In apparatus for cleaning the head-exchanging surfaces of the storage elements of rotary regenerative heat exchangers having at least one row of nozzles disposed beside one another, orientated substantially at a tangential direction and in a radially displaceable manner before an end face of a storage element in the interior of the heat exchanger, which nozzles direct the cleaning material, delivered to them from a source of cleaning material, in an aimed manner onto the storage element, wherein the nozzles (70, 72, 74, 76;
- 84, 86, 88) are provided on at least two radially spaced-apart nozzle heads (19;
- 17) on a tube arrangement (11;
- 13) extending substantially radially over one half of the end face of the storage element (1), and the tube arrangement (11;
- 13) guided in a sealed manner into the interior of the heat exchanger (1, 3, 5) is guided radially above the storage element (1) such as to be displaceable back and forth and is movable back and forth above the storage element (1) by a drive means,
- the improvement wherein:
- the tube arrangement carrying the nozzle heads (19;
- 17) comprises a double tube connected to the heat exchanger at a sealed entry and including first and second radial tubes (11, 13) connected via external movable connecting means to first and second stationary material lines (49;
- 51) delivering the cleaning material, each of said radially movable nozzle heads (19;
- 17) being divided into two laterally separated nozzle plates (69;
- 82), one of said nozzle plates carrying a first group of nozzles (70-76) and the other of said nozzle plates carrying a second group of nozzles (84-88), said first group of nozzles (70-76) communicating with said first radial tube (11) and said second group of nozzles (84-88) communicating with said second radial tube (13), said first group of nozzles (70-76) providing a different type of cleaning action from said second group of nozzles (84-88), wherein at least in the vicinity of the sealed entry into the interior of the head exchanger, said double tube has said second radial tube (13) and said first radial tube (11) substantially coaxially surrounding said second radial tube,
- a box-like collector (39) for cleaning material, said box-like collector being disposed between said movable connecting means and an outer end of the double tube (11;
- 13);
- and
- means for movably mounting said box-like collector comprising:
- a rail means (41) arranged for carrying said box-like collector (39) and on which said box-like collector (39) is movable in the longitudinal direction of said double tube (11;
- 13);
- and
- force transmitting means (33, 35) coupled to said box-like collector (39) for moving said box-like collector along said rail means (41).