High-temperature hot water heating system of hot press

Abstract

The invention belongs to the technical field of heat supply, and particularly relates to a hot press high-temperature hot water heating system which comprises a first water storage tank, a second water storage tank, a hot press, a cooling water pond, a high-temperature cooling water tank, a heat pump device, a heat supply circulating pump, a heat preservation circulating pump, a cooling water circulating pump, a condenser circulating pump and an evaporator circulating pump. The first water storage tank and the second water storage tank are connected with compressed air, the pressure in the water storage tanks is always higher than the saturation pressure of hot water, and water boiling is avoided, so that the situation that the water pump cannot supply water due to the fact that a steam pocket enters the water pump is avoided, and safe and stable operation of the water pump is guaranteed; before the hot press is used, water is heated to the needed temperature through steam, a large amount of instant gas in the heating process of the hot press is converted into long-time small-flow gas through the method, the problems that in the heating stage, boiler gas supply is insufficient, and steam is wasted in the heat preservation stage are solved, and meanwhile the stability of boiler steam supply can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of heat supply, and particularly relates to a high-temperature hot water heating system for a hot press. Background Art

[0002] When using a hot press to produce products, it is usually divided into three stages, namely the heating stage, the heat preservation stage, and the cooling stage. Heating generally uses steam heating. Since the equipment temperature is low, high-temperature steam immediately condenses when it enters the equipment. In this stage, the instantaneous steam flow rate is very large, which easily causes a short-term shortage of boiler gas supply. In the heat preservation stage, the steam inlet valve is closed, and when the temperature is lower than the set value, a short-term air supply is carried out. The gas consumption in this stage is less. Due to the limited regulation ability of the boiler, the steam generated by the boiler in this stage cannot be utilized in time, resulting in steam waste. In the cooling stage, a large amount of cold water is required to cool the equipment. The cooling water is cooled by a cooling tower and then flows back to the reservoir for the next cooling use. There is heat waste and the phenomenon of too high cooling water temperature in summer in this stage.

[0003] Steam is generally used to heat hot water by using a heat exchanger, and the condensed water returns to the boiler through a make-up water pump. Heating with a heat exchanger is slow on the one hand, and on the other hand, the heat cannot be fully utilized, resulting in energy waste. When the temperature exceeds 100°C, the hot water in the water storage tank becomes saturated water. When the temperature of the heat exchanger is higher than the water temperature, the water inside is in a boiling state for a long time. If the bubbles in the water enter the water pump, it is easy to cause the water pump to stop pumping water.

[0004] Moreover, some hot presses use saturated water to supply heat to the hot press. Since the saturated water is in a boiling state during the heating process, on the one hand, the noise is very loud, and on the other hand, due to the existence of a large number of bubbles, bubbles often enter during the operation of the water pump, resulting in problems such as insufficient water supply capacity of the water pump and severe shaking of the equipment.

[0005] The invention designs a high-temperature hot water heating system for a hot press to solve the above problems. Summary of the Invention

[0006] In order to achieve the above object, the invention adopts the following technical solutions: A high-temperature hot water heating system for a hot press, which comprises: a first water storage tank, a second water storage tank, a hot press, a cooling water tank, a high-temperature cooling water tank, a heat pump device, a heating circulation pump, a heat preservation circulation pump, a cooling water circulation pump, a condenser circulation pump, and an evaporator circulation pump; The first water storage tank is used for storing high-temperature unsaturated water heated by steam. The first water storage tank is connected to the water outlet of the hot press through a first valve, and the first water storage tank is connected to the water inlet of the heating circulation pump through a second valve; The second water storage tank is used to store high-temperature hot water heated by the heat pump device. The second water storage tank is connected to the water outlet of the hot press through the third valve, the second water storage tank is connected to the heat supply circulation pump through the fourth valve, and the second water storage tank is connected to the heat pump device; The heat supply circulation pump is connected to the water inlet of the hot press through the fifth valve, the water outlet of the hot press is connected to the heat preservation circulation pump through the sixth valve, and the heat preservation circulation pump is connected to the water inlet of the hot press through the seventh valve; The water inlet of the cooling water tank is connected to the water outlet of the hot press through the eighth valve, and the water outlet of the cooling water tank is connected to the water inlet of the cooling water circulation pump through the ninth valve; The water inlet of the high-temperature cooling water tank is connected to the water outlet of the hot press through the tenth valve, the high-temperature cooling water tank is connected to the water inlet of the cooling water circulation pump through the eleventh valve, and the water outlet of the cooling water circulation pump is connected to the water inlet of the hot press through the twelfth valve.

