RU2670999C2 - Multipass horizontal network heater - Google Patents

Abstract

FIELD: heat-and-power engineering.

SUBSTANCE: invention relates to heat power engineering, to network heaters of horizontal type. Object of the invention is to develop a more compact system for heating the network water. It is achieved by combining two heating stages in one network heater by increasing the diameter of the pipe system while maintaining the length of the pipes. Multipass horizontal network heater has steam supply by several steam pipes along the housing. Internal vapor space of the body is divided by a longitudinal partition into two parts and one part of the steam is fed from the extraction of a smaller pressure, and into the other part from the extraction of a higher pressure.

EFFECT: such a heater has several advantages: a more compact arrangement of the same heat exchange surface in one heater instead of two and, correspondingly, a reduction in the cell in the computer room; the length of the steam supply pipelines decreases, and accordingly the pressure loss and underheating; decreases the radiation of heat into the engine room.

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Description

The invention relates to a power system, to network heaters of a horizontal type. In cogeneration turbines, two-stage heating of network water is used to increase efficiency. Traditionally, two network heaters are installed at the same time, connected in series to the selection of the first heating stage (low pressure 0.04-0.2 MPa) and to the selection of the second heating stage (high pressure 0.06-0.3 MPa), respectively. The samples are located at a small distance (0.5-0.8 m) before and after the intermediate compartment with a small pressure difference (0.05-0.25 MPa). The heaters have a length of 6-10 m and a diameter of 2-3.5 m. Therefore, there is the problem of compact placement of two heaters in the engine room. The sampling pipelines have a diameter of about 1 m, and are connected in two to four places located along the heater. An increase in their length leads to additional pressure losses. In addition, to replace the heater pipes in the engine room, it is necessary to provide 6-10 m free space.

Known designs of combined high-pressure heaters (Efimochkin GI Two-lift deaerator-free steam turbine scheme of thermal power plants and thermal power plants. Heat power engineering. 1997. No. 1. P. 20-24), in which the input chamber is combined and the total length is not significantly reduced.

For the prototype, we take the specified combined heater, as well as two serial heaters with two-stage heating of the mains water. The aim of this invention is to develop a more compact system for heating network water. It is achieved by combining two stages of heating in one network heater by increasing the diameter of the pipe system while maintaining the length of the pipes. Indeed, the same volume and heating surface can be obtained by increasing the diameter of the casing by about 1.4 times. This is possible for medium heaters with a case diameter of up to 2.6 m (for example, PSG-800, PSG-1250, PSG-1300, PSG-3000), that is, for almost all heaters except for powerful heaters PSG-4900, PSG-5000 .

In FIG. 1 shows a cross section of the proposed two-stage horizontal network heater. The body of the steam space 9 is divided into two parts by cylindrical longitudinal partitions 10. The pipe system consists of four strokes 1, 2, 3, 4 (shaded in Fig. 1), through the tubes of which water passes sequentially, which is brought into the inlet chamber by the pipe 16 to the first stroke and is discharged by the pipe 17 after the fourth stroke. The steam of the first heating stage from the selection of lower pressure is supplied by two or four nozzles 12 located in the upper right part along the body, and its condensate is discharged by the nozzle 13 into its condensate collector. The steam of the second heating stage from the selection of greater pressure is supplied by two or four nozzles 14 located in the upper left part along the body, and its condensate is discharged by the nozzle 15 into its condensate collector. The location of several steam supply nozzles along the housing leads to a predominantly transverse flow around the pipes, which improves heat transfer.

The location of the partitions of the rotary and inlet chambers, as implemented in existing structures, provides for the sequential passage and heating of water in passages 1-4. In particular, after the second stroke in the inlet chamber, water enters the third stroke.

The pressure in the vapor space is small 0.05-0.3 MPa, but due to the large diameter of the body (up to 3.6 m), the stresses in the partitions 10 are increased. It is possible to install a flat partition, but several couplers (rigid joints) are required and with the body. One cylindrical partition of a large diameter without screeds is also possible, but even in this case the stresses will be increased and its thickening will be required. A combined partition is recommended, consisting of two cylindrical partitions with reduced radii, connected to the casing with one screed 11, which will require a smaller partition thickness than the casing thickness. A combination of flat and cylindrical partitions is also possible.

The proposed horizontal network heater is much more compact than two heaters, as it has a case diameter increased by 1.4 times. The layout of the machine room is simplified, since the placement of one heater is much simpler than two of the same length. One free space required to replace pipes. Steam supply pipelines will have a shorter length, respectively, pressure loss and underheating are reduced. The area of the heater, radiating heat, is reduced by 1.4 times, which improves the temperature regime of the engine room. It is advisable to replace two heaters with a surface of 1300-3000 m ² with one two-stage. Most existing four-way heaters. To maintain the available (optimal) speeds, it is necessary that each of the parts be four-way.

A feature of the proposed heater is that after the last stroke of the first heating step, it is necessary to ensure the flow of water into the first stroke of the second heating step. In FIG. 2 shows such an option. The water supply to the first stage is performed by a pipe 16 in the upper part of the inlet chamber, and the transfer from the fourth to the fifth stroke is easy to carry out in the lower part, since these moves are nearby. In this case, steam can be supplied to the first heating stage in the lower part of the housing. To preserve the traditionally accepted heating of the beams, when the steam is supplied from the side of the last stroke of each heating stage, it is possible to propose the layout of the pipe system shown in FIG. 3., which provides enough space for the flow of water from the fourth to the fifth move. The partition separating the two stages of heating is located in the steam space, and the partitions separating the course of the partition are in the inlet and the rotary chambers.

A two-stage horizontal network heater has the following technical result:

- More compact placement of the same heat exchange surface in one heater instead of two and, accordingly, reduction of the cell in the engine room.

- Reduces the length of the steam supply pipelines and, accordingly, pressure loss and underheating.

- Reduces heat radiation in the engine room.

Claims (1)

A multi-way horizontal network heater with steam supply by several steam pipelines located along the body, characterized in that the internal steam space of the body is divided into two parts by a longitudinal partition and in one part of the steam is supplied from the selection of lower pressure, and in the other part from the selection of higher pressure.

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