CA1115145A - Method and device for feeding a system for generating and distributing vapor condensable into make-up liquid - Google Patents
Method and device for feeding a system for generating and distributing vapor condensable into make-up liquidInfo
- Publication number
- CA1115145A CA1115145A CA319,774A CA319774A CA1115145A CA 1115145 A CA1115145 A CA 1115145A CA 319774 A CA319774 A CA 319774A CA 1115145 A CA1115145 A CA 1115145A
- Authority
- CA
- Canada
- Prior art keywords
- vapor
- tank
- pressure
- boiler
- liquid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 64
- 238000000034 method Methods 0.000 title claims abstract description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 44
- 238000011049 filling Methods 0.000 claims description 15
- 239000012530 fluid Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 229940090044 injection Drugs 0.000 description 15
- 238000002347 injection Methods 0.000 description 15
- 239000007924 injection Substances 0.000 description 15
- 238000011144 upstream manufacturing Methods 0.000 description 9
- 230000000875 corresponding effect Effects 0.000 description 7
- 238000009834 vaporization Methods 0.000 description 4
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- XUKUURHRXDUEBC-KAYWLYCHSA-N Atorvastatin Chemical compound C=1C=CC=CC=1C1=C(C=2C=CC(F)=CC=2)N(CC[C@@H](O)C[C@@H](O)CC(O)=O)C(C(C)C)=C1C(=O)NC1=CC=CC=C1 XUKUURHRXDUEBC-KAYWLYCHSA-N 0.000 description 1
- 102000004405 Collectins Human genes 0.000 description 1
- 108090000909 Collectins Proteins 0.000 description 1
- 241001163455 Eulepidotis superior Species 0.000 description 1
- ZMJBYMUCKBYSCP-UHFFFAOYSA-N Hydroxycitric acid Chemical compound OC(=O)C(O)C(O)(C(O)=O)CC(O)=O ZMJBYMUCKBYSCP-UHFFFAOYSA-N 0.000 description 1
- 208000036366 Sensation of pressure Diseases 0.000 description 1
- 206010043268 Tension Diseases 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000036961 partial effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000009183 running Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D11/00—Feed-water supply not provided for in other main groups
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D5/00—Controlling water feed or water level; Automatic water feeding or water-level regulators
Abstract
ABSTRACT OF THE DISCLOSURE In a system for producing, distributing and utilizing condensable vapor comprising at least one boiler for producing vapor and at least one vapor utilizing condenser, a method wherein provision is made for direct readmission of condensa-tes from a condensate collecting tank into the boiler and wherein a vaporizable make-up liquid is supplied to the system for the purpose of vapor production by the boiler, wherein the entire quantity of vaporizable make-up liquid is directed to the collecting tank which ensures the whole of the feeding of the boiler with the said vaporizable liquid.
Description
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The present invention relates to improvements in a method of feeding a system for generating and distributing vapor condensable into make-up liquid; it also relates to plants involving applica-tion of the said method.
Usually, in a system for producing and distributing con-densable vapor, the boiler, or each boiler, can be re-fed by - means of a collecting tank for the condensates resulting from the use of the said vapor and of a pump for direct readmission of the said condensates into the boiler or each boiler from the said collecting tank.
Moreover, the said direct readmission of the condensates into the boiler is advantageously interrelated with the liquid level therein.
Also, use can advantageously be made, in the condensate return and collecting circuit, of a certain number of devices such as for example flow lock means, a vapor pump, a thermo-dynamic pump, and admission lock means.
. ,.
The flow lock means is a device allowing, for example, the readmission of condensates from a first circuit into a second circuit where the pressures are not identical.
The vapor pump is a device for applying to the free surface of a liquid contained in a container a sufficient vapor pressure to force the liquid into another circuit.
The thermodynamic pump uses the same principles as the .
; -1- ~
: :
.
vapor pump, but the necessary forcing vapor pressure is obtained in a different manner from that of the vapor pump, as will be seen later.
The admission lock means allow the condensates from a lower-pres-sure circuit to be periodically admitted for example into a higher-pressure vessel. The operating principle of this lock means is different from that of the flow lock means, as will appear later.
; In the first three above mentioned devices, the forced delivery of the condensates contained in a container is obtained by applying to the liquid surface in the said container a vapor pressure Pl higher than the pressure P2 prevailing in the line or the vessel into which the liquid from the said con-tainer is forced, which vapor pressure may be either permanent (flow lock means) or intermittent (vapor pump and thermodynamic pump); in the case of the vapor pump, the vapor pressure Pl is obtained by conveying live vapor, preferably from the vapor system issuing from the boiler, onto the aforesaid liquid sur-face, whereas in the case of a thermodynamic pump the vapor pressure Pl is obtained by heating the liquid in the container containing the condensates to be forced towards the said line or vessel, for example to the condensate collect-ing tank.
The fourth above mentioned device, referred to as the admission lock means, is based on another princple; the container from which the con-densate is forced out is necessarily located at a higher geographical level than that of the line or of the veseel into which the condensate is to be forced, the pressure in the said container being momentarily brought to the value of the pressure P in the said line or the said vessel just long enough for the said container to be emptied of the condensates, by admitting vapor under pressure P into the said container.
One of the objects of the present invention is to allow such de-` vices to be systematically used in plants for producing vapor and returning the condensates to the boiler.
Ano-ther object of the present invention is to allow the smallest possible number of power or mechanical pumps in such plants and even any pumps to be done away with.
Still another object of the present inven-tion is to allow a high-output pump -to be used for delivering water from -the condensate collecting tank to the boiler ~hen it is dèemed appropriate -to use the pump for that purpose.
Lastly, it is another object of the present invention to simplify the control of the liquid level in the vapor generating boiler.
The four above-described devices, namely, the flow lock means, the vapor pump, the thermodynamic pump and the admission lock means, are used in vapor generating, distributing and utilizing or consuming plants of the closed-loop type without separation of -the vapor from the condensat~s do~m -to a low point where -the latter ga-ther in such a manner tha-t, in such plants, the pressure and temperature of the vapor are practically constan-t, except for the pressure losses, in each of the systems, namely, in the case considered, the vapor genera$ing and distributing system and the condensate return system, owing to the vapor and the condensates being in permanent and intimate contact.
Through the various aforesaid devices, each placed a-t a low point of a system, the condensates alone are forced into the condensate collecting tank in order to be directly readmit-ted into the vapor generating boiler. The temperature of the conden-sates in each of the said devices is therefore closely depen-dent upon the vapor pressure in the condensate return sys-tem, and therefore upon its condensation temperature. The final temperature of the condensates gathered in the collec-tin~ tank is therefore the resultant of the temperatures of condensates from various sources.
The condensate collecting tank being closed, i-ts upper portion located above the liquid level therefore contains vapor of self-vaporiza-tion in equilibrium with -the condensates at the corresponding temperature on the saturation vapor ten-- sion curve.
In order to avoid any risk o:E cavitation at -the intake of the pump for direct readmission of the condensates into the vapor-generating boiler from the a:Eoresaid collecting tank, one of the following two precautionary measlres is taken in the present state of the art :
1) either a cooling of the condensates located below the liquid level is brought about so that their tempera-ture is lower than the one corresponding to the then prevailing pressure. By this means the NPSH available for the pump is improved. It will be recalled here tha-t by NPSH is meant the magnitude known as "net positive succion head" ;
:
:;
The present invention relates to improvements in a method of feeding a system for generating and distributing vapor condensable into make-up liquid; it also relates to plants involving applica-tion of the said method.
Usually, in a system for producing and distributing con-densable vapor, the boiler, or each boiler, can be re-fed by - means of a collecting tank for the condensates resulting from the use of the said vapor and of a pump for direct readmission of the said condensates into the boiler or each boiler from the said collecting tank.
Moreover, the said direct readmission of the condensates into the boiler is advantageously interrelated with the liquid level therein.
Also, use can advantageously be made, in the condensate return and collecting circuit, of a certain number of devices such as for example flow lock means, a vapor pump, a thermo-dynamic pump, and admission lock means.
. ,.
The flow lock means is a device allowing, for example, the readmission of condensates from a first circuit into a second circuit where the pressures are not identical.
The vapor pump is a device for applying to the free surface of a liquid contained in a container a sufficient vapor pressure to force the liquid into another circuit.
The thermodynamic pump uses the same principles as the .
; -1- ~
: :
.
vapor pump, but the necessary forcing vapor pressure is obtained in a different manner from that of the vapor pump, as will be seen later.
The admission lock means allow the condensates from a lower-pres-sure circuit to be periodically admitted for example into a higher-pressure vessel. The operating principle of this lock means is different from that of the flow lock means, as will appear later.
; In the first three above mentioned devices, the forced delivery of the condensates contained in a container is obtained by applying to the liquid surface in the said container a vapor pressure Pl higher than the pressure P2 prevailing in the line or the vessel into which the liquid from the said con-tainer is forced, which vapor pressure may be either permanent (flow lock means) or intermittent (vapor pump and thermodynamic pump); in the case of the vapor pump, the vapor pressure Pl is obtained by conveying live vapor, preferably from the vapor system issuing from the boiler, onto the aforesaid liquid sur-face, whereas in the case of a thermodynamic pump the vapor pressure Pl is obtained by heating the liquid in the container containing the condensates to be forced towards the said line or vessel, for example to the condensate collect-ing tank.
The fourth above mentioned device, referred to as the admission lock means, is based on another princple; the container from which the con-densate is forced out is necessarily located at a higher geographical level than that of the line or of the veseel into which the condensate is to be forced, the pressure in the said container being momentarily brought to the value of the pressure P in the said line or the said vessel just long enough for the said container to be emptied of the condensates, by admitting vapor under pressure P into the said container.