[0007] As a preferred solution, the heat pump device is provided with a heat pump condenser water inlet, a heat pump condenser water outlet, a heat pump evaporator water inlet, and a heat pump evaporator water outlet. The second water storage tank is connected to the heat pump condenser water inlet through the condenser circulation pump, the second water storage tank is connected to the heat pump condenser water outlet, the cooling water tank is connected to the heat pump evaporator water inlet through the evaporator circulation pump, and the cooling water tank is connected to the heat pump evaporator water outlet.

[0008] As a preferred solution, a steam valve and a steam-water mixer assembled together are installed on the first water storage tank, and a first pressure reducing valve, a first compressed air valve, and a first one-way valve assembled together are installed on the first water storage tank.

[0009] As a preferred solution, a second pressure reducing valve, a second compressed air valve, and a second one-way valve assembled together are installed on the second water storage tank.

[0010] As a preferred solution, a first safety valve, a first water replenishing valve, a first thermometer, a first pressure gauge, a first liquid level gauge, and a first blowdown valve are respectively installed on the first water storage tank.

[0011] As a preferred solution, a second safety valve, a second water replenishing valve, a second thermometer, a second pressure gauge, a second liquid level gauge, and a second blowdown valve are respectively installed on the second water storage tank.

[0012] Compared with the existing technology, the advantages of the present invention are as follows: 1. The first water storage tank and the second water storage tank of the present invention are connected to compressed air, and the pressure inside the water storage tank is always higher than the hot water saturation pressure, avoiding water boiling, thus preventing the steam drum from entering the water pump and causing the water pump to be unable to supply water, ensuring the safe and stable operation of the water pump. In addition, by using high-temperature hot water heating instead of steam heating, before the hot press is used, steam is used to heat the water to the required temperature. After the hot press starts to work, a small flow of steam is continuously used to heat the water. By this method, the instantaneous large amount of gas consumption during the temperature rise process of the hot press is converted into small flow gas consumption for a long time, solving the problem of insufficient boiler gas supply during the temperature rise stage and steam waste during the heat preservation stage, and at the same time improving the stability of the boiler steam supply.

[0013] 2. The present invention adopts a high-temperature heat pump heat recovery technology and a multi-stage heating scheme. The heat of the cooling water is transferred to the second water storage tank through a high-temperature heat pump. After the cooling water is preheated, the hot water in the secondary water storage tank is used for heating. After the temperature reaches the set temperature, the hot water in the first water storage tank is used for heating, effectively improving the energy utilization rate and reducing the production cost.

[0014] 3. The present invention has a function of cooling water recovery and cooling water preheating. When the hot press is cooled, the high-temperature water is stored in the high-temperature cooling water storage tank. When the hot press starts to be heated, the hot water in the high-temperature cooling water storage tank is first used to preheat the hot press, making full use of the heat in the cooling water, reducing energy consumption, improving the energy utilization rate, and reducing the production cost.

[0015] 4. The present invention directly mixes with water through a steam-water mixer, which can not only solve the uneven heating problem through a heat exchanger, but also make full use of the sensible heat of the steam condensate, avoiding the waste of heat caused by the direct discharge of the condensate through a steam trap. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the system structure of the present invention.

[0017] Figure 2 is a schematic diagram of the first water storage tank of the present invention.

