core-scale simulations. To do so, the results of CWI core-scale simulations obtained from our non-equilibrium based simulator are benchmarked against the results from an equilibrium based simulator and a dimensionless number so-called equilibrium number (Ne) is introduced. It is shown that in a specific range of Ne values, the contact time of the oil and water phases inside the system is large enough that the CO2 can be distributed between the phases based on its equilibrium concentration. Contrary to core-scale simulation, it is concluded that mass transfer kinetics during large-scale simulation of CWI process is not important. Moreover, higher oil recovery factor and CO2 storage are predicted at large-scale (reservoir-scale) as compared to the core-scale's results. The findings of this paper can help to better understand the importance of mass transfer kinetics between the phases in porous media.

Effectiveness of injecting lower dose subcutaneous sterile water versus saline to relief labor back pain: Randomized controlled trial.

INTRODUCTIONThe aim of this study was to investigate the effect of a lower dose subcutaneous sterile water injection technique versus subcutaneous saline injection, on the relief of low-back pain for women during childbirth, and to explore the lasting effects of pain relief after administration (followed at 15, 30, 45, 90 and 120 minutes).METHODSA prospective randomized controlled single-blinded study was conducted, with trial registration (NCT02813330). Women received one-time injections (sterile water or saline) and the effectiveness was observed at 15, 30, 45, 90 and 120 minutes after the intervention.RESULTSThe intervention group had statistically significant pain reduction. Assessment of subsequent pain, followed at 30, 45, 90 and 120 minutes, reflected an increasing change with a statistically significant difference. The intervention group had more burning sensations than the control group with a statistically significant difference.CONCLUSIONSThe modified technique of double injections of subcutaneous ‘water/ saline’ resulted in significant relief of low-back pain during childbirth.