Spreading system and method for producing a spreading material mat in the course of the production of material plates

Spreading system (1) for producing at least part of a spreading material mat (80) at least partially by means of wind scattering， with at least one first spreading head (2) for spreading a material flow (11) fed in a metered manner onto a forming belt (70) arranged below the spreading head (2) ; wherein the scattering head (2) comprises a wind scattering chamber (20) which has on one transverse side (3) an at least partially gas-permeable wall (31) which is equipped with a blower device (30) for introducing a gas stream (32) into the wind scattering chamber (20) is connected， wherein the spreading head (2) has at least one distribution device (40) below the gas flow (32) for distributing the material flow (11) onto the forming belt (70)， the distribution device (40) having an extension beginning in the wind scattering chamber (20) and extending beyond the wall (31)， the distribution device (40) being formed by a roller bed (41) made of scattering rollers (42) which are driven on the gas flow side in a direction of rotation (R) counter to the gas flow (32)， The distribution device (40) has a first section (401) for distributing at least some of the fine material portions (111) in the material flow (11) and a second section (402) for distributing the coarse material portions (112) in the material flow (11) onto the forming belt ( 70) and wherein in the wind scattering chamber (20) behind the wall (31) in the gas stream (32) at least one sieve (21， 22， 23) for at least partially separating the coarse material portion (112) from the fine material portion (111) in the material stream (11) and is arranged to transfer the shares to the different sections (401， 402) of the distribution device (40).