Injection Pipeline Research Articles

Numerical investigation of corrosive gases absorption process by water injection in hydrogenation reaction effluent system

Abstract Water injection for absorbing corrosive gases NH3, HCl and H2S is a widely employed method to mitigate the risk of ammonium salt corrosion in the hydrogenation units. To ensure the efficient prevention of ammonium salt corrosion, a numerical model integrating the hydrodynamics of gas–liquid and the reaction of interphase mass transfer was built based on Euler–Lagrange method in this work. The flow and mass transfer characteristics of complex multi-component system in water injection pipeline were investigated, and the correlation between process operating conditions and gas removal performance was analyzed. The results reveal that the removal efficiencies of corrosive gases in pipeline are influenced by the characteristics of gas–liquid flow and mass transfer, with HCl showing higher removal efficiency compared to NH3 and H2S. Furthermore, the increasing flow rate of water injection, the reducing corrosive medium content and the decreasing droplet diameter have a positive impact on the removal efficiencies of corrosive gases, while the impact of gas-flow velocity on the removal efficiencies of corrosive gases primarily depends on the residence time of droplets. These results have important theoretical value and engineering guiding significance for intensifying the process of water injection in hydrogenation units.

Assessing sulfate-reducing bacteria influence on oilfield safety: Hydrogen sulfide emission and pipeline corrosion failure

With the further development of oilfield, excessive sulfate-reducing bacteria (SRB) has intensified odors and increased pipeline leakage incidents. Accurate predictive models of H2S emission and pipeline corrosion based on SRB content are essential for safety. This study analyzed the correlation between sulfide content and SRB content at different nodes in the injection-production system of Daqing Oilfield, and characterized the pipeline corrosion products using scanning electron microscopy (SEM), X-ray diffraction (XRD), and stereo microscope. Corrosion rates were investigated through 18 sets of orthogonal experiments, considering factors such as SRB, temperature, pH, liquid flow rate, CO2 partial pressure, and H2S partial pressure, and the main controlling factors of corrosion were identified. Finally, the risk models for H2S emission and corrosion rate based on SRB content were established under on-site operating conditions. The results show that a significantly positive correlated between SRB and sulfide content at different nodes, with the highest levels observed at the settling tank, indicating the highest risk of H2S emission. SRB contributed to corrosion in both water injection and oil collection pipelines, with more serious corrosion in the water injection pipeline. SRB and pH were identified as the main factors influencing corrosion rate. The H2S emission prediction model based on the correlation of SRB and sulfide was reliable, with an accuracy exceeding 90 % compared to the measured results. Additionally, the corrosion rate model for pipelines, related to SRB content, had an error of less than 7 %. To minimize risks, it is recommended to maintain a low risk environment in the injection-production system by sterilization and increasing the pH of water. This study has significant theoretical importance for ensuring the safe operation of injection-production systems.

Analysis of the hydrogen safety of the NPP with a VVER-1200/V-491 reactor in a severe beyond design based accident

The results of a computational analysis of possible modes of combustion of a hydrogen-air mixture in containment during the evolution of a severe beyond design basis accident (BDBA) with the COCOSYS code are presented. The containment of the NPP with a VVER-1200/V-491 reactor was selected as the object of study. BDBA with loss of coolant occurs due to a break of the injection pipeline of the pressurizer system (LOCA DN179) and the simultaneous failure of all active channels of the emergency core cooling system (ECCS). The calculated parameters of the thermodynamic state (pressure and temperature) of the gas mixture are given, and the values of the concentration distribution of hydrogen inside the containment are presented. After calculating the hydrogen distribution and mixing in all compartments of the containment, an evaluation was made of the flammability of the mixture and the potential for self-ignition in the containment by using a three-component Shapiro-Moffette diagram. It was concluded that in BDBA (LOCA DN179 with failure of active ECCS) detonation of the hydrogen-containing mixture is excluded, and deflagration is possible only in the emergency compartment of steam generators with a pipeline break. Thus, the hydrogen risk mitigation has been achieved in accordance with the standards established by the Belarusian regulator, provided that the localization safety systems are operational in the event of hydrogen deflagration. And the efficiency of the hydrogen removal system from the containment using catalytic recombination is considered sufficient for the considered BDBA.

