Apparatus and installations for the purification of flue gases and the production of carbon dioxide from flue gases; flue gas scrubbers for the cooling and the purification of flue gases, in particular direct contact coolers; flue gas scrubbers for the removal of acidic components from flue gas, in particular for the removal of sulphur dioxide, hydrogen chloride or hydrogen fluoride; flue gas scrubbers for the removal of solid particles or aerosols; flue gas filters for the removal of solid p...