Dynamic Evaluation Methodology And Algorithm Implementation Of Steam Flooding Development

Today, with the constant development of the oil industry, the proportion of heavy oil resources in geological reserves is much larger, the methods of how to efficiently mine heavy oil resources underground have become the world’s oilman continuous research focus.In1952, Shell oil company took the lead oilfield test of steam flooding in California YorbaLinda oilfield, steam flooding development abroad has made significant achievements. At present abroad main steam flooding oil fields are American KemRiver oilfield, Belridge oilfield, Midway Sunset, oil fields, San Ardo oilfield, Indonesia Duri oil field, Venezuela Bare oilfield, Canada Cold Lake and Peace River oil field. In these countries, the daily output of steam flooding production at the beginning of2000accounts for their respective EOR ratio are55%in the United States,75%in Canada;94%in Indonesia. It seems that steam flooding technology has been applied widely by those heavy oil producer abroad, and achieved good effect.The steam drive technology in China began in the late1980s. In xinjiang oilfield and Liaohe oilfield as a base test application. Heavy oil reservoir of liaohe oilfield is characterized by deep buried depth over1000m, the main development of Qi40block of steam drive test works best. Steam flooding stage total steam injection is148.5x104t, total oil output is22.5×104t, phase gas oil ratio is0.15, the stage of recovery degree is of26.2%. The success of the Qi40block of steam flooding test for deep heavy oil steam flooding has laid a solid foundation in China and even in the world’s large-scale development.Thermal recovery technology as the main technical means of production development of heavy oil resources are fully applied in our country. In our country, most of the heavy oil block has experienced more coherence and cycle huff and puff development, as the results that continuously reduce production, recovery efficiency is declining, mining effect is poor. The application of steam flooding technology become the key way to solve this situation. For heavy oil steam drive technology for scale implementation, but the development of the urgent need to establish a set of evaluation system, expanding test guide steam drive technology. Correct understanding of heavy oil reservoir after steam stimulation condition, develop standard and evaluation index of heavy oil thermal recovery, establish a combination evaluation method, the mathematical model and numerical simulation become the key of analyzing the development effect and directing the practical production. This paper based on the analysis of steam drive steam flooding mechanism, structure of reservoir characteristics and technology condition, on the basis of mathematical thinking and mathematical methods to solve the steam drive implementation process of the key factors affecting development result, combined with the mathematical analysis model and an important parameter in production and development, the dynamic analysis of steam drive development in different stages of the development effect, direct steam drive late on. Reference the method of a large number of domestic and foreign research on steam drive theory, establish wellbore heat loss, pressure drop, steam dryness, the mathematical model of temperature and heating radius analytic steam drive thermal efficiency; Establish steam injection rate, injection volume and the analysis of the mathematical relationship between the degree of dry steam injection steam injection process; Analysis and selection of suitable for the calculation method of steam drive production; Group and single well injection-production parameters evaluation, establishing single well optimizing steam injection pressure, steam injection rate, steam quality evaluation method and the symmetry of the evaluation of the production factor.In order to establish an effective and practical thermal recovery of heavy oil evaluation system, it is necessary to according the production requirements to put forward a set of development index and evaluation standard, to establish a reasonable mathematical model for the evaluation method. This paper selects seven indicators to evaluate the steam flooding of heavy oil reservoir development, such as steam flooding development index, thermal efficiency, the steam cavity formation, development process, injection-production parameters, output prediction, and the single well well group. Against one of the main parameters to establish the most close to the reality and reasonable mathematical model, and gives detailed derivation process. And the application of the method of evaluation and Liaohe oilfield Qi40block65well group, comprehensive analysis and production indicators of evaluation of the well group, divided the development stage, at the scene under the contrast of production data and production effect, demonstrate the rationality of steam flooding of heavy oil development dynamic evaluation method.Qi40block is analyzed in the process of evaluation of the main problems in the development process and the main factors influencing the development effect, and targeted control measures are put forward. Measures for field application effect is good, have positive guidance. Finally concluded as well group effect degree is uneven, contradictions increasingly prominent. Steam flooding displacement clear direction, single, single direction steam breakthrough has become increasingly serious. Form a complete set of steam flooding technology can’t meet the needs of the development at present stage.