One of the objects of the present invention is to allow such de-` vices to be systematically used in plants for producing vapor and returning the condensates to the boiler.
Ano-ther object of the present invention is to allow the smallest possible number of power or mechanical pumps in such plants and even any pumps to be done away with.
Still another object of the present inven-tion is to allow a high-output pump -to be used for delivering water from -the condensate collecting tank to the boiler ~hen it is dèemed appropriate -to use the pump for that purpose.
Lastly, it is another object of the present invention to simplify the control of the liquid level in the vapor generating boiler.
The four above-described devices, namely, the flow lock means, the vapor pump, the thermodynamic pump and the admission lock means, are used in vapor generating, distributing and utilizing or consuming plants of the closed-loop type without separation of -the vapor from the condensat~s do~m -to a low point where -the latter ga-ther in such a manner tha-t, in such plants, the pressure and temperature of the vapor are practically constan-t, except for the pressure losses, in each of the systems, namely, in the case considered, the vapor genera$ing and distributing system and the condensate return system, owing to the vapor and the condensates being in permanent and intimate contact.
Through the various aforesaid devices, each placed a-t a low point of a system, the condensates alone are forced into the condensate collecting tank in order to be directly readmit-ted into the vapor generating boiler. The temperature of the conden-sates in each of the said devices is therefore closely depen-dent upon the vapor pressure in the condensate return sys-tem, and therefore upon its condensation temperature. The final temperature of the condensates gathered in the collec-tin~ tank is therefore the resultant of the temperatures of condensates from various sources.
The condensate collecting tank being closed, i-ts upper portion located above the liquid level therefore contains vapor of self-vaporiza-tion in equilibrium with -the condensates at the corresponding temperature on the saturation vapor ten-- sion curve.
In order to avoid any risk o:E cavitation at -the intake of the pump for direct readmission of the condensates into the vapor-generating boiler from the a:Eoresaid collecting tank, one of the following two precautionary measlres is taken in the present state of the art :
1) either a cooling of the condensates located below the liquid level is brought about so that their tempera-ture is lower than the one corresponding to the then prevailing pressure. By this means the NPSH available for the pump is improved. It will be recalled here tha-t by NPSH is meant the magnitude known as "net positive succion head" ;
2) or the liquid level in the collectlng tank is placed at a sufficiently high geographical level wi-th respect to the ; pump for direct readmission of the condensates into the boiler, taking in-to account the NPSH required by the latter and the loss of pressure between the said liquid level and the pump, at -the rate of flow considered ; under such conditions, the pressure head may be such that the available NPSH thus obtained exceeds at any instant the NPSH required by the assembly constituted by the said pump and the line which is comprised between the condensate collecting tank and that pump.
In both the above cases, use was made, in order to avoid placing the liquid level in the condensate collecting tank at too high a geographical level, of readmission pumps of the low NPSH (i.e. the above-mentioned "required NPSH") type. Such pumps are essentially of the so-called "lateral passage" type based on the principle of semi-volumetric operation. Such pumps are complex in design, very easily damageable, have very small working allowances and are highly expensive. Moreover, they impose very specific and very strict limitations on flow rates, pressures and lay-out. Lastly, their maximum output is limited to values that are incompatible with large-size plants.
In addition, in the present s-tate of the art, two con-curren-t controls of the liquid level in the ~oiler must be performed, namely, a control of the direct readmission of the condensates from the condensate collecting tan~ and a control of the direct admission of make-up water from a feed-tank in-to - the boiler ? -thus complicating the control of the said liquid level and possibly resulting in disturbances in the said con-trol.
All the above considerations have led the Applicant to conceive an installation of the aforesaid type bu-t of a novel design, including a direct readmission of condensates into the boiler. The method according to the present inven-tion, of the type wherein provision is made for direct readmission of condensates from a condensate collecting tank into the vapor generatin~ boiler and wherein a vaporizable make-up liquid is ; supplied to a condensable vapor generating, distributing and utilizing system, for the purpose of vapor production by -the said boiler, is characterized in that the entire quantity of vaporizable make-up liquid is directed to the collecting tank which ensures the whole of the feeding of the boiler with the said vaporizable liquid.
, , Any disturbance in the control of the liquid level in the boiler is -thus avoided since the need for two concurrent controls is eliminated. Indeed, the supply of vaporizable make-up liquid in the plant takes place exclusively at the collecting tank, in case of want of condensates in the la-tter, - i.e. when the quanti-ty of liquid in the collecting tank tends to become too small. In the present specification, the term "quantity of liquid" is used in its broad sense and applies to a mass as well as a volume or a level, and the said quantity ; may be either fixed, possibly zero, or variable.
Thus, according to a characterizing feature of -the pre-sent invention, the inflow of vaporizable liquid into the boiler may be controlled automatically and in such a manner that the water level in -the boiler influences only the direct readmission of the said liquid from the collecting -tank.
According -to another characterizing feature of the present invention, the inflow of vaporizable iiquid into -the boiler from the aforesaid collecting tank is controlled auto-matically in dependence of, exclusively, the water level in the boiler.
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An another advantage of the present inven-tion consists in that, if use is made of a pump, called a feed pump, to supply make-up water to the condensate collecting tank, it is sufficient for such feed-pump to be run intermittently, such runnings being limited to the periodsof time resulting from the regulation of the quantity of liquid in the collecting tank. Consequently, in plants where the make-up liquid constitues only a small portion of the liquid to be admitted to the boiler, electric-power consumption is considerably ; 10 reduced.
According to o~e form of embodiment of the present invention, vapor at maximum pressure is continuously dra~wn from the vapor distributing circuit, and such vapor, possibly after reducing its pressure in a pressure-loss device, is supplied to the aforesaid collecting tank so as to constantly maintain therein a higher pressure than -the pressure corres-: ponding to the temperature of the condensatcs on the vapor tension curve (pressure of self-vaporization).
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This ~orm of embodiment offers the possibility, by using the pump for direct readmission of the condens~es from the said collecting tank into the boiler, of avoiding the ` need for placing the said collecting tank in such a manner that the liquid level therein be permanently at a higher geographical level than that required by the NPSH of the ` pump.
` It is also possible, according to the present invention, to apply a vapor pressure to each liquid surface in the various containers or vessels feeding the tank for collecting all the condensates, the said vapor pressure, which may be either permanent or intermittent, being equal to the pressure in the boiler, except for the pressure losses in the line.
It is therefore possible, irrespective of the various working pressures, temperatures, geographical levels, distan-ces, working hours, rates of flow, controls, and so forth?
for all the condensates in the plant to be gathered in a single collecting tank in which the pressure may be very close to that in the vapor generating boiler. The actual temperature of the condensates in the single collecting tank is the resultant of the mixture of condensates from the various sources. Only the liquid surface layer of a few millimeters in thickness is at a higher temperature as a result of a par-tial condensation of the vapor at high pressure being in contact therewith.
The final mean temperature of the mass of condensates in the single collecting tank is markedly lower than the one corresponding to the then pressure on the saturation vapor tension curve. The NPSH available for the pump for direct readmission of the condensates into the boiler from the said collecting tank is therefore equal to the sum, - of the geographical height (positive or negative) of the liquid level in the tank with respect to the pump suction, and - the height of the imaginary water column representing the dif-ference between the real pressure in the collecting tank and the pressure cor-responding to the temperature of the condensates on the saturation vapor tension curve.
This second factor is then so preponderant over the first one that it allows all restraints resulting from the low NPSH requirement to be avoided and therefore permits not only the use of any type of readmission pump merely compatible with the pressure and the temperature but also the installation of the condensate collecting tank and the said readmission pump without any res-traint regarding the geographical level.
In addition, the pressure prevailing in the condensate collecting tank being very close to the pressure in the boiler, the said pump for direct readmission of the condensates will only have to ensure a hydraulic or delivery head equal to the afore mentioned difference plus the loss of pressure between the pump and the boiler.
Moreover, the small pressure difference between the condensate col-lecting tank and the vapor generating boiler being constant, the readmission pump permanently operates within the same region of its characteristic curve, thus allowing the design characteristics of the said pump to be so selected ~$-~
as to ensure its rnaximum efficiency.
Consequently, this novel conception of -the feeding of boilers with vaporizable liquid permits :
- the use of p~ps of ordinary design irrespective of any required ~PSH, therefore of pumps which are more sturdy and less expensive ;
- the reduction -to a considerable ex-tent of the necessary hydraulic or delivery h~ad, therefore the use of a lower-power pump and driving motor therefor and an impor-tant and corresponding saving of electric power ;
- a more stable operation since the operation of -the pump is permanently within a same region of i-ts characteristic curve.
According to another form of embodiment of the present invention, -the inflow of vaporizable liquid into the boiler takes place without requiring any pump, by means of a collec-ting tank placed above -the va?orizable liquid level of the , said boiler, by directing to the said collecting tank, during - a stage of filling of the latter, the condensa~s at the pressure in the condensat~ return system, and by causing the said collecting tank, forming a distributing lock means, to communicate with the vapor distributing system, during a stage of emptying of the said collecting tank and of return of the condensates to the boiler.
Adv~ntageously, use is made of two such collecting tanks mounted in parallel, in a similar manner, in the downstream portion of the condensate return system, the said two tanks being connected in a similar manner to intakes of vapor at the pressure of -the vapor distributing system, the said two tanks forming two admission lock means wor~ing in opposition, one of them being in the emptying stage while the other is in the filling stage, and vice versa.
