It has been proved that it is economical and feasible to eliminate educt alkali from coarse sodium tungstate with electrodialysis method of negative ion (1) selective membrane.

一价阴离子选择膜电渗析法从粗钨酸中脱除游离碱是经济可的。

The reasons forming abnormal formation pressure mainly includes digenesis, thermogenesis, biochemical action, tectonic action, dialysis, and fluid density difference action.

形成异常地层压力的要有成岩作用、热力作用、生化作用、构造作用、渗析及流体密度差异作用等。