WO1994009326A1 - Mixing and heat-exchange system for condensing gas boilers - Google Patents

Abstract

The invention pertains to a device consisting of a combustion chamber (12) and, situated at its upper surface, a mixing chamber (6), with a gas burner panel (11), and of a heat exchanger enclosed in the lower part of the combustion chamber. The mixer (1) is placed between gas and air feed lines and the mixing chamber (6) and made with a surrounding chamber (3), while near the critical inside diameter of the mixer there is a ring of at least three symetrically penetrating nozzles (5). The mixer feeds into the mixing chamber (6), which consists of the preparation sector (8) and the feed-line sector (7) comprising at least one feed partition (10) and a section wall (100). At the base of the combustion chamber there is at least one ribbed tube (14) with one end in the combustion chamber (12) and the other at the base of the descending channel (15). Between the descending channel wall and the combustion chamber wall there is a descending channel (17) linked with the mixer (1) via communication of the junction channel (22) with ventilator (21).

Description

 MIXING AND WARM EXCHANGING SYSTEM ON CONDENSING GAS BOILERS

Technical part

The invention is in the field of heating systems and is a device which heats up for water and other media and which consists of supply and other connection fittings, consisting of the combustion chamber with a flat gas burner and with mixing chamber components, one above the other. if the mixing chamber has a mixer in line with the peripheral chamber. A heat exchanger for cooling the combustion products and simultaneously reducing the flow of the combustion air is connected to the lower part of the combustion chamber.

Current state of the art

The condensation units of this type, used in particular for low-volume room heating, and a surface burner in various mold lead-throughs and room arrangements, have relatively high effectiveness and small pollutant emissions from the combustion process run, especially NO _χ , CO _χ and SO _χ ¬ are realistic. One of the conditions for satisfactory surface burner work is complete homogenization of the fuel mixture and uniform, continuous distribution of the heating mixture to the entire burner active area. After the combustion process is complete, hot combustion products pass through a combustion chamber, where water vapor condensation and heat transfer between the surfaces pass through the heat exchanger. Then cooling combustion products are leading into aggregate space, e.g. B. in chimney.

Between the examples, the solutions primarily include a mixing chamber in the form of a truncated pyramid, the subsurface of which is created by a surface gas burner. Air entering this mixing chamber is supplied with the fan, which is located vertically on the upper ground plane. There is a lamella in the mixing chamber in the vicinity of the inlet opening for air; it is parallel to the burner surface and introduces the gas that enters it into a turbulent barrel. The gas device to the opposite position tion to the air inlet.

Plain, large-area burner of ceramic with a flame is also suitable as a combustion chamber wall part if the combustion chamber is in a tabular cuboid shape; The heating mixture is homogenized in the fan chamber and leads into the combustion chamber through an opening in the top level from the fan.

Another known construction which uses heating mixture homogenization up to the area of the combustion chamber with the cylindrical burners of refractory steel; on the burner surface the micro nozzles for the heating mixture passage are made and the combustion chamber also has a cylindrical shape, its inner surface creating a spiral pipe with heated media.

Between known solutions also circular burners with independent gas entry and with independent combustion oil entry are heard; primary combustion air is sucked in through the independent openings in the upper surface of the burner and this burner lies in the underground level of the combustion chamber. Secondary combustion air is led through openings in the outer circumference of the burner. On the side wall surface, which is opposite the gas and air inlet, the surface burner has the shape of the cylinder section.

Tabular cuboid shape with convex central taper, the axis of this taper being approximately perpendicular to gas and

Air devices in flat interior areas of the chamber; further nozzles with lamellae concavely narrowed chamber middle part form further known device.

Described construction solutions of the condensation gas boilers have several typical shortcomings, each device having a minimal disadvantage. Such boilers have relatively large mixing chambers and heating mixture homogenization has persistent shortages; Another flaw is the relatively high temperature of the combustion products, which run in the atmosphere and which is around level 80 ^* C, which is good evidence of further possibilities for heat exchange improvements. The result of this reality is that there are further inadequacies for eliminating or lowering existing errors, for example possibilities for lowering pollutant emissions, better heating mixture homogenization, etc

