Graphene additive for drilling fluids

Rice University and Houston-based M-I SWACO, the world’s largest producer of drilling fluids for the petrochemical industry, aim to develop a graphene additive that will improve the productivity of wells.

Rice chemistry professor James Tour’s lab will work with M-I SWACO’s researchers to optimise the effectiveness of nanoscale graphene additives to drilling fluids, also known as muds, in a two-year $450,000 (£275,780) effort.

Water or oil-based muds are typically forced downhole through a drill to keep the drillhead clean and to remove cuttings as the fluid streams back up toward the surface. But the fluids themselves can clog pores in the shaft through which oil should flow.

The nanoscaled graphene additive would be forced by the fluid’s own pressure to form a thin filter cake on the shaft wall preventing muds from clogging the pores.

When the fluids are removed along with the drill head, the formation pressure (the pressure of the oil or gas inside the ground) would force the filter cake out through the pores and into the shaft. ’When you release the hydrostatic pressure and pull the drill bit out, there’s much more pressure inside the rock than in the hole,’ Tour said. ’The filter blows out and the oil flows.’

James Bruton, M-I SWACO’s vice-president for research and engineering, said the cost of drilling fluids can reach $200 to $300 per barrel, and a well in the Gulf of Mexico might require more than 20,000 barrels to drill. ’It’s not a cheap undertaking for our customers, so the performance of the fluids is paramount,’ he added.

While the company’s current focus is on drilling muds, Bruton said future research would focus on using graphene in completion fluids and other drilling products. ’The ideas for using nanotechnologies are endless,’ he added.