In the film above, we show how to solve this problem. Various unloading of hoppers into hoppers with tippers with the DustControl system installed without the aid of filters. Note that, even though the dust separates from the product, it does not come out through the hopper grate, depositing the dust along with the product. The DustControl system is not a flaps system. 

DustControl consists of modules that cover the entire hopper area beneath the grate. These modules are 40 to 50 cm deep and feature chutes that slightly reduce the speed of the product entering the hopper; the chutes are kept full of product so that air displaced from the hopper must pass through the column of product within them. As it passes through the module, the dust-laden air loses velocity and can no longer carry the dust, which remains with the product. The air exits the module clean. It is the most effective dust control method! It requires no filters; however, for hoppers requiring a higher level of air cleaning—such as those used with truck dumpers, where the volume of dust separating from the product during unloading is significantly higher—Wings can attach a bag filter to create negative pressure and draw in dust located above the grate. We recommend installing the mechanical DustControl system; if greater dust control is needed, the filter can be added later, as its installation does not require modifying the DustControl unit. Source: fonte: https://www.portosenavios.com.br/noticias/portos-e-logistica/rumo-e-caramuru-alimentos-anunciam-terminal-da-norte-sul-em-sao-simao-goFonte: https://valor.globo.com/empresas/noticia/2020/07/22/rumo-firma-parceria-com-caramuru-em-go.ghtml