System for supplementing water to boiler by recovering waste heat of flash steam to produce hot water

Abstract

The utility model provides a system for supplying water to a boiler by recovering waste heat of flash steam to prepare hot water, relates to the technical field of waste heat recovery, and solves the problem that a large amount of heat energy is wasted due to the fact that high-temperature condensed water flash steam is directly discharged to the atmosphere in the existing production. The device comprises a 80 DEG C water tank, a 90 DEG C water tank and a flash recovery heat exchanger, the water outlet end of the 80 DEG C water tank is connected with the water inlet end of a secondary side heat exchanger of the flash recovery heat exchanger through a circulating water pipe, and the water outlet end of the secondary side heat exchanger of the flash recovery heat exchanger is connected with the water inlet end of the 90 DEG C water tank through a flash recovery heat exchange water outlet pipe. The primary side heat exchange water inlet end of the flash evaporation recovery heat exchanger is connected with the water outlet end of the condensate water recoverer through a condensate water supply pipe, and the water outlet end of the 90-DEG C water tank is connected with an original boiler room water supplementing tank through a hot water supplementing pipe. The utility model has the beneficial effects that the flash steam heat energy which cannot be utilized is converted into high-temperature hot water, and the water-saving function can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery, and particularly relates to a system for recovering flash steam waste heat to produce hot water for boiler make-up water. Background Art

[0002] In enterprises with steam systems, it is common to directly discharge the flash steam of high-temperature condensate, resulting in energy waste and increased production costs. It is extremely important to recover the heat of this part of the flash steam. For example, in battery production, there is a problem of discharging flash steam of high-temperature condensate in the condensate recovery of the cathode coating steam system. This part of the flash steam is directly discharged into the atmosphere, causing a large amount of heat energy waste and increasing the operating costs of enterprises. Content of the Utility Model

[0003] The purpose of the utility model is to solve the problem that in existing production, high-temperature condensate flash steam is directly discharged into the atmosphere, resulting in a large amount of heat energy waste.

[0004] To achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A system for recovering flash steam waste heat to produce hot water for boiler make-up water, characterized in that: it includes an 80°C water tank, a 90°C water tank and a flash steam recovery heat exchanger. The water inlet end of the 80°C water tank is connected to the soft water source of the boiler room through a soft water inlet pipe. The water outlet end of the 80°C water tank is connected to the water inlet end of the secondary side heat exchange of the flash steam recovery heat exchanger through a circulating water pipe. The water outlet end of the secondary side heat exchange of the flash steam recovery heat exchanger is connected to the water inlet end of the 90°C water tank through a flash steam recovery heat exchange outlet pipe. The water inlet end of the primary side heat exchange of the flash steam recovery heat exchanger is connected to the water outlet end of the condensate recovery device through a condensate supply pipe. The water outlet end of the primary side heat exchange of the flash steam recovery heat exchanger is connected to the water inlet end of the 90°C condensate water tank through a pipe. The water outlet end of the 90°C condensate water tank is connected to the water inlet end of the 90°C water tank through a condensate water circulation pipe. The water outlet end of the 90°C water tank is connected to the original boiler room make-up water tank through a hot water make-up pipe.

[0006] Further improvement is that: a communication pipe for balancing the liquid levels of the 80°C water tank and the 90°C water tank is connected in the middle of the 80°C water tank and the 90°C water tank.

[0007] Further improvement is that: a soft water make-up pump is connected to the soft water inlet pipe.

[0008] Further improvement is that: a circulating water pump is connected to the circulating water pipe.

[0009] Further improvement is that: a condensate water circulation pump is connected to the condensate water circulation pipe.

[0010] Further improvement: A hot water makeup pump is connected to the hot water makeup pipe.

[0011] Further improvement: It further includes a plate heat exchanger for producing 55°C hot water for heating. The circulating water pipe is connected to the heat medium inlet end of the plate heat exchanger through a circulating shunt pipe. The heat medium outlet end of the plate heat exchanger is connected to the inlet end of a 55°C water tank. The outlet end of the 55°C water tank is connected to the inlet end of a heating terminal through a heating water pipe, and a heating water pump is connected to the heating water pipe.

[0012] Further improvement: The outlet end of the heating terminal is connected to the cold medium inlet end of the plate heat exchanger, and the cold medium outlet end of the plate heat exchanger is connected to an 80°C water tank through a heat exchange coil.

[0013] Further improvement: Corresponding control water valves are provided on both the circulating water pipe and the circulating shunt pipe.

[0014] After adopting the above technical solution, the following beneficial effects are achieved compared with the existing technology:

[0015] The flash steam waste heat is recovered and reused through the flash steam recovery heat exchanger to produce 90 - 95°C hot water. The unusable flash steam heat energy is converted into high-temperature hot water, and the hot water is supplied to the required hot spots.

[0016] After the flash steam heat recovery, secondary condensate water is generated, and the secondary condensate water is continuously recycled to achieve the water-saving function.

