Liaohe Oilfield Research Articles

Optimized Design and Research on Technology Parameters of Concentric Dual-Tube Steam Injection Horizontal Well

The screen pipe completion is the predominated method for heavy oil horizontal well in Liaohe Oilfield, accounting for 83.4% of the total completions. General steam injection has been used for the horizontal wells, resulting in a better exploitation percentage in heel part but a poorer exploitation percentage beyond 1/3 of the distance from the tiptoe to heel in horizontal well. As the concentric dual-tube steam injection technique for horizontal well has just been developed in Liaohe Oilfield, the related supporting technique is not enough. In this paper, researchers consider achieving horizontal wells concentric dual-tube steam injection optimized design as main goal so that the physical model will be established, and also the calculation methods for pressure, the calculation models for quality, heat loss and tapered string parameters along the wellbore will be provided during the concentric dual-tube steam injection for horizontal wells.

Research and Application of KCL Drilling Fluid Technology

In ord to solve the hole collapse problem of mud shale in LiaoHe Oilfield,further research and improment of KCl drilling fluid was conducted.and promotion in mine house, two South Beach Sea and other regions, to prove that the strong anti-sloughing drilling fluid system capacity, accident low, Liaohe Oilfield meet the needs of sloughing shale.

The Application of High Temperature Foam Surface Active Agent Used in Heavy Oil Thermal Recovery

Heavy oil in Liaohe oilfield is buried in more than 1000 meters, and the steam injection temperature is around 350°C. Through the experiment on surfactant product, high temperature foam surface active agent was developed, which was based on high carbon chain alkyl benzene sulfonate or alkyl toluene sulfonate, and auxiliary solvent and stabilizer were added. High temperature foam surface active agent can meet the needs of steam foam profile control technology.

Injection-Production Parameters Optimization Research SAGD Production Stage

Steam assisted gravity drainage (SAGD) technology has been industrialized popularization and application in our country, according to the characteristics of Xing group I SAGD experimental zone in liaohe oilfield, SAGD production stage injection-production parameters such as the operating pressure, Sub - Cool control, steam injection rate, steam dryness, production factor are studied and selected.

Effective Application of Solid Expandable Tubular During the Enhancement of Heavy Oil Recovery in China, Lessons Learned and Experience Shared

As the traditional thermal recovery became less effective in exploring the heavy oil reservoirs, some newly developed techniques such as chemical flooding, SAGD and HDCS are demonstrating their advantage in the recovery process in China. However, the ever increasingly used new techniques often compromised severely the well integrity as the flow of extremely high temperature fluid or gas caused quick damage to casing, leaving the wellbore less reliable. This compromise requires urgently a workover strategy that would maximize the well’s life span and guarantee the effectiveness of new techniques. Solid expandable tubular (SET) was field-proven in casing patching activities, but its application in the heavy oil recovery has not been attempted due to severe temperature challenge. We made innovations on the traditional structure of SET and got valuable results. The tubular after expansion was integrated with the original casing as a whole and the rubber was removed in-between, the wellbore size was maintained utmost and the casing was further strengthened. Meanwhile the expansion cone was put outside the tubular which is a big step forward in SET structure. Indoors experiments demonstrated sound performance of the new structure in the simulative temperature of 350 ℃, the plan for the field application was optimized based on the lessons collected in this experiment. High temperature well applications by SET were carried out in Liaohe oilfield which is famous for its heavy oil resource in China, and the detailed process as well as the outcome were compared and analyzed, finally the conclusions were drawn as a result of the whole study. We expect our work will help expand this enabling technology to better facilitate the enhancement of heavy oil recovery and maintain solid well integrity during the heavy oil production. Key words : Solid expandable tubular; Heavy oil recovery; China

Experimental Study of Dehydration Effect of Crude Oil in Multi-purpose Station

Crude oil dehydration process in multi-purpose station is of great importance, in which there are a lot of confounding factors and parameters. In order to solve the dewatering difficulty in multi-purpose station of Liaohe Oilfield during operation, we designed a laboratory experiment of thermo-chemical setting dehydration, and analyze these factors impacting the liquid mixture separation of oil and water from the districts, including to liquid water content, dehydration temperature, PH value of crude oil solution, demulsifier dosing concentration, produced fluid composition. This research shows that: adjusting the technological parameters in a reasonable range, is both beneficial to dewatering and improving heavy oil dehydration effect, and of great significance of improving the downstream production standard. Key words : Heavy oil; Multi-purpose station; Crude oil emulsion; Demulsification

Prediction of thermophysical properties of saturated steam and wellbore heat losses in concentric dual-tubing steam injection wells

Concentric dual-tubing steam injection is important in the process of thermal recovery for heavy oils. This paper firstly presented a mathematical model to predict thermophysical properties of saturated steam (i.e. steam pressure, temperature and quality) and wellbore heat losses in CDTSIW (concentric dual-tubing steam injection wells). More importantly, a semi-analytical model for estimating pressure gradient for steam/water flow in annuli was developed. Then the mathematical model is solved using an iterative technique. Predicted results were compared with measured field data to verify the accuracy of the model. The results indicate that the direction of heat transfer between fluids in the integral joint tubing and in the annulus depends not only on wellhead injection conditions but on temperature drop in each tubing. In addition, the steam qualities in CDTSIW are significantly influenced by heat exchange between fluids in dual tubing, which can cause steam boiling or condensation. Moreover, the paper shows that to effectively reduce the wellbore heat losses and to ensure high bottomhole steam qualities in Well Xing 67 of Liaohe Oilfield, the thermal conductivity of insulation materials should be less than 0.7 W/(m K).