[0018] Figure 3 is a schematic diagram of the second water storage tank of the present invention.

[0019] Figure 4 is a schematic diagram of the heat pump device of the present invention.

[0020] Names of the reference numerals in the figure: 1. First water storage tank; 2. Second water storage tank; 3. Hot press; 4. Cooling water pool; 5. High-temperature cooling water tank; 6. First pressure reducing valve; 7. First compressed air valve; 8. First check valve; 9. Steam valve; 10. Steam-water mixer; 11. Second pressure reducing valve; 12. Second compressed air valve; 13. Second check valve; 14. First valve; 15. Second valve; 16. Third valve; 17. Fourth valve; 18. Heating circulation pump; 19. Fifth valve; 20. Sixth valve; 21. Heat preservation circulation pump; 22. Seventh valve; 23. Twelfth valve; 24. Cooling water circulation pump; 25. Eighth valve; 26. Tenth valve; 27. Ninth valve; 28. Eleventh valve; 29. Condenser circulation pump; 30. Evaporator circulation pump; 31. Heat pump device; 3101. Inlet of heat pump condenser; 3102. Outlet of heat pump condenser; 3103. Inlet of evaporator; 3104. Outlet of heat pump evaporator; 101. First safety valve; 102. First water replenishing valve; 103. First thermometer; 104. First pressure gauge; 105. First liquid level gauge; 106. First blowdown valve; 201. Second safety valve; 202. Second water replenishing valve; 203. Second thermometer; 204. Second pressure gauge; 205. Second liquid level gauge; 206. Second blowdown valve. Specific embodiments

[0021] The following will further describe in detail the specific embodiments of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments or drawings are used to illustrate the present invention, but not to limit the scope of the present invention.

[0022] A high-temperature hot water heating system for a hot press, as Figures 1 to 4 shown, includes a first water storage tank 1, a second water storage tank 2, a hot press 3, a cooling water pool 4, a high-temperature cooling water tank 5, a heat pump device 31, a heating circulation pump 18, a heat preservation circulation pump 21, a cooling water circulation pump 24, a condenser circulation pump 29, and an evaporator circulation pump 30; The first water storage tank 1 is used to store high-temperature unsaturated water heated by steam. The first water storage tank 1 is connected to the outlet of the hot press 3 through the first valve 14, and the first water storage tank 1 is connected to the inlet of the heating circulation pump 18 through the second valve 15; The second water storage tank 2 is used to store high-temperature hot water heated by the heat pump device 31. The second water storage tank 2 is connected to the outlet of the hot press 3 through the third valve 16, the second water storage tank 2 is connected to the heating circulation pump 18 through the fourth valve 17, and the second water storage tank 2 is connected to the heat pump device 31; The heat supply circulation pump 18 is connected to the water inlet of the hot press 3 through the fifth valve 19. The water outlet of the hot press 3 is connected to the heat preservation circulation pump 21 through the sixth valve 20. The heat preservation circulation pump 21 is connected to the water inlet of the hot press 3 through the seventh valve 22; The water inlet of the cooling water tank 4 is connected to the water outlet of the hot press 3 through the eighth valve 25. The water outlet of the cooling water tank 4 is connected to the water inlet of the cooling water circulation pump 24 through the ninth valve 27; The water inlet of the high-temperature cooling water tank 5 is connected to the water outlet of the hot press 3 through the tenth valve 26. The high-temperature cooling water tank 5 is connected to the water inlet of the cooling water circulation pump 24 through the eleventh valve 28. The water outlet of the cooling water circulation pump 24 is connected to the water inlet of the hot press 3 through the twelfth valve 23.

[0023] The first water storage tank and the second water storage tank are connected to compressed air. The pressure in the water storage tank is always higher than the hot water saturation pressure, avoiding water boiling, thus preventing the steam drum from entering the water pump and causing the water pump to be unable to supply water, ensuring the safe and stable operation of the water pump.

