Roof-fully-contacted roadway-type dense cemented filling system and roof-fully-contacted roadway-type dense cemented filling method

The invention discloses a full roof-contacted roadway type compact cemented filling system and method, the filling system comprises a slurry conveying system, a gangue conveying system and a jet filling system, the slurry conveying system is used for preparing mixed slurry, and the slurry is conveyed to the jet filling system in an underground pumping mode; the gangue conveying system conveys gangue to the underground to the jet filling system in a low-pressure air conveying mode; and then full mixing of the gangue and the slurry in the filling branch roadway in the air is achieved by controlling the jet filling system, fixed-point quantitative accurate filling is conducted, the filling effect is effectively guaranteed, and the filling roof-contacted rate and the filling body compactness are greatly improved. Meanwhile, the filling system realizes circulating operation of'spaced branch roadway coal output and step-by-step filling replacement ', two working procedures of coal mining and filling are operated in