CZ27648U1 - Device to control injection systems with two-medium nozzle - Google Patents

Description

Technical field

The technical solution relates to an injection system for two-medium nozzles, eg for supplying compressed air and a reducing mixture, eg a liquid mixture of a reducing agent with dilution water, to the combustion chambers of furnaces and boilers firing solid, gaseous and liquid fuels and waste. means for example aqueous solution of technical urea or ammonia water etc.

In particular, the present invention relates to a device for controlling injection systems with a two-medium nozzle to ensure safe and economical operation of such systems. The two-medium nozzle is used, for example, in injection systems / injection lances for injection into the combustion chambers of furnaces and boilers firing solid, gaseous or liquid fuels and possibly waste.

BACKGROUND OF THE INVENTION

Injection systems of particularly large combustion plants often consist of multiple injection lances equipped with a two-medium nozzle. For process-related reasons, it may be required to shut down some of the injection lances. This requirement arises especially when used in SNCR (selective non-catalytic NO _X reduction) technology. The shutdown is effected, for example, by closing the flow of the reducing agent and by limiting the flow of the carrier medium (air) by means of an el. operated valves. This procedure is very costly and, due to the large number of switching operations, can also affect the availability of the entire device. If the amount of carrier medium were not reduced, the consumption of this carrier medium would be very high and the injection operation would be uneconomical.

The aim of this technical solution is therefore to design a device as simple as possible, which allows to shut down individual spears ideally without the need for el. energy, and allow low air consumption of the entire injection system.

The essence of the technical solution

This object is achieved with the aid of a two-nozzle injection system control system comprising a body with a reducing agent inlet and outlet or a mixture of a reducing agent with dilution water and an air inlet and outlet, and a piston with openings for permitting maximum air flow in the open state and with respect to the orifices offset by the arranged smaller orifices for the reduction of the reduced amount of air in the closed state, so that air from the inlet to the outlet flows in the open state through the orifices for the maximum amount of air and slidable from the closed state to the open state when the pressure of the reducing agent or the mixture of reducing agent with dilution water exceeds a certain threshold, and the device further comprises a means for automatically returning the piston to a closed state when the pressure of the reducing agent or reducing agent / diluent mixture drops below a certain threshold.

The body and / or the piston is preferably provided with at least one sealing element for separating the individual working medium spaces. The means for automatically returning the piston is preferably a spring by biasing the piston to the closed state until the pressure of the reducing agent or the mixture of reducing agent with dilution water rises above a certain threshold. Preferably, the overall cross section of the outlet opening (s) is smaller than the overall cross section of the inlet opening (s). Preferably, the piston in the closed state of the device closes the passage of the reducing agent or reducing agent mixture with the dilution water between the inlet and the outlet.

-1 CZ 27648 Ul

Such a device may advantageously be part of two-nozzle or lance injection systems, in particular for supplying pressurized air and reducing agent mixture with dilution water to the combustion chambers of furnaces and boilers firing solid, gaseous and liquid fuels.

This device has a very simple construction, does not contain any electrical components and therefore has low production costs and, in particular, is very reliable and has a long service life.

Further advantages of this device are the reduction in the consumption of compressed air atomization used to cool the injection systems when the injection systems (single lances) are shut down, as well as the energy savings necessary to adjust the electro-pneumatic or electromagnetic fittings in existing injection systems.

From the point of view of operational reliability and long life, it is further advantageous according to the invention that all steel parts are made of stainless steel and the sealing elements are made of a material resistant to operating fluids.

An advantageous feature of the present invention is also that such a device can be implemented directly into the injection system or directly into the injection lances.

Clarification of drawings

Further advantages and features of the present invention are further evident from the drawings, in which:

Fig. 1 shows a longitudinal section of one embodiment of the device according to the invention, including all its constituent parts in a closed state; Fig. 2 shows the same device in the same views in the open state; Fig. 3 shows, in the same views, another embodiment example; Fig. 4 shows the device of Fig. 3 in an open state.

Examples of technical solutions

The device for controlling two-die nozzle injection systems, also referred to herein as a device for the safe and economical operation of two-die nozzle injection systems, in the illustrated embodiments of the present invention consists essentially of:

- bodies I with inlet and outlet ports for reducing agent or reducing agent mixture with dilution water (inlet 11 and outlet 12) and for pressurized spray air (inlet 13 and outlet 14),

- a piston 2 for switching operating states, namely the initial closed state 10, 10 '. 1 and 2, respectively. 3, and an open state of 20. 20 '. 2 and 2, respectively. 4,

- a spring 3 for moving the piston to the starting position, where a reduced amount of atomizing air flows through the device for the safe and economical operation of the two-nozzle injection systems,

sealing elements 4 for separating the individual working medium spaces, and

- optionally closing elements 5 for closing the device.

