EP1045214B1 - Absorption heat pump and method for operating an absorption heat pump - Google Patents

Abstract

A burner (2) vaporises a refrigerant solution into an condenser (13) containing a heat exchanger feeding a radiator (34) and absorber (6) back to the boiler (1) in a closed circuit. Refrigerant then passes through a throttle valve (12) and an evaporator (11) to provide cooling. The system is controlled by a regulator (17) according to data from an outside thermostat (14), a back flow thermostat (15) a forward flow thermostat (16).

Description

The present invention relates to an absorption heat pump and a method of operating an absorption heat pump.

In absorption heat pump systems, a solution containing a refrigerant, for example, by means of a gas or oil burner, heated electrically or with the aid of additional heat exchanger by means of waste heat or solar energy in a digester to expel refrigerant as refrigerant vapor from the solution. The refrigerant vapor is brought by this process to a high temperature level or high pressure level. The refrigerant vapor is then condensed in a condenser against a heating medium and thus supplies heat to the heating means. The highly cooled and expanded refrigerant is an evaporator, in which it is evaporated against a medium which supplies ambient energy to the refrigerant, and then fed to at least one absorber.

The refrigerant depleted solution from the digester is fed via a heat exchanger to the absorber, where the refrigerant depleted solution with refrigerant which has passed through the evaporator unites. The resulting heat of solution is provided to the expeller process and the consumer or discharged only to the consumer. The resulting rich in refrigerant solution from the absorber is pumped by means of a solution pump from the low pressure level of the absorber, which corresponds approximately to the Verdampfüngsdruck, to a high pressure level and fed again to the digester. Finally, the heating means heated in the condenser is supplied to a consumer and the heating means cooled by the consumer are returned to the condenser.

If the heating of the digester is switched off in an absorption heat pump system, the concentration stratification prevailing during operation of the absorption heat pump is reduced in the digester and brought to the level of the solution poor in refrigerant. During a transient start-up process, it is only by gradually supplying rich solution that a concentration stratification required for the stationary operating state can be built up in the digester. After a shutdown of the digester, therefore, when restarting such a system considerable start-up times and energy losses are to be accepted.

In order to overcome these problems, EP-B-0 202 432 proposes a cyclic absorption heat pump system in which the high-pressure part and the low-pressure part are locked at standstill by means of solenoid valves in order to minimize the restarting losses. A disadvantage of this technique is that when the burner power is changed, e.g. may be caused by temperature fluctuations, a heat pump operation is not always guaranteed.

US-A-4596122 discloses an absorption heat pump according to the preamble of claim 2.

The invention is therefore an object of the invention to provide an absorption heat pump and a method for operating an absorption heat pump of the type described above, in which or at which the energy losses incurred during startup of the absorption heat pump are minimized while still reliable operation of the heat pump is guaranteed.

This object is achieved in a method for operating an absorption heat pump, as defined in the preamble of claim 1, which is based on EP-B-0 202 432, solved in that the outside temperature and the temperature of the heating medium are measured and the performance of the Burner is set in response to the measured temperature values, that the amount of refrigerant supplied to the evaporator is controlled, that the amount of the refrigerant-depleted solution supplied to the at least one absorber is controlled, and further that the delivery rate of the solution pump is controlled.

Accordingly, this object is further achieved with an absorption heat pump as defined in the preamble of claim 22, which is also based on EP-B-0 202 432, by further comprising: a first control device which arranges an outdoor one Outside sensor for measuring the outside temperature, at least one Heizmittelfühler for measuring the temperature of the heating means, and a first controller for controlling the power of the burner in dependence on the measured temperature values, a second control device for controlling the amount of refrigerant supplied to the evaporator, a third control device for controlling the amount of the refrigerant-depleted solution fed to the at least one absorber, and a fourth regulating device for controlling the delivery rate of the solution pump.

The inventive solution, which allows modulating operation of the absorption heat pump by means of said control and regulating circuits, transient start-up losses are minimized while at the same time ensuring reliable heat pump operation. A clocking operation, as was provided in the systems proposed in the prior art, is prevented by the modulating technique.

For reasons of clarity, the control and regulation processes involved in the inventive concept, ie the burner control, the condensate throttle control, the solution throttle control and the solution pump control, are separated from each other described. It is understood, however, that in the method and the apparatus according to the invention all four of said control and regulation processes are implemented simultaneously.

