Injection Pressure Research Articles

Abstract It is a new field to improve oil recovery by reducing the viscosity of thin oil in low permeability reservoir, which has a breakthrough significance for the development of low permeability oilfield. But, the oil increase effect of viscosity reducer (VR) solution on thin oil lacks the experimental data and theory support. The viscosity of ground degassed crude oil from the thin oil reservoir is 26.4 mPa s at 72°C. The feasibility of the application of VR solution in thin oil reservoir was analyzed through the experiment and test of viscosity reducing ability, percolation capacity, and displacement effect of VR solution. The oil–water ratio is 5:5, the VR concentration ( C VR ) of oil–water dispersion (OWD) solution is 0.1%, and the viscosity reduction rate of VR solution reaches 92.4%. The maximum instantaneous injection pressure ( P max ) of the VR solution injected with the C VR of 0.1% is the lowest, which is 6.60 MPa, the P max decreases by 0.83 MPa than the P max in the basic water flooding experiment, the injection pressure in stable stage ( P min ) decreases by 0.80 MPa. When the bound water saturation ( s wi ) ({s}_{\text{wi}}) of core is 41.1%, the VR solution is directly injected before water flooding, from the initial stage of water flooding, the water content ( f w ) ({f}_{\text{w}}) at the producing end tends to rise more slowly than that at the producing end of water flooding, the final recovery rate ( E R,final ) is the highest, 42.5%, the residual oil saturation is only 33.9%. The decrease in P max and the increase in E R,final indicate that the injection of VR solution can improve the percolation capacity of crude oil, and the method of reducing thin oil viscosity can be applied to the development of special permeable thin oil fields.

In light of the urgent need to reduce greenhouse gas emissions, hydrogen has emerged as a promising alternative fuel for compression ignition engines. Considering the challenges of onboard hydrogen storage and transportation, micro hydrogen addition in marine diesel engines is a viable transitional fuel strategy. This study employs an externally heated constant volume combustion chamber (CVCC) to experimentally investigate hydrogen-diesel combustion under simulated top dead center (TDC) conditions. High-speed photography was utilized to capture the ignition and combustion processes across six injection strategies, systematically varying three key parameters: hydrogen fraction (1.5%–3% vol.), injection pressure (60–120 MPa), and fuel mass (11.27–21.51 mg). The results show that higher injection pressures advance ignition timing (IT) by improving atomization, but excessive pressure (120 MPa) causes spray-wall impingement, reducing combustion efficiency and soot production. Hydrogen addition exhibits a non-linear effect on IT – 1.5% H 2 delays ignition due to oxygen displacement, while 3% H 2 advances IT because hydrogen’s lower heat capacity enhances local temperatures. The 90 MPa condition demonstrates the largest flame area and highest heat release rate (HRR), indicating optimal combustion performance. Increased injection mass prolongs ignition delay and suppresses flame luminosity due to deteriorated air-fuel mixture quality. Hydrogen addition shows a linear influence on combustion intensity, with higher concentrations leading to stronger combustion intensity.

Hydraulic fracturing is a technique employed to weaken rock formations during hard rock excavation. This study aims to investigate the impact of hydraulic fracturing on crack propagation in rock walls and its subsequent effect on the load borne by roadheaders during the cutting of pre-cracked rock. A three-dimensional model for the crack growth process in rock walls under hydraulic fracturing is developed using the CFD-DEM (Computational Fluid Dynamics–Discrete Element Method) two-way fluid–structure coupling approach. The results indicate that crack propagation under hydraulic fracturing occurs in four distinct phases: the initiation of the main crack, the further development of the main crack, the fine cracking phase, and the retardation of the main crack with the subsequent expansion of secondary cracks. The study analyzes the influence of pore size and water injection pressure on crack growth. It is observed that an increase in pore size and injection pressure within a certain range results in a nonlinear increase in crack propagation. Specifically, when the hydraulic fracturing aperture expands from 85 mm to 100 mm, the number of fracture bonds increases by 56.2%. Similarly, as water injection pressure rises from 25 MPa to 40 MPa, the number of broken bonds increases by 153.9%. The force exerted on rock with pre-existing cracks is found to be 9.05% lower compared to unfractured rock, with the average forces in the Z and Y directions reduced by 11.46% and 7.2%, respectively. However, the average force in the X direction increases by 5.49%. These findings provide a valuable reference for optimizing hydraulic fracturing procedures in hard rock excavation.