The essence of invention

The above-mentioned deficiency eliminates the advantages of the mixing and heat exchange system of the condensing gas boiler according to the invention. The essential part is that it consists of supply fittings, connecting fittings with the control, regulation and indication part, from the mixer with the mixing chamber and there is a surface gas burner. The surface gas burner creates part of the surface of the combustion chamber part; The heat exchanger is connected to the lower part of the combustion chamber, in which the combustion products are cooled and at the same time pre-heated by the combustion air. The mixer is manufactured as a Venturi tube with an axial feed line for compressed (e.g. with the help of the fan) combustion air. After the outer surface of the mixer, the peripheral chamber, with its inner surfaces, is profiled as a hollow rotary body and provides radial gas supply. The interior of the mixer and the interior of the circumference are close to one another in the vicinity of the critical diameter with circumferential nozzles that pierce. The circumferential nozzles are a minimum of three and symmetrically piercing all around.

A further feature of the invention is that the longitudinal axis of the peripheral nozzle shoots at an angle 15 ^* perpendicular to the longitudinal axis of the mixer after the air flow device, and furthermore the longitudinal axis of the peripheral nozzle with the straight line perpendicular to the longitudinal axis of the mixer and passing through the peripheral nozzle emitter Decided angles up to 13 ^* to 17 ^* after gas flow setup.

The mixing chamber inlet (eg with the connection fitting) is connected to the mixer outlet when the mixing chamber is stands from the passage sector and from the supply sector. The supply sector is least comprised of a partial supply wall and at the same time it is approximately perpendicular to the horizontal plane of the supply sector and also to the direction of entry of the heating mixture. At least the first one made of supply part walls is produced as a screen, if it can also have its flat figure with a total air tube surface of about 28%. The supply line wall is the least coincident in height from the front wall of the mixing chamber with the heating mixture inlet and / or from the adjacent supply wall and / or from the section wall by horizontal length. The number of supply walls in the mixing chamber is defined as the width / length of the surface gas burner ratio. Only one partial wall of the supply line, when this ratio is greater than 0.4, becomes quite sufficient; meanwhile the ratio is up to 0.4 to 0.17, the two additional walls will be sufficient.

The following advantage according to this invention can be expected if the plane of the compartment wall and the horizontal plane of the feed chamber form an angle 80 ^* or the smallest. The penetration sector is made as an elongated prism with the vertical cross section of irregular polygons and the bottom of this penetration sector is formed by the surface burner, which also forms part of the upper surface of the combustion chamber.

The heat exchanger is made as a two-stage and forms it minimally a finned tube lying in the slack line, with the first end in the bottom of the combustion chamber and the second end of the finned tube in the base of the ascending channel with the siphon and the cascade of profiled fins. The descending duct is created with a system of profiling ribs between at least one of the ascending duct and at least one outer peripheral wall of the combustion chamber. The mouth of the descending end channel is linked to the axial feed line of the mixer (directly or indirectly - for example by mediating the connecting channel with a fan and ending with the connecting fitting). Within the main advantages of the condensation gas boiler, according to the invention, there is above all improved operational safety, which is achieved by using the prescribed mixer with the peripheral chamber for heating mixture design, because this avoids the structural mixture formation in the interior of the unit cabinet, for example when the combustion system is switched off when the combustion system is switched off automatically Mastery of aggregates, especially combined with gas monitoring. After the gas shut-off valve has been pushed in the gas supply line, the entire gas residue from the interior of the boiler is sucked out through spontaneously ended diffusion. Entire cabinet interior is best airtight and gas or heating mixture escaping through any leaks in the facility are back-venting back into the descending channel, from where they continued with fresh air in the mixer. Residual gas sealing also makes the cupboard heat escape lower, but this heat energy is intended for pre-heating the combustion air.

The mixing chamber solution allows substantial lowering of its height, which lowers demands on additional space and unburned heating mixture requirements.

Two-stage heat exchanger according to this invention at a heat turn of 70/50 ^* C makes maximum combustion product heat 55 ^* C possible. The water vapors condensed in the case of proper combustion product cooling, the acquisition of the relatively favorable condensate acid value and its discharge in the public sewer system without prior preparations (eg without neutralization).