FIG. 1

eine schematische Darstellung des Aufbaus einer Absorptionswärmepumpe sowie einer darin verwendeten Brennersteuerung nach der Erfindung zeigt;

FIG. 2

bis 4 Darstellungen ähnlich FIG. 1 sind, in welchen Ausführungsbeispiele der gemäß dem vorliegend beschriebenen Absorptionswärmepumpenkonzept verwendeten Kondensatdrosselregelung veranschaulicht sind;

FIG. 5

bis 7 Darstellungen ähnlich FIG. 1 sind, in welchen Ausführungsbeispiele der gemäß dem vorliegend beschriebenen Absorptionswärmepumpenkonzept eingesetzten Lösungsdrosselregelung veranschaulicht sind; und

FIG. 8

eine Darstellung ähnlich FIG. 1 ist, in welcher ein Ausführungsbeispiel einer gemäß dem vorliegend beschriebenen Absorptionswärmepumpenkonzept verwendeten Lösungspumpenregelung dargestellt ist.

The invention, whose preferred embodiments are given in the subclaims, will be explained below with reference to the drawings in detail, wherein

FIG. 1

a schematic representation of the structure of an absorption heat pump and a burner controller used therein according to the invention;

FIG. 2

to 4 representations similar to FIG. 1, in which embodiments the condensate restrictor used in accordance with the presently described absorption heat pump concept are illustrated;

FIG. 5

to 7 representations similar to FIG. 1, in which embodiments of the solution throttle control system used according to the presently described absorption heat pump concept are illustrated; and

FIG. 8th

a representation similar to FIG. 1, in which an embodiment of a solution pump control system used in accordance with the presently described absorption heat pump concept is illustrated.

As shown in FIG. 1, an absorption heat pump includes a digester 1 in which a solution containing a refrigerant is heated by means of a burner 2 to expel refrigerant as refrigerant vapor from the solution. In the embodiment of FIG. 1, the refrigerant vapor in a line 30 is fed via a rectifier 3 to a condenser 13, in which the refrigerant vapor is condensed against a heating medium. The heating means heated in this way is in turn fed into a line 32, the so-called supply, to a consumer 34, for example a radiator.

Heating means, which has passed through the consumer 34, returns via a line 36, the so-called return, back to the absorption heat pump. In particular, the heating medium cooled in the consumer 34 can be heated in an exhaust gas heat exchanger 9 against hot exhaust gas leaving the burner 2, which is discharged or otherwise disposed of or processed at 44, before it is fed to an absorber 6. After passing through the absorber 6, which may be, for example, a plate heat exchanger, the heating means in a line 38 again supplied to the capacitor 13, so that there is a closed Heizmittelkreis.

The in the condenser 13 against the heating means strongly cooled and expanded refrigerant is fed in a line 40 to the aftercooler 10, of which from it is fed via a throttle point 12 to an evaporator 11. In the evaporator 11 ambient energy is supplied to the refrigerant, which may in particular be heat in the environment (indicated at 42 in FIG 1) of the consumer 34 to be heated building, for example in the soil, in water, in air , especially stored in brine.

Refrigerant leaving the evaporator 11 is again passed through the aftercooler 10 and from there to the absorber 6. In the absorber 6 or, as shown in FIG. 1, in a mixer 46 arranged in front of the absorber, the refrigerant is mixed with solvent which has left the digester 1 via a line 48. The resulting heat of solution is made available to the expeller process in the boiler 1 and the consumer 34 or discharged only to the consumer 34. The solution rich in refrigerant leaving the absorber 6 is pumped to a high pressure level after passing a solution reservoir 7 by means of a solution pump 8 from the low pressure level of the absorber 6 which approximately corresponds to the evaporation pressure, and fed again to the digester 1. Here, the refrigerant-rich solution of the absorber 6 as shown in FIG. 1 through the rectifier 3 and a heat exchanger 4 are passed, in which the refrigerant-rich solution is subjected to a heat exchange against the boiler 1 leaving the refrigerant vapor or the boiler 1 leaving solvent. Refrigerant, which is already condensed in the rectifier 3, is fed back to the digester 1 via a return 50.