As mentioned above, this form of embodiment allows any pump for readmission of the condensa~s into the boiler to be dispensed with.
According to still another form of embodiment of the invention, -the need can be avoided o~ using a feed pu~p, even one opera-ting intermi-tten-tly, to supply vaporizable make-up liquid from a feed -tank to the condensa-te collecting -tank or tanks directly feeding the boiler with vaporizable liquid.
Thus, by combining this last form of embodimen-t with -the s~cond afore-mentioned form of embodiment, the whole plant can be operated without using a power or mechanical pump.
According to this last form of embodiment, the admission of make-up water into the aforesaid collecting tank or tanks is by means of an auxiliary tank placed above the vaporizable liquid level of the said condensate collec-ting tank, the said auxiliary tank being fed, during the stage of filling of the said auxiliary tank, with make-up liquid at a lower pressure than the pressure in the condensate return sys-tem, the make-up fluid con-tained in the said auxiliary tank being -thereafter directed to the said collec-ting tan~, during a stage of emptying of -the said auxiliary tank, by causing the said auxiliary tank, forming an admission lock means, to com-`I municate with the condensate return system.
The inflow of vaporizable liquid into the said auxilia-ry tank is advantageously controlled au-tomatically and in dependence only of the quantity of liquid in the said auxiliary tank, irrespective of the quantity of liquid in the boiler.
Other purposes, objects, characterizing features and advantages of the present invention will appear as the follow-ing non-limitative description proceeds with reference to the appended drawings wherein :
- Figure `1is a diagrammatic view of a closed-circuit plant for producing, distributing and utilizing vapor, with return of the condensates to the boiler, according to the first form of embodiment of the present invention, the said plant employing only two pumps and using a single condensate collec-ting tank si-tuated at any level with respect to the boiler ;
- Figure 2 is a diagrammatic view of a similar plant employing only one purnp for the admission of vaporizable make-up li~uid and using two condensate collecting tanks both of ~hich are located at a higher level than that of the boiler and ;.
_~_ - ~igure 3is a diagrammatic view of a plant similar to that of Figure ~, but in which no pump is used for the admis-sion of vaporizable make-up liquid into the two condensate collecting ta~ks, the said adrnission being by means of an auxiliary tank opera-ting as an admission lock means.
The plant of Figure 1 comprises a vapor-generating boiler 1, a live-vapor distributing system constitu-ted by the main vapor-distributing line 2 and the secondary vapor-distributing lines 3 and 4, a sys-tem for the return of the condensates formed in the consumers supplied with the said live-vapor, the said condensate return system bei.ng constituted essentially by the condensate return line 5 and ~he condensate collecting tank 6, a line 7 for readmission OI the condensates from the collecting tank 6 into the boiler by means of the condensate readrnission pump 8, a certain nurnber of vapor consumers,five in number in the case considered, denoted by the reference letters A1, A2, A3, A4 and A5, a feed tank 9 supplying make-up water to the boiler through the make-up ~ater feed line 10, by means . . .
of the feed pump 11.
The make-up water feed line 10, p.ossibly provided with a valve 12, connects the feed tank 9 with the condensate colle~
ting tank 6, so that no provision is made for direct feeding of the boiler with make-up water, the said make-up water being supplied from the condensate collecting tar~ 6 only through the condensate direct readmission line 7 provided with the valve 13. The pump 11 and the valve 12, if any, are controlled by a regulator 14 connected with a m.ember 15 Ior detecting the height of the water surface in the collecting tank 6 ; the ~al-ve 13 of the condensate readmission line 7 is controlled by a regulator 16 connected with a member 17 for detecting the water level in the boiler 1. The pressure, e~cept for the pressure losses in the line, and the temperature in the live-vapor dis-tributing system are constant, the pressure in this .
system being denoted by P.1 The pressure, except for the pressure losses in the line, and the temperature are constant ~lso in the condensa-te return s~stern, tnis pressure being deno-ted by the reference lette~ P2 ; The-higher pressure P1 is of the order Of, for example, 20 bars, whereas pressure P2 is for $ 3~, ~
' example 17 bars.
According to -the first form of embodimen~t illustrated in Figure 1, the condensa-te collecting tank 6 ~'s directly connected with the live-vapor distributing system -through a v,,apor supply conduit 18, itself connected with the main vapor distributing line 2 ; the conduit 18 is provided with a pressure-reducing valve 19, the function of which is to reduce the pressure P1 by such an amount that the value P3 of the pressure do~mstream of the valve 19 is higher than the pressure corresponding to the temperature of the condensats on the saturation va~or tension curve (pressure of self-,, vaporization of the said condensates). Although the condensate return system is at pressure P2, direct admission of cold water into the collecting tank 6 through the make-up water feed line 10 results in a lowering of the tempera-ture of the condensates in the collecting tank 6, so that the said pressure of self-vaporization within the said collecting tank is a little inferior to the pressure P2.The value of the selected pressure P3 may therefore be equal to pressure P2, e.g. of the - 20 order of 17 bars in the,example considered.
Under such conditions, and as pointed out above, any consideration of geographical height as regards the collecting tank 6 becomes umecessary since the available NPSH is very high and therefore permits the use of a pump 8 of any required NPSH, thus at the same time permitting the avoidance of any tendency-to cavitation and the use of a pump that is sturdy, inexpensive and has the desired output, even if it is very high.
The vapor that is not used in the consumers ~3 to A5 connected to the secondary vapor distributing line 4 cannot flow beyond the -tanks19, which play the role of a limit drain ;
this tank communicates a-t its lower por-tion with -the co~densate return line 5 and the fluid inflow into this line is regula-ted by the valve 20 controlled by the regulator 21 connected to the member 22 for detecting the water le-vel in the tank 19 .
en -t~e valve 20 is open the fluid naturally flo~s into the condensate return system since the pressure P1 acting upon the water surface in the tank 19 is higher than the pressure P2 prevailing i-n the condensa-te return system ; the tank 19 and i-ts accessories therefore constitu-te flo;J lock means of the -type described above.
The connec-tion of consumers A1 and A2 in the system is monotubular, which means that the condensates proceeding from the said consumers flow through the same line as the live vapor, e.g. -through the secondary vapor distributing line 3.
The consumer A1, which is ~or example a heat excha~ger, receives live vapor from -the secondary line 3 through the medium of -the live-vapor supply conduit 23, wheieas the condensates issuing from the consumer A1 are directed to the secondary line 3 through the medium of the condensate ou~let conduit 24 provi-ded with the valve 25 automatically controlled by a regulator 26.
Likewise, the consumer A2 is connected with the secondary vapor distributing line 3 through the li~e-vapor supply conduit 27 and the condensate outlet conduit 28 on which is mounted the valve 29 automatically controlled by the regulator 30.
~- 20 The fluid circulating in the do~mstream portion of line
In both the above cases, use was made, in order to avoid placing the liquid level in the condensate collecting tank at too high a geographical level, of readmission pumps of the low NPSH (i.e. the above-mentioned "required NPSH") type. Such pumps are essentially of the so-called "lateral passage" type based on the principle of semi-volumetric operation. Such pumps are complex in design, very easily damageable, have very small working allowances and are highly expensive. Moreover, they impose very specific and very strict limitations on flow rates, pressures and lay-out. Lastly, their maximum output is limited to values that are incompatible with large-size plants.
In addition, in the present s-tate of the art, two con-curren-t controls of the liquid level in the ~oiler must be performed, namely, a control of the direct readmission of the condensates from the condensate collecting tan~ and a control of the direct admission of make-up water from a feed-tank in-to - the boiler ? -thus complicating the control of the said liquid level and possibly resulting in disturbances in the said con-trol.
All the above considerations have led the Applicant to conceive an installation of the aforesaid type bu-t of a novel design, including a direct readmission of condensates into the boiler. The method according to the present inven-tion, of the type wherein provision is made for direct readmission of condensates from a condensate collecting tank into the vapor generatin~ boiler and wherein a vaporizable make-up liquid is ; supplied to a condensable vapor generating, distributing and utilizing system, for the purpose of vapor production by -the said boiler, is characterized in that the entire quantity of vaporizable make-up liquid is directed to the collecting tank which ensures the whole of the feeding of the boiler with the said vaporizable liquid.
, , Any disturbance in the control of the liquid level in the boiler is -thus avoided since the need for two concurrent controls is eliminated. Indeed, the supply of vaporizable make-up liquid in the plant takes place exclusively at the collecting tank, in case of want of condensates in the la-tter, - i.e. when the quanti-ty of liquid in the collecting tank tends to become too small. In the present specification, the term "quantity of liquid" is used in its broad sense and applies to a mass as well as a volume or a level, and the said quantity ; may be either fixed, possibly zero, or variable.
Thus, according to a characterizing feature of -the pre-sent invention, the inflow of vaporizable liquid into the boiler may be controlled automatically and in such a manner that the water level in -the boiler influences only the direct readmission of the said liquid from the collecting -tank.
According -to another characterizing feature of the present invention, the inflow of vaporizable iiquid into -the boiler from the aforesaid collecting tank is controlled auto-matically in dependence of, exclusively, the water level in the boiler.
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An another advantage of the present inven-tion consists in that, if use is made of a pump, called a feed pump, to supply make-up water to the condensate collecting tank, it is sufficient for such feed-pump to be run intermittently, such runnings being limited to the periodsof time resulting from the regulation of the quantity of liquid in the collecting tank. Consequently, in plants where the make-up liquid constitues only a small portion of the liquid to be admitted to the boiler, electric-power consumption is considerably ; 10 reduced.
