Device for recycling steam condensate water of industrial boiler

Abstract

The utility model relates to the technical field of steam condensate recycling in the operation process of an industrial boiler, in particular to a device for recycling steam condensate of the industrial boiler, which comprises a water return tank connected with the input end of the boiler through a first pump body. A steam branch leading to the paper dryer heat exchange sleeve is arranged on the steam main pipeline at the output end of the boiler, the output end of the paper dryer heat exchange sleeve is connected with the steam-water separator, and the steam output end of the steam-water separator is connected with the steam main pipeline through a steam return pipe. And the condensate water output end of the steam-water separator is connected with the water return tank through a water return pipe. The device contributes to simultaneous recycling of heat energy in steam condensate and clean water, and the purposes of saving energy and reducing consumption are achieved.

Description

Technical Field

[0001] This utility model relates to the technical field of steam condensate recovery and utilization during the operation of industrial boilers, and particularly to a device for recovering and utilizing steam condensate from industrial boilers. Background Technology

[0002] When superheated steam generated by industrial boilers undergoes indirect heat exchange (such as in the paper industry where steam is used in a coaxial system for non-contact heat exchange with a paper dryer), the steam quality is unaffected by the heated substance, and its quality remains consistently ideal. Due to the physical isolation design of the heat transfer process, the steam neither comes into direct contact with the heated substance nor carries complex components from the production medium, such as pulp fibers and chemical additives, during the process. The resulting steam condensate essentially constitutes a clean water resource with a certain thermal value (typically maintaining a residual temperature of 80-120℃). The water quality indicators of this type of clean condensate are close to softened water standards, and its direct use as boiler feedwater can effectively reduce the ion exchange load of the water treatment system.

[0003] Currently, my country's "Energy Efficiency Limits and Energy Efficiency Grades for Industrial Boilers" standard lists this type of closed-loop condensate recovery technology as a key recommended direction for energy-saving renovations. If this portion of steam and condensate is recovered and reused simultaneously, the dual goals of saving boiler feedwater and fuel can be achieved. Utility Model Content

[0004] The purpose of this invention is to provide a device for recovering and utilizing steam condensate from industrial boilers. This device helps to simultaneously recover and utilize the heat energy and clean water in the steam condensate, thereby achieving the goal of energy conservation and consumption reduction.

[0005] The technical solution of this utility model is as follows: a device for recycling steam condensate from an industrial boiler, comprising a return water tank connected to the boiler input end via a first pump body, a steam branch line leading to the heat exchange sleeve of a paper dryer on the main steam pipeline at the boiler output end, the output end of the heat exchange sleeve of the paper dryer being connected to a steam-water separator, the steam output end of the steam-water separator being connected to the main steam pipeline via a steam return pipe, and the condensate output end of the steam-water separator being connected to the return water tank via a return water pipe.

[0006] Furthermore, a temperature sensor is installed on the return water tank.

[0007] Furthermore, a pressure regulating valve and a pressure gauge are installed on the steam branch.

[0008] Furthermore, the steam-water separator includes a primary steam-water separator and a secondary steam-water separator distributed vertically. The primary steam-water separator is equipped with a first steam trap connected to the output end of the heat exchange sleeve of the paper dryer. The steam output end of the first steam trap is connected to the steam return pipe. The bottom outlet of the primary steam-water separator is connected to the secondary steam-water separator.

[0009] Furthermore, the secondary steam-water separator is equipped with a second steam trap connected to the condensate output end of the primary steam-water separator. The steam output end of the second steam trap is connected to the steam return pipe, and the bottom outlet of the secondary steam-water separator is connected to the return water pipe.

[0010] Furthermore, a check valve, a solenoid valve, and a second pump body are sequentially arranged along the conveying direction on the return water pipe, and a level gauge electrically connected to the solenoid valve and the second pump body is installed inside the secondary steam-water separator.

[0011] Furthermore, both the first pump body and the second pump body are water pumps.

[0012] Furthermore, the pipelines between the return water tank and the boiler, the main steam pipeline, the steam branch pipeline, the pipeline between the paper dryer and the steam-water separator, the steam return pipe, and the return water pipe are all seamless steel pipes.

[0013] Furthermore, each of the seamless steel pipes is wrapped with insulation material on one side.

