地层碱化处理中矿物碱溶规律研究

STUDIES ON DISSOLUTION OF ROCK MINERALS IN ALKALINE SOLUTIONS AND ALKALINE CONSUMPTION

研究了几种主要造岩矿物的碱溶规律。通过静态浸泡后上层清液中Ｓｉ、Ａｌ和ＯＨ－含量的测定，得出了固液比、浸泡时间、碱浓度、浸泡温度、碱类型等单一因素对不同矿物碱溶过程影响的规律。研究结果表明，延长浸泡时间、提高碱浓度、升高反应温度有利于矿物溶解；强碱促进矿物溶解；碱化处理的适宜碱剂为ＫＯＨ。

The reactions of alkalis, NaOH in most cases, in aqueous solutions with some rock minerals are studied by determining Si, Al, and OH - concentrations in the alkaline solutions and by X ray diffractography of the minerals. According to the amount of dissolution the minerals are arranged in order: montmorillonite>kaolinite>illite>ortholase>quartz>chlorite and the alkalis in order: NaOH>KOH>Na 2CO 3>NaHCO 3>Na 2O·3.56SiO 2. The reactions mineral/alkali proceed in two steps: fast ion exchange and dissolving out, the later may be accompanied by transformation of species or creation of novel minerals. In general, the more the amout of dissolution, the more the alkaline consumption. KOH appears to be the best alkali and the high temperature and low permeability reservoirs proper formations for alkaline treatments to be performed satisfactorily.