NOVELTY - A microbial film bed comprises cavity (1) and film bed (2) set inside cavity in which cavity is long tubular material, film bed is set in long tube middle part, film bed upper surface long tubular material side wall is set with flange or screw thread connection exit port (3), film bed lower surface long tubular material side wall is set with flange or screw thread connection inlet port (4) and screw thread connection hole (6) with valve (5), screw thread connection hole is located inside long tubular material side wall, and valve is located outside long tubular material side wall.    USE - A microbial film bed (claimed).    ADVANTAGE - Microbial film bed is low in cost, convenient to manufacture and use, and adaptable to anaerobic and aerobic film bed use and size, properties, and quantity of sewage.    DETAILED DESCRIPTION - A microbial film bed comprises cavity (1) and film bed (2) set inside cavity in which cavity is long tubular material, film bed is set in long tube middle part, film bed upper surface long tubular material side wall is set with flange or screw thread connection exit port (3), film bed lower surface long tubular material side wall is set with flange or screw thread connection inlet port (4) and screw thread connection hole (6) with valve (5), screw thread connection hole is located inside long tubular material side wall, valve is located outside long tubular material side wall, long tubular material upper port through screw thread or flange (12) is provided with discharge tube (7) upper cover (8), long tubular material lower port through screw thread or flange (14) is connected with sewage drain hole (9) lower cover (10), and sewage drain hole is set with drain valve (11).    DESCRIPTION OF DRAWING(S) - The drawing shows a structural schematic diagram of a microbial film bed.    Cavity (1)    Film bed (2)    Flange or screw thread connection exit port (3)    Flange or screw thread connection inlet port (4)    Valve (5)    Screw thread connection hole (6)    Discharge tube (7)    Upper cover (8)    Sewage drain hole (9)    Lower cover (10)    Drain valve (11)    Flange (12, 14)