[0024] In addition, by using high-temperature hot water heating instead of steam heating, before the hot press is used, the water is first heated to the required temperature by steam. After the hot press starts to work, a small flow of steam is continuously used to heat the water. By this method, the instantaneous large amount of gas used during the heating-up process of the hot press is converted into small-flow gas used for a long time, solving the problem of insufficient boiler gas supply during the heating-up stage and steam waste during the heat preservation stage, and at the same time improving the stability of the boiler steam supply.

[0025] Adopting the high-temperature heat pump heat recovery technology and the multi-stage heating scheme, the heat of the cooling water is transferred to the second water storage tank through the high-temperature heat pump. After the cooling water is preheated, the hot water in the secondary water storage tank is used for heating. After the temperature reaches the set temperature, the hot water in the first water storage tank is used for heating, effectively improving the energy utilization rate and reducing the production cost.

[0026] When the hot press is cooled, the high-temperature water is stored in the high-temperature cooling water storage tank. When the hot press starts to be heated, the hot water in the high-temperature cooling water storage tank is first used to preheat the hot press, making full use of the heat in the cooling water, reducing energy consumption, improving the energy utilization rate, and reducing the production cost.

[0027] During the heating process of the hot press, multi-stage heating is adopted for heating. The first-stage heating uses the high-temperature cooling water in the early stage of cooling for heating. The second-stage heating uses the hot water heated by the high-temperature heat pump for heating. The third-stage heating uses the hot water heated by steam for heating.

[0028] After the hot press is cooled by cooling water, the water temperature of the cooling water pool rises. The high-temperature heat pump uses the warm water in the cooling water pool as a heat source to heat the water in the second water storage tank, generating high-temperature hot water for use in the next heating. At the same time, the temperature of the cooling water is reduced to a temperature that can be used for cooling for the next cooling use, reducing energy costs while improving energy utilization efficiency.

[0029] As Figure 1 and Figure 4 shown, the heat pump device 31 is provided with a heat pump condenser water inlet 3101, a heat pump condenser water outlet 3102, a heat pump evaporator water inlet 3103, and a heat pump evaporator water outlet 3104. The second water storage tank 2 is connected to the heat pump condenser water inlet 3101 through a condenser circulation pump 29, and the second water storage tank 2 is connected to the heat pump condenser water outlet 3102. The cooling water pool 4 is connected to the heat pump evaporator water inlet 3103 through an evaporator circulation pump 30, and the cooling water pool 4 is connected to the heat pump evaporator water outlet 3104.

[0030] As Figure 2 shown, a steam valve 9 and a steam-water mixer 10 are assembled and installed on the first water storage tank 1. A first pressure reducing valve 6, a first compressed air valve 7, and a first one-way valve 8 are assembled and installed on the first water storage tank 1. A second pressure reducing valve 11, a second compressed air valve 12, and a second one-way valve 13 are assembled and installed on the second water storage tank 2.

[0031] By directly mixing with water through the steam-water mixer, the situation of uneven heating through the heat exchanger can be solved, and the sensible heat of the steam condensate can be fully utilized, avoiding the waste of heat caused by the direct discharge of the condensate through the steam trap.

[0032] As Figure 2 and Figure 3 shown, a first safety valve 101, a first water replenishing valve 102, a first thermometer 103, a first pressure gauge 104, a first liquid level gauge 105, and a first blowdown valve 106 are respectively installed on the first water storage tank 1. A second safety valve 201, a second water replenishing valve 202, a second thermometer 203, a second pressure gauge 204, a second liquid level gauge 205, and a second blowdown valve 206 are respectively installed on the second water storage tank 2.

[0033] There are no specific requirements for the structure of each water storage tank, and any container that meets the relevant regulations can be used as a water storage tank; there are no specific regulations on the type and structure of each valve, and any valve that can achieve the same function can be used. There are no specific requirements for each water pump, and any water pump that can meet the water supply requirements can be used. There are no specific requirements for each high-temperature heat pump, and any heat pump that can generate high-temperature hot water can be used.