Example of the implementation of the invention and description of illustrations

Several embodiments of the invention are shown in the drawing and are explained in more detail below. 1 shows a condensation gas boiler diagram in a horizontal cross section without control, regulation and indication parts; 2 shows the mixer with the circumferential chamber in elevation with a horizontal section; Fig. 3 shows a transverse section through the mixer of Fig. 2; 4 vertical cross section through the lower combustion chamber part with the heat exchanger FIG. 5 vertical cross section through the mixing chamber with the surface gas burner, and which have used the following reference numerals:

1 mixer 13 pipe

2 connection fitting 14 finned tube 3 circumferential chamber 15 ascent channel

4 Gas supply line 16 Profiling rib

5 circumferential nozzle 17 descending channel

6 Mixing chamber 18 Profiling rib

7 Supply sector 19 siphon 8 fitting 20 gas shut-off valve

9 fitting 21 fan

10 supply line wall 22 connecting channel

11 surface gas burner 23 cabinet

12 combustion chamber 100 department wall

The mixer JL is produced as a Venturi tube and is provided with an axial combustion air supply line with the connection fitting 2_. After the outer surface of the mixer 1_, the inner chamber is provided ^with its inner surfaces as profiling bodies of revolution and with a radial gas supply line. In the vicinity of the critical mixer inner diameter are three circumferential nozzles which penetrate symmetrically and all around, the length axes of which, with the flat axis of the mixer 1_ perpendicular to the length axis of the mixer, make an angle of 15 ^* according to the air flow direction. Angle 15 ^* after the gas flow device is also between the longitudinal axes of all circumferential nozzles 5_ and between straight lines perpendicular to the longitudinal axes and passing through the circumferential nozzle centers. The mixer outlet through the fitting 9_ arranged for the entry of the mixing chamber 6_. The mixing chamber 6_ consists of the passage sector 1_ and the feed sector jB, which are separating with the department wall 100. Resolve the department wall 100 and horizontal centric plane of the supply sector angle 80 ^* and the department wall 100 as a sieve with a total air tube area generated 28%. In the Supply sector 7. Are also two partial supply walls ^ 0 containing, perpendicular to the horizontal plane of the supply sector T_ and leading to the inlet device of the heating mixture. The first partial feed wall _6 is remote from the adjacent partial feed wall 10 and from the end forest of the mixing chamber 6_ with the heating mixture inlet, and the second partial feed wall 1__ from the partial compartment wall 100 by the same horizontal length, which is its height. The flat gas burner jLl. forms the bottom of the penetration sector J3 and a surface part of the combustion chamber part Y2__. The combustion chamber 12 is basically tapered and narrowed and four rows of heated tubes 1_3 are included. In the divided combustion chamber base there is a row of slanting finned tubes 1_, if each of them is in the combustion chamber space with the first end and with the second end in the descending channel L5 with the siphon 1 ^ 9 and the inner cascade of profiled ribs ljϊ is out. Between the outer circumferential wall of the ascending duct L5 and the outer circumferential wall of the combustion chamber L2, the descending duct L7 is created with a system of parallel profiling ribs ____. The opening of the descending duct ± 1_ to the axial feed line of the mixer 1_ is linked by means of the connecting duct ^ 2 to the electric fan 21_ and to the connecting fitting. The upper mouth of the ascending channel _15 is closed for the discharge of combustion products. Gas is fed into the space of the containment chamber 3_ into the outlet tube with the gas shut-off valve 2Q_; Combustion air for heating mixture formation with the fan 21 is operating. Atmospheric air is exhausting through the inlet opening in cabinet 23, of which it enters descending channel 1 ^ 7. Here, this air is preheated and continues around heat exchange surfaces of finned tubes 1 and through the connecting duct 22 to the fan 21. The air travels through the mixer 1, where it mixes with gas, diffusing through peripheral nozzles 5 _^ mediation with a screw-shaped barrel in the vicinity of the mixer interior surfaces. Resulting heating mixture is in the fitting j? leading up to the mixing chamber jS. Here, in the supply sector and in the supply wall passage, complete homogenization of the heating mixture and its uniform distribution over the entire gas burner area has ended. After passage of the gas burner nozzle, the heating mixture ignites and burns, continuing through the combustion chamber 12 leading to pipes J ^ 3 with heated media. The main condensation zone in the combustion chamber is dependent on the media temperature, which is fed back through the return circuit in tubes 3. Usually it lies at the level of the first or second row of the combustion chamber floor. From the combustion chamber L2, partially cool the combustion products around the row of finned tubes, where the beginning condensation continues and a portion of the heat of the combustion product transits into the finned tube surface. Condensation and the proportion of combustion product heat in the unit space according to the invention are terminated at profiling ribs 16 - of ^the descending end channel (15). Condensate flows back into siphon L9 and gas combustion products continue to lead outside, e.g. B. in chimney. Discharge heat gas combustion products with heat 70/50 ^* C most 55 ^* C does. Arrows in FIG. 1 show the flow directions in the condensing gas boiler according to the invention for clarity. The inner height of the mixing chamber J5 in leveling with other condensing gas boilers is 30% less. Mixer use for gas extraction and subsequent production of heating mixes in condensation gas boilers according to the invention makes reliable, uninterrupted operation possible even in conditions when this device for gas screen distribution with working pressure is imminent with a minimum usable value.