The general structure of the present absorption heat pump described so far is common to all embodiments described below and will therefore not be described again in the description of the remaining drawings. The following description focuses primarily on the individual control and regulation aspects of the inventive concept. As already mentioned, not all control and control aspects are shown simultaneously in the individual drawings, but the burner control, the condensate throttle control, the solution throttle control and the solution pump control are explained in succession with reference to schematic partial drawings.

With reference to FIG. 1, the components relating to the burner control will be described first. The aim of the Absorptionswärmepumpenbrennersteuerung is to achieve a heat demand of the building to be heated adapted control of the burner power, so as to ensure a continuous operation of the absorption heat pump. The presently described concept is based, unlike the known systems described above, on the realization that it is quite useful and energetically rewarding with appropriate control and regulation of the system, the absorption heat pump with a reduced heating demand not completely off but herunterzuregeln, since otherwise the losses occurring at a restart of the system outweigh the energy savings achieved by the shutdown.

In the device according to FIG. 1, an outside sensor 14 for measuring the ambient temperature and a heating medium sensor for measuring the temperature of the heating means are provided, wherein the heating medium sensor may be implemented as a return sensor 15 for detecting the return temperature or as a flow sensor 16 for detecting the return temperature. The outside sensor 14 and the return sensor 15 and / or the flow sensor 16 are connected to a controller 17 whose output is connected to the burner 2. In the burner 2, this is a controllable burner with a power consumption of, for example, 4 to 18 kW. The controller 17 compares the measured return or flow temperature with a setpoint and throttles the burner power at approach of the return flow or the flow temperature to the setpoint. The control can be done in accordance with preset heating curves. Thus, on the one hand, the burner output can be directly related to the measured outside temperature by assigning certain outside temperature values to certain burner power consumption values. For example, an external temperature of +15 ° C could be assigned a burner output of 4 kW, while at an outside temperature of -15 ° C the burner output should be 13 kW. However, the flow and / or the return temperature can serve as setting parameters for the performance of the burner. For example, an outside temperature of +15 ° C can be assigned a return temperature of 25 ° C, while an outside temperature of -15 ° C is assigned a return temperature of 45 ° C. In addition to the comparison of setpoint and actual value of the return or the flow temperature, however, the temperature spread of the heating means, i. the difference between flow and return temperature, serve as a control parameter. The aforementioned types of control can be implemented individually or jointly. The described burner control thus adapts the entire heat energy generated by the absorption process modulating the heat demand of the building to be heated, for example, by individual settings (for example, radiators are closed) or by external influence (variation of solar radiation, etc.) can constantly change.

In order to ensure the condensation of the refrigerant in the condenser over the entire modulating heat pump operation in the modulating burner control described above, the condensate throttle is controlled according to the presently described concept. The condensate throttle control also has the task of avoiding an unnecessarily high condensation pressure and thus contributes to an improvement of the overall efficiency.

As in the following with reference to the FIGN. 2 to 4 is explained in detail, the condensate throttle can be done with the aid of several different control parameters. In particular, as shown in FIG. 2, by means of a pressure sensor 18, the pressure p _KKein of the refrigerant _{vapor entering} the condenser 13 is measured. This pressure value _pKKin can then be converted into a temperature _{value TKN} with the aid of the Ziegler fundamental _{equation familiar to the person skilled in the art} . By means of a regulator 19, in the illustrated example, a PID controller, then the calculated temperature _value T _{KKein is compared} with a reference temperature to form an output signal for controlling a continuously controllable actuator. In the in FIG. 2 embodiment is used as the reference temperature, the temperature T _flow of the emerging from the condenser 13 heating means, which is measured by means of a temperature sensor 16. If the temperature difference T _KKein -T _{supply is} less than a predetermined desired value of, for example, 1 to 4 K, then the amount of the refrigerant supplied to the evaporator 11 is reduced by means of the controllable throttle point 12, which may be designed, for example, as a pulse width modulated valve. If, on the other hand, the said temperature difference is greater than the predetermined desired value, the quantity of refrigerant supplied to the evaporator 11 is increased. By means of the setpoint ensures that always sets a condensate supercooling of about 2 to 5 K. If the difference T _KNo - T _{flow is} equal to the specified value, the valve position is optimal.