Mixed transportation optimization model for oilfield water injection synergizing pipeline network and trucks

The water injection network is a common method in oil extraction processes, generally characterized by high energy consumption. Therefore, the adoption of scientifically sound and rational optimization schemes is crucial. However, due to the limited injection capacity of water injection station (WIS), when their supply is less than the demand of the injection wells, trucks are used for supplementary water injection. This paper introduces an oilfield water injection method under water injection pipeline and trucks coordination transport. An optimization model for oilfield water injection in this mixed transportation mode is established to address the supply-demand imbalance in the water injection network. The study uses a specific oilfield water injection system as a case study to validate the applicability of the mixed transportation water injection model (MTWI-Model) compared to the conventional water injection model (CWI-Model). The findings indicate that when only CWI-Model is used, the water volume from the injection station cannot meet the demands of the injection wells, leading to the cessation of some wells and potential overload of pumps in the station, thus affecting the normal operation of the water injection station and ultimately the oil recovery rate. Furthermore, the paper compares the optimization results of the mixed transportation model under two scenarios: fixed and non-fixed water intake points (namely MTWI-FP-Model and MTWI-NFP-Model). The results show that the mixed transportation mode with non-fixed water intake points is more economical, saving a daily cost of 632.28 Yuan/d compared to the fixed point scenario.

A numerical study on hydrogen blending in natural gas pipeline by a T-Pipe

In order to study the flow blending and transporting process of hydrogen that injects into the natural gas pipelines, a three-dimensional T-pipe blending model is established and the flow characteristics are investigated systematically by the large eddy simulation (LES). Firstly, the mathematical formulation of hydrogen-methane blending process is provided and the LES method is introduced and validated by a benchmark gas blending model having experimental data. Subsequently, the T-pipe blending model is presented, and the effects of key parameters, such as the velocity of main pipe, hydrogen blending ratio, diameter of hydrogen injection pipeline, diameter of main pipe and operating pressure on the hydrogen-methane blending process, are studied systematically. The results show that, under certain conditions, the gas mixture will be stratified downstream of the blending point, with hydrogen at the top of the pipeline and methane at the bottom of the pipeline. In the no-stratified scenario, the mixing distance increases at lower hydrogen mixing ratio and larger diameter of the hydrogen injection pipe or the main pipe. Finally, based on the numerical results, the underlying physics of the stratification phenomenon during the blending process are explored and an indicator for stratification is proposed using the ratio between the Reynolds numbers of the natural gas and hydrogen.

Vibrational Analysis and Optimization of a Water Injection Pipeline in a High-pressure Plunger Pump

Vibrational Analysis and Optimization of a Water Injection Pipeline in a High-pressure Plunger Pump

Research and Application of HSE Control System for High Consequence Area Water Injection Pipeline

In view of the fact that the safety management technology prevention and control capabilities are weak in the safety management technology such as long operating life, high pipeline operating pressure, large control area, difficulty in detecting abnormal phenomena, slow valve opening and closing speed, and difficulty in quickly handling emergencies in oilfields, the HSE control system of water injection pipelines in high consequence areas is developed and designed with the help of technical means such as Internet of Things and edge gateway computing, which realizes real-time monitoring of water injection pipeline pressure in high consequence areas, remote control of shut-off valves, timely elimination of hidden dangers, and timely control of dangerous situations. Purpose of expeditious disposal. This research project was tested in the field of a branch of a water injection line in a typical high-consequence area. The verification results show that the system has the functions of real-time monitoring of water injection pressure and remote control of shut-off valve, which is of great significance for improving the HSE technical defense system of oilfield and improving the ability of oilfield to deal with emergencies.

Compressibility of blends of diesel fuel with palm oil

The article presents the results of experimental studies to determine the compressibility of mixtures of diesel fuel with palm oil. To determine the compressibility of fuel mixtures in this work, we used a method based on measuring the speed of sound in the fuel in the injection pipeline. A description of a laboratory setup for measuring the speed of sound propagation in a mixed fuel is given, and the experimental procedure is outlined. The results obtained show that with an increase in the initial compression pressures and the density of fuel mixtures, which depends on the volumetric content of palm oil in them, the speed of sound increases, and the compressibility decreases. Formulas are presented that approximate the experimentally found dependences of compressibility on pressure and the proportion of palm oil in the mixed fuel. The results of the research can be used in modeling the fuel supply process of diesel engines operating on mixtures of diesel fuel and palm oil.

