木质素磺酸-栲胶接枝共聚物钻井液降粘剂

LIGNOSULFONATE/TANNIN REACTION PRODUCT AS THINNER FOR DRILLING FLUIDS

木质素磺酸-栲胶接枝共聚物XL-I是以木质素磺酸钙、栲胶和甲醛为原料制得的钻井液降粘剂。本文评定了XL-I的降粘能力,考察了XL-I的抗温抗盐性能,介绍了该稀释剂的现场应用情况。结果表明,XL-I是良好的淡水泥浆降粘剂,抗Ca^(2+)能力略强于FCLS,在NaCl含量高于2％的泥浆中的稀释能力比FCLS略差。

Calcium lignosulfonate is reacted with FeSO_4 at the presence of H_2SO_4 and, after the precipitated CaSO_4 having been removed, is further reacted with tannin extract and formaldehyde to give the end product, XL-I, as mud thinner. The laboratory results show that XL-I is comparative to FCLS in performance in bentonite muds however, XL-I is slightly more tolerent to Ca^(2+)and FCLS-more thermally resistant(>120℃)and slightly more effective in muds containing more than 2% NaCl. Field tests on XL-I instead of FCLS in drilling several wells (including directional one) are successful both in technological and economical aspects; furthermore, XL-I is advantaged over FCLS in gypseous strata.