[0017] A plate heat exchanger is added. Through the heat exchange of the plate heat exchanger, 55°C heating water is generated, increasing more utilization spaces and directions. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a schematic structural diagram of the system of the present invention.

[0020] Description of reference numerals: Soft water inlet pipe 1, soft water make-up pump 11, 80°C water tank 2, circulating water pipe 21, circulating water pump 22, circulating diversion pipe 23, flash steam recovery heat exchanger 3, flash steam recovery heat exchange outlet pipe 31, 90°C condensate water tank 4, condensate water circulation pipe 41, condensate water circulation pump 42, condensate water recovery device 5, condensate water supply pipe 51, 90°C water tank 6, hot water make-up pipe 61, hot water make-up pump 62, original boiler room make-up water tank 7, plate heat exchanger 8, 55°C water tank 9, heating water pipe 91, heating water pump 92, heating terminal 10. Detailed implementation manners

[0021] Refer to Figure 1 As shown, the technical solution adopted in this detailed implementation manner is: A flash steam waste heat recovery hot water production system for boiler make-up water, including an 80°C water tank 2, a 90°C water tank 6 and a flash steam recovery heat exchanger 3. The water inlet end of the 80°C water tank 2 is connected to the soft water source of the boiler room through a soft water inlet pipe 1. The water outlet end of the 80°C water tank 2 is connected to the water inlet end of the secondary side heat exchange of the flash steam recovery heat exchanger 3 through a circulating water pipe 21. The water outlet end of the secondary side heat exchange of the flash steam recovery heat exchanger 3 is connected to the water inlet end of the 90°C water tank 6 through a flash steam recovery heat exchange outlet pipe 31. The water inlet end of the primary side heat exchange of the flash steam recovery heat exchanger 3 is connected to the water outlet end of the condensate water recovery device 5 through a condensate water supply pipe 51. The water outlet end of the primary side heat exchange of the flash steam recovery heat exchanger 3 is connected to the water inlet end of the 90°C condensate water tank 4 through a pipe. The water outlet end of the 90°C condensate water tank 4 is connected to the water inlet end of the 90°C water tank 6 through a condensate water circulation pipe 41. The water outlet end of the 90°C water tank 6 is connected to the original boiler room make-up water tank 7 through a hot water make-up pipe 61.

[0022] Among them, a connecting pipe for balancing the liquid levels of the 80°C water tank 2 and the 90°C water tank 6 is connected to the middle of the 80°C water tank 2 and the 90°C water tank 6.

[0023] Among them, a soft water make-up pump 11 is connected to the soft water inlet pipe 1.

[0024] Among them, a circulating water pump 22 is connected to the circulating water pipe 21.

[0025] Among them, a condensate water circulation pump 42 is connected to the condensate water circulation pipe 41.

[0026] Among them, a hot water make-up pump 62 is connected to the hot water make-up pipe 61.

[0027] Among them, it also includes a plate heat exchanger 8 for producing hot water at 55°C for heating. The circulating water pipe 21 is connected to the heat medium inlet end of the plate heat exchanger 8 through a circulating shunt pipe 23. The heat medium outlet end of the plate heat exchanger 8 is connected to the inlet end of a 55°C water tank 9. The outlet end of the 55°C water tank 9 is connected to the inlet end of a heating terminal 10 through a heating water pipe 91, and a heating water pump 92 is connected to the heating water pipe 91.

[0028] Among them, the outlet end of the heating terminal 10 is connected to the cold medium inlet end of the plate heat exchanger 8, and the cold medium outlet end of the plate heat exchanger 8 is connected to an 80°C water tank 2 through a heat exchange coil.

[0029] Among them, corresponding control water valves are provided on both the circulating water pipe 21 and the circulating shunt pipe 23.

[0030] Among them, the condensate recovery device 5 is the condensate recovery device of the CF2 - cathode coating system.

[0031] Application of high - temperature condensate water in the CF2 - cathode coating system:

[0032] The steam consumption A of the cathode coater is 267t / day, the steam supply pressure is 6barg, and the condensate water temperature B is 135°C;

[0033] Discharged to atmospheric pressure 0barg, the condensate water temperature C is 100°C, and the steam enthalpy value D is 2257kJ / kg;

[0034] The flash steam quantity E=(B - C)*4.19kJ / kg / D*A = 17.35t / day;

[0035] The flash steam quantity E = 17.35t / 24h≈0.723t / h;

[0036] When the hot water is heated from 20°C to 90°C, the heat to be absorbed F=(90°C - 20°C)*4.19kJ / kg = 293.3kJ / kg;

[0037] The steam enthalpy value G contained in 0.723t / h of flash steam = 723kg / h*2257kJ / kg = 1631811kJ / h; converted to 453KW of heat;

[0038] The amount of hot water that can be heated H = G / F = 5.6t / h = 133.6T / D;

[0039] The waste heat of 453KW of the flash steam discharged can be converted into hot water heat energy through this process flow and completely recycled.