Causes and treatment of adhesive damage in polymer flooding injection pipeline

The viscosity of polymer liquid is an important parameter used in oilfield. Understanding the loss rule and regularity of polymer liquid will help to improve the distribution and water injection quality of polymer liquid and ensure the effective distribution of polymer liquid. According to the oil-water viscosity data of the previous polymer flooding fluid, it is found that the oil-water viscosity is within the range of 5%-20%, with an average of 9.8%. The reasons of single well pipeline viscosity are complex and varied, which are closely related to reducing substances, types and quantities of bacteria, fouling oil suspensions on the inner wall of pipeline, pipeline length and running time. Therefore, from the aspects of Fe2+, pipeline running time and so on, the influence factors and prevention methods of single well pipeline viscosity loss were studied, and the corresponding treatment measures were worked out, and good results were obtained.

2ZXS-2 哈密瓜移栽机的关键部件设计与试验

Aiming at the trouble of low survival rate of cantaloupe seedling in hyperthermia, drought and dry land in Turpan region of China, the existing transplanting machine is the key to mechanized and non-destructive transportation and planting of large plants of young tender melon seedlings, root water injection, and precise soil piling in planting holes，and other technical difficulties. The design of mulch film planting cantaloupe transplanter for laying pipes belts and membranes, watering and transplanting, which can complete rotary tillage, spreading drip irrigation belts, laying mulch and covering the soil around the membrane, transplanting pot seedlings on the membrane, and water injection at the bottom. This machine puts the water injection pipeline under the inner side of the transplanter, and through the multi-point linkage electric control, the seedling preservation water is injected into the bottom of the seedlings pot while the seedlings are transferred, which not only ensures the survival rate of the melon seedlings, but also an accurate piling of the planting hole is realized. The technology of transplanting with water and piled soil for planting holes effectively solved the technical problems of mechanized transplanting of cantaloupe under high temperature and arid climate conditions in Turpan. After the cantaloupe seedlings were transplanted in dry land, the probability of survival was more than 96.9% after seven point five hours of drip irrigation. Operating efficiency can reach 0.067 hectares per hour, eight times as much as manual transplanting. The speed of transplanting machine is about 1.1 m/s, the quality of transplanting rate was 93.26 percent. The operating standards of these transplanters meet the agronomic requirements for transplanting cantaloupe.

Effect of sulfate-reducing bacteria from salt scale of water flooding pipeline on corrosion behavior of X80 steel

As a means to enhance the recovery of oil reservoirs, waterflooding is widely employed in field development. However, because injected water contains solid impurities and incompatible characteristics, water injection pipelines often suffer from scaling and blocking. In addition, because these pipelines are typically buried in underground soil, microbial bacteria are derived from humid and oxygen-deficient environments, causing serious microbial corrosion on the basis of scaling corrosion. The objective of this study was to analyze the corrosion behavior under the combined effect of sulfate-reducing bacteria (SRB) and the scale layer (CaCO3) induced inside a water injection pipeline. With an X80 steel pipeline as the experimental material and an oilfield injected water simulation solution as the experimental medium, this study conducted weight-loss tests and electrochemical experiments. Combined with the experimental results, scanning electron microscopy, electrochemical impedance spectroscopy, element and phase analyses, and 3D corrosion morphology reconstruction technology were used to explore the changes and mechanism of corrosion behavior under the combined effect of CaCO3 scale layer and SRB in water injection pipelines used in oilfields. The study results showed that a nonuniformly distributed CaCO3 scale layer can provide sites for SRB metabolic activity and also serve as a channel for the exchange of corrosion ions. The corrosion rate of the water injection pipeline increased significantly under the combined effect of the CaCO3 scale layer and SRB, and pitting corrosion under the biofilm/scale layer was serious. In the presence of iron oxides, SRB could interact with CaCO3, causing microbial dissimilation and reduction of iron oxides, forming a loose FeS product film, and accelerating the corrosion process of steel pipelines.

The thermal-fluid-solid coupling effect in nuclear reactor vessel with direct vessel injection

Different from conventional cold leg safety injection, a newly designed reactor type CAP1400 directly connects the injection pipeline of the emergency cooling system with the pressure vessel. However, these structures have been found to potentially have adverse effects on the pressure vessel. This paper employs both physical experiment and numerical analysis to investigate the dynamic oscillating load and the structural response. A 1:9 scale model is adopted for the experimental section. The uncertainty of the measurement quantities is within 3%. The CFD code and the FEM code are used to simulate the transient fluid flow and solid structure deformation, respectively. The sequential coupling method is used for the thermal-fluid-solid coupling calculation. The overall error of the calculation is within ±10%. The result shows that the fluctuation of the physical quantity near the wall is caused by turbulence eddy and thermal mixing, and the flow, heat transfer and structural deformation near the wall of the pressure vessel are closely coupled. The effect of the turbulence eddy can be seen within the entire range of frequency measured, while that of the thermal mixing can be seen only within the low frequency range. The influence law of the loop flow ratio, the flow rate of the downcomer and the loop temperature difference in the structural response are obtained. Through the research of this paper, the law of interaction between the thermal-fluid load and the structural response under direct safety injection is more deeply understood. Thus, it provides a design reference for the safety of reactors.

