The Chuandong North Sea Carbonate Rocks High-sulfur Strata Safe And Efficient Drilling Fluids

Sea facies carbonate rock with high sulfur content in the northeast of Sichuan is complicated, often appears complex conditions such as spewing, leaking, collapsing, blocking and so on during the process of welldrilling. Analyzed geology engineering character of local region and developed researches of rheological properties, filtration building capacity and anti- contamination, lubricity of drilling fluid and anti-high temperature of stability etc through looking up to a great deal of domestic and abroad relevant technology and related data of the northeast of Sichuan, the drilling fluid system which is suitable for gas store of sea facies carbonate rock with high sourness in the northeast of Sichuan was formed----FHJJ polysulfonate drilling fluids system, whose anti-high temperature is 180℃,controllable density is 2.30g/cm~3.A series of countermeasure of drilling fluids technology was rendered by research according to the complicated conditions at local district. The mechanism of borehole wall was analyzed, appropriate density of drilling fluid was rendered and FHJJ polysulfonate drilling fluids system with strong ability of sealing and block and strong inhibition at aspects of borehole wall lost stability; according to different geological conditions different measure of precaution and solution was rendered, a few kind of new-style material blocking leak up was researched and different blocking leak up craft was worked out at aspects of leakage proof and blocking leak up; at aspects of prevented sulfureted hydrogen, various removed sulfur agent was appraised, and selected removed sulfur agent matched well to FHJJ polysulfonate drilling fluid, and a set of technique of prevented sulfureted hydrogen was formed.Field testing certificate, these drilling fluids techonogise have been gone on well appling.