A variant of the condensate throttle control of FIG. 2 is shown in FIG. 3 outlined. Instead of the pressure sensor 18 (FIG. 2), a temperature sensor 20 is provided here, which _detects the temperature T _KKaus of the refrigerant exiting from the condenser 13. This temperature T _KKaus is again compared with the temperature T _flow of the emerging from the condenser 13 heating medium. Based on the determined with a controller 19 temperature difference between the flow temperature T _flow , which corresponds to the condensation temperature, and the temperature T _KKaus the condensate can be the prevailing condensate _supercooling rate. If a setpoint is specified for the condensate subcooling, then the throttling point 12 can be opened or closed completely or partially based on a comparison between said temperature difference and this setpoint. The nominal value of condensate subcooling is preferably in the range between 2 and 5 K.

Another variant of the condensate throttle control of FIG. 2 is shown in FIG. 4 shown. The embodiment of FIG. 4 differs from that of FIG. 3 in that the temperature of the heating means is not measured at the outlet of the condenser 13 but at its inlet. The measured by a temperature sensor 20 temperature T _KKaus exiting the condenser 13 refrigerant is then compared with the measured by a temperature sensor 21 temperature T _HNo of entering the condenser 13 heating means, for which purpose the controller 19 preferably comprises a differential former. As in the above embodiments, the resulting from the comparison of the two temperatures mentioned temperature difference again with a Setpoint compared and the throttle point are regulated in dependence on this comparison.

• der Durchfluß und somit die Konzentration der an Kältemittel armen Lösung nehmen zu,
• der spezifische Lösungsumlauf wird größer,
• das Lösungsfeld wird weiter zusammengezogen,
• die Konzentrationsdifferenz und damit auch die Temperaturdifferenz zwischen Kesselfuß und Kesselkopf des Kochers verringert sich,
• die Konzentration der "reichen" Lösung im Absorber wird kleiner
• der Niederdruck sinkt.

Referring to the FIGN. 5-7, the solution throttle control employed in the present absorption heat pump concept will be explained below. The solution throttle 5 shown in the drawings determines the flow of the low-refrigerant solution discharged from the digester 1 through the heat exchanger 4 and mixed in the mixer 46 (FIG.1) with the refrigerant exiting the after-cooler 10 before entering the refrigerant Absorber 6 is initiated. By adjusting the solution throttle 5 of operated at low pressure absorber or the evaporation pressure is affected. The aim of this scheme is to keep the low pressure in each operating state of the heat pump so that the evaporator 11 absorbs the maximum possible energy and at the same time ensures that does not set an unnecessarily high mass flow of the refrigerant-poor solution. When the solution throttle 5 is opened, this has a number of effects:

• the flow and thus the concentration of the refrigerant-poor solution increase,
• the specific solution circulation gets bigger,
• the solution field is further contracted,
• the difference in concentration and thus also the temperature difference between boiler foot and boiler head of the cooker decreases,
• the concentration of the "rich" solution in the absorber becomes smaller
• the low pressure drops.

A closure of the solution throttle has correspondingly opposite effects.

According to FIG. 5, the temperature T _KVein of the refrigerant supplied to the evaporator 11 is measured by means of a temperature sensor 22. With the aid of a second temperature sensor 23, the temperature T _KVaus of the exiting the evaporator 11 refrigerant is detected. A PID controller 26 forms a difference from the two measured temperature values and applies a control signal to the solution throttle 5 based on the result of the subtraction. In particular, the ascertained temperature difference is compared with a predetermined desired value, similar to the method described above, with a particularly preferred range for this desired value ranging from 7 to 10 K in the presently described embodiment. If the determined temperature difference is greater than the predetermined desired value, the solution throttle 5 is closed; If the determined temperature difference is smaller than the predetermined desired value, the solution throttle 5 is opened. The control of the solution throttle 5 can moreover also by a measurement of the flow temperature, as described with reference to FIGS. 2 and 3 were influenced by the setpoint for the difference between the temperature T _KVein of the evaporator 11 supplied refrigerant and the temperature T _KVaus of the exiting the evaporator 11 refrigerant in dependence on the flow temperature T _{flow is} varied. For example, the control can be designed so that the setpoint for said temperature difference at the evaporator at a flow temperature of 30 ° C, for example, 14 K, while this setpoint is lowered at a flow temperature of 50 ° C to eg 7 K.

