DE3032270A1 - Combustion gas energy recovery equipment - comprises heat exchanger in or on flue - Google Patents

Abstract

The equipment recovers energy from the combustion gases of any kind of fire, incorporating a heat exchanger (2) mounted in or on the flue (1). This heat exchanger extracts any surplus heat and uses it for heating washing or swimming-bath water etc., in conjunction with heat pumps. A measuring and control unit can be provided, so that heat is extracted only within the permissible temp. range, and where heat input is relatively low any condensate may be drained into a collector vessel.

Description

Device for energy recovery from the exhaust gases of fireplaces and use for heating and warming purposes

The invention relates to a device with the help of which it is possible to remove the heat content the exhaust gases (flue gases) from fireplaces down to the minimum permissible temperature and use for heating and Heating purposes - e.g. heating of service water - the efficiency of the fireplaces or entire systems increase and thereby save energy and costs.

According to the heating systems as well as the heating operation regulation -HeizAnlV or HeizBetrV- of September 22, 1978, the heat generators for the use of liquid or gaseous fuels must be set up or operated in such a way that the exhaust gas losses do not exceed maximum values. It is known that the fulfillment of this requirement is met with difficulties in most cases because of the incineration.

The task of the device described below is to maintain or fall below the required values, by reducing exhaust gas losses to a minimum by reducing the exhaust gas temperature.

A device to improve the efficiency of water central heating was already with the patent application P 2555 417.0 - 16 at the German patent office from 10.12.1975 and the laid-open specification 2555417 from I7.II. Shown in 1977. The inventor ν — seeks connection in it

SAD ORiQINAL

with heat exchangers through controllable diversion and change the flow rate of the exhaust gases to reduce the temperature of the exhaust gases and thereby the To improve the efficiency of the heating system.

The object of the present invention is to remove any excess heat content from the exhaust gases However, not by means of throttle valves or the like and changing the flow conditions and thus the Peculiarities of the systems with possible sources of interference for the combustion as well as not inconsiderable construction measures at the fireplace or heating system, but without any significant influence on the fireplace To prevent loss of heat through recovery only where there is no effect on the combustion process more can be done.

To solve this problem, the following proposals are made according to the invention:

1. By means of a heat exchanger, the flue gases are given up to amounts of heat after leaving the fireplace withdrawn to reach a minimum permissible temperature.

2. The amount of heat is extracted via a carrier medium.

5. The amount of heat absorbed by the carrier medium is transferred directly or indirectly to the same or a different medium elsewhere.

Embodiments of the invention are shown in the drawings. It represent?

Figure 1: A schematic representation of a fireplace with exhaust pipe and chimney connection, and the devices in the exhaust pipe or to be installed.

Figure 2: A schematic representation of an entire system with direct exchange of heat quantities, e.g. using a heatable hot water storage tank with two connections (Cold water inlet and hot water outlet).

Figure 5: A schematic representation of an entire System similar to Figure 2, (but with three pipe connections.

Figure 4: A schematic representation of an entire System similar to Figure 2, but with four pipe connections.

Figure 5: A schematic representation of an entire System with indirect exchange of heat, e.g. via a second heat exchanger in a heatable storage tank.

Figure 6: A schematic representation of the systems of Figures 2 to 5i, but with non-heatable Save on computer.

The domestic water storage tanks shown in the figures can also be storage heaters or act like that.

The functional processes are described using an example as follows:

According to Figure 1, for example, a heat exchanger is placed in the exhaust pipe with or without an exhaust flap (flue gas flap) (1) (2) and a sensor for the thermostat (3) installed. The heat exchanger (2) can also have a different design to have; e.g. a double-walled exhaust pipe. The components in the exhaust pipe are designed in such a way that that the cross section of the exhaust pipe is insignificantly reduced and the flow resistance of the exhaust gases is insignificant is increased.

According to Figure 2, the heat exchanger (2) has a pump with a check valve (4-) and two shut-off cocks with detachable Connections (5) to the cold water inlet (6) and the hot water inlet (7) of a heatable (8) normal Hot water tank (14-) connected. In addition to the usual equipment such as safety group (9) »circulation line with pump and check valve (10), storage thermostat (11) and thermometer (12) is located in the Another thermostat (13).

The heating of the memory (8) is depending on requirements and Exhaust gas volume - summer or winter - switched off or on. If the storage tank heating is in operation, the water in the storage tank depending on the position of the thermostat (11) heated to the associated temperature.

During the operating hours of the fireplace (boiler), the pump (4) is switched on and it circulates the carrier medium - e.g. water - through the heat exchanger (2) and through the storage tank (14), whereby the The amount of heat extracted from the flue gases is transferred to the storage tank water. The storage water can thereby up to

to the temperature preselected on the cylinder thermostat (13) which then controls the pump (A-).

During downtimes of the fireplace after previous operation - i.e. times without flowing exhaust gases - the pump (A-) remains in operation until the temperature in the exhaust pipe falls below the temperature set on the thermostat (3) - usually approx. 1A-0 ⁰ C -.

If the fireplace is in operation for a long time and there is little water being drawn off, the water temperature in the storage tank and thus the inlet temperature in the heat exchanger (2) above the desired or permissible level - for domestic water as is well known, if possible, climb a maximum of 60C. In this case the circulation line is used as a temperature limiter. Instead of the circulation line one or part of a room heating system - e.g. underfloor heating or the like can also be connected will. If this operating state is present, the pump (10) is switched on via the thermostat. The pump (10) remains in operation until the desired hot water temperature is reached again. The on this The amount of heat withdrawn in a wise manner is, in turn, especially since this operating situation usually only occurs in winter fully used.

The functional sequence is also the same for the examples according to FIGS. 3 »A-, 5 and 6.

The thermostats used in FIGS. 1 to 6 according to the above description can be used to fulfill identical or far-reaching tasks according to the invention also through other components or systems of the Measurement and control technology are replaced.

According to the invention, in addition to water, other media and other systems can also be heated with the device - e.g. B. Heating systems - are operated.

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Claims (6)

Claims 1. Device for energy recovery from the exhaust gases of any type of fireplace, characterized in that there is a flue in, on or on the exhaust pipe or another device for discharging the exhaust gases is a heat exchanger of any shape and suitable or required size, by means of whose excess heat is withdrawn from the exhaust gases when it occurs and when it is needed and used for domestic water or Swimming pool water heating and heating purposes, also in connection with heat pumps, can be used. 2. Device according to claim 1, characterized in that only when excess amounts of heat accumulate the recovery plant is in operation and the recovered Amount of heat via direct or indirect heat exchange elsewhere for use gives away. 3. Device according to claim 1, characterized in that that with the help of a measuring and control device of any kind, a heat quantity extraction from the exhaust gases only in one permissible temperature range takes place. 4-, device according to claim 1, characterized in, that with the help of a measuring and control device the desired or maximum permissible inlet temperature (return temperature) is not exceeded will. 5. Device according to claims 1 and 2, characterized in that that even with a small amount of excess heat and thus limited heat recovery or, in the case of high consumption, the secondary system this can be operated with full efficiency by means of separate or built-in Heating of any kind in connection with measuring and control devices keeps the inlet temperature at a minimum value can be kept at a certain distance from the maximum value. 6. Device according to claim 1, characterized in that that the exhaust pipe or other device with the same tasks is designed in such a way that it is not exceeded a minimum inlet temperature. possibly forming condensation water not in the exhaust pipe or other attachments, but without pressure and gas in a drain, container or similar device can run.