Dynamic covalent carbon dot-based emulsifiers: A novel strategy for smart Pickering emulsions and enhanced heavy oil recovery in ultra-low permeability reservoirs.

Experimental study on the effects of injection pressure and injection timing on combustion and emissions in a direct-injection hydrogen engine

Efficient coalbed methane (CBM) recovery combined with carbon dioxide (CO2) sequestration is a promising strategy for sustainable energy production and greenhouse gas mitigation. However, the molecular mechanisms controlling pressure-dependent CH4 displacement by CO2 in coal nanopores remain insufficiently understood. In this study, molecular dynamics simulations were conducted to investigate CO2-driven CH4 recovery in a slit-pore coal model under driving pressures of 15, 20, and 25 Mpa. The simulations quantitatively captured the competitive adsorption, diffusion, and migration behaviors of CH4, CO2, and water, providing insights into how pressure influences enhanced coalbed methane (ECBM) recovery at the nanoscale. The results show that as the pressure increases from 15 to 25 Mpa, the mean residence time of CH4 on the coal surface decreases from 0.0104 ns to 0.0087 ns (a 16% reduction), reflecting accelerated molecular mobility. The CH4–CO2 radial distribution function peak height rises from 2.20 to 3.67, indicating strengthened competitive adsorption and interaction between the two gases. Correspondingly, the number of CO2 molecules entering the CH4 region grows from 214 to 268, demonstrating higher invasion efficiency at elevated pressures. These quantitative findings illustrate a clear shift from capillary-controlled desorption at low pressure to pressure-driven convection at higher pressures. The results provide molecular-level evidence for optimizing CO2 injection pressure to improve CBM recovery efficiency and CO2 storage capacity.

Calcium hydroxide is commonly used as a root canal disinfectant due to its high alkalinity and biocompatibility. However, excessive injection pressure may cause extrusion beyond the root apex, leading to complications such as nerve or vascular injury. This report showed a case of a 58-year-old woman who developed cutaneous necro-sis and sensory disturbance in the left midface and nasal alar region following endodontic treatment on the left maxillary second molar. Computed tomographic imaging revealed calcified occlusion of the posterior superior alveolar artery. The patient was treated with debridement, stromal vascular fraction injection, and split-thickness skin graft. This case demonstrates a rare but serious complication, known as Nicolau syndrome, resulting from intra-arterial injection of calcium hydroxide. Clinicians should be aware of this potential risk and exercise cau-tion during delivery of intracanal medicaments, especially in vascular-rich anatomical regions.

Volume fracturing is a pivotal technology for exploiting coalbed methane in “three-low, one-high” reservoirs, though water retention often limits effectiveness. This research establishes a multi-phase flow–thermal coupling model integrating fluid dynamics, mass transfer, and heat transport to simulate thermal nitrogen injection into a three-level fracture network. The study examines multi-phase flow evolution and thermal response under varying injection conditions. Results reveal a three-stage displacement process: initial breakthrough through dominant channels, followed by mixed network flow, and finally stabilized gas propagation. Higher injection pressure significantly expands gas coverage and reduces residual water, while low pressure promotes water trapping. The temperature field evolution, mainly controlled by pressure, shows the most pronounced change in the main fractures. Flow behavior is hierarchically structured: primary fractures exhibit stepwise decline, secondary fractures display strong fluctuations, and tertiary fractures face initiation constraints. Increasing injection pressure enhances driving force, moderates flow decay in primary fractures, reduces instability in secondary ones, and facilitates activation of tertiary fractures. This process activates complex fracture networks and delays productivity decline, providing a theoretical foundation for post-fracturing water removal and enhanced permeability strategies.

Abstract In this experimental analysis, the impacts of altering the injection nozzle geometry on the performance parameters of a compression ignition (CI) engine were explored. The injection nozzle geometry of the standard engine with three holes of 0.24 mm diameter was replaced by a 6‐hole injector having 0.20 mm diameter. The modified engine was tested by a blend of 20 volume per cent of jatropha biodiesel (JOME20) in diesel. Considering the small size of the injector orifice, the injection pressure was raised to 240 bar from the standard pressure, and the injection timing was adjusted to 21° before Top Dead Center (bTDC) from the normal. The test findings revealed that the modified engine showed an enhancement in “Brake Specific Fuel Consumption (BSFC)” and “Brake Thermal Efficiency (BTE).” Notable improvements in the decrease of emissions have been observed. However, the enhanced fuel‐air mixing and high combustion temperature increased the oxides of nitrogen (NOx) emissions. The modification of the injection nozzle geometry showed improvements in BSFC, BTE, and a reduction in emissions, but with a trade‐off of increased NOx emissions, highlighting the need for further optimization.

