DE102009011673A1 - Dryer for all types of dry material, is provided with drum body and process air return duct housing surrounded with outer isolation - Google Patents

Abstract

The dryer is provided with a drum body (16) and a process air return duct housing (11) surrounded with outer isolation (12). The rotating drum is reversed by the radial process air flow (2). The top of the drum body emits heat from the process air flow.

Description

State of the art

• a) Kondensationstrockner
• b) Ablufttrockner die das Waschgut in einer rotierenden Trommel zur Trocknung bringen indem sie durch eine, meist elektrische, Heizung erwärmte Luft zum Austreiben der Feuchtigkeit aus der Wäsche durch die Trommel führen und –
• c) beim Kondensationstrockner sodann den mit Feuchtigkeit beladenen Luftstrom zu einer Wärmetauschereinheit führen, an der die feuchte Luft abgekühlt wird und Ihre Feuchtigkeit als Kondensat abgibt, danach über eine Heizung zur Trockner Trommel zurückgeführt wird, worauf der Prozess wieder von vorne beginnt, also einen geschlossenen Feuchtluft-Umluft Kreislauf hat.
• d) beim Ablufttrockner ins Freie leiten, wo an einer anderer Stelle die Ansaugung für den Feuchtluftstrom erfolgt und dieser wieder der Trockentrommel über die Heizung zugeführt wird, einem offenen Feuchtluft-Kreislauf.

Tumble dryers of the systems are generally known

• a) Condensation dryer
• b) exhaust air dryers bring the laundry in a rotating drum to dry by passing through a, usually electrical, heating heated air to expel the moisture from the laundry through the drum and
• c) in the condensation dryer then carry the moisture-laden air flow to a heat exchanger unit at which the moist air is cooled and releases your moisture as condensate, then returned to the dryer drum via a heater, after which the process starts again from the beginning, so a closed Humid air circulation circuit has.
• d) at the exhaust air dryer lead to the outside, where at another point the suction for the damp air flow takes place and this is again fed to the drying drum via the heater, an open humid air circuit.

Criticism of the state of the art

Both Dryer systems is mean that they are relatively large Heat losses work. It is known that systems with Heat recovery in the form of intermediate Heat exchangers and / or very expensive heat pumps between exhaust and feed air of the process air after leaving the Drum - especially at the condensation dryers, work to reduce and optimize energy consumption.

See, for example, B. DE 29 14 859 C2 .

In exhaust air dryers one tries by means of heat exchanger or coaxial hose guide z. B. Außen-Zulaufschlauch- and inner exhaust hose to recover heat. Please refer DE 37 17 425 A1

For this purpose, for example, the dryer drum front and rear wall and the drum shell are insulated or provided with vacuum chambers to reduce the heat loss from the drum. See also DE81 05 912 U1 . JP2000225298A . JP03032700A ,

Strength Heat losses also occur on the walls in the Area of heating, mostly in the back wall, before the warmed up air enters the drum where it is axial is carried out.

Both Systems is disadvantageous that their drying drum of the dry process air flows through axially. In addition the drum is at the rear Drum wall perforated so that the process air can enter. The heater is located in a heating channel and thus has a greater distance from the actual dry matter. In this heating area, the largest heat losses take place, and one tries to reduce these with expensive means.

Of the Outlet of the humidified process air then takes place at the front Drum wall in the area of the dry material filling window. The full flow around the drum with process air recirculation, as shown by the dryer according to the invention, is very badly possible in Axialströmungsbetrieb and does not bring the desired simple flow opposite the cross flow according to the invention Principle, heat losses must also be accepted here become.

solution

The The solution presented here shows that these losses can be fully countered and the goal is a really good heat recovery is.

Both new drying systems is a drum flow in -Querstrom principle assigned.

The drying drum is flowed through radially and the drum shell has openings in the form of holes or z. B. a grid. The drum is surrounded by a drum housing having an air inlet opening and an air outlet opening. Directly in front of the air inlet is located in the immediate vicinity of the heater. The process air flow ( 2 ) enters here heats up and absorbs moisture when passing through the drum.

He leaves the drum through the drum shell and passes Immediately and immediately to a heat exchanger, the z. B. may also be a heat pipe system. Here is a Heat exchange, which takes place in a directly adjacent process air channel, the outside around the drum housing with more than 180 Angular degree leads around, and this heat to the there flows, flowing cooled process air.

This is the sucked fresh process air at the exhaust air dryer system and - in the condensation dryer after the condensation process in, previously known, condensing heat exchanger cooled Process air of the closed circuit.

This, here called return channel has the task to guide the cool process air and flows around at least half the drum housing. In this case, the process air flow takes the whole, exiting through the drum housing with heat and leads them directly and immediately back to the drum housing inlet opening, where it is again the actual moisture release available. The process air stream has preheated and requires less heating power to provide the desired heating for the Austriebs process. To optimize against heat loss to the outside from the return channel in the dryer housing, inside, this is provided with an insulation on its outside, which prevents even the smallest leak heat to escape.

Between Drum and drum housing is a gap, "S" the naturally against damp air flow misconduct, so around the drum outside, as small as possible is held and with one or more soft penetration barriers, the frictionless against the drum is provided.

These Forcing the air flow back into the drum to absorb moisture.