According to o~e form of embodiment of the present invention, vapor at maximum pressure is continuously dra~wn from the vapor distributing circuit, and such vapor, possibly after reducing its pressure in a pressure-loss device, is supplied to the aforesaid collecting tank so as to constantly maintain therein a higher pressure than -the pressure corres-: ponding to the temperature of the condensatcs on the vapor tension curve (pressure of self-vaporization).
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This ~orm of embodiment offers the possibility, by using the pump for direct readmission of the condens~es from the said collecting tank into the boiler, of avoiding the ` need for placing the said collecting tank in such a manner that the liquid level therein be permanently at a higher geographical level than that required by the NPSH of the ` pump.
` It is also possible, according to the present invention, to apply a vapor pressure to each liquid surface in the various containers or vessels feeding the tank for collecting all the condensates, the said vapor pressure, which may be either permanent or intermittent, being equal to the pressure in the boiler, except for the pressure losses in the line.
It is therefore possible, irrespective of the various working pressures, temperatures, geographical levels, distan-ces, working hours, rates of flow, controls, and so forth?
for all the condensates in the plant to be gathered in a single collecting tank in which the pressure may be very close to that in the vapor generating boiler. The actual temperature of the condensates in the single collecting tank is the resultant of the mixture of condensates from the various sources. Only the liquid surface layer of a few millimeters in thickness is at a higher temperature as a result of a par-tial condensation of the vapor at high pressure being in contact therewith.
The final mean temperature of the mass of condensates in the single collecting tank is markedly lower than the one corresponding to the then pressure on the saturation vapor tension curve. The NPSH available for the pump for direct readmission of the condensates into the boiler from the said collecting tank is therefore equal to the sum, - of the geographical height (positive or negative) of the liquid level in the tank with respect to the pump suction, and - the height of the imaginary water column representing the dif-ference between the real pressure in the collecting tank and the pressure cor-responding to the temperature of the condensates on the saturation vapor tension curve.
This second factor is then so preponderant over the first one that it allows all restraints resulting from the low NPSH requirement to be avoided and therefore permits not only the use of any type of readmission pump merely compatible with the pressure and the temperature but also the installation of the condensate collecting tank and the said readmission pump without any res-traint regarding the geographical level.
In addition, the pressure prevailing in the condensate collecting tank being very close to the pressure in the boiler, the said pump for direct readmission of the condensates will only have to ensure a hydraulic or delivery head equal to the afore mentioned difference plus the loss of pressure between the pump and the boiler.
Moreover, the small pressure difference between the condensate col-lecting tank and the vapor generating boiler being constant, the readmission pump permanently operates within the same region of its characteristic curve, thus allowing the design characteristics of the said pump to be so selected ~$-~
as to ensure its rnaximum efficiency.
Consequently, this novel conception of -the feeding of boilers with vaporizable liquid permits :
- the use of p~ps of ordinary design irrespective of any required ~PSH, therefore of pumps which are more sturdy and less expensive ;
- the reduction -to a considerable ex-tent of the necessary hydraulic or delivery h~ad, therefore the use of a lower-power pump and driving motor therefor and an impor-tant and corresponding saving of electric power ;
- a more stable operation since the operation of -the pump is permanently within a same region of i-ts characteristic curve.
According to another form of embodiment of the present invention, -the inflow of vaporizable liquid into the boiler takes place without requiring any pump, by means of a collec-ting tank placed above -the va?orizable liquid level of the , said boiler, by directing to the said collecting tank, during - a stage of filling of the latter, the condensa~s at the pressure in the condensat~ return system, and by causing the said collecting tank, forming a distributing lock means, to communicate with the vapor distributing system, during a stage of emptying of the said collecting tank and of return of the condensates to the boiler.
Adv~ntageously, use is made of two such collecting tanks mounted in parallel, in a similar manner, in the downstream portion of the condensate return system, the said two tanks being connected in a similar manner to intakes of vapor at the pressure of -the vapor distributing system, the said two tanks forming two admission lock means wor~ing in opposition, one of them being in the emptying stage while the other is in the filling stage, and vice versa.
As mentioned above, this form of embodiment allows any pump for readmission of the condensa~s into the boiler to be dispensed with.
According to still another form of embodiment of the invention, -the need can be avoided o~ using a feed pu~p, even one opera-ting intermi-tten-tly, to supply vaporizable make-up liquid from a feed -tank to the condensa-te collecting -tank or tanks directly feeding the boiler with vaporizable liquid.
Thus, by combining this last form of embodimen-t with -the s~cond afore-mentioned form of embodiment, the whole plant can be operated without using a power or mechanical pump.
According to this last form of embodiment, the admission of make-up water into the aforesaid collecting tank or tanks is by means of an auxiliary tank placed above the vaporizable liquid level of the said condensate collec-ting tank, the said auxiliary tank being fed, during the stage of filling of the said auxiliary tank, with make-up liquid at a lower pressure than the pressure in the condensate return sys-tem, the make-up fluid con-tained in the said auxiliary tank being -thereafter directed to the said collec-ting tan~, during a stage of emptying of -the said auxiliary tank, by causing the said auxiliary tank, forming an admission lock means, to com-`I municate with the condensate return system.
The inflow of vaporizable liquid into the said auxilia-ry tank is advantageously controlled au-tomatically and in dependence only of the quantity of liquid in the said auxiliary tank, irrespective of the quantity of liquid in the boiler.
Other purposes, objects, characterizing features and advantages of the present invention will appear as the follow-ing non-limitative description proceeds with reference to the appended drawings wherein :
- Figure `1is a diagrammatic view of a closed-circuit plant for producing, distributing and utilizing vapor, with return of the condensates to the boiler, according to the first form of embodiment of the present invention, the said plant employing only two pumps and using a single condensate collec-ting tank si-tuated at any level with respect to the boiler ;
- Figure 2 is a diagrammatic view of a similar plant employing only one purnp for the admission of vaporizable make-up li~uid and using two condensate collecting tanks both of ~hich are located at a higher level than that of the boiler and ;.
_~_ - ~igure 3is a diagrammatic view of a plant similar to that of Figure ~, but in which no pump is used for the admis-sion of vaporizable make-up liquid into the two condensate collecting ta~ks, the said adrnission being by means of an auxiliary tank opera-ting as an admission lock means.
The plant of Figure 1 comprises a vapor-generating boiler 1, a live-vapor distributing system constitu-ted by the main vapor-distributing line 2 and the secondary vapor-distributing lines 3 and 4, a sys-tem for the return of the condensates formed in the consumers supplied with the said live-vapor, the said condensate return system bei.ng constituted essentially by the condensate return line 5 and ~he condensate collecting tank 6, a line 7 for readmission OI the condensates from the collecting tank 6 into the boiler by means of the condensate readrnission pump 8, a certain nurnber of vapor consumers,five in number in the case considered, denoted by the reference letters A1, A2, A3, A4 and A5, a feed tank 9 supplying make-up water to the boiler through the make-up ~ater feed line 10, by means . . .
of the feed pump 11.
The make-up water feed line 10, p.ossibly provided with a valve 12, connects the feed tank 9 with the condensate colle~
ting tank 6, so that no provision is made for direct feeding of the boiler with make-up water, the said make-up water being supplied from the condensate collecting tar~ 6 only through the condensate direct readmission line 7 provided with the valve 13. The pump 11 and the valve 12, if any, are controlled by a regulator 14 connected with a m.ember 15 Ior detecting the height of the water surface in the collecting tank 6 ; the ~al-ve 13 of the condensate readmission line 7 is controlled by a regulator 16 connected with a member 17 for detecting the water level in the boiler 1. The pressure, e~cept for the pressure losses in the line, and the temperature in the live-vapor dis-tributing system are constant, the pressure in this .
system being denoted by P.1 The pressure, except for the pressure losses in the line, and the temperature are constant ~lso in the condensa-te return s~stern, tnis pressure being deno-ted by the reference lette~ P2 ; The-higher pressure P1 is of the order Of, for example, 20 bars, whereas pressure P2 is for $ 3~, ~
' example 17 bars.
According to -the first form of embodimen~t illustrated in Figure 1, the condensa-te collecting tank 6 ~'s directly connected with the live-vapor distributing system -through a v,,apor supply conduit 18, itself connected with the main vapor distributing line 2 ; the conduit 18 is provided with a pressure-reducing valve 19, the function of which is to reduce the pressure P1 by such an amount that the value P3 of the pressure do~mstream of the valve 19 is higher than the pressure corresponding to the temperature of the condensats on the saturation va~or tension curve (pressure of self-,, vaporization of the said condensates). Although the condensate return system is at pressure P2, direct admission of cold water into the collecting tank 6 through the make-up water feed line 10 results in a lowering of the tempera-ture of the condensates in the collecting tank 6, so that the said pressure of self-vaporization within the said collecting tank is a little inferior to the pressure P2.The value of the selected pressure P3 may therefore be equal to pressure P2, e.g. of the - 20 order of 17 bars in the,example considered.
Under such conditions, and as pointed out above, any consideration of geographical height as regards the collecting tank 6 becomes umecessary since the available NPSH is very high and therefore permits the use of a pump 8 of any required NPSH, thus at the same time permitting the avoidance of any tendency-to cavitation and the use of a pump that is sturdy, inexpensive and has the desired output, even if it is very high.
