Steam condensate water hammer prevention and waste heat utilization device

Abstract

The utility model discloses a steam condensate waterproof hammer and waste heat utilization device, its characterized in that, including steam condensate tank, first condensate feed heat exchanger and heat tracing station, set up low temperature steam condensate main, high temperature steam condensate main respectively gather low temperature steam condensate and high temperature steam condensate, low temperature steam condensate and high temperature steam condensate after heat exchange through first condensate feed heat exchanger respectively enter steam condensate tank, mixed condensate in steam condensate tank is transported to heat tracing station by condensate pump, and heat tracing station return water is connected to condensate external discharge pipeline, set up the differential pressure valve between heat tracing station import and export. The device transports high, low temperature condensate respectively to steam condensate tank heat exchange and neutralizes, avoids the water hammer of equipment, pipeline, and utilizes steam condensate to replace steam heat tracing, and effectively recycles waste heat, saves the steam use amount.

Description

Technical Field

[0001] This utility model belongs to the field of public works technology, specifically relating to a steam condensate waterproof hammer and waste heat utilization device. Background Technology

[0002] Public utilities are supporting infrastructure that provides basic energy supplies such as water, electricity, and gas to industrial production systems, as well as environmental protection facilities. They include subsystems such as water supply and drainage, gas supply, steam supply, power supply, heating, and refrigeration. Steam pipeline networks are prevalent in petrochemical and other industrial enterprises. For example, in the olefin separation unit of a methanol-to-olefins (MTO) plant, steam serves as the heat source for heating distillation columns, catalyst activation and regeneration, flare system heating, material recovery and vaporization heating, and instrument and process piping heat tracing. These heat exchange processes generate a large amount of steam condensate. Simultaneously, some condensate is also generated by the low-point steam traps in the steam pipelines. The collected steam condensate is then sent to the plant's steam condensate recovery system.

[0003] Due to the varying temperatures of the heat exchange medium, the temperatures of the generated steam condensate differ. When condensate from different branches converges, it can cause water hammer in the heat exchanger and condensate pipelines. This can lead to leaks in equipment flanges or, in severe cases, damage and rupture of pipelines and equipment, threatening the safe operation of the plant. Most instruments and equipment in olefin separation units requiring winter heating are related to C1-C4 hydrocarbons. Using steam above 100°C directly as heat tracing can easily cause hydrocarbon materials to vaporize, resulting in excessively high local temperatures in equipment or pipelines. This can lead to deformation or cracks, causing leaks. Furthermore, the high temperature can vaporize the material in the pressure taps of liquid-phase instruments, affecting the accuracy of instrument measurements. Additionally, the increased steam consumption due to winter freeze protection means that much of the steam's heat is not effectively recovered. Summary of the Invention

[0004] The purpose of this utility model is to provide a steam condensate water hammer prevention device and a waste heat recovery device, which can prevent equipment and pipelines from leaking or malfunctioning due to steam condensate water hammer; at the same time, it can effectively recover waste heat, save steam consumption of the device, and reduce the phenomenon of inaccurate instruments or equipment failure caused by steam heating.

[0005] To achieve the above-mentioned objectives, this utility model provides a steam condensate waterproof hammer and waste heat utilization device, characterized in that it includes a steam condensate tank, a first condensate feed heat exchanger, and a heat tracing station. A low-temperature steam condensate main pipe and a high-temperature steam condensate main pipe are provided to collect the low-temperature steam condensate and the high-temperature steam condensate, respectively. The low-temperature steam condensate and the high-temperature steam condensate exchange heat through the first condensate feed heat exchanger and then enter the steam condensate tank. The mixed condensate in the steam condensate tank is pumped to the heat tracing station by a condensate pump. The return water of the heat tracing station is connected to the condensate discharge pipeline. A differential pressure valve is installed between the inlet and outlet of the heat tracing station.

[0006] Furthermore, the heat tracing station is equipped with a condensate inlet valve at the inlet and a condensate return valve at the outlet.

[0007] Furthermore, the device also includes a steam condensate tank venting heat exchanger, wherein the low-temperature steam condensate exchanges heat with the vented steam discharged from the top of the steam condensate tank before entering the condensate feed heat exchanger.

[0008] Furthermore, the device also includes a second condensate feed heat exchanger, wherein the high-temperature steam condensate and the condensate discharged from the outlet of the heat tracing station are connected to the condensate discharge pipeline after exchanging heat through the second condensate feed heat exchanger.

[0009] Beneficial effects: This utility model's steam condensate water hammer prevention and waste heat utilization device separately transports high-temperature condensate and low-temperature condensate to the steam condensate tank via pipelines. Utilizing the temperature differences between the various condensates, heat exchange and neutralization are achieved, preventing water hammer in equipment and pipelines. The condensate enters the heat tracing station where steam condensate replaces steam tracing, saving steam consumption. It also reduces the occurrence of inaccurate instrumentation or equipment malfunctions caused by hydrocarbon vaporization during steam tracing. Specifically, it includes: 1) Avoid water hammer in steam heat exchangers and steam condensate pipelines to prevent leaks or accidents; 2) Reduce the occurrence of inaccurate instruments or equipment malfunctions caused by the vaporization of hydrocarbons due to steam heating; 3) Saves steam consumption of the equipment.

