Process for preparing water glass from silicon micropowder by using wet method

The invention provides a process for preparing water glass from silicon micropowder by using the wet method, belonging to the technical field of production of water glass. The process comprises the following steps: analyzing the content of SiO2 in silicon micropowder; mixing silicon micropowder and liquid alkali according to a mol ratio of 0.9-1.8:1; delivering obtained mixed liquor into a liquidphase reaction vessel under agitation; allowing steam to enter into the reaction vessel to heat the mixed liquor; carrying out a dwell reaction at a temperature of 70 to 220 DEG C for 0.5 to 6 h so as to prepare mixed liquor of water glass; discharging the mixed liquor of water glass out from the reaction vessel; adjusting the temperature of the mixed liquor of water glass to 50 to 95 DEG C in a feed liquid buffer tank; carrying out plate and frame pressurized filtering to obtain a filtrate which is water glass with a modulus of 1.80 to 3.20. The invention has the following advantages: since the water glass is prepared by using dust in the ferrosilicon alloy industry as a raw material and employing the characteristic that the reaction between amorphous SiO2 in silicon micropowder and alkali liquid has high activity, high conversion efficiency is obtained, the process is simple, the problem of dust pollution in the ferrosilicon alloy industry is overcome, and good economic benefits andsocial benefits are achieved.