The vapor that is not used in the consumers ~3 to A5 connected to the secondary vapor distributing line 4 cannot flow beyond the -tanks19, which play the role of a limit drain ;
this tank communicates a-t its lower por-tion with -the co~densate return line 5 and the fluid inflow into this line is regula-ted by the valve 20 controlled by the regulator 21 connected to the member 22 for detecting the water le-vel in the tank 19 .
en -t~e valve 20 is open the fluid naturally flo~s into the condensate return system since the pressure P1 acting upon the water surface in the tank 19 is higher than the pressure P2 prevailing i-n the condensa-te return system ; the tank 19 and i-ts accessories therefore constitu-te flo;J lock means of the -type described above.
The connec-tion of consumers A1 and A2 in the system is monotubular, which means that the condensates proceeding from the said consumers flow through the same line as the live vapor, e.g. -through the secondary vapor distributing line 3.
The consumer A1, which is ~or example a heat excha~ger, receives live vapor from -the secondary line 3 through the medium of -the live-vapor supply conduit 23, wheieas the condensates issuing from the consumer A1 are directed to the secondary line 3 through the medium of the condensate ou~let conduit 24 provi-ded with the valve 25 automatically controlled by a regulator 26.
Likewise, the consumer A2 is connected with the secondary vapor distributing line 3 through the li~e-vapor supply conduit 27 and the condensate outlet conduit 28 on which is mounted the valve 29 automatically controlled by the regulator 30.
~- 20 The fluid circulating in the do~mstream portion of line
3 is returned at 31 to the condensate return line 5 through a device 32 constituting a vapor~pump of the type described above.
This vapor pump comprises a tank 33, a condensate outlet conduit 34 provided with a valve 35, a condensa~e inlet conduit 36 provided with a valve 37 and a vapor injection conduit 38 con-nected, on the one hand, with the secondary vapor dis-tributing line 4 at 39, and on the other hand, with the vapor pump through the medium of a three-way valve 40 the third way of which is connected with the line 3 through a piping 41 ; the three way valve 40 and the two-way valves 35 and 37 are con-trolled by servo-motors connected with a regulator 42 receiving the indications of a member 43 for detecting the height of the water level in the tank 33 In a manner known per se, the vapor c~-~r? 32 of Figure l operates in the following manner : the t-.ro-way valve 35 being closed and the three-way valve 40 being so placed as to prevent vapor injection into the line ~8 but to permit the direct pas-sage of -the condensate from the line 3 to the tank 33 ~$~ S
through -the piping 41 and the upstream portion 38a of conduit 38, whereas the two-way valve 37 is open, the condensates may freely en-ter the tank 33 by simple gravity ; when a sufficient level is reached in the tank 33, the regulator 42 acts UpOll the valves 35, 37 and 40 to cause the upstream portion 38b of the condui-t 38 to communicate wi-th the downstream por-tion 38a of this same conduit, the communication with the piping 41 to be cut off and the valves 35 and 37 to be closed. The vapor supplied through the vapor injection conduit 38 is at a pressure P1 of the order of 20 bars, i.e.
superior to the pressure prevailing in tank 33 during its filling, that is to say, to the pressure P4 in the line 3, ~btained by means of the pressure reducer 96), e.g. of the oràer of 10 bars ; on the other hand, the pressure in the condensate outlet condui-t 34 connected at 31 to the condensate return line 5 is the pressure P2, of the order of 17 bars, i.e. a little lower -than pressure P1. As a resul-t, the conden-sates collected in the tank 33 are expelled into the condensate return line 5, and thereafter the opera-ting cycle of the vapor pump 32 may start over again.
The vapor consumer A3 is supplied with vapor at the pressure P1 through the vapor inlet conduit 42. The function of valve 44 is to modulate -the vapor intake into the consumer A3 in dependence of the need for hèa-ted secondary fluid in the said consumer. The pressure dowmstream of the valve 44 is therefore equal or lower than the pressure P1 ~ say P4. The condensate formed in that consumer is recovered by the conden-sate outlet conduit 43 provided with a valve 45. A vapor injec--tion conduit 46 branching off from a poini upstream of the valve 44 comprises an ups'ream portion 45a and a do~mstream portion 46b separated by a three-way valve 47, one of the ways of which is represented by the piping 48 connected with the conduit 43 upstream of the valve 45. The conduits 43 and 46 are connected wi-th the tank 49, as illustrated, -the latter being connected ~.o the condensate outlet condui-t 50 connec-ting with the condensate return line 5 pro~-ided with a valve 51. The -three-i~ray valve 47 and the two-wa~ valves 45 _nd 51 .
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are actua-téd by a regulator 55 connected with the member 52 for detecting the height of the water level wi-thin the tank 49, which, -together wi-th its accessories, cons-titues a - vapor pump 53 whose operation is similar to that of the previously described vapor pump 32.
This vapor pump serves to transfer the condensat~s from the system at the pressure P4 to the condensate return system at the pressure P1 prevailing downstream of the tank 49, on the condensate outlet conduit 50. The vapor pump 53 operates as follows : the valve 51 being closed and the valve 45 being open, the three-way valve 47 is in the position in which the downstream portion 46b of the vapor injection conduit 46 communicates with -the pipe 48, so that the condens~s at the pressure P4 may enter the tank 49 through both the conduit ~- 43 and the pipe 48 and then the downstream portion 46b of conduit 46. When the liquid level within the tank 49 has rea-ched the maximum admissible value, the regulator 55 actuates the mo-torized valves 45, 47 and 5~ to close the valve 45, open the valve 51 and cause the downstream por-tion 46b of the conduit 46 to communicate with the upstream portion 46a OI
that conduit, so that vapor at the pressure P1 is admitted abo~e the water surface in the -tank 49 andexpels the con-densat~s from that tank into the condensate outlet conduit 50, af-ter ~rhich the opera-ting cycle of the vapor pump 53 starts again.
The vapor consumer A4 is supplied through the vapor inlet conduit 56 and the condensate issuing from the consumer A4 is directed to the tank 57 through the condensate outlet conduit 54. The condensa~ from the tank 57 is returned into the con-densate re-turn line 5 through the condensate outlet conduit 58 provided with a valve 59 of the motorized type controlled by the regula-tor 60 connected with the member 61 for detecting the height of the water level in -the tank 57. The tank 57 and its accessories form flow lock means 93 of the type already described. This device operates as follows : when a sufficient quan-ti-ty of water has been admitted into the tank 57 permanen-tly supplied by gravity through the conduit 54 in which the pressurè is P1, -the regulator 60 causes -the valve 59 to open so tha-t the condensates can flow in-to -the outle-t conduit 50 where -the pressure P2 is lower than the pressure P1.
The vapor consumer A5 is supplied through the vapor inlet condui-t 62 on which is placed a pressure-reducing valve 63 which reduces the vapor pressure to a lower value than P1, e.g. -to a value P2 of 17 bars. The condensate outlet conduit 64 provided with a valve 65 is connected w1-th a tank 66 situa-ted at a higher geographical level than the -tank 5j. The out-let line 67 for the condensate from the tank 66 is providedwith a valve 68 and connected with -the tank 57. A vapor injection conduit 69 on which is mounted the three-way valve 70, connects a conduit 67, at a point 71 thereof located bet-ween the valve 70 and the tan~ 57, to the tank 66. One of the pathsof valve 70 is constitu-ted by the pipe 72 connecting with the outle-t conduit 64 upstream of the valve 65. The two-~ath valves 65 and 68 and the three-path valve 70 are motorized ; valves controlled by the regulator 73 and connected wi-~h the member 74 for detecting the height of the water level in -the tank 66. The tank 66 and its accessories constitute an admls-sion lock means 75.
The admission lock means 75 allows the condensates procee-ding from the consumer A5 and at a lower pressure P2 to be periodically admitted into a vessel where the pressure P1 is higher, i.e., in the case considered, the tank 57. Thls ad-mission lock means operates as follows : the valve 68 being closed, the valve 65 being open, the three-way valve 70 is in the position allowing the pipe 72 to communicate with the downstream portion 69b of the vapor injection conduit &9, thus ~o permitting the filling of the a~mission lock means 75, on the one hand, through the condensate ou-tlet conduit 6L~, and on the other hand, through the piping 72 and the downstream portion 69b of the vapor injection conduit 69. When -the filling stage is over, the regu]ator 73 causes the valve 65 to close, the ~alve 68 to open and the three-way valve 70~-to be switched so as to allow both portlons 69a and 69b of conduit 69 to commu-nicate wi-th one another. The same pressure P1 is then applied :
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to bo-th sides of the mass of wa-ter in the tank 66, so tha-t, owing to the difference in geographical level between the tank 66 and the tank 67, this water may flow in-to the tank 57 through the condensateou-tlet conduit 67. When this ~illing s-tage is completed, the operating cycle of the admission lock means 75 may start again.
The plan-t according to the form of embodimen-t illustrated in ~igure 2comprises a feed tank 9', the vapor genera-ting boiler 1' and its main vapor distributing line 2', the main condensate return line 5', the two general condensate collecti~g tanks 6'a and 6'b and the condensate direc-t readmission line 7' constituted by the condensate outle-t conduit 7'a from the tank 6'a and the condensate outlet conduit 7'b from -the tank 6'b. The vapor consumers connected either to the vapor dis-tributing system supplied through the line 2' (of monotubular type) or between this system and the condensate return system supplying the line 5' are not sho~m in Figure 2. The reference numeral 76 denotes a line for the injection of vapor at the pressure P1 prevailing in the vapor distributing system, which line branches out into a conduit 76a for vapor injection into the tank 6'a, and into a conduit 76b for vapor injection into the tank 6'b, these conduits being provided with three-way valves ~7a and 77b, respectively. The condensate return line 5' is connected with the tanks 6'a and 6'b -through condensate inlet conduits 78a and 78b, respectively, each provided with a valve 79a and 79b, respectively. Furthermore, the condensate return line 5' is connected with the vapor injection line 76 through a conduit 18' provided with a pressure-loss device such as a pressure reducing valve 19'.