The cylindrical part of the body 1 is provided with inlet orifices which can be arranged optionally with the same or different cross-sections and / or with a different configuration of their media connection openings, eg threaded, welded or flanged, and thus adaptable to the inlets and outlets of different injection system bodies and / or injection lances.

The body 1 may also be directly part of an injection system, for example injection lances.

The ends of the body 1 are in these exemplary embodiments provided with threads for closing and a secure sealing with the closing elements 5. The device is furthermore preferably provided, for example, with a screw 9 forming a stop for the extreme positions of the piston 2 corresponding to the closed state. open device state.

-2EN 27648 Ul

In the housing I, openings are preferably made in the media inlets so that they are on the inlet side IJ. of the reducing agent or mixture, the opening was larger than on the outlet side 12 of the reducing agent or mixture to provide the necessary opening pressure. The inlet and outlet openings on the spray air inlet and outlet 13, 14 may be of the same or different diameters. Of course, the spray air inlet 13 and the spray air outlet 14 may also be arranged opposite each other. Grooves may be formed in the body 1 and / or the piston 2 for accommodating the sealing elements 4.

The piston 2 is provided with openings 15, 16 for the passage of compressed air in the open state of the device (FIGS. 2, 4). These openings 15, 16 have a diameter such as to ensure sufficient atomization and sufficient pressure and flow of atomizing air.

Preferably, the piston 2 is further provided with smaller holes 17, 18 for the passage of a smaller amount of atomizing air designed to ensure sufficient cooling of the injection system, such as injection lances and nozzles, even in the initial position, i.e. the closed state of the device. , 3).

The spring 3 is designed to automatically secure the piston 2 to its initial position upon loss of pressure of the reducing agent or reducing agent mixture with dilution water at the inlet of the device for the safe and economical operation of the two-medium nozzle injection systems. The spring is preferably formed as a compression coil spring of stainless steel.

The sealing elements 4 are designed to safely separate the working space of the reducing agent or the mixture of reducing agent with dilution water from the working space of the atomizing air. Furthermore, it is also possible to separate the individual atomizing air chambers by means of the sealing elements 4 so that the atomizing air cannot penetrate into the adjacent chambers and thereby increase the consumption of the cooling atomizing air.

The closure elements 5, for example plugs or caps for closing the device body for safe and economical operation of two-nozzle injection systems, can also be used as media inlets (this alternative embodiment is not shown, in the illustrated embodiments all the necks are formed directly in cylindrical body part I).

Due to the properties of the working medium, which is typically an aqueous solution of technical urea or ammonia water and the like, the body I, the piston 2, the spring 3 and the accessories (e.g. closing elements

5) Made of stainless steel to prevent the corrosive effect of the reagent.

In the initial, so-called closed state (shown in Figures 1 and 3), the inlet 13 and the outlet 14 of the compressed air are not connected through the openings 15, 16, but only through the smaller openings 17,18, so that only a reduced amount of air can flow through the device. . In the first exemplary embodiment of the device shown in FIG. 1, the reducing means, respectively, can be operated via the device for the safe and economical operation of the two-nozzle injection systems. the mixture flows freely from the inlet 11 to the outlet 12. In the second embodiment shown in FIG. 3, the device not only closes the compressed air openings 15, 16 by means of its piston 2, but also separates the inlet 11 and the outlet 12 for the reducing agent. In this second exemplary embodiment, shown in FIG. 3, by means of a device for the safe and economical operation of injection systems with a two-medium nozzle, the reducing means or the mixture of the two in the nozzle 2 are closed. the mixture cannot pass.

This device for the safe and economical operation of the two-nozzle injection systems works by automatically raising the pressure reducing agent / diluent / diluent water mixture to a certain threshold from a closed state to an open state, the pressure reducing fluid of the reducing agent / reducing agent / water mixture moves the piston 2 from the position shown in FIGS. 1, 3 to the position shown in FIGS. 2, 4 (i.e., to the right) while compressing the spring 3. In the second exemplary embodiment (FIGS. 3 and 4), the fluid from the inlet H directly acts on the piston 2 since it cannot escape anywhere. In the first exemplary embodiment (Figs. 1 and 2), where the liquid can also exit the outlet 12 even when the device is closed, to adjust the piston on the basis of

Advantageously, the cross section of the fluid outlet opening (or holes) 12 is smaller than the cross section of the inlet opening Π. liquid.

By adjusting the piston 2, the inlet 13 and the outlet 14 of the air part of the device are connected so that the maximum air flow is allowed. In this open state (i.e. in the operating position of the device) shown in Figures 2 and 4, the maximum amount of compressed air flows through the device, namely from the inlet 13 through the opening 15 to the piston 2, through the piston 2, and through the opening 16 This compressed air can thus be used to spray the reducing agent or the reducing agent mixture with the diluent water in the injection systems of the combustion chambers of furnaces and boilers firing solid, gaseous and liquid fuels and wastes.