[0014] Furthermore, a pressure gauge or pressure sensor is installed on the main steam pipeline.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] This device achieves thorough separation of low-pressure steam and condensate through secondary steam-water separation, overcoming the pump cavitation problem common in conventional closed-loop steam condensate recovery devices. It features a simple structure, convenient maintenance and operation, and can achieve energy conservation and consumption reduction in industrial boilers. Furthermore, the steam in this device undergoes indirect heat exchange and is not contaminated by the heated substance; both steam and condensate can be directly reused, further reducing softened water treatment costs and lowering overall expenses. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model;

[0018] In the diagram: 1-Return water tank; 2-First pump body; 3-Boiler; 4-Main steam pipe; 5-Steam branch; 6-Paper dryer; 7-Steam-water separator; 71-First-stage steam-water separator; 711-First steam trap; 72-Second-stage steam-water separator; 721-Second steam trap; 722-Level gauge; 8-Steam return pipe; 9-Return water pipe; 10-Check valve; 11-Solenoid valve; 12-Second pump body; 13-Temperature sensor; 14-Pressure regulating valve; 15-Pressure gauge. Detailed Implementation

[0019] To make the above-mentioned features and advantages of this utility model more easily understood, specific embodiments are described below in conjunction with the accompanying drawings, but this utility model is not limited thereto.

[0020] refer to Figure 1

[0021] Taking steam condensate from a cardboard box factory as an example, the project adopts a closed-loop condensate recovery device. Through a closed-loop steam trap and pipelines, the steam condensate is collected into a closed water tank. Then, through a steam-water separator, the secondary steam and saturated condensate are separated, so that they maintain a certain space in the closed water tank and remain in a relatively stable state with the condensate. Finally, a water pump is used to output the condensate.

[0022] Specifically, an industrial boiler steam condensate recovery and utilization device includes a return water tank 1 connected to the input end of a boiler 3 via a first pump body 2. A main steam pipeline 4 is provided at the output end of the boiler. A steam branch 5 leading to the internal heat exchange sleeve of a paper dryer 6 is installed on the main steam pipeline. The output end of the heat exchange sleeve of the paper dryer is connected to a steam-water separator 7. The steam output end of the steam-water separator is connected to the main steam pipeline via a steam return pipe 8, and the condensate output end of the steam-water separator is connected to the return water tank via a return water pipe 9. Thus, the steam entering the steam-water separator after exiting the paper dryer is separated and sent back to the main steam pipeline for reuse, while the separated condensate is circulated back to the return water tank.

[0023] In this embodiment, to fully separate low-pressure steam and condensate, the steam-water separator includes a primary steam-water separator 71 and a secondary steam-water separator 72, arranged vertically. The primary steam-water separator is equipped with a first steam trap 711. The input end of the first steam trap is connected to the output end of the heat exchange sleeve of the paper dryer via a pipeline, and the steam output end of the first steam trap is connected to the steam return pipe via a pipeline, thereby returning the separated steam to the steam header for reuse. The bottom outlet of the primary steam-water separator is connected to the secondary steam-water separator so that the separated high-temperature steam condensate flows downwards to the secondary steam-water separator for further separation. Through secondary steam-water separation, condensate and steam can be further separated, thereby avoiding cavitation.

[0024] In this embodiment, a second steam trap 721 is installed inside the secondary steam-water separator. The input end of the second steam trap is connected to the condensate output end of the primary steam-water separator via a pipeline. The steam output end of the second steam trap is provided with a pipeline that passes through the primary steam-water separator and connects to the steam return pipe, so that the steam after secondary separation enters the main steam pipeline along with the steam separated from the primary steam-water separator. The bottom outlet of the secondary steam-water separator is connected to the return water pipe to reuse the separated condensate.

[0025] In this embodiment, a check valve 10, a solenoid valve 11, and a second pump body 12 are sequentially arranged along the conveying direction on the return water pipe. A level gauge 722, electrically connected to the solenoid valve and the second pump body via a controller, is installed inside the secondary steam-water separator. Thus, when the separated condensate reaches a certain level, the solenoid valve and the second pump body are opened, circulating the condensate back to the return water tank. Through secondary steam-water separation, the condensate and steam can be further separated, thereby preventing cavitation.

[0026] In this embodiment, both the first pump body and the second pump body are water pumps, specifically centrifugal pumps or other pump bodies.

[0027] In this embodiment, the pipelines between the return water tank and the boiler, the main steam pipeline, the steam branch pipeline, the pipeline between the paper dryer and the steam-water separator, the steam return pipe, the return water pipe, and the pipeline between the primary steam-water separator and the secondary steam-water separator are all seamless steel pipes, and each seamless steel pipe is wrapped with insulation material on one side. This effectively reduces heat loss of steam and condensate during the flow process.

[0028] In this embodiment, the boiler is an industrial boiler, and a pressure gauge or pressure sensor is installed on the main steam pipeline or the boiler outlet steam pipeline.

[0029] In this embodiment, a temperature sensor 13 is installed on the return water tank to monitor the water temperature in the return water tank.