The feed tank 9' is connected with the collecting tanks 6'a and 6'b through the make-up water feed line 10' on which is mounted the feed pump 11' and which branches out into a feed conduit 11'a leading to tne tank 6'a and provided wi-th the valve 12'a, and into a feed conduit 11'b leading to the tank 6'b and provided with the valve 12'b. The feed pump 11' operates continuously, but the feeding of the tanks 6'a and 6'b, which takes place interr..ittently, is controlled by the val~res 12'a and 12'b, which are motorized valves con-trolled by the regulators 1L~la and 1~'b, respectively, connected with thr wa-ter level de-tectors 15'a and 15'b, respectively, so -that one of these valves opens in case of want of water in the tank which, at the instant considered, is feeding the boiler.
Direct readmission of the condensates into the vapor genera-ting boiler 1' is con-trolled by the motorized valve 13', itself controlled by the regulator 16' connected with the member 17' for detecting the ~ATater level in -the boiler.
Whereas in the plant of Figure 1 the condensate collec-ting tank ~ can permanen-tly receive condensates through the condensate return line, the filling of each tank such as 6'a or 6'b lasts only part of its operating time, the operating cycle of each of these tanks comprising a filling stage followed by an emptying stage or a boiler water-feeding stage, ' the operating cycles of -the two tanks being so shifted with respect to one another that ~hen one of them is being filled the other is being emptied and vice versa. To this end, the three-way va] ves 77a and 77b and the two-way valves 79a and 79b, as well as the two-way valves 80a and 80b mounted on the condensate outlet conduits 7'a and 7'b, respectively, are motorized valves controlled by the control reversing relay 81 - and the regulators 82a and 82b, the first of which is connec-ted to a member 83a ~or detecting the max~mum water-level and ~ - to a member ~4a for detecting the mini;num water-level in the ' tank 6'a, whereas the second is connected to a member 83b for detecting the maximum water-level and to a member 84b for detecting the minimum-water level in the tank 6'b. The ' 30 reversing of the control reversing relay 81 takes place when the tank 6'a or 6'b being filled becomes full.
The tan!~s 6'a and 5'b and their accessories operate as t~o adrnission lock means, respectively, one of which is being filled while the other is being emptied and'vice versa. During the stage of filling of the tank of one of the said lock means, the inlet conduil; 78a or 78b, respectively, for the condensates - at the pressure P2 serves to admit the condènsates into the ~ --17--e ~
tank considered ; thus, if the tank 6'a is the one in the filling posi-tion, the valve 79ais open and the valve 80a is closed, whereas the injection of vapor at the pressure P1 into the tank G'a from the line 76 is prevented by the three-way valve 77a ; during the stage of emptying of the same tank 6'a, the valve 79a is closed and the valve 80a is open, whereas the three-way valve 77a is in a:position allowing vapor..at pressure P1 to be supplied to the tank 6'a through the vapor injection line 76 and the vapor injection conduit 76a. Each of the -tanks 6'a and 6''b is si-tua-ted at a higher geographical level than that of the boiler 1l, so that th.is difference in geographical level is sufficient, during the emptying stage, to force the water under pressure P1 present in the tank being emptied into the line 7' for the readmission of -the condensate~ also at the pressure P1. It will be noted t~at the pressure in each tank such as 6'a and 6'b is alterna-tely at the value P1 or P2~ one of the said tanks being at the pressure P1 while -the other is at the pressure P2 and vice ver-. sa. Such a plant allows all the pumps for direct readmission of the condensates into the boiler to be dispensed with. In this form of embodiment, however, the need for the feed pump 11', the operation of which may be either continuous, as in' the example represen-ted, or intermittent, is due to the selec- .
ted method of make-up water admission.
In the form of embodimen-t of Figure 3, the same devices as in Figure 2 are seen, ~the corresponding devices being denoted by the same reference numer~s accompanied by the sign "second" instead of the sign "prime".
: In addition, the feed pump is eliminated and replaced 30 by admission lock means denoted generally by the reference numeral 85. Theseadmission loc~ means are essentially consti-tuted by a tank 86 supplied with make-up water -through a :
make-up water admission line 87, the emptying of this tank taking place through a make-up water feed line 10" l'eading to the tanks 6'a and 6Ib and provided with a two-way valve 89.
The tank 86 is also connected with the line 2" for the supply of vapor at the pressure P1 through the line 90b connec~ed h~
wi-th the three way valve 91 and with which is also connected the piping 92 connec-ted upstream of the two way valve 88. The valves 88, 89 and 91 are mo-torized valves con-trolled by the regulator 93 connected with a member 94 for detecting the ma~imum water level in the tank 86 and with a member 95 for detec-ting -the minimum water level in the same tank.
The operating cycle of -the admissio~ ~ock means 85 comprises a stage of filling of -the -tank ~ a t -the pressure PO prevailing inthe feed tank 9", -through the make-up water admission line ~37, the valve 88 being open and the valve 89 ~eing closed, ~rrhile -the three-~ay valve 91 allows -the piping ~2 to communicate wi-th the downstream portion 90a of the .
condensate supply condui-t 90. In the stage of emptying of the tank 86, the pressure in the latter is brought to the value P1 higher thant the pressure PO. After closing the valve 88, opening -the valve 89 and switching the valve 91 to allow -the downstream portion 90a of the condensate supply conduit 90 to communica-te with its upstream portion 90b. On the other hand, the tank 86 is situated at a higher geographical level 20 than the tanks 6"a and 6~b, thus permi-tting, during this emptying stage, the flow of liquid from the tank 86, at the pressure P1, into the line 10" for feeding the tanks 6"a and 6"b with make-up water, which line 10" also is at the pressure P1. It will be noted that check valves 96a and 96b, respec-tively~ are mounted on the make-up water feed conduit 11'a and 11 'b, respectively, upstream of the valves 12"a and 12"b, respectively, provided on those conduits.
As in the case of Figure 2, the tank 6'a or 6'b which is fed with make-up water is the one which, at the instant 30 considered, is feeding the boiler.
It will be observed tha-t the plant of Figure 3 eliminates the need for any mechanical or power pump owing to a systematic use of the motive force of vapor, bo-th of the vapor distributing circui-t and the circuit for the return of the condensates to the boiler, and to a judicious predetermina-tion of the respective leve]s of the make-up water admission lock means and -the condensate collecting tanks, between the w low point o~ the plant represented by -tne boiler and the high point represen-ted by the feed tank.
Of course the presen-t inven-tion is by no means limited to the forms of embodiment described and illustrated which have been given by way of example only. In par-ticular, it comprises all -technical means equiv~lent -to the means des-cribed, as well as -their combinations, should -the la-t-ter be carried ou-t according to its gist and usedwithin -the scope of -the following claims.
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This vapor pump comprises a tank 33, a condensate outlet conduit 34 provided with a valve 35, a condensa~e inlet conduit 36 provided with a valve 37 and a vapor injection conduit 38 con-nected, on the one hand, with the secondary vapor dis-tributing line 4 at 39, and on the other hand, with the vapor pump through the medium of a three-way valve 40 the third way of which is connected with the line 3 through a piping 41 ; the three way valve 40 and the two-way valves 35 and 37 are con-trolled by servo-motors connected with a regulator 42 receiving the indications of a member 43 for detecting the height of the water level in the tank 33 In a manner known per se, the vapor c~-~r? 32 of Figure l operates in the following manner : the t-.ro-way valve 35 being closed and the three-way valve 40 being so placed as to prevent vapor injection into the line ~8 but to permit the direct pas-sage of -the condensate from the line 3 to the tank 33 ~$~ S
through -the piping 41 and the upstream portion 38a of conduit 38, whereas the two-way valve 37 is open, the condensates may freely en-ter the tank 33 by simple gravity ; when a sufficient level is reached in the tank 33, the regulator 42 acts UpOll the valves 35, 37 and 40 to cause the upstream portion 38b of the condui-t 38 to communicate wi-th the downstream por-tion 38a of this same conduit, the communication with the piping 41 to be cut off and the valves 35 and 37 to be closed. The vapor supplied through the vapor injection conduit 38 is at a pressure P1 of the order of 20 bars, i.e.
superior to the pressure prevailing in tank 33 during its filling, that is to say, to the pressure P4 in the line 3, ~btained by means of the pressure reducer 96), e.g. of the oràer of 10 bars ; on the other hand, the pressure in the condensate outlet condui-t 34 connected at 31 to the condensate return line 5 is the pressure P2, of the order of 17 bars, i.e. a little lower -than pressure P1. As a resul-t, the conden-sates collected in the tank 33 are expelled into the condensate return line 5, and thereafter the opera-ting cycle of the vapor pump 32 may start over again.
The vapor consumer A3 is supplied with vapor at the pressure P1 through the vapor inlet conduit 42. The function of valve 44 is to modulate -the vapor intake into the consumer A3 in dependence of the need for hèa-ted secondary fluid in the said consumer. The pressure dowmstream of the valve 44 is therefore equal or lower than the pressure P1 ~ say P4. The condensate formed in that consumer is recovered by the conden-sate outlet conduit 43 provided with a valve 45. A vapor injec--tion conduit 46 branching off from a poini upstream of the valve 44 comprises an ups'ream portion 45a and a do~mstream portion 46b separated by a three-way valve 47, one of the ways of which is represented by the piping 48 connected with the conduit 43 upstream of the valve 45. The conduits 43 and 46 are connected wi-th the tank 49, as illustrated, -the latter being connected ~.o the condensate outlet condui-t 50 connec-ting with the condensate return line 5 pro~-ided with a valve 51. The -three-i~ray valve 47 and the two-wa~ valves 45 _nd 51 .
