VERFAHREN UND VORRICHTUNG ZUR REINIGUNG VON GAS

Method and apparatus for circulation of sand for a sand filter for cleaning of gases, in which a number of filter modules arranged in a filter housing (1) is supplied with sand from a number of sand silos (2, 3). Sand and dust are periodically blown off the filter modules down in a {bottom funnel} in the filter housing (1) and subsequently led by a rotary valve (4) to a separator (5) where the sand is separated from the dust. The sand falls down into a sand conveyor (6) which transports the sand back to the sand silos (2, 3) in a sand loop (7) when the sand conveyor (6) is full. The sand is weighed in the sand conveyor (6) before it is led by the sand loop (7) to the silos (2, 3). This step is repeated until the bottom cone in the filter housing is empty. Net sand flow in the loop is calculated and sand refilled to or drained from the sand silos (2, 3) accordingly.