The growing environmental challenges and the rapid depletion of global fossil fuel reserves have driven the urgent need to explore alternative energy sources. In present work, an experimental investigation evaluated the stability of ethanol-diesel blends using jatropha methyl ester (JME) as a co-solvent, alongside engine performance and emissions at varying injection pressures and timings. Stability tests revealed that ethanol cannot blend with diesel without additives, requiring at least 4% JME for one-day stability, with E10B10D80 (10% ethanol, 10% JME, and 80% diesel by volume) blends remaining stable above 10°C. Optimal injection parameters were identified as 2.0 × 10⁷ Pa pressure and 17° before top dead centre (BTDC) under different loads. JME proved effective as an additive, though its cost was higher than diesel, suggesting its long-term viability as fossil fuel resources diminish. Fuel consumption increased due to ethanol's lower calorific value, while thermal efficiency improved at low loads but decreased near full load. Emission analysis indicated that carbon monoxide (CO) emissions were lower at loads above half but higher at lower loads compared to pure diesel. Hydrocarbon (HC) emissions consistently rose with the blend, while a reduction in the nitrogen oxides (NOx) emissions was observed at relatively lower load but increased near full load, showing no consistent trend. The study highlights the potential of JME as a biofuel addi-tive, with its economic feasibility expected to improve as reliance on fossil fuels declines.

In this study, the thermal and structural behavior of battery module components produced from polymer-based composites was systematically evaluated using coupled Moldflow 2016 and ANSYS Fluent 2024 simulations. Three thermoplastics—metal-flake-reinforced PC+ABS (Polycarbonate/Acrylonitrile Butadiene Styrene), carbon-fiber-reinforced PEEK (Polyether Ether Ketone), and hybrid mineral-filled PP (Polypropylene)—were investigated as alternatives to conventional aluminum components. Moldflow simulations enabled the assessment of injection molding performance by determining injection pressure, volumetric shrinkage, warpage, residual stress, flow front temperature, and part weight. PEEK exhibited the best dimensional stability, with minimal warpage and shrinkage, while PP showed significant thermomechanical distortion, indicating poor resistance to thermally induced deformation. For thermal management, steady-state simulations were performed on a 1P3S pouch cell battery configuration using the NTGK/DCIR model under a constant heat load of 190 W. Material properties, including temperature-dependent thermal conductivity, density, and specific heat capacity, were defined based on validated databases. The results revealed that temperature distribution and Joule heat generation were strongly influenced by thermal conductivity. While aluminum exhibited the most favorable thermal dissipation, PC+ABS closely matched its electrical performance, with only a 1.3% lower average current magnitude. In contrast, PEEK and PP generated higher cell core temperatures (up to 20 K) due to limited heat conduction, although they had comparable current magnitudes imposed by the energy-conserving model. Overall, the findings indicate that reinforced thermoplastics, particularly PC+ABS, can serve as lightweight and cost-effective alternatives to aluminum in mid-range battery modules, providing similar electrical performance and thermal losses within acceptable limits.

The numerical reservoir simulation is a valuable tool to enhance heavy oil recovery by assessing different production strategies (like SAGD and CSS) and operational scenarios. While numerous studies have developed complex models, a systematic review identifying the most critical parameters for achieving accurate production forecasts is lacking. In this work, diverse studies have been reviewed regarding the numerical models of steam injection technologies by examining various parameters (reservoir properties and operating conditions) employed and their impact on the results obtained. Additionally, the effect of using kinetic models in simulations, as well as the modeling of solvent and catalyst injection, is discussed. The outcomes highlight that oil recovery for steam injection methods requires effective steam chamber management and an understanding of geomechanical changes due to the significant role of thermal convection on energy transfer and oil displacement. Increasing steam injection pressures can enhance energy efficiency and reduce emissions, but controlling the gases generated during the reaction poses difficulties. The gas formation within the reservoir in simulations is crucial to prevent overestimating oil production and improving precision. This can be achieved using simple kinetic models, but it is essential to incorporate gas–water solubilities to mimic actual gas emissions and avoid gas buildup. Crucially, our synthesis of the literature demonstrates that incorporating gas–water solubilities and kinetic models for H2S production can improve the prediction accuracy of gas trends by up to 20% compared to oversimplified models. Enhanced recovery methods (adding solvent and catalyst injection) provide advantages compared with conventional steam injection methods. However, suitable interaction models between oil components and solid particles are needed to improve steam displacement, decrease water production, and enhance recovery in certain circumstances. The use of complex reaction schemes in numerical modeling remarkably enhances the prediction of experimental reservoir data.