The, the drum housing enclosing, feedback brings, except the continuous, large reduction loss of heat as a result of the elimination of expensive heat pump systems and simplifies manufacturing and effort on the devices. Furthermore the installation room of the dryer is thermally less stressed, because the total energy consumption decreases.

drawings

The Invention is described below with reference to the drawings, and show the following:

1 and 2 :

The dryer according to the invention in the axial and radial cross-section with the drying drum ( 15 ) and the laundry ( 1 ), the drying drum housing ( 16 ) with the enclosing return channel ( 11 ). The heating element ( 4 ) with the process air stream ( 2 ). Next is shown the isolation of the return channel ( 12 ) and the transit barrier ( 13 ) the heat dissipation ( 14 ), with the gap "S", as well as the heat pipe system ( 10 ), z. B. after the system "Sprenger / de Fries" whose structure and operation is known in the art. However, this may also be a heat exchanger system of another known type, which regulates the heat exchange between supply and discharge of the process air (FIG. 2 ) also accomplished. This heat exchanger unit is structurally as close as possible to the outlet ( 24 ) of the drum housing ( 16 ). This heat losses are avoided in the outgoing channels. About the heat exchanger system ( 10 ) the process air flow ( 2 ) already cooled down to the extent that only one in the dimensions smaller condensate heat exchanger for the condensate precipitation process is needed, since the process air ( 2 ) already cools down so much that it thermally approaches the dew point.

The dryer drum ( 15 ) is shown with the perforated drum shell ( 17 ) the rear floor ( 18 ) and the front floor ( 19 ). The drum bottoms can be optionally perforated. The heater itself is on your side facing away from the drum provided with a radiation protection plate so that the heating ( 4 ) outgoing heat radiation is converted into the convection heat with the process air stream and then through the inlet opening ( 5 ) is supplied to the moisture output. The filling opening ( 22 ) for the dry material is shown functionally. Drum drive and storage are shown without code.

3 :

serves for functional representation of a condensate precipitation process to the dryer according to the invention.

It shows the heat exchanger system arrangement ( 20 ) and for the process air ( 2 ) required movement equipment such as radial blower or cross-flow fan for Kondensationsausfällvorgang in a condensation dryer known type. Shown is also the required cooling air blower ( 9 ) with the cold air stream ( 3 ) for the cooling of the process air below the dew point and the process air blower ( 6 ). The precipitated condensate ( 7 ) is connected to the condensate tray ( 8th ).

4 :

Serves for functional representation of an exhaust air system for the dryer according to the invention. The process air is shown ( 2 ) and the heat exchanger according to the invention ( 10 ) as well as the process air blower ( 6 ).

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 2914859 C2 [0003]
• - DE 3717425 A1 [0004]
• - DE 8105912 U1 [0005]
• JP 2000225298A [0005]
• - JP 03032700 A [0005]

Claims (14)

Dryers for all types of dry goods, especially dryers with maximum energy efficiency, characterized in that the drying drum of a drum housing ( 16 ) and a process air return channel housing ( 11 ) with isolation on the outside ( 12 ) is surrounded. Dryer according to claim 1, characterized in that the rotating drum is also reversing, with radial process air ( 2 ) is flowed through and at least the drum shell is opened by a perforation or a grid allows the flow. Dryer according to claim 1, characterized in that the upward from the drum housing ( 16 ) exiting heat from the process air stream ( 2 ) in the process air return channel ( 11 ) is resumed immediately and to the entrance opening ( 5 ) is returned where it is the moisture release process available again. Dryer according to claim 1, characterized in that the drum housing a process air inlet opening ( 5 ) has opposite a process air outlet opening ( 24 ) is arranged so that the process air a long way through the drum ( 15 ) must take. This outlet opening merges into a channel which channels the process air ( 2 ) continues. Dryer according to claim 1, characterized in that directly in front of or in the immediate vicinity of the inlet opening ( 5 ) a heater ( 4 ), which surrounds the process air (FIG. 2 ) to the required moisture-raising temperature. Dryer according to claim 1, characterized in that between drum ( 15 ) and drum housing ( 16 ) at a suitable point one or more process air passage barriers ( 13 ), the passage of the process air through the drum ( 15 ) and fill the gap "S" in the cross-section of the drum profile in axial section. Dryer according to claim 1, characterized in that the arranged process air return channel ( 11 ) the drum housing ( 16 ) at least radially and largely also on the drum housing walls ( 16 ) encloses. Dryer according to claim 1, characterized in that the process air return channel ( 11 ) in the region of the outlet opening ( 24 ) remains connected to the drum housing outlet channel so far that between the channels formed a heat exchanger system ( 10 ), the still warm process air ( 2 ) immediately extracts the heat contained there and thermally leads the process air close to the dew point. This extracted heat is immediately the still cool process air return flow ( 2 ) and warms it up again. Dryer according to claim 7, characterized in that in solution with heat pipe system ( 10 ) the heat pipe is arranged rising from the heat-receiving side to the heat-emitting side. Dryer according to claim 1, characterized in that the process air return channel ( 11 ) has on the outside an insulation, the further heat losses of the front of the inlet opening ( 5 ) already heated process air ( 2 ) prevented. Dryer according to claim 1, characterized in that the process air ( 2 ) on the way between the drum housing outlet opening ( 24 ) and re-entry into the process air return channel ( 11 ) followed the condensation via heat exchanger systems according to the free state of the art ( 3 ). Dryer according to claim 1, characterized in that in the exhaust system operation with the process air ( 2 ) before entering the return channel ( 11 ) and after leaving the outlet ( 24 ) and behind the heat exchanger system ( 10 ) is moved according to the free prior art. ( 4 ) Dryer according to claim 1-12, characterized in that the drum ( 15 ) the laundry filling opening ( 22 ) also closable on the drum jacket ( 17 ) and the drum housing ( 16 ) as well as the process air return channel on your upward side, above the drum have openings which are each closable and allow the filling of the dryer also from above. Dryer according to claim 1-13, characterized in that in the drum housing outlet channel at ( 10 ) a thermostat controlled damper ( 25 ) for the process air ( 2 ) is arranged during the warming up of the dry material ( 1 ) generates a limited process air flow, which accelerates the warm-up process, thus additionally saving drying time and energy consumption.