In the in FIG. 6 sketched variant of the solution throttle control according to FIG. 5, the temperature T _KVein measured by the temperature sensor 22 of the refrigerant supplied to the evaporator 11 is compared with the temperature T _MV of the medium supplied to the evaporator 11 (brine, water, air, etc.) measured by means of a temperature sensor 24. Based on this comparison, the controller 26 delivers a control signal to the solution throttle 5 as a function of a predetermined desired value.

Another variant of the solution throttle control is shown in FIG. 7, in which the pressure p _KVaus of the refrigerant emerging from the aftercooler 10 and by means of a temperature sensor 24 are measured by means of a pressure _sensor 28, the temperature T _KVaus of emerging from the evaporator 11 refrigerant. The measured pressure value can then, as described above with reference to the presently used condensate throttle control, be converted into a temperature value and compared by subtraction with the temperature value measured by means of the temperature sensor 24. The thus determined temperature difference is then compared with a predetermined setpoint value to obtain a control signal for the solution throttle 5. The in FIG. 7 arrangement of the pressure transducer 28 and the temperature sensor 24 could be further modified in that both transducers are arranged at substantially the same point of the process flow. In particular, both the pressure sensor 28 and the temperature sensor 24 could be placed between the aftercooler 10 and the mixer 46 or between the evaporator 11 and the aftercooler 10.

FIG. Figure 8 shows an embodiment of the solution pump control used in the present absorption heat pump concept. As with reference to FIG. 1, the solution rich in refrigerant leaving the absorber 6 after passing through the solution reservoir 7 is pumped by means of a solution pump 8 from the low pressure level of the absorber 6 to a high pressure level and supplied again to the digester 1. In the case of FIG. 8 illustrated embodiment of the solution pump control is detected by means of a arranged in the solution reservoir float 7 29, advantageously a magnetic inductive float, the level of the solution reservoir 7 and based on the measured level, the speed of the solution pump 8 and thus the solution mass flow adapted to the process.

Claims (34)

1. Method for operating an adsorption heat pump in which

   (a) a coolant containing solution is heated within a boiler (1) by means of a burner (2) to expel coolant as coolant vapour;

   (b) the coolant vapour is condensed within a condenser (13) against a heating medium to provide heat to the heating medium;

   (c) the coolant is passed from the condenser to a vaporiser (11) in which it is vaporised against a medium, and subsequently is passed to at least one absorber (6);

   (d) coolant depleted solution is passed from the boiler via a heat exchanger (4) to the at least one absorber wherein the coolant-depleted solution is combined with coolant which has passed the vaporiser;

   (e) coolant-rich solution is pumped from the absorber to a high-pressure level by means of a solution pump (8) and again is provided to the boiler; and

   (f) the heating medium which has been warmed within the condenser (13) is provided to a user, and the heating medium, which has been cooled by the user is returned to the condenser;
   characterised in that

   (g) the ambient temperature and the temperature of the heating medium are measured, and the power output of the burner (2) is adjusted in dependency of the measured temperature values.

   (h) the amount of coolant provided to the vaporiser (11) is regulated (19);

   (i) the amount of coolant depleted solution which is provided to the at least one absorber (6) is regulated; and

   (j) the delivery of the solution pump (8) is regulated.
2. Method as in claim 1, characterised in that the_ coolant leaving the condenser (13) is passed into indirect heat exchange with coolant leaving the vaporiser before it is passed to the vaporiser (11).
3. Method as in claim 1 or 2, characterised in that the temperature (T_return) of the heating medium is measured after having passed the user (return temperature)
4. Method as in claim 3, characterised in that the return temperature (T_return) repeatedly is measured and

   (g₁) the measured value of the return temperature is compared to a set-point; and

   (g₂) the burner output is throttled when the measured value of the return temperature approaches the set-point temperature of the return temperature.
5. Method as in any one of claims 1 to 4, characterised in that the temperature (T_flow) of the heating medium passed from the condenser to the user is measured (flow temperature).
6. Method as in claim 5, characterised in that the flow temperature (T_flow) is repeatedly measured and

   (g₁) the measured value of the flow temperature is compared to a set-point; and

   (g₂) the burner output is throttled when the measured value of the flow temperature approaches the set-point of the flow temperature.
7. Method as in any one of the preceding claims, characterised in that the return temperature (T_return) and the flow temperature (T_flow) are measured repeatedly and