ABSTRACT The vortex tube (VT) is a device known for separating a compressed gas stream into hot and cold fractions. This study numerically investigates its dual potential for thermal separation and particulate matter (PM) removal. Using computational fluid dynamics, the effects of key design parameters and operating conditions on separation performance are analyzed for uniflow and counterflow vortex tubes. The investigated variables include tube diameter, inlet pressure, particle size (0.05 to 10 µm), and gas injection angle. The thermal analysis reveals a strong dependence of temperature separation (ΔT) on inlet pressure and diameter, with combinations of low pressure and large diameters yielding the highest ΔT, in the range of 60 to 70°C. The PM analysis shows that efficiency is governed by a coupled set of variables. Particle size is the dominant factor, with particles larger than 1 µm achieving over 99% removal efficiency. Inlet pressure has a diameter dependent effect; its increase significantly reduces efficiency in large diameter tubes but has a negligible impact in smaller tubes. A larger gas injection angle monotonically increases PM separation by strengthening tangential momentum. Coordinated selection of diameter, inlet pressure, and injection angle enables application specific tuning for simultaneous energy and particulate separation.

Abstract. Induced microseismicity has been detected in the Decatur CO2 sequestration area, providing critical constraints on the stress state at the reservoir. We invert the full stress tensor with two subsets of source mechanisms from the induced microseismic events. To achieve this, we incorporate additional information on the vertical stress gradient and instantaneous shut-in pressure (ISIP) measured in the area. Additionally, our results demonstrate that constraining the intermediate stress tensor to a vertical orientation is essential to achieve a consistent stress inversion. The inverted stress is then used to estimate the minimum activation pressure required to trigger seismicity on fault planes identified by the source mechanisms. The comparison of the minimum activation pressure with injection pressure indicates one of three possibilities: the ISIP pressures are significantly lower than predicted (approximately 28–29 MPa), the maximum horizontal principal stress is extremely high (exceeding 120 MPa), or the coefficient of friction is significantly lower than 0.6 on a large number of activated faults. Our analysis also shows that poorly constrained source mechanisms do not lead to reasonable stress constraint estimates, even when considering alternative input parameters such as ISIP and vertical stress. We conclude that induced microseismicity can effectively be used to estimate the stress field when source mechanisms are also well constrained. For future CO2 sequestration projects, measuring and constraining ISIP pressure and maximum horizontal stress in the reservoir will ensure that more accurate estimates of stress state from moment tensor inversions can be obtained for improved prediction of the long-term reservoir response to injection.

Di-tert-butyl peroxide and Ethyl-hexyl nitrate are efficient cetane-improving additives that result in better engine characteristics. This research focuses on studying the effect of cetane-enhancing additives with novel Ceiba pentandra biodiesel blend (B20) in the CI engine with a modified piston-top shape at an advanced injection timing of 27° BTDC (optimum FIP) and higher injection pressure of 260 bar to improve the engine characteristics. The addition of EHN at the concentration of 1.5%, raised the BTE, CP, and HRR by 7%, 4% and 1% respectively. Alongside the BSFC, CO, HC, and smoke are reduced nearly by 5%. Whereas, the addition of DTBP results in further 1 to 2% additional improvement in CI engine characteristics than EHN. With DTBP the BTE, CP, and HRR were increased to 8%, 5%, and 1.2% with the reduction in BSFC, CO, HC, and smoke by 6% as compared to B20. RSM optimization results also confirmed that the DTBP at 1.5% concentration at full load was the optimum one with a desirability function of 0.987. The cetane-enhancer’s additions to this novel BD at optimum FIP pave the way for superior combustion characteristics.