Claims

P A T E N T A N S P R Ü C H E 1. Mixing and heat exchange system of the condensation gas boiler, consisting of the supplying and connecting fittings, of minimally a combustion chamber exchanger with a surface gas burner and mixing chamber components, agree procured, and from ei¬ nen ^", appended to the lower combustion chamber part Wärmeaus¬ to Verbrennungspoduktenabkühlung and Simultaneous flow heating of the combustion air, characterized in that the mixer (1) is arranged between the gas and combustion air supply lines and the inlet of the mixing chamber (6), which is manufactured as a Venturi tube and with an axial combustion supply line, if necessary after the On the outside surface of the mixer (1), the circumferential chamber (3) with its inner surfaces is profiled as a hollow rotating body and provides radial gas feed line (4), meanwhile in the vicinity of the critical mixer inner diameter there are at least three circumferential and symmetrically piercing circumferences sen (5), if the mixing chamber (6) consists of the passage sector (8) and of the feeder sector (7), including least with a feeder part wall (10), donating approximately perpendicular to the horizontal plane of the feeder sector (7 ) and to the entry device of the heating mixture if the passage sector (8) has the vertical cross section of irregular polygons and the bottom of this passage sector (8) is formed by the surface gas burner (11) and simultaneously the supply sector (7) and the passage sector (8) are on both sides with the Department wall (100) separating, and / or the heat exchanger is made as a two-stage and forms it minimally a finned tube (14) lying in an oblique line with the first end in the bottom of the combustion chamber (12) and the second end of the bed Finned tube (14) in the base of the ascending channel (15) with the siphon (19) and with a cascade of profiling ribs (16) if between min The descending channel (17) is created with a system of profiled ribs (18) in an outer circumferential wall of the ascending channel (15) and at least one outer circumferential wall of the combustion chamber (12), and when the opening of the descending end channel (17) is for the axial feed of the mixer (1 ) linked, e.g. B. by means of tion of the connecting channel (22) with a fan (21) and / or with the connecting fitting (2) when the top of the ascending channel (15) is included for the discharge of combustion products. 2. Mixing and heat exchange system of the condensing gas boiler according to claim 1, characterized in that the longitudinal axis of the peripheral nozzle (5) with the longitudinal axis of the mixer (1) perpendicular flat land closes the angle 15 ^* according to the air flow direction. 3. Mixing and heat exchange system of the condensing gas boiler according to claim 1 or 2, characterized in that the longitudinal axis of the peripheral nozzle (5) with the line perpendicular to the longitudinal axis of the mixer (1) and through the peripheral nozzle center line up to 13 ^* resolved to 17 ^* after the gas flow facility. 4. Mixing and heat exchange system of the condensing gas boiler according to at least one of claims up to 3, dadurchge ¬ indicates that level of the department wall (100) and horizontal centric plane of the .supply sector (7) decides an angle 80 ^* or small. 5. mixing and heat exchange system of the condensing gas boiler according to at least one of claims up to 4, dadurchge ¬ indicates that minimally a supply line wall (10) and / or the partition wall (100) is produced as a screen and is from the end wall of the mixing chamber (6 ) with the entry of the heating mixture and / or from the neighboring supply part wall (10) and / or from the department wall (100) least horizontally by their length. 6. Mixing and heat exchange system of the condensation gas boiler according to at least one of claims up to 5, dadurchge ¬ indicates that the number of supply walls is a width / length of the surface gas burner ratio defined and this ratio is greater than 0.4 a partial supply wall (10) determines. meanwhile ratio up to 0.17 to 0.4 diesel number as two poor supply walls. 8. Mixing and heat exchange system of the condensing gas boiler according to at least one of claims up to 7, so that after heating mixture passage the first partial supply wall (10) is approximately 28% according to the flat figure with a total air tube.