   (g₁) for each measurement the difference of the measured values of the flow temperature and the return temperature is formed; and

   (g₂) the burner output is reduced when the difference of one measurement is smaller than that of a preceding measurement.
8. Method as in any one of the preceding claims, characterised in that the ambient temperature (T_A) repeatedly is measured and the burner output is increased when the ambient temperature decreases.
9. Method as in any one of the preceding claims, characterised in that

   (h₁) the pressure (p_CCin) of the coolant vapour entering the condenser (13) and the temperature (T_flow) of the heating medium leaving the condenser are measured and

   (h₂) the amount of coolant provided to the vaporiser (11) is adjusted in dependency of the measured pressure and temperature values (p_CCin, T_flow).
10. Method as in claim 9, characterised in that

    (h₂₁) the measured pressure value (p_CCin) is converted into a temperature value (T_CCin), and using the thus calculated temperature value (in Kelvin) and the flow temperature (in Kelvin) a set-point A is calculated according to the following formula (I) $$\mathrm{A}={\mathrm{T}}_{\mathrm{c}\mathrm{c}\mathrm{in}}-{\mathrm{T}}_{\mathrm{flow}}-\mathrm{B}$$

    

    wherein B has a value of between 0.5 and 10 K, preferably between 1 and 4 K; and

    (h₂₂) the amount of coolant provided to the vaporiser (11) is increased when A is greater than zero; and

    (h₂₃) the amount of coolant provided to the vaporiser (11) is reduced when A is less than zero.
11. Method as in any one of claims 1 to 8, characterised in that

    (h₁) the temperature (T_CCout) of the coolant leaving the condenser (13) and the temperature (T_flow) of the heating medium leaving the condenser are measured; and

    (h₂) the throttle (12) is adjusted in dependency of the measured temperature values (Tccout, T_flow).
12. Method as in claim 11, characterised in that

    (h₂₁) the difference of the measured temperature values is compared with a set-point D in accordance with the following formula (II) $$\mathrm{C}=\left({\mathrm{T}}_{\mathrm{flow}}-{\mathrm{T}}_{\mathrm{C}\mathrm{C}\mathrm{out}}\right)-\mathrm{D}$$

    

    to obtain a set-point C, wherein D has a value of between 1 and 10 K, preferably between 2 and 5 K; and

    (h₂₂) the amount of coolant provided to the vaporiser (11) is increased when C is greater than zero; and

    (h₂₃) the amount of coolant provided to the vaporiser (11) is reduced when C is less than zero.
13. Method as in any one of claims 1 to 8, characterised in that

    (h₁) the temperature (T_CCout) of the coolant leaving the condenser and the temperature (T_HCin) of the heating medium entering the condenser (13) are measured; and

    (h₂) the throttle (12) is adjusted in dependency of the measured temperature values (Tccout, T_HCin).
14. Method as in claim 13, characterised in that

    (h₂₁) the difference of the measured temperature (T_CCout) of the coolant leaving the condenser and the temperature (T_HCin) of the heating medium entering the condenser (13) is calculated; and

    (h₂₂) the throttle (12) is adjusted in dependency of the calculated difference.
15. Method as in claim 14, characterised in that the said measuring and calculating operations are repeatedly conducted, and the open area of the throttle (12) is reduced when the temperature difference increases, and is increased, respectively, when the temperature difference decreases.
16. Method as in any one of the preceding claims, characterised in that

    (i₁) the temperature (T_CVin) of the coolant provided to the vaporiser (11) and the temperature (T_CVout) of the coolant leaving the vaporiser (11) are measured; and

    (i₂) the amount of coolant depleted solution provided to the at least one absorber (6) is adjusted in dependency of the measured temperature values (T_CVin, T_CVout).
17. Method as in claim 16, characterised in that

    (i₂₁) the difference of the measured temperatures (T_CVin, T_CVout) is compared with a set-point F in accordance with the following formula (III) $$\mathrm{E}=\left({\mathrm{T}}_{\mathrm{C}\mathrm{V}\mathrm{in}}-{\mathrm{T}}_{\mathrm{C}\mathrm{V}\mathrm{out}}\right)-\mathrm{F}$$

    

    in order to obtain a set-point E; and

    (i₂₂) the amount of coolant depleted solution provided to the at least one absorber (6) is increased when E is greater than zero; and

