Production process for manufacturing ash brick from fly ash

The invention belongs to the technical field of ash brick manufacturing, and particularly relates to a fly ash manufactured ash brick, which is composed of the following raw materials by weight: 62-70% of fly ash, 8-16% of quick lime, 3-6% of gypsum powder, 8-10% of coal cinder, 6-8% of water granulated slag, and 10-12% of sandstone. The grey brick is prepared by the following production steps: step S1, putting the raw materials into a dry powder stirrer according to a weight ratio, stirring for 5-8 minutes, and outputting for later use; s2, a certain amount of the mixed raw materials are taken and put into a mixing stirrer, water is injected, and monitoring is conducted through a water content detector in the injection process till the water content reaches 13%-15%. According to the invention, the gypsum powder prepared from 40-60% of snowflake gypsum and 40-60% of fiber gypsum is used for replacing a traditional gypsum material, so that the hydration reaction speed in the autoclaved fly ash is effectively i