[0034] Working principle: When the system is used for the first time, heat an appropriate amount of clean water in the first water storage tank 1 through the first water replenishing valve 102. Open the steam valve 9 and heat the water in the first water storage tank 1 to the temperature required by the second water storage tank 2 with steam. Then open the second valve 15 and the fourth valve 17, and open the first compressed air valve 7. Compressed air enters the first water storage tank 1 successively through the first pressure reducing valve 6, the first compressed air valve 7, and the first one-way valve 8. Under the action of the gravity of the water and the pressure of the compressed air, transfer the hot water in the first water storage tank 1 to the second water storage tank 2; After the transfer of the hot water in the first water storage tank 1 is completed, open the first valve 14, the eighth valve 25, and the first water replenishing valve 102. While releasing the pressure in the first water storage tank 1, continue to add an appropriate amount of clean water to the first water storage tank 1. Then close the first valve 14 and the eighth valve 25, open the steam valve 9, and after the steam heats the water in the first water storage tank 1 to the temperature required by the second water storage tank 2 again, close the steam valve 9.

[0035] After the hot press 3 is started, open the twelfth valve 23, the eighth valve 25, and the eleventh valve 28. The high-temperature cooling water in the high-temperature cooling water tank 5 is pumped into the hot press 3 by the cooling water circulation pump 24. The high-temperature cooling water exchanges heat with the hot press 3 to preheat the hot press 3. The hot water after preheating flows into the cooling water pool 4 through the valve 25.

[0036] After the hot water in the high-temperature cooling water tank 5 is used up, close the twelfth valve 23, the eighth valve 25, the eleventh valve 28, and the cooling water circulation pump 24. Open the fourth valve 17, the heat supply circulation pump 18, and the fifth valve 19.

[0037] When the liquid level in the second water storage tank 2 is higher than the set value, open the tenth valve 26, and the excess hot water is stored in the high-temperature cooling tank 5 after passing through the hot press 3; When the liquid level in the second water storage tank 2 reaches or is lower than the set liquid level, close the valve 26 and open the valve 16. The hot water circulates between the second water storage tank 2 and the hot press 3.

[0038] When the temperature difference between the hot press 3 and the water temperature in the second water storage tank 2 is less than the preset value, open the second valve 15 and close the fourth valve 17. In this state, if the liquid level in the first water storage tank 1 is higher than the set value, the excess hot water is stored in the second water storage tank 2 after passing through the hot press 3 until the liquid level in the first water storage tank 1 drops to the set value. Then close the third valve 16 and open the first valve 14. The hot water circulates between the first water storage tank 1 and the hot press 3.

[0039] When the water temperature in the first water storage tank 1 is lower than the set value, open the steam valve 9 and heat the hot water in the first water storage tank 1 with steam.

[0040] After the temperature in the hot press 3 is heated to the set temperature, turn off the heating circulation pump 18, the first valve 14, and the second valve 15, and open the sixth valve 20, the seventh valve 22, and the insulation circulation pump 21. The hot water remaining in the hot press 3 continuously circulates between the water inlet and the water outlet of the hot press 3 through the insulation circulation pump 21, making the temperature inside the hot press 3 more uniform.

[0041] In the insulation stage, if the temperature of the hot press 3 is lower than the water replenishment temperature, turn on the heating circulation pump 18, the first valve 14, and the second valve 15 again. After the temperature of the hot press 3 reaches the set temperature, turn off the heating circulation pump 18, the first valve 14, and the second valve 15.

[0042] When the hot press 3 enters the cooling stage, turn off the sixth valve 20, the seventh valve 22, the fifth valve 19, and the insulation circulation pump 21, and open the twelfth valve 23, the tenth valve 26, the ninth valve 27, and the cooling water circulation pump 24. The cooling water in the cooling water tank 4 is pumped into the hot press 3, and the high-temperature hot water in the hot press 3 in the early stage of cooling is stored in the high-temperature cooling water tank 5; When the water temperature at the water outlet of the hot press 3 is lower than the set value, close the tenth valve 26, open the eighth valve 25, and at the same time start the heat pump system 31, open the condenser circulation pump 29 and the evaporator circulation pump 30 until the water temperature in the condensation water tank 4 is lower than the set temperature, then turn off the heat pump system 31, and turn off the condenser circulation pump 29 and the evaporator circulation pump 30.