    (1₂₃) the amount of coolant depleted solution provided to the at least one absorber (6) is reduced when E is less than zero;
18. Method as in any one of claims 1 to 15, characterised in that

    (i₁) the temperature (T_CVin) of the coolant provided to the vaporiser (11) as well as the temperature (T_MVin) of the medium provided the vaporiser (11) are measured; and

    (i₂) the amount of coolant depleted solution provided to the at least one absorber (6) is adjusted in dependency of the measured temperature values (T_CVin, T_MVin).
19. Method as in claim 18, characterised in that

    (i₂₁) the difference of the measured temperature values (T_CVin, T_MVin) is compared with a set-point H in accordance with the following formula (IV): $$\mathrm{G}=\left({\mathrm{T}}_{\mathrm{M}\mathrm{V}\mathrm{in}}-{\mathrm{T}}_{\mathrm{C}\mathrm{V}\mathrm{in}}\right)-\mathrm{H}$$

    

    to obtain a set-point G; and

    (i₂₂) the amount of coolant depleted solution provided to the at least one absorber (6) is increased when G is greater than zero; and

    (i₂₃) the amount of coolant depleted solution provided to the at least one absorber (6) is reduced when G is less than zero.
20. Method as in any one of claims 1 to 15, characterised in that

    (i₁) the pressure (p_CVout) of the coolant leaving the vaporiser (11) as well as the temperature (Tcvout) of the coolant leaving the vaporiser (11) are measured, and

    (i₂) the amount of the coolant-depleted solution provided to the at least one absorber (6) is adjusted in dependency of the measured pressure and temperature values (p_CVout, T_CVout).)
21. Method as in claim 20, characterised in that

    (j₂₁) the measured pressure value (p_CVout) is converted into a temperature value T_vaporisation, and using the thus calculated temperature value (in Kelvin) and the temperature (T_CVout) of the coolant leaving the vaporiser (11) a set-point L is calculated in accordance with the following formula (V) $$\mathrm{L}={\mathrm{T}}_{\mathrm{vaporisation}}-{\mathrm{T}}_{\mathrm{C}\mathrm{V}\mathrm{out}}-\mathrm{M}$$

    

    wherein M preferably has a value of between 4 and 15 K; and

    (j₂₂) the amount of coolant-depleted solution provided to the at least one absorber (6) is increased when L is less than zero; and

    (j₂₃) the amount of coolant-depleted solution provided to the at least one absorber (6) is decreased when L is greater than zero.
22. Method as in any one of the preceding claims, characterised in that

    (j₁) the coolant-rich solution coming from the absorber is passed through a solution storage vessel (7),

    (j₂) the liquid level within the solution storage vessel is measured, and

    (j₃) the discharge flow of the solution pump (8) is adjusted in dependency of the measured liquid level.
23. Adsorption heat pump comprising

    (a) a boiler (1) for reception of a coolant-containing solution;

    (b) a burner (2) for providing heat to the boiler (1) to produce coolant vapour;

    (c) a condenser (13);

    (d) conduit means (30) for passage of the coolant vapour from the boiler to the condenser;

    (e) conduit means (32, 36) for passage of a heating medium which has been warmed within the condenser by means of condensing coolant vapour from the condenser to a user (34) as well as for returning of heating medium which has been cooled by the user to the condenser;

    (f) a vaporiser (11) for vaporisation of the coolant against a medium;

    (g) a throttle (12) and conduit means (40) for passage of coolant from the condenser (13) to the throttle (12) and from the throttle to the vaporiser (11);

    (h) at least one absorber (6) as well as conduit means for passage of coolant from the vaporiser to the absorber;

    (i) conduit means (48, 38) for passage of solution which has been depleted in coolant within the boiler to the at least one absorber; and

    (j) a solution pump (8) to pressurise coolant-rich solution which has been withdrawn from the absorber to a high-pressure level as well as conduit means for passage of the coolant-rich solution under high pressure to the boiler;
    characterised by

    (k) a first regulation means comprising an ambient sensor (14) arranged outdoors to measure the ambient temperature, at least one sensor (15, 16) for the heating medium for measuring the temperature of the heating medium, as well as a first regulator (17) for regulating the power output of the burner (2) in dependency of the measured temperature values;