[0030] In this embodiment, a pressure regulating valve 14 and a pressure gauge 15 are provided on the steam branch. The pressure of the superheated steam is adjusted to the required pressure, such as 0.3 MPa, by means of the pressure regulating valve.

[0031] Condensate from the return water tank enters the boiler via the first pump, while water from other feedwater tanks is also pumped into the boiler. Under the heating of the industrial boiler, the condensate and other feedwater form superheated steam at a pressure exceeding 0.5 MPa. A branch of the steam pipeline, after its pressure is adjusted to 0.3 MPa by a pressure regulating valve, enters the heat exchanger jacket of the paper dryer to exchange heat with the pulp. After heat exchange, the steam pressure decreases, forming a mixture of low-pressure steam and condensate that enters the steam-water separator.

[0032] The core components of the steam-water separator are the primary and secondary steam-water separators. The mixture of low-pressure steam and condensate first enters the primary separator. A first steam trap in the primary separator separates the low-pressure steam from the condensate. The separated low-pressure steam enters the main steam pipeline for reheating and pressurization, and is then reused. The separated condensate flows from top to bottom through the primary separator into the secondary separator. A second steam trap in the secondary separator further separates the condensate from the low-pressure steam. The low-pressure steam separated in the secondary separator enters the primary separator and then enters the main steam pipeline for heating and pressurization. The condensate separated in the secondary separator is temporarily stored in the tank. A level gauge in the secondary separator sends a signal to the controller when the level reaches a certain level. The controller then activates a solenoid valve and a water pump to send the condensate to the return tank. This secondary steam-water separation further separates the condensate from the steam, thus preventing cavitation.

[0033] If the terms "first" and "second" are used in the above-described utility model to define the components, those skilled in the art should know that the use of "first" and "second" is merely for the purpose of distinguishing the components in the description. Unless otherwise stated, the above terms have no special meaning.

[0034] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws) or a non-detachable fixed connection (e.g., riveting or welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0035] In addition, unless otherwise stated, the terms used in any of the technical solutions disclosed in this utility model to indicate positional relationships or shapes include states or shapes that are similar to, close to, or approximate with those states or shapes.

[0036] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0037] The above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall be covered by the present utility model.

Claims

1. An apparatus for recovering and utilizing steam condensate water of an industrial boiler, comprising a return water tank connected to an input end of the boiler via a first pump body, characterized in that, The steam main pipe of the boiler output end is provided with a steam branch pipe connected to the paper dryer heat exchange sleeve, the output end of the paper dryer heat exchange sleeve is connected to a steam-water separator, the steam output end of the steam-water separator is connected to the steam main pipe through a steam return pipe, and the condensed water output end of the steam-water separator is connected to a return water tank through a return water pipe.

2. The device for recovering and utilizing industrial boiler steam condensate water according to claim 1, characterized in that, The return water tank is provided with a temperature sensor.

3. The device for recovering and utilizing industrial boiler steam condensate water according to claim 1, characterized in that, The steam branch pipe is provided with a pressure regulating valve and a pressure gauge.

4. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 1, 2 or 3, characterized in that, The steam-water separator comprises a first steam-water separation tank and a second steam-water separation tank distributed vertically, the first steam-water separation tank is provided with a first drain valve connected to the output end of the paper dryer heat exchange sleeve, the steam output end of the first drain valve is connected to the steam return pipe, and the bottom outlet of the first steam-water separation tank is connected to the second steam-water separation tank.

5. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 4, characterized in that, The second steam-water separation tank is provided with a second drain valve connected to the condensed water output end of the first steam-water separation tank, the steam output end of the second drain valve is connected to the steam return pipe, and the bottom outlet of the second steam-water separation tank is connected to the return water pipe.

6. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 5, characterized in that, The return water pipe is sequentially provided with a check valve, an electromagnetic valve and a second pump body along the conveying direction, and the second steam-water separation tank is provided with a liquid level meter electrically connected to the electromagnetic valve and the second pump body.

7. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 6, characterized in that, The first pump body and the second pump body are water pumps.

8. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 1, 2, 3, 5, 6 or 7, characterized in that, The pipelines between the return water tank and the boiler, the steam main pipe, the steam branch pipe, the pipelines between the paper dryer and the steam-water separator, the steam return pipe and the return water pipe are all seamless steel pipes.

9. An apparatus for recovering and utilizing steam condensate water of an industrial boiler according to claim 8, characterized in that, The seamless steel pipes are all wrapped with heat insulation materials on the outside.

10. The device for recovering and utilizing steam condensate water of an industrial boiler according to claim 1, characterized in that, The steam main pipe is provided with a pressure gauge or a pressure sensor.

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