Recycling and harmless treatment technology of waste drilling fluid for Xianglouye-1 well

Abstract:

To implement the concept of green exploration， a recycling and harmless treatment system was developed for the 800 m3 waste drilling fluid generated during the construction of Xianglouye-1 well. The waste fluid is collected in a waste mud tank. After coarse solid particles are preliminarily separated by a desander， qualified slurry is returned to the drilling circulation system. Unqualified slurry is subjected to gel-breaking treatment by adding polyaluminium chloride （PAC） and anionic polyacrylamide （PAM）， followed by solid-liquid separation with filter press to produce mud cake and clean water. The clean water can be recycled or discharged up to standard， and the solid phase can be used for road construction or safely landfilled. Field application results show that 400 m3 waste drilling fluid and 200 m3 clean water of the whole well were recycled by this system， saving more than 160000 RMB in material cost directly. Zero pollutant emission was achieved， which provides a feasible technical scheme for environmental treatment of drilling fluid in shale gas exploration.