In the first embodiment (Figs. 1 and 2), the displacement of the piston 2 does not affect the passage of the reducing agent or the mixture of the reducing agent with the dilution water; in the second embodiment (Figs. 3 and 4) the passage of the reducing agent or the in the closed state, the device is closed, in this example embodiment by releasing the outlet 12.

If the pressure of the reducing agent liquid or the reducing agent mixture with the dilution water at the inlet 11 of the device for safe and economical operation of two-nozzle injection systems is dropped (below a certain threshold), the spring 3 automatically releases the piston 2 to its initial position; the device thus switches from the open state (Figs. 2, 4) back to the closed state (Figs. 1, 3), with only a reduced amount of air flowing through the air portion through the smaller holes 17, Γ8 in the piston 2; 3 and 4) the passage of the reducing agent or mixture is additionally closed.

A method for controlling two-nozzle injection systems with such a device, in particular for supplying compressed air and a reducing agent mixture with dilution water to the combustion chambers of furnaces and boilers firing solid, gaseous and liquid fuels, is characterized in that of the reducing agent with dilution water above a certain threshold, the maximum amount of air is released, and when the pressure of the reducing agent or the mixture of reducing agent with dilution water falls below a certain threshold, only the reduced amount of air is released. Preferably, when the pressure of the reducing agent or the reducing agent mixture with the diluent water exceeds a certain threshold, the passage of the reducing agent or the reducing agent mixture with the diluent water between the inlet U and the outlet 12 opens, and with water below a certain threshold, the passage of the reducing agent or reducing agent / diluent mixture between the inlet 11 and the outlet 12 is closed.

The openings 15 and 16 and the openings 17 and 18 may also coincide in another exemplary embodiment, and may consist, for example, of one channel formed in the material of the piston 2 (not shown in the figure) instead of separate openings in the hollow piston body. In such an embodiment, the air then flows from the inlet 13 to the outlet 14 in the closed state through thus forming a channel for reduced air volume, and in the open state through the thus formed channel for maximum air volume.

Equipment for the safe and economical operation of two-die nozzle injection systems can be installed without any restriction on existing injection systems and / or injection lance without affecting existing technological elements of SNCR technology. Furthermore, the device can be used as a separate component for the safe and economical operation of two-die nozzle injection systems or directly implemented in the injection molding body.

Claims (7)

PROTECTION REQUIREMENTS An apparatus for controlling injection systems with a two-medium nozzle, characterized in that it comprises: body (1) with inlet (11) and outlet (12) of the reducing agent or reducing agent mixture with dilution water and with inlet (13) and air outlet (14), and a piston (2) with orifices (15, 16) for leakage the maximum amount of air in the open state (20, 20 ') of the device and with respect to the openings (15, 16) offset by the arranged smaller openings (17, 18) for passing the reduced amount of air in the closed state (10, 10') of the device, from the inlet (13) to the outlet (14) flows in the open state (20, 20 ') through the apertures (15, 16) for permitting the maximum amount of air and in the closed state (10, 10') through the apertures (17, 18) releasing a reduced amount of air, wherein the piston (2) is slidably mounted in the body (1) from the closed state (10, 10 ') to the open state (20, 20') as the reducing agent or reducing agent / diluent mixture exceeds a certain prahovo and the device further comprises means for automatically returning the piston (2) to the closed state (10, 10 ') when the pressure of the reducing agent or the mixture of reducing agent and dilution water falls below a certain threshold. Device according to the preceding claim, characterized in that the body (1) and / or the piston (2) is fitted (o) with at least one sealing element (4) for separating the individual working medium spaces. Device according to any one of the preceding claims, characterized in that the means for automatically returning the piston (2) is a spring (3) by biasing the piston (2) into the closed state (10, 10 ') until the pressure of the reducing agent or mixture the reducing agent with the dilution water does not rise above a certain threshold. Device according to any one of the preceding claims, characterized in that the total cross-section of the opening (s) of the outlet (12) is smaller than the total cross-section of the opening (s) of the inlet (11). Device according to any one of the preceding claims, characterized in that, in the closed state (10 ') of the device, the piston (2) is in a position relative to the other components of the device that closes the passage of the reducing agent or reducing agent mixture with the diluent. input (11) and output (12). Device according to any one of the preceding claims, characterized in that all steel parts are made of stainless steel and the sealing elements are made of a material resistant to working fluids. Injection system with a two-medium nozzle or injection lance, in particular for supplying compressed air and a mixture of reducing agent with dilution water to the combustion chambers of furnaces and boilers firing solid, gaseous and liquid fuels, characterized in that it comprises a device according to any one of the preceding claims.