A Study Of Biodiesel-in-water Spotting Fluid

Pipe-sticking is a common accident in the process of drilling.Compared with other kinds of pipe-sticking,differential pressure sticking(also known as adhesion sticking)happens more frequently and causes bigger damage.When differential pressure sticking occurs,people usually use spotting fluids to deal with it.Spotting fluids can be divided into oil-based type and water-based type.Oil-based spotting fluids used to be very popular all over the world.However,since the 1980s,with the increasingly strict environmental protection laws and regulations,oil-based spotting fluids have been restricted.There are two solutions to this problem:one is to reduce the pollution of oil-based spotting fluids and the other is to develop efficient water-based spotting fluids.This article uses the environmental friendly biodiesel as the base oil and develops a new kind of biodiesel-in-water spotting fluid by optimizing the additives such as emulsifier,flocculant,penetrant and lubricant.The experimental results indicate that the spotting fluid has a good unfreezing performance,has good lubricity and can maintain stable performance under 120?.It can resist 5%sodium chloride and 5%calcium chloride.It will cause pollution to drilling fluids so isolation fluids are also necessary.The density can be adjusted to 1.5 g/cm~3to maintain good unfreezing performance and good heat stability.The biodegradation performance is better than that of diesel-based spotting fluids.The performance of the biodiesel-in-water spotting fluid accords with the industry standard and can greatly reduce the pollution to the environment.It has a good prospect of development and application.