Application of Monitoring Data of Multi Point Temperature and Pressure in Regulation of SAGD Well Group

SAGD has been a major replacing technology in Liaohe Oilfield at the late stage of steam soaking and the scale is expanding gradually, How to monitor the SAGD horizontal production well effectively is the key problem in operating the SAGD well group, multi-point monitoring technology is adopted in Liaohe Oilfield to Monitor multi point temperature and pressure of production wells in the SAGD well group, Multi point measured data of temperature and pressure analysis method is obtained through typical examples analysis, and the important role of multi-point monitoring data is pointed out in regulation of SAGD well group.

Water Testing Technology Research and Application in Horizontal Well

Now, water testing in horizontal well is still a worldwide problem, has not yet been mature and reliable technology is widely used in oil fields. Liaohe oilfield test center after three years of scientific research, has made some progress, developed a set of suitable technology for water testing in Liaohe oilfield horizontal wells, and to apply this technology to the water testing in oil wells, a good test results have been achieved.

Effect of Dissolved Oxygen Content on Gelling Strength of Chromium Gel in Block Hai 1

Jinma company of Liaohe oilfield has carried out weak gel flooding in-depth in block Hai1 and achieved good effect. But in the process of profile and flooding, problems of gelation fluctuating and gelling rate declining seriously affected the implementation effect of the profile control and flooding project. It is researched that one of main factors affecting gelling effect of profile and flooding system is the dissolved oxygen. Aiming at this problem, this paper studies critical value affecting gelling in combination with the actual situation of polymer displacement in block Hai 1. The experimental results show that, content of dissolved oxygen affects both gelling strength and gelling time of weak gel in the way that when dissolved oxygen content is between 0mg/L and 3mg/L, low gelling strength and long gelling time are obtained, while in the range of 4mg/L-10mg/L, gelling effect is good. Two critical values are respective 1.5mg/L and 7mg/L.

Research and Application of Technology of Mobile Electric Ignition Technology for Fire Flood in Vertical Hole

In-Situ combustion is an important transformation mode for heavy oil development, and the key to its success is ignition in the reservoir, On the basis of investigation and research into some related techniques both at home and abroad, this paper presents the development of mobile electric igniter, technical string, down-hole monitoring system, putting-in and putting-out device; the integral outside diameter of the igniter is φ25.4mm; this paper forms the technique of mobile electric ignition for fire flood in vertical hole and introduces the technical principle. The field test results show that the maximum outlet air temperature of the igniter is 527°C when the steam injection rate is 6500Nm3/d; And that realizes high temperature igniting of mobile electric igniter for the first time. This technique will effectively reduce the operation cost of fire flood, and provides technical reserve for separate zone ignition in thick mass oil pool of Liaohe Oilfield.

The Scaling Preventable Measures of Multi-Effect Distillation Plants

The multi-effect distillation (MED) process is one of the oldest process in desalination of seawater. This technology has been used for water and heat recovery from the petroleum waste in Liaohe Oilfield. However, the scale formation is one of the main problems that encountered in the operation of different plants. The temperature of the first stage of the MED evaporation is higher than 138 °C. Therefore, both the scale inhibition and removal technologies should be adopted. The Belgard EV 2050 scale inhibitor produced by Ciba-Geigy is recommended to be used to inhibit the scale due to the excellent scale inhibiting performance. Scale removal technology also needs to be adopted regularly for device descaling in addition to the scale controlling technology. The sulfamic acid (concentration of 5% -10%) can be selected as the acid cleaning agent with a certain amount of inhibitor added.

Treatment of Oilfield Sewage by Thermal Distillation Technology

A large amount of waste heat is generated in the oil extraction process when using steam assisted gravity drainage (SAGD) technology. Thermal distillation technology is recommended to deal with the Liaohe Oilfield sewage. It not only can utilize the low-grade energy source, but also can recover the water to settle the water shortage problem. The principles and processes of multi-stage flash distillation (MSF), multi-effect distillation (MED) and vapor compression (VC) are introduced, and the tech-economic analysis is also made. It is found that it has significant advantage in heat and water recovery using the MED technology to deal with the Liaohe Oilfield sewage.

Preparation and Application of J-F Profile Control Agent

In Liaohe oilfield Xing 28 block before and during the alkali/polymer binary compound flooding process, there are heterogeneity contradictions on vertical and plane formation. In order to solve this contradiction, improve the utilization rate of oil displacement agent, J - F profile control agent was developed successfully, the profile control agent is not restricted by formation pH value and gel time, of good resistance to flushing, temperature tolerance and salt resistance. Through the field test, using J-F profile control agent the injection profile changed significantly and the injection pressure increased, a remarkable economic benefits and social benefits are gained.

