The effects of using surfactant solutions while diamond drilling in amygdaloidal basalt of the Upper Michigan Copper Mining District were investigated. Nonionic, anionic, and cationic surfactant solutions, all biodegradable, were tested with size ax surface-set bits mounted on a drill instrumented for continuous recording of thrust, rotational speed, and torque levels. Water flow and penetration rates were also recorded. A drilling study was carried out, testing two rotational speed levels, two diamond bit grade levels, and four flushing agents (including water as a control). All surfactant solutions showed a 20- to 50-pct increase in solids content over that of water alone. Since flushing rates were constant, these increases in solids content agree well with the penetration rate changes. The diamonds were recovered from each bit of matrix dissolution, and bit wear was measured in terms of total loss of weight. Flushing with surfactant solutions showed a savings in bit wear in most cases.
Trans. Soc. Min. Eng., AIME, V. 258, No. 3, Sept. 1975, PP. 185-190