[0010] The device of this invention is highly practical and easy to operate. After being put into use, it can ensure the stability of the device, reduce the difficulty of process operation, maintenance costs and operating risks in the production process, and has significant economic benefits. Attached Figure Description

[0011] Figure 1 is a schematic diagram of the structure of the steam condensate waterproof hammer and waste heat utilization device of this utility model; Among them, 1. Steam condensate tank, 2. First condensate feed heat exchanger, 3. Second condensate feed heat exchanger, 4. Steam condensate tank venting heat exchanger, 5. Condensate pump, 6. Steam condensate tank venting line, 7. Low temperature steam condensate user pipeline, 8. Condensate external drainage line, 9. High temperature steam condensate user pipeline, 10. Differential pressure valve, 11. Condensate inlet valve of the heat tracing station, 12. Condensate return valve of the heat tracing station, and 13. Heat tracing station. Detailed Implementation

[0012] The technical solution of this utility model will be further described in detail below through specific embodiments. However, it should be noted that the following embodiments are only used to describe the content of the invention and do not constitute a limitation on the protection scope of this utility model.

[0013] like Figure 1A device for preventing water hammer and waste heat utilization of steam condensate includes a steam condensate tank 1, a first condensate feed heat exchanger 2, a second condensate feed heat exchanger 3, a steam condensate tank venting heat exchanger 4, a condensate pump 5, a steam condensate tank venting line 6, a low-temperature steam condensate user pipeline 7, a condensate external drainage line 8, a high-temperature steam condensate user pipeline 9, a differential pressure valve 10, a condensate inlet valve for a heat tracing station 11, a condensate return valve for a heat tracing station 12, and a heat tracing station 13.

[0014] According to the device of this utility model, the low-temperature steam condensate user pipelines 7 are collected into the low-temperature steam condensate main pipe. The low-temperature steam condensate is first sent to the steam condensate tank venting heat exchanger 4 to exchange heat with the venting steam at the top of the steam condensate tank 1 to recover residual heat. Then, after exchanging heat with the high-temperature steam condensate through the first condensate feed heat exchanger 2, the condensate enters the steam condensate tank 1.

[0015] Each high-temperature steam condensate user pipeline 9 converges into the high-temperature steam condensate main pipe. The high-temperature steam condensate enters the second condensate feed heat exchanger 3, where it exchanges heat with the discharged condensate to cool down. Then, it enters the first condensate feed heat exchanger 2 to exchange heat with the low-temperature steam condensate to cool down. Finally, the condensate enters the steam condensate tank 1.

[0016] After the two streams of condensate merge in the steam condensate tank 1, most of the condensate is transported to the heat tracing station 13 by the condensate pump 5. The return water of the heat tracing station 13 is connected to the condensate drain line 8. A differential pressure valve 10 is installed between the inlet and outlet of the heat tracing station 13, and a small portion of the condensate enters the condensate drain line 8 after passing through the differential pressure valve 10. The differential pressure valve 10 at the outlet of the condensate pump 5 controls the pressure difference before and after the valve. The condensate before the differential pressure valve 10 flows to the heat tracing station 13 through the condensate inlet valve 11. The return water of the heat tracing station flows to the heat tracing station 13 through the condensate return valve 12, sending the condensate to the differential pressure valve 10. After passing through the second condensate feed heat exchanger 3, the condensate exchanges heat with the high-temperature steam condensate to raise its temperature, and then the condensate is discharged to the downstream system through the condensate drain line 8.

[0017] The heat tracing station 13 is used for winter protection heating of instruments and equipment in the olefin separation unit to prevent freezing, shutdown, or accidents.

[0018] In existing steam condensate recovery systems, the process is as follows: steam user condensate (including condensate from heating stations and steam low-point drain lines) → condensate main → steam condensate recovery system. When condensate from various sources converges, water hammer is likely to occur.

[0019] The device of this utility model is equipped with a low-temperature steam condensate line, a high-temperature steam condensate line, a steam condensate tank, a condensate pump, a condensate feed heat exchanger, and a condensate tank venting heat exchanger. The modified condensate recovery process is as follows: Low-temperature steam user → Low-temperature steam condensate line → Condensate tank venting heat exchanger → First condensate feed heat exchanger → Steam condensate tank; High-temperature steam user → High-temperature steam condensate line → Second condensate feed heat exchanger → First condensate feed heat exchanger → Steam condensate tank; Steam condensate tank → Condensate pump → Heat tracing station (differential pressure valve) → Second condensate feed heat exchanger → Plant steam condensate recovery system.

Claims

1. A device for preventing water hammer caused by steam condensation and for utilizing waste heat, characterized in that, The system includes a steam condensate tank, a first condensate feed heat exchanger, and a heat tracing station. A low-temperature steam condensate main pipe and a high-temperature steam condensate main pipe are provided to collect the low-temperature steam condensate and high-temperature steam condensate, respectively. The low-temperature steam condensate and high-temperature steam condensate exchange heat through the first condensate feed heat exchanger and then enter the steam condensate tank. The mixed condensate in the steam condensate tank is pumped to the heat tracing station by a condensate pump. The return water of the heat tracing station is connected to the condensate discharge pipeline. A differential pressure valve is installed between the inlet and outlet of the heat tracing station.

2. The steam condensate waterproofing hammer and waste heat utilization device according to claim 1, characterized in that, The device also includes a steam condensate tank venting heat exchanger, wherein the low-temperature steam condensate exchanges heat with the vented steam discharged from the top of the steam condensate tank before entering the condensate feed heat exchanger.

3. The steam condensate waterproofing hammer and waste heat utilization device according to claim 1, characterized in that, The device also includes a second condensate feed heat exchanger, through which the high-temperature steam condensate and the condensate discharged from the heat tracing station outlet exchange heat and are then connected to the condensate discharge pipeline.

4. The steam condensate waterproofing hammer and waste heat utilization device according to claim 1, characterized in that, The heat tracing station is equipped with a condensate inlet valve at the inlet and a condensate return valve at the outlet.

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