The Research Of Effective Development Fashion For Ultra-low Permeability Reservoir

With the healthy and stable development of the economy,the demand for crude oil is increasing at the speed of 5%-6% per year.But the ultra-low permeability accounts for 10% of the geological reserves of developed oil fild,and occupy half of the proven but untapped reserve on land.This urgent needs to carry on effective exploitation to the ultra-low permeability reservoir,satisfies the oil demand of country.At the same time, the rising oil price in recent years creates the economic feasibility for ultra-low permeability reservoir development.This paper researches ultra-low permeability reservoir development technologies both at home and abroad.Analyzes the well spacing and the well pattern density relations, as well as technical well spacing and economical well spacing computational method,thus the analysis method of rational well spacing through the technical well spacing and the economical well spacing computation has determined.And through numerical simulation researching for row well pattern,five-spot pattern,reverse nine-spot pattern,skewed four-spot injection pattern and reverse seven-spot patten,determining the well-pattern type that suits the ultra-low permeability by the water-cut and recovery alternation.Base on the research of rational well spacing and well-pattern, elaborating the waterflooding recovery feature,existing problems and influence factors,studing on advanced and cyclic water injection by using numerical simulation method and analysing it's influencing factor.Simultaneously,by using numerical simulation method,studying the carbon dioxide flooding and nitrogen flooding,the consideration influencing factor includes gas injection occasion,injection rate,injection mode,gas-water ratio,slug size and so on.Finally,through the comprehensive comparison to the water fooding and gas flooding, summarizing and analyzing the effective development fashion that suits the ultra-low permeability reservoir.