Finite element analysis of deformation mechanism for porous materials under fluid–solid interaction

Deformation of underground rocks, also named rock creep, is treated as porous materials which usually results in many engineering problems, especially in petroleum engineering. However, it can be controlled by fluid–solid interaction in porous materials, and the deformation mechanism of underground rocks with fluid–solid interaction was analysed by finite element computing method. Specifically, an Iterative computing method and a computational procedure of two-way fluid–solid coupling are used to simulate deformation process until the fluid and solid solution variables are fully coupled. A typical application example was taken in Jinzhou oil production plant of Liaohe Oil Field Company, and a finite element model is built by combined application of parasolid and native modelling methods. According to the calculation results, deformation mechanism of underground rocks is proposed, and some advice is also presented.

Method of Secondary Logging Interpretation of Heterogeneous Reservoirs in the Huan 26 Block, Liaohe Huanxiling Oilfield

The reservoir units in Liaohe oilfield showed strong heterogeneities. A process of log normalization and a set of logging interpretation models appropriate to the reservoir bed characters of this section were established based on the first logging interpretation results and the core analysis. After normalization of all log curves, and according to the interpretation models that have been established, the secondary logging interpretation was applied in the study area and the interpretation models were proved to be feasible and reliable by the application of the first logging interpretation results and the core analysis. The method can not only provide instruction for further reserves calculation and geological modeling, but also be a foundation for numerical simulation.

Dynamic monitoring of water petroleum substance using HJ-1/CCD remote sensing data

The experiment data used in this paper include CDOM(Chromophoric dissolved organic matter) absorption coefficient, water apparent optical properties and petroleum pollution concentration, which were obtained in May 2008, August 2009 and June 2010 respectively at Liaohe Oilfield in Panjin city, Liaoning province of China. A model between CDOM absorption coefficient and petroleum pollution concentration was developed, and then was applied to eight HJ-1CCD remote sense images obtained from 2009 to 2011, to produce multi-period temporal and spatial distribution maps of petroleum concentration in costal waters. Based on these thematic maps, the dynamic monitoring of petroleum pollution concentration distribution was done. The results showed that (1)There was a decreasing trend of petroleum concentration from costal waters to open sea, which manifest itself as an approximately zonal distribution;(2) due to low precipitation in May and June every year, the concentration of petroleum keeps in a relatively high value state; (3) in September, the concentration of petroleum decreases dramatically as pre increases, most of the area below 0.29 mg/L; (4) compared with that in the same period, the concentration of petroleum in April 2010 is apparently higher than in April 2011, and among the images in September from 2009 to 2011,the highest concentration of petroleum appears in 2010, and the lowest in 2009.

Optimization of Development Mode during the Later Steam Huff and Puff in Heavy Oilfield

The M block in Liaohe Oilfield uses steam huff and puff coupled with water flooding, and it has entered the middle-later period of oilfield development. To keep stable yield, the development mode should be changed. Based on the geological characteristics in the M block, this paper puts forward two different ways: Horizontal well injects steam to steam drive; Horizontal well as product well when vertical well injects steam. Combined with practical data and using numerical simulation to analysis, the results show that: Horizontal Well injects steam to steam driving is the best way; the recovery percent is as high as 22.72%. This development mode will work no matter in the short run or getting the economic limit rate.

The Finite Element Analysis of Derrick Translation System in Vehicular Pressure Balance Workover Rig

Nowadays the workover rig is more often used in outdoor work, and the field environment is complicated and changeable.Therefore, it becomes extremely important to conduct a detailed analysis of stress of the workover rig derrick translational system.This paper takes Liaohe Oilfield new vehicular pressure balance workover rig derrick translation system as an example, a finite element analysis model is established to analyze the stress conditions of the derrick truck system.The result completely conforms to the actual requirements, thus verifying the rationality of the design and providing the basis for the optimization design of the translation system.

The Experimental Research on Combining Binary Compound Flooding and Profile Control Technology to Improve Recovery Efficiency

With the using of binary compound flooding in Jinzhou oil production plant of Liaohe Oilfield, problems like interwell interporosity flow and the unsatisfactory displacement effect occurs. The EOR method of combination of binary compound flooding and profile control technology has been adopted to solve these problems. The JSY crosslinking agent has been selected which has good compatibility with binary compound system by means of experiment of gel strength and gel time. And the formula system of binary compound flooding profile control which can improve the displacement effect of Jinzhou oil production plant has been formed after concentration optimization aim at improving oil recovery. The laboratory core plugging experiments show that the system of binary compound flooding profile control behaves better plugging effect and its plugging rate was greater than 94%. The parallel displacement experiments on low, medium and high permeability cores show that the oil recovery of binary compound flooding profile control system, which can improve the oil recovery more effectively, enhanced about 12% of oil recovery than binary compound flooding.