The development of tight sandstone gas reservoirs in the XUJIAHE Formation of western Sichuan faces critical challenges due to extreme reservoir conditions, including burial depths exceeding 4500 m, abnormal pore pressures (pressure gradient > 1.8 MPa/100 m), high breakdown pressures (> 90 MPa), elevated temperatures (> 120 °C), and ultralow permeability (< 0.1 mD). Conventional fracturing technologies exhibit low success rates (< 40%) and inadequate proppant placement efficiency (< 50%) under these conditions, severely limiting commercial gas production. This study presents an integrated fracturing strategy combining three novel approaches to address these operational and geological constraints. First, a high-density potassium formate brine system (1.5–1.6 g/cm³) reduced the bottomhole fracture pressure gradient to 0.0326 MPa/m through hydrostatic compensation, achieving a 21.83 MPa reduction in surface pump pressure compared to conventional fluids. Second, a hybrid fracturing design combining low-viscosity slickwater (3–5 mPa·s) and high-concentration cross-linked gel (80–120 mPa·s) simultaneously enhanced fracture complexity (Fracture Complexity Index > 2.5) and conductivity (> 100 Darcy), achieving a fivefold improvement in proppant transport capacity (600 kg/m³). Third, gelled acid pre-treatment (15% HCl system) dissolved calcareous interlayers (CaCO₃ >70%), reducing injection pressure by 14.83 MPa and increasing proppant migration efficiency by 30% in challenging Xu 4 intervals. Field implementation demonstrated breakthrough performance: fracturing success rates improved to 82%, with average post-fracture gas production reaching 2.7 × 10⁴ m³/d—a 210% increase over conventional methods. These innovations tight gas stimulation by synergistically addressing high-stress environments, fracture network complexity, and lithological heterogeneity, providing a replicable framework for deep unconventional reservoirs.

Carbon Capture, Utilization, and Storage has proven to be a core process for cutting greenhouse gas emissions, along with improving hydrocarbon recovery from oil and gas reservoirs. But existing challenges lie with the optimization of the capture efficiency, minimization of energy penalties, and ensuring secure long-term storage. This research formulates a holistic system that integrates machine learning (ML) techniques with advanced geomodeling techniques to propel the CCUS processes in the capture, transportation, and subsurface storage stages. Information was collected from various sources, such as industrial post-combustion capture plants, laboratory experiments, Enhanced Oil Recovery (EOR) field operations, public databases, and process simulators like Aspen Plus and HYSYS. Quality inputs were generated by applying rigorous preprocessing methods, i.e., data cleaning, feature selection, normalization, and dimension reduction. Machine learning models supervised by Linear Regression, Decision Trees, Random Forests, and Artificial Neural Networks (ANN) were trained to forecast energy consumption, CO₂ capture capacity, and storage behavior at different operation conditions. System parameter optimization involving solvent flow rates, injection pressures, and reservoir geometries was carried out using Genetic Algorithms (GA), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Simulated Annealing, and Sequential Quadratic Programming (SQP). Outcomes reveal that ANN yielded the best prediction performance (R² = 0.93, RMSE = 0.21) compared to Random Forests (R² = 0.88) and Decision Trees (R² = 0.79). Multi-objective optimization further showed that there exists a tradeoff between CO₂ capture efficiency and oil recovery when injection pressure and energy for solvent regeneration are concurrently optimized. Geomodeling analysis, through pore-scale simulations of metal-organic frameworks (MOFs) and correlation heatmaps, also confirmed that pore diameter and surface area are significant factors affecting adsorption capacity. At the same time, chemical composition is very weakly associated with selectivity. This study demonstrates how hybrid ML-geo modeling techniques can facilitate CCUS deployment by providing precise predictions, optimizing approaches, and enhancing the understanding of reservoir-scale dynamics. The results help formulate cost-effective, energy-efficient, and environmentally benign CCUS operations with implications for the upscaling of the technology in oil and gas operations and larger climate-mitigation measures.

ABSTRACT China’s rapid urbanization has amplified both the complexity of urban fire hazards and the demand for sustainable public safety solutions. Conventional fire extinguishing agents, however, suffer from inefficient performance and environmental pollution, underscoring the critical need for high-efficiency and eco-friendly alternatives. In this study, eight kinds of dry water (DW) were prepared by gel structure strengthening and gradient magnesium hydroxide modification. The effects of composition, particle size and pressure on the fire extinguishing performance were systematically analyzed, and the optimal injection pressure of the modified DW was determined. The results show that Mg(OH)₂-Gel-DW-B has the best overall performance, the outflow rate is 3.71 mL/s, the bulk density is 0.452 g/mL, and the particle size is mostly less than 300 μm. The gel structure makes the particle damage rate <12% under 1.4MPa pressure; The fire extinguishing efficiency of 200–400 μm particles is significantly higher than that of fine/coarse particles. Mg(OH)₂-Gel-DW-B cooling rate is 20.5% and 35.5% higher than ABC/BC dry powder. When the pressure increases from 1.0MPa and 1.2MPa to 1.4MPa, the Mg(OH)₂-Gel-DW-B damage rate increases by 96.06% and 62.39%, and the cooling rate decreases by 20% and 16.36%. Combined with the powder diffusion time difference <1s, the optimal injection pressure is determined to be 1.0 ~ 1.2MPa. The research provides the key theoretical support for the engineering application of environmental protection fire extinguishing agent.

