天然气水合物钻探低温低密度水泥浆体系优选试验

Optimization Test of Low-temperature and Low-density Cementing Slurry System for Natural Gas Hydrate Drilling

摘要:

针对天然气水合物钻探对固井水泥浆的特殊要求，经过大量试验，优选出一种新型低温低密度水泥浆体系：100%G级油井水泥+15%漂珠+10%～15%微硅+8%超细矿渣+1%消泡剂+0.5%降失水剂+2.5%分散剂+2%硅烷偶联剂+5.6%～6%偏硅酸钠+8%～8.5%氯化钙+0.3%三乙醇胺+1%氯化钠（水固比0.7）。该水泥浆体系在低温条件下的密度、稠化时间、抗压强度、流变性和泌水量均可满足天然气水合物钻探固井要求。

Abstract:

In view of the special requirements for cementing slurry in natural gas hydrate drilling, a new low-temperature and low-density cementing slurry formula was obtained with a number of experiments, the composition is 100% class-G oil well cement + 15% floating beads + 10%～15% micro silicon + 8% superfine slag + 1% defoaming agent + 0.5% fluid loss additive + 2.5% dispersant + 2% silane coupling agent + 5.6%～6% sodium metasilicate anhydrous + 8%～8.5% calcium chloride + 0.3% triethanolamine + 1% sodium chloride with 70% water-solid ratio. The slurry system can meet the cementing requirements of natural gas hydrate drilling in density, thickening time, compressive strength, rheology and bleeding at low temperature.