[0040] The recovered heat hot water can be used for the following purposes: providing high-temperature makeup water for the boiler to reduce the boiler energy consumption; heating the regeneration exhaust air of the rotary dehumidifier to reduce the electric energy or steam consumption and lower the energy consumption; providing heating for office buildings or other workshops with heating requirements in winter to reduce the energy consumption; providing heat sources for workshops with high-temperature environment requirements to supply heat energy; and other available directions, which can be applied according to the actual needs of the enterprise.

[0041] The working principle of the present utility model:

[0042] The low-temperature softened water (15 - 20 °C) in the boiler room is replenished into the 80 °C water tank through the soft water makeup pump. After the liquid levels of the 80 °C water tank and the 90 °C water tank are balanced, by starting the circulation pump, the softened water in the 80 °C water tank is transported to the secondary side of the flash recovery heat exchanger for heat exchange (the primary side of the flash recovery heat exchanger is the flash steam exhaust). After heat exchange, the softened water is supplied to the 90 °C water tank;

[0043] Through continuous circulation, the newly replenished low-temperature softened water can be heated to 80 °C. Thus, the 80 °C softened water can be heated to 90 °C through the flash recovery heat exchanger;

[0044] The high-temperature softened water in the 90 °C water tank is transported to the boiler makeup water tank or the deaerator through the water pump to achieve boiler makeup (high-temperature softened water);

[0045] The condensate generated by the flash of the primary side of the flash recovery heat exchanger due to heat exchange is first sent to the condensate water tank and then transported to the 90 °C water tank through the condensate water circulation pump for secondary recycling of the heat-carrying condensate water;

[0046] When the 90 °C water tank supplies water to the boiler room, the liquid level of the 80 °C water tank drops, and low-temperature softened water is continuously replenished (controlled by a float ball);

[0047] Additional utilization: During the soft water heat recovery cycle, 55 °C hot water can be produced through a plate heat exchanger to provide heating for office buildings, etc.

[0048] The above shows and describes the basic principle, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and explanations only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents. Those parts not detailed in the present utility model are all well-known technologies in the art.

Claims

1. A system for recovering waste heat from flash steam to produce hot water for boiler water replenishment, characterized in that: The invention comprises an 80℃ water tank, a 90℃ water tank and a flash recovery heat exchanger. The middle parts of the 80℃ water tank and the 90℃ water tank are connected with a connecting pipe for balancing the liquid levels of the 80℃ water tank and the 90℃ water tank. The water inlet end of the 80℃ water tank is connected to the soft water source of the boiler room through a soft water inlet pipe. The water outlet end of the 80℃ water tank is connected to the water inlet end of the secondary side heat exchange of the flash recovery heat exchanger through a circulating water pipe. The water outlet end of the secondary side heat exchange of the flash recovery heat exchanger is connected to the water outlet end of the secondary side heat exchange of the flash recovery heat exchanger through a circulating water pipe. The hot water outlet pipe is connected to the water inlet of the 90℃ water tank, the water inlet of the primary side heat exchange of the flash recovery heat exchanger is connected to the water outlet of the condensate recovery device through the condensate supply pipe, the water outlet of the primary side heat exchange of the flash recovery heat exchanger is connected to the water inlet of the 90℃ condensate water tank through a pipeline, the water outlet of the 90℃ condensate water tank is connected to the water inlet of the 90℃ water tank through the condensate circulation pipe, and the water outlet of the 90℃ water tank is connected to the original boiler room water supply tank through a hot water supply pipe.

2. A system for recovering waste heat from flash steam to produce hot water as a boiler water supply system according to claim 1, characterized in that: The soft water inlet pipe is connected with a soft water replenishment pump.

3. The system for recovering waste heat from flash steam to produce hot water as a boiler water supply system according to claim 1, characterized in that: The circulating water pipe is connected with a circulating water pump.

4. The system for recovering waste heat from flash steam to produce hot water as boiler water supply according to claim 1, characterized in that: The condensate circulation pipe is connected with a condensate circulation pump.

5. The system for recovering waste heat from flash steam to produce hot water as boiler water supply according to claim 1, characterized in that: The hot water replenishment pipe is connected with a hot water replenishment pump.

6. The system for recovering waste heat from flash steam to produce hot water as boiler water supply according to claim 1, characterized in that: It also includes a plate heat exchanger for producing 55°C hot water for providing heating. The circulating water pipe is connected to the thermal mass water inlet end of the plate heat exchanger through a circulating diversion pipe, the thermal mass water outlet end of the plate heat exchanger is connected to the water inlet end of a 55°C water tank, the water outlet end of the 55°C water tank is connected to the water inlet end of the heating terminal through a heating water pipe, and the heating water pipe is connected to a heating water pump.

7. A system for recovering waste heat from flash steam to produce hot water as boiler water supply according to claim 6, characterized in that: The water outlet of the heating terminal is connected to the cold water inlet of the plate heat exchanger, and the cold water outlet of the plate heat exchanger is connected to an 80°C water tank through a heat exchange coil.

8. The system for recovering waste heat from flash steam to produce hot water as boiler water supply according to claim 6, characterized in that: The circulating water pipe and the circulating diversion pipe are both provided with corresponding control water valves.

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