Abstract: The invention relates to a circulating mass dryer for drying wet sludge. According to the invention, the circulating mass dryer includes two adjacent circulating mass systems in heat exchange communication with one another, wherein the first circulating mass system is a sludge drying side and the second circulating mass system is a heat releasing side, and the first and the second circulating mass system each comprises at least one elongated riser (3, 16), and the riser (3) of the first circulating mass system and the riser (16) of the second circulating mass system are adjacent in such a way that a common heat exchange surface is formed therebetween. In addition, the invention relates to a corresponding method.

Abstract: The object of the invention is a method for enhancing the operation of a circulating mass reactor (1), which circulating mass reactor (1) comprises a fluidized-bed chamber (8) provided with a fluidized bed (108), means for separating fluidized material (80) from the flue gases, and a return conduit system (15, 16, 19) including at least one cooled return conduit (15, 16). In the method, for the combustion of fuel taking place in the circulation mass reactor (1) is provided a lower combustion chamber (89), which comprises a fluidized-bed chamber (8), and an upper combustion chamber (11) and a flow conduit (10) connecting them. The flow conduit (10), the means for separating the fluidized material (80) from the fuel gases and the return conduit system (15, 16, 19) are arranged to be located essentially between the lower combustion chamber (89) and the upper combustion chamber (11).

Abstract: The object of the invention is a method for enhancing the operation of a circulating mass reactor (1), which circulating mass reactor (1) comprises a fluidized-bed chamber (8) provided with a fluidized bed (108), means for separating fluidized material (80) from the flue gases, and a return conduit system (15, 16, 19) including at least one cooled return conduit (15, 16). In the method, for the combustion of fuel taking place in the circulation mass reactor (1) is provided a lower combustion chamber (89), which comprises a fluidized-bed chamber (8), and an upper combustion chamber (11) and a flow conduit (10) connecting them. The flow conduit (10), the means for separating the fluidized material (80) from the fuel gases and the return conduit system (15, 16, 19) are arranged to be located essentially between the lower combustion chamber (89) and the upper combustion chamber (11).