Corrosion mechanism of high temperature and O2 content in steamed CO2/O2/SO2 system and failure behavior of 20G steel on steam-injection pipelines

The corrosion mechanism and failure behavior of 20 G steel in steamed CO2/O2/SO2 environment (7.8 MPa, 100–301 °C) are studied. The surface characterization technology is adopted to analyze the corrosion rate and the microscopic morphology of corrosion product film, where the corrosive influencing factors are determined. The influence of temperature on the film formation kinetics is greater than that of cathodic reaction thermodynamics, wherein the corrosion product film has good performance for anti-corrosion. The interaction between H+ and Cl- leads to the degradation of mechanical properties. The residual-life evaluation model is proposed to recommend the reinspection period of the steam injection pipeline.

Life cycle cost analysis of CO2 compression processes coupled with a cryogenic distillation unit for purifying high-CO2 natural gas

Novel compression processes coupled with a cryogenic distillation unit are designed in this study to purify high-CO2 natural gas or biogas before injection into the reservoir. Four different designs are evaluated to achieve the required injection pressure and minimize both the capital and operation costs. Depending on the pressure–temperature pathway for the compression of the top and bottom products of the distillation unit, the energy and equipment costs are quantified using process simulation models and economic analysis tools, which are integrated with the flow simulation model to determine the required injection pressure. This holistic approach of integrating the compression process and injection pipeline is efficient for optimizing the process design and operation variables. The results suggest that liquefying the top product followed by mixing with the bottom product is the most cost-effective method, as it eliminates costly compressors and simplifies the process configuration. In addition to the life cycle cost analysis of the process, the sudden release of CO2 from the vessel is also studied experimentally. The results show that releasing gaseous CO2 through the valve induces the formation of solid CO2 inside the vessel before complete removal of CO2 from the vessel, thus requiring a controlled release strategy to avoid solid CO2 formation inside the vessel and through the valve.

Оценка надежности функционирования главной водоотливной установки кимберлитового рудника

One of the reasons for the breakthrough of the pit bowl, and, accordingly, the flooding of the kimberlite mine Mir could be the deterioration of the drainage system from the mine. The slowdown in the process of pumping mine water from the Mir mine to the daytime surface is explained by the fact that the actual total productivity of its two main drainage installations was not designed to pump out the water inflow, which is much higher than normal. After the emergency that resulted in the death of people, and subsequently the conservation of the mine for an indefinite period, a detailed study of ways to improve the reliability of the operation of the main drainage installations of operating kimberlite mines became one of the areas of scientific research of PJSC ALROSA (PJSC). To date, the most flooded domestic kimberlite mine is the Udachny mine. The pumping equipment of its main dewatering plant is characterized by a rather low operational reliability. The article is devoted to assessing the reliability of the operation of the main drainage plant in the Udachny kimberlite mine for the period 2016–2021. It is established that the time spent by the pumping equipment of the main drainage plant for pumping out normal and maximum water inflows increased by 2 and 2.5 times, respectively, in this period, which negatively affected the reliability of its operation in terms of compliance with the safety requirements. To ensure long-term reliable and efficient operation of the main dewatering plant of the Udachny mine, it is required to lay another injection pipeline staves, as well as to drill catchment mine workings near the quarry, in the areas where the main volume of quarry water is formed.