In response to the problems encountered during the pressure-driven oil recovery process in low-permeability oil reservoirs, such as slow pressure transmission, poor liquid supply, vulnerability of the reservoir to damage, and difficulties in injection and production, in order to achieve the goal of high-quality water injection development, based on the theories of rock mechanics and seepage mechanics, combined with large-scale physical model experiments, acoustic emission crack monitoring, and microscopic scanning technology, an oil reservoir and fracture model was established to conduct a feasibility analysis of pressure-driven assisted pressure reduction and enhanced injection, and it was successfully applied in the exploration and development practice of the Shengli Oilfield. The research shows the following: (1) During the pressure-driven process, the distribution of the fracture network system is relatively limited. In the early stages of the process, there will be minor fractures, but they do not communicate or activate effectively. The improvement of physical properties and pore-throat structure is negligible. As the injection flow rate increases, the effective fracture network system begins to be established, and the range of fluid coverage begins to expand. With the progress of the pressure-driven process, the hydraulic fractures gradually extend, the number of activated original fractures gradually increases, the communication area between hydraulic fractures and original fractures gradually increases, and the reservoir modification effect gradually improves. (2) Based on the compression cracking experiment of large object molds, it is concluded that generating effective micro-cracks and activating them to form efficient diversion channels is the key to pressure flooding injection. Combining the mechanical characteristics of the rock in the target layer to precisely control the injection speed and injection pressure can maximize the fracture network, thereby improving the reservoir to achieve the purpose of pressure reduction and injection increase. (3) Different pressure flooding injection parameters were set for the low-permeability oil reservoirs in the study area to simulate the fracture network expansion. Finally, it was concluded that the optimal injection speed for fracture expansion was 1.2 m3/min and the optimal total injection volume was 20,000 m3. Through research, the mechanism of pressure-driven injection and the extent of reservoir modification caused by this pressure-driven process have been enhanced in terms of understanding.

Low-permeabilityreservoirs are plagued by persistenthybrid organic–inorganicblockages in associated water injection wells (or pipelines), particularlyunder harsh environmental conditions. In northern Shaanxi, China,water injection wells exhibit chronic high-pressure under-injection(>10 MPa), a critical issue linked to unresolved scaling and organicresidue accumulation. Conventional chemical treatments fail in subzerowinters due to reagent freezing and inefficient dual-phase targeting.Here, we developed a staged acid-oxygen synergistic system (LTDS)integrating sulfamic acid (inorganic scale dissolution), ammoniumpersulfate (radical-driven polymer oxidation), and alkyl polyglycosidesurfactants, augmented by an antifreeze additive (YangtzeU-TRA). Multimodalcharacterizationelemental analyzer (EA), X-ray diffractometer(XRD), Fourier transform infrared spectrometer (FTIR), and inductivelycoupled plasma optical emission spectrometer (ICP-OES)confirmedthe formation of hybrid blockages. Specifically, the blockages consistof inorganic phases dominated by calcium carbonate (CaCO3, 40.8 wt %) and iron­(III) hydroxide (Fe­(OH)3, 1.3 wt%), alongside organic components (20 wt %) that are identified asoxygen-rich polymers (characterized by the presence of carboxyl [−COOH]and amide [−CONH2] functional groups via FTIR analysis).The LTDS system achieved ≥85% dissolution within 1 h and ≥90%within 12 h at 40 °C. Crucially, LTDS retained fluidity after48 h at −20 °C (no coagulation), addressing winter operationalfailures. The field test results of 3 typical wells all showed a sustainedpressure reduction effect: post-treatment injection pressure stabilizedat 2 MPa (vs pretreatment >10 MPa), with 100% single-operationsuccessand 6 month stability. This study provides a solution for the dual-targetdissolution of complex blockages in low-permeability reservoirs, whichhas direct implications for energy security and sustainable hydrocarbonrecovery.