.
. , .
' ,:
are actua-téd by a regulator 55 connected with the member 52 for detecting the height of the water level wi-thin the tank 49, which, -together wi-th its accessories, cons-titues a - vapor pump 53 whose operation is similar to that of the previously described vapor pump 32.
This vapor pump serves to transfer the condensat~s from the system at the pressure P4 to the condensate return system at the pressure P1 prevailing downstream of the tank 49, on the condensate outlet conduit 50. The vapor pump 53 operates as follows : the valve 51 being closed and the valve 45 being open, the three-way valve 47 is in the position in which the downstream portion 46b of the vapor injection conduit 46 communicates with -the pipe 48, so that the condens~s at the pressure P4 may enter the tank 49 through both the conduit ~- 43 and the pipe 48 and then the downstream portion 46b of conduit 46. When the liquid level within the tank 49 has rea-ched the maximum admissible value, the regulator 55 actuates the mo-torized valves 45, 47 and 5~ to close the valve 45, open the valve 51 and cause the downstream por-tion 46b of the conduit 46 to communicate with the upstream portion 46a OI
that conduit, so that vapor at the pressure P1 is admitted abo~e the water surface in the -tank 49 andexpels the con-densat~s from that tank into the condensate outlet conduit 50, af-ter ~rhich the opera-ting cycle of the vapor pump 53 starts again.
The vapor consumer A4 is supplied through the vapor inlet conduit 56 and the condensate issuing from the consumer A4 is directed to the tank 57 through the condensate outlet conduit 54. The condensa~ from the tank 57 is returned into the con-densate re-turn line 5 through the condensate outlet conduit 58 provided with a valve 59 of the motorized type controlled by the regula-tor 60 connected with the member 61 for detecting the height of the water level in -the tank 57. The tank 57 and its accessories form flow lock means 93 of the type already described. This device operates as follows : when a sufficient quan-ti-ty of water has been admitted into the tank 57 permanen-tly supplied by gravity through the conduit 54 in which the pressurè is P1, -the regulator 60 causes -the valve 59 to open so tha-t the condensates can flow in-to -the outle-t conduit 50 where -the pressure P2 is lower than the pressure P1.
The vapor consumer A5 is supplied through the vapor inlet condui-t 62 on which is placed a pressure-reducing valve 63 which reduces the vapor pressure to a lower value than P1, e.g. -to a value P2 of 17 bars. The condensate outlet conduit 64 provided with a valve 65 is connected w1-th a tank 66 situa-ted at a higher geographical level than the -tank 5j. The out-let line 67 for the condensate from the tank 66 is providedwith a valve 68 and connected with -the tank 57. A vapor injection conduit 69 on which is mounted the three-way valve 70, connects a conduit 67, at a point 71 thereof located bet-ween the valve 70 and the tan~ 57, to the tank 66. One of the pathsof valve 70 is constitu-ted by the pipe 72 connecting with the outle-t conduit 64 upstream of the valve 65. The two-~ath valves 65 and 68 and the three-path valve 70 are motorized ; valves controlled by the regulator 73 and connected wi-~h the member 74 for detecting the height of the water level in -the tank 66. The tank 66 and its accessories constitute an admls-sion lock means 75.
The admission lock means 75 allows the condensates procee-ding from the consumer A5 and at a lower pressure P2 to be periodically admitted into a vessel where the pressure P1 is higher, i.e., in the case considered, the tank 57. Thls ad-mission lock means operates as follows : the valve 68 being closed, the valve 65 being open, the three-way valve 70 is in the position allowing the pipe 72 to communicate with the downstream portion 69b of the vapor injection conduit &9, thus ~o permitting the filling of the a~mission lock means 75, on the one hand, through the condensate ou-tlet conduit 6L~, and on the other hand, through the piping 72 and the downstream portion 69b of the vapor injection conduit 69. When -the filling stage is over, the regu]ator 73 causes the valve 65 to close, the ~alve 68 to open and the three-way valve 70~-to be switched so as to allow both portlons 69a and 69b of conduit 69 to commu-nicate wi-th one another. The same pressure P1 is then applied :
: .
2 ~ ~
to bo-th sides of the mass of wa-ter in the tank 66, so tha-t, owing to the difference in geographical level between the tank 66 and the tank 67, this water may flow in-to the tank 57 through the condensateou-tlet conduit 67. When this ~illing s-tage is completed, the operating cycle of the admission lock means 75 may start again.
The plan-t according to the form of embodimen-t illustrated in ~igure 2comprises a feed tank 9', the vapor genera-ting boiler 1' and its main vapor distributing line 2', the main condensate return line 5', the two general condensate collecti~g tanks 6'a and 6'b and the condensate direc-t readmission line 7' constituted by the condensate outle-t conduit 7'a from the tank 6'a and the condensate outlet conduit 7'b from -the tank 6'b. The vapor consumers connected either to the vapor dis-tributing system supplied through the line 2' (of monotubular type) or between this system and the condensate return system supplying the line 5' are not sho~m in Figure 2. The reference numeral 76 denotes a line for the injection of vapor at the pressure P1 prevailing in the vapor distributing system, which line branches out into a conduit 76a for vapor injection into the tank 6'a, and into a conduit 76b for vapor injection into the tank 6'b, these conduits being provided with three-way valves ~7a and 77b, respectively. The condensate return line 5' is connected with the tanks 6'a and 6'b -through condensate inlet conduits 78a and 78b, respectively, each provided with a valve 79a and 79b, respectively. Furthermore, the condensate return line 5' is connected with the vapor injection line 76 through a conduit 18' provided with a pressure-loss device such as a pressure reducing valve 19'.
The feed tank 9' is connected with the collecting tanks 6'a and 6'b through the make-up water feed line 10' on which is mounted the feed pump 11' and which branches out into a feed conduit 11'a leading to tne tank 6'a and provided wi-th the valve 12'a, and into a feed conduit 11'b leading to the tank 6'b and provided with the valve 12'b. The feed pump 11' operates continuously, but the feeding of the tanks 6'a and 6'b, which takes place interr..ittently, is controlled by the val~res 12'a and 12'b, which are motorized valves con-trolled by the regulators 1L~la and 1~'b, respectively, connected with thr wa-ter level de-tectors 15'a and 15'b, respectively, so -that one of these valves opens in case of want of water in the tank which, at the instant considered, is feeding the boiler.
Direct readmission of the condensates into the vapor genera-ting boiler 1' is con-trolled by the motorized valve 13', itself controlled by the regulator 16' connected with the member 17' for detecting the ~ATater level in -the boiler.
Whereas in the plant of Figure 1 the condensate collec-ting tank ~ can permanen-tly receive condensates through the condensate return line, the filling of each tank such as 6'a or 6'b lasts only part of its operating time, the operating cycle of each of these tanks comprising a filling stage followed by an emptying stage or a boiler water-feeding stage, ' the operating cycles of -the two tanks being so shifted with respect to one another that ~hen one of them is being filled the other is being emptied and vice versa. To this end, the three-way va] ves 77a and 77b and the two-way valves 79a and 79b, as well as the two-way valves 80a and 80b mounted on the condensate outlet conduits 7'a and 7'b, respectively, are motorized valves controlled by the control reversing relay 81 - and the regulators 82a and 82b, the first of which is connec-ted to a member 83a ~or detecting the max~mum water-level and ~ - to a member ~4a for detecting the mini;num water-level in the ' tank 6'a, whereas the second is connected to a member 83b for detecting the maximum water-level and to a member 84b for detecting the minimum-water level in the tank 6'b. The ' 30 reversing of the control reversing relay 81 takes place when the tank 6'a or 6'b being filled becomes full.
The tan!~s 6'a and 5'b and their accessories operate as t~o adrnission lock means, respectively, one of which is being filled while the other is being emptied and'vice versa. During the stage of filling of the tank of one of the said lock means, the inlet conduil; 78a or 78b, respectively, for the condensates - at the pressure P2 serves to admit the condènsates into the ~ --17--e ~
tank considered ; thus, if the tank 6'a is the one in the filling posi-tion, the valve 79ais open and the valve 80a is closed, whereas the injection of vapor at the pressure P1 into the tank G'a from the line 76 is prevented by the three-way valve 77a ; during the stage of emptying of the same tank 6'a, the valve 79a is closed and the valve 80a is open, whereas the three-way valve 77a is in a:position allowing vapor..at pressure P1 to be supplied to the tank 6'a through the vapor injection line 76 and the vapor injection conduit 76a. Each of the -tanks 6'a and 6''b is si-tua-ted at a higher geographical level than that of the boiler 1l, so that th.is difference in geographical level is sufficient, during the emptying stage, to force the water under pressure P1 present in the tank being emptied into the line 7' for the readmission of -the condensate~ also at the pressure P1. It will be noted t~at the pressure in each tank such as 6'a and 6'b is alterna-tely at the value P1 or P2~ one of the said tanks being at the pressure P1 while -the other is at the pressure P2 and vice ver-. sa. Such a plant allows all the pumps for direct readmission of the condensates into the boiler to be dispensed with. In this form of embodiment, however, the need for the feed pump 11', the operation of which may be either continuous, as in' the example represen-ted, or intermittent, is due to the selec- .
ted method of make-up water admission.