Experimental Research on Cationic Surfactants in the Drag Reduction of Water Injection Pipeline

Summary To achieve the throughput increase and drag reduction of the water injection pipeline for offshore oil fields, this paper takes the cationic surfactant solution as the research object and explores the feasibility of applying the additive drag reduction technology to the water injection pipelines through the rheological test and drag reduction simulation device. The experimental results show that the cetyltrimethylammonium chloride (CTAC) selected initially has excellent thixotropy, and the viscosity recovery rate within 300 seconds can reach more than 97%. In addition, CTAC/NaSal (sodium salicylate) solution has strong oil resistance and salt tolerance. As the oil concentration increases from 0 to 6,000 ppm, the viscosity only decreases by 8.24%; as the salt concentration increases from 0 to 6,000 ppm, the maximum viscosity growth rate is 87.08%. Furthermore, the CTAC/NaSal has good temperature resistance, which enhances with the increase of concentration. The recommended concentration of drag reducer is 400 ppm, and the maximum drag reduction rate, throughput increase rate, pressure drop reduction rate is 74.19, 76.76, and 67.99%, respectively. Therefore, the CTAC/NaSal solution has broad application prospects in the drag reduction of water injection pipelines.

A Method for Optimising Pump Configuration and Operation in Oilfield Water Injection Network

Some oilfields in China encounter operating problems on water injection pipeline networks. Due to the unreasonable planning of the pipeline, water cannot be transported to the end of the pipeline and injected into the wells. Also, a large amount of water is repeated transported. This paper aims to deal with the above issues by proposing a method of using pipeline pumps to pressurise the water injection pipeline network, which can improve the water supply capacity of the pipeline network, and reduce the energy consumption of water injection. The pipeline pump has the characteristics of convenient installation, compact structure, and wide application range. To effectively utilise the pipeline pump in the water injection network, a pipeline pump boosting optimisation model is developed, taking the lowest cost of the pump and operating energy consumption of the water injection system as the objective function, and considering the constraints of water injection, pipeline network hydraulics and pump operation. An oilfield in China is studied as an example, the results show that the proposed model can optimise the pump installation position and operations. The operating cost was reduced by 184 k CNY, and the total annual cost was saved by 154 k CNY. The maximum water injection increment can reach 4,700 m3/d, which improves the water supply capacity of the water injection pipe network, and the needs of oilfield water injection planning can be satisfied.

The research on the operation mode and parameter selection method of large-scale water injection pipeline network

Due to the complexity of the large-scale water injection pipe network system and the difficulty of manual analysis, it is impossible to guarantee the optimal operation mode scheme selected. At present, there are still gaps in the research on the judgment of its optimal operation mode. Through the calculation and evaluation of a large amount of water injection system data, the selection method of the optimal operation mode of the water injection system is determined, and it is found that the selection of the optimal operation mode is closely related to the pressure distribution characteristics of the individual wells of the entire water injection system, and five discriminant rules for the optimal operation mode of the water injection system are formed based on these characteristics; the mathematical model for determining the mode and the optimal method of operating parameters is given, and the pipeline network simulation system automatically generates the pipe network topology diagram; the optimal operation mode of the water injection system is developed; Intelligent judgment software can modify its operating parameters according to needs, change operating modes, easily simulate the energy consumption in various modes of operation, adjust and find the optimal operation plan of the water injection pipe network. Application examples show that the judgment rules of the optimal operation mode of the water injection system and the optimization method of operating parameters can be used as an effective means for selecting the optimal operation plan for a large-scale water injection pipeline network.

Research on Partial Pressure of Oilfield Water Injection Pipeline Network System Based on Fuzzy Logic

Aiming at the middle and late stages of oilfield development, the retirement of water injection wells in old areas of the water injection system, the increase of water injection wells in new areas, and the incorporation of tertiary injection wells into the subsequent water flooding have caused great changes in the layout of the water injection pipeline network, causing the mixed injection of high and low pressure wells, a fuzzy logic method is proposed to divide the pressure of the water injection pipeline network, establishing a partial pressure reasoning model, setting the fuzzy domain and reasoning rules, and finally realize the division of high and low pressure areas of a large number of water injection wells. aking an oilfield water injection pipe network system as an example, the effectiveness of the method is proved through Matlab simulation and application research.

Research on Optimization of Flow Field of Denitration System of 600MW Unit and Modification of Fine Ammonia Injection

Aiming at the uneven distribution of flow field in the denitration system of coal-fired power plant boilers, poor mixing of ammonia and nitrogen, increased ammonia escape, and easy blockage of the air preheater, a flow field optimization and transformation plan was proposed through numerical simulation and added in the flue of the denitration system. Equipped with baffles and static mixers, modified the ammonia injection pipeline in zones, implemented ammonia injection total control and grid balance automatic adjustment control. After the transformation of precise ammonia injection for denitrification, the NOx emission of the unit is stably controlled at 40 mg/Nm3, the steady-state deviation value and other indicators are better than the acceptance standard, and the air preheater differential pressure is effectively controlled.