    (l) a second regulation means (16, 18, 19, 20, 21) for regulating the amount of coolant provided to the vaporiser (11);

    (m) a third regulation means (22, 23, 24, 26, 28) for regulation of the amount of coolant-depleted solution passed to the absorber (6);

    (n) a fourth regulation means (27, 28) for regulation of the delivery of the solution pump (8).
24. Absorption heat pump as in claim 23, characterised by an after-cooler (10) in which coolant leaving the condenser (13) is passed into indirect heat exchange with coolant leaving the vaporiser (11) before being passed to the vaporiser (11).
25. Absorption heat pump as in claim 23 or 24, characterised in that the first regulation means comprises a return sensor (15) arranged between the user (34) and the condenser (13) for measuring the temperature (T_retum) of the heating medium after it has passed the user.
26. Absorption heat pump as in any one of claims 23 to 25, characterised in that the first regulation means comprises a flow sensor (34) arranged between the condenser (13) and the user (16) for measuring the temperature (T_flow) of the heating medium passed from the condenser to the user.
27. Absorption heat pump as in any one of claims 23 to 26, characterised in that the second regulation means comprises a temperature sensor (16) to measure the temperature (T_flow) of the heating medium leaving the condenser (13), a pressure sensor (18) to measure the pressure (p_CCin) of the coolant vapour entering the condenser (13), as well as regulator (19) to adjust the amount of coolant provided to the vaporiser (11) in dependency of the measured pressure and temperature values (p_CCin, T_flow).
28. Absorption heat pump as in any one of claims 23 to 26, characterised in that the second regulation means comprises a first temperature sensor (16) to measure the temperature (T_flow) of the heating medium leaving the condenser (13), a second temperature sensor (20) to measure the temperature (T_CCout) of the coolant leaving the condenser as well as a regulator (19) to adjust the amount of coolant provided to the vaporiser (11) in dependency of the measured temperature values (T_flow, T_CCout).
29. Absorption heat pump as in any one of claims 23 to 26, characterised in that the second regulation means comprises a first temperature sensor (20) to measure the temperature (T_CCout) of the coolant leaving the condenser (13), a second temperature sensor (21) to measure the temperature (T_HCin) of the heating medium entering the condenser, as well as a regulator (19) to adjust the amount of coolant provided to the vaporiser (11) in dependency of the measured temperature values (T_CCout, T_HCin).
30. Absorption heat pump as in any one of claims 23 to 26, characterised in that the third regulation means comprises a first temperature sensor (22) to measure the temperature (T_CVin) of the coolant provided to the vaporiser (11), a second temperature sensor (23) to measure the temperature (T_CVout) of the coolant leaving the vaporiser, as well as a regulator (26) to adjust the amount of the coolant-depleted solution provided to the at least one absorber (6) in dependency of the measured temperature values (T_CVin, T_CVout).
31. Absorption heat pump as in any one of claims 23 to 26, characterised in that the third regulation means comprises a first temperature sensor (22) to measure the temperature (T_CVin) of the coolant provided to the vaporiser (11), a second temperature sensor (24) to measure the temperature (T_MVin) of the medium provided to the vaporiser, as well as a regulator (26) to adjust the amount of coolant-depleted solution provided to the at least one absorber (6) in dependency of the measured temperature values (T_CVin, T_MVin).
32. Absorption heat pump as in any one of claims 24 to 27, characterised in that the third regulation means comprises a pressure sensor (28) to measure the pressure (p_CVout) of the coolant leaving the vaporiser (11), a temperature sensor (24) to measure the temperature (T_CVout) of the coolant leaving the vaporiser, as well as a regulator (26) to adjust the amount of coolant-depleted solution provided to the at least one absorber (6) in dependency of the measured pressure and temperature values.
33. Absorption heat pump as in any one of claims 23 to 26, characterised in that the fourth regulation means comprises
    a vessel (7) having a level measuring arrangement (29) for determining the level of a liquid provided into the vessel,
    conduit means for passage of coolant-rich solution withdrawn from the absorber (6) to the vessel (7); and
    a regulator (27) to adjust the delivery of the solution pump (8) in dependency of the measured liquid level.
34. Absorption heat pump as in claim 23, characterised in that the level measurement arrangement (29) comprises an inductive floater.

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