In the form of embodimen-t of Figure 3, the same devices as in Figure 2 are seen, ~the corresponding devices being denoted by the same reference numer~s accompanied by the sign "second" instead of the sign "prime".
: In addition, the feed pump is eliminated and replaced 30 by admission lock means denoted generally by the reference numeral 85. Theseadmission loc~ means are essentially consti-tuted by a tank 86 supplied with make-up water -through a :
make-up water admission line 87, the emptying of this tank taking place through a make-up water feed line 10" l'eading to the tanks 6'a and 6Ib and provided with a two-way valve 89.
The tank 86 is also connected with the line 2" for the supply of vapor at the pressure P1 through the line 90b connec~ed h~
wi-th the three way valve 91 and with which is also connected the piping 92 connec-ted upstream of the two way valve 88. The valves 88, 89 and 91 are mo-torized valves con-trolled by the regulator 93 connected with a member 94 for detecting the ma~imum water level in the tank 86 and with a member 95 for detec-ting -the minimum water level in the same tank.
The operating cycle of -the admissio~ ~ock means 85 comprises a stage of filling of -the -tank ~ a t -the pressure PO prevailing inthe feed tank 9", -through the make-up water admission line ~37, the valve 88 being open and the valve 89 ~eing closed, ~rrhile -the three-~ay valve 91 allows -the piping ~2 to communicate wi-th the downstream portion 90a of the .
condensate supply condui-t 90. In the stage of emptying of the tank 86, the pressure in the latter is brought to the value P1 higher thant the pressure PO. After closing the valve 88, opening -the valve 89 and switching the valve 91 to allow -the downstream portion 90a of the condensate supply conduit 90 to communica-te with its upstream portion 90b. On the other hand, the tank 86 is situated at a higher geographical level 20 than the tanks 6"a and 6~b, thus permi-tting, during this emptying stage, the flow of liquid from the tank 86, at the pressure P1, into the line 10" for feeding the tanks 6"a and 6"b with make-up water, which line 10" also is at the pressure P1. It will be noted that check valves 96a and 96b, respec-tively~ are mounted on the make-up water feed conduit 11'a and 11 'b, respectively, upstream of the valves 12"a and 12"b, respectively, provided on those conduits.
As in the case of Figure 2, the tank 6'a or 6'b which is fed with make-up water is the one which, at the instant 30 considered, is feeding the boiler.
It will be observed tha-t the plant of Figure 3 eliminates the need for any mechanical or power pump owing to a systematic use of the motive force of vapor, bo-th of the vapor distributing circui-t and the circuit for the return of the condensates to the boiler, and to a judicious predetermina-tion of the respective leve]s of the make-up water admission lock means and -the condensate collecting tanks, between the w low point o~ the plant represented by -tne boiler and the high point represen-ted by the feed tank.
Of course the presen-t inven-tion is by no means limited to the forms of embodiment described and illustrated which have been given by way of example only. In par-ticular, it comprises all -technical means equiv~lent -to the means des-cribed, as well as -their combinations, should -the la-t-ter be carried ou-t according to its gist and usedwithin -the scope of -the following claims.
' .
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a method for feeding vaporizable liquid to a system for producing, distributing and utilizing condensable vapor wherein the system includes at least one boiler, a vapor dis-tributing system having a point of vapor supply and at least one point of mechanical condensate discharge, a condensate return system including at least one buffer tank for holding and temp-orarily storing all the condensates for return to the said boiler and a source of vaporizable make-up liquid for supplying said system, the method including the steps of producing vapor in the boiler in a closed loop circulation at a substantially constant temperature and pressure except for pressure losses, on the one hand, in the vapor distributing system between the vapor supply point and at least one of the mechanical condensate discharge points, and on the other hand, in the condensate return system between the point of discharge and at least one of the buffer tanks, with a pressure in the condensate return system no higher than the pressure in the vapor distributing system and effecting return of the condensates to the boiler under at least one of gravitational force and the motive action of the vapor within said system, and the improvement comprising the step of directing all the vaporizable make-up liquid to the collecting tank to supply the boiler with its total vaporizable liquid requirement, and the step of continuously drawing vapor at maximum pressure from the vapor distributing system and supplying said vapor to the said collecting tank permanently to maintain therein a higher pressure than the pressure on the saturation vapor tension curve which corresponds to the temperature of the condensates.
2. A method according to claim 1, wherein the intake of vaporizable make-up liquid into the said system is controlled automatically and takes place in such a manner that the water level in the boiler governs only the direct reintroduction of the said liquid into the boiler from the collecting tank.
3. A method according to claim 1, wherein the intake of vaporizable liquid into the boiler from the said collecting tank is controlled automatically and takes place in dependence only of the water level in the boiler.
4. A method according to claim 1, wherein the intake of vaporizable liquid to the boiler takes place, without requiring the use of any mechanical or power pump, by means of a collecting tank situated above the vaporizable liquid level in the boiler, by directing into the said tank, during a stage of filling of the latter, the condensates at the pressure in the condensate return system and by allowing the said collecting tank, forming a distrib-uting lock means, to communicate with the vapor distributing sys-tem during a stage of emptying of the said collecting tank and of return of the condensates to the boiler.
5. A method according to claim 4, wherein use is made of two collecting tanks mounted in parallel and in a similar manner in the downstream portion of the condensate return system and connected in a similar manner with intake of vapor at the pressure in the vapor distributing system, the said two tanks forming two distributing lock means working in opposition in such a manner that while one of them is in the emptying stage the other is in the filling stage and vice versa, such reversing of stages being preferably brought about when the tank which is in the fill-ing stage is full.
6. A method according to claim 1, wherein the re-admission of vaporizable make-up liquid into the said collecting tank takes place, without requiring the use of any mechanical or power pump, by means of an auxiliary tank situated above the vapor-izable liquid level in the said condensate collecting tank, the said auxiliary tank being fed, during a stage of filling of the said auxiliary tank, with make-up liquid at a lower pressure than the pressure prevailing in the condensate return system, the make-up fluid contained in the said auxiliary tank being there-after directed to the said collecting tank or tanks, during a stage of emptying of the said auxiliary tank, by allowing the said auxil-iary tank to communicate with the vapor distributing system.
7. A method according to claim 6, wherein the intake of vaporizable liquid into the said auxiliary tank is controlled automatically and takes place only in dependence of the quantity of liquid in the said auxiliary tank.
8. A method according to claim 5, wherein the intake of vaporizable make-up liquid into the system takes place only in whichever of the two said collecting tanks that is in the empty-ing stage.
9. A method according to claim 1, wherein the pressure of said drawn vapor is reduced in a pressure-loss device prior to feeding of the drawn vapor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7801773A FR2415263A2 (en) | 1975-03-13 | 1978-01-23 | Steam generator system containing boiler - has distribution network for supply and return of steam controlled automatically |
| FR7801773 | 1978-01-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1115145A true CA1115145A (en) | 1981-12-29 |
Family
ID=9203730
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA319,774A Expired CA1115145A (en) | 1978-01-23 | 1979-01-17 | Method and device for feeding a system for generating and distributing vapor condensable into make-up liquid |
Country Status (11)
| Country | Link |
|---|---|
| JP (1) | JPS54155301A (en) |
| AU (1) | AU4350179A (en) |
| BE (1) | BE873496A (en) |
| BR (1) | BR7900279A (en) |
| CA (1) | CA1115145A (en) |
| CH (1) | CH634393A5 (en) |
| ES (1) | ES477017A1 (en) |
| GB (1) | GB2017277B (en) |
| IT (1) | IT1166241B (en) |
| MX (1) | MX148641A (en) |
| NL (1) | NL7900473A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4603685A (en) * | 1983-06-21 | 1986-08-05 | Institut National De La Recherche Scientifique | Solar heating system |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60140004A (en) * | 1983-12-27 | 1985-07-24 | 小幡 福治 | Recovery device for drain from boiler |
-
1979
- 1979-01-11 GB GB7901118A patent/GB2017277B/en not_active Expired
- 1979-01-15 MX MX176289A patent/MX148641A/en unknown
- 1979-01-16 BR BR7900279A patent/BR7900279A/en unknown
- 1979-01-16 BE BE192911A patent/BE873496A/en unknown
- 1979-01-16 IT IT46805/79A patent/IT1166241B/en active
- 1979-01-17 CH CH45079A patent/CH634393A5/en not_active IP Right Cessation
- 1979-01-17 CA CA319,774A patent/CA1115145A/en not_active Expired
- 1979-01-19 NL NL7900473A patent/NL7900473A/en not_active Application Discontinuation
- 1979-01-19 ES ES477017A patent/ES477017A1/en not_active Expired
- 1979-01-19 AU AU43501/79A patent/AU4350179A/en not_active Abandoned
- 1979-01-23 JP JP650079A patent/JPS54155301A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4603685A (en) * | 1983-06-21 | 1986-08-05 | Institut National De La Recherche Scientifique | Solar heating system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS54155301A (en) | 1979-12-07 |
| IT7946805A0 (en) | 1979-01-16 |
| GB2017277A (en) | 1979-10-03 |
| IT1166241B (en) | 1987-04-29 |
| GB2017277B (en) | 1982-06-23 |
| NL7900473A (en) | 1979-07-25 |
| AU4350179A (en) | 1979-08-02 |
| CH634393A5 (en) | 1983-01-31 |
| ES477017A1 (en) | 1979-10-16 |
| MX148641A (en) | 1983-05-20 |
| BR7900279A (en) | 1979-08-14 |
| BE873496A (en) | 1979-05-16 |
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Legal Events
| Date | Code | Title | Description |
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| MKEX | Expiry | ||
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