[0043] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Any simple modification or equivalent change made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A high-temperature hot water heating system for a hot press, characterized in that, Including: A first water storage tank (1), a second water storage tank (2), a hot press (3), a cooling water pool (4), a high-temperature cooling water tank (5), a heat pump device (31), a heat supply circulation pump (18), a heat preservation circulation pump (21), a cooling water circulation pump (24), a condenser circulation pump (29), and an evaporator circulation pump (30); The first water storage tank (1) is used for storing high-temperature unsaturated water heated by steam. The first water storage tank (1) is connected to the water outlet of the hot press (3) through a first valve (14), and the first water storage tank (1) is connected to the water inlet of the heat supply circulation pump (18) through a second valve (15); The second water storage tank (2) is used for storing high-temperature hot water heated by the heat pump device (31). The second water storage tank (2) is connected to the water outlet of the hot press (3) through a third valve (16), the second water storage tank (2) is connected to the heat supply circulation pump (18) through a fourth valve (17), and the second water storage tank (2) is connected to the heat pump device (31); The heat supply circulation pump (18) is connected to the water inlet of the hot press (3) through a fifth valve (19). The water outlet of the hot press (3) is connected to the heat preservation circulation pump (21) through a sixth valve (20), and the heat preservation circulation pump (21) is connected to the water inlet of the hot press (3) through a seventh valve (22); The water inlet of the cooling water pool (4) is connected to the water outlet of the hot press (3) through an eighth valve (25), and the water outlet of the cooling water pool (4) is connected to the water inlet of the cooling water circulation pump (24) through a ninth valve (27); The water inlet of the high-temperature cooling water tank (5) is connected to the water outlet of the hot press (3) through a tenth valve (26). The high-temperature cooling water tank (5) is connected to the water inlet of the cooling water circulation pump (24) through an eleventh valve (28), and the water outlet of the cooling water circulation pump (24) is connected to the water inlet of the hot press (3) through a twelfth valve (23).

2. The high-temperature hot water heating system of a hot press according to claim 1, characterized in that: The heat pump device (31) is provided with a heat pump condenser water inlet (3101), a heat pump condenser water outlet (3102), a heat pump evaporator water inlet (3103), and a heat pump evaporator water outlet (3104). The second water storage tank (2) is connected to the heat pump condenser water inlet (3101) through the condenser circulation pump (29), the second water storage tank (2) is connected to the heat pump condenser water outlet (3102), the cooling water pool (4) is connected to the heat pump evaporator water inlet (3103) through the evaporator circulation pump (30), and the cooling water pool (4) is connected to the heat pump evaporator water outlet (3104).

3. A high-temperature hot water heating system for a hot press according to claim 1, characterized in that: A steam valve (9) and a steam-water mixer (10) assembled together are installed on the first water storage tank (1). A first pressure reducing valve (6), a first compressed air valve (7), and a first one-way valve (8) assembled together are installed on the first water storage tank (1).

4. A high-temperature hot water heating system for a hot press according to claim 3, characterized in that: A second pressure reducing valve (11), a second compressed air valve (12), and a second one-way valve (13) assembled together are installed on the second water storage tank (2).

5. A high-temperature hot water heating system for a hot press according to claim 1, characterized in that: A first safety valve (101), a first water replenishing valve (102), a first thermometer (103), a first pressure gauge (104), a first liquid level gauge (105), and a first blowdown valve (106) are respectively installed on the first water storage tank (1).

6. The high-temperature hot water heating system of a hot press according to claim 5, characterized in that: A second safety valve (201), a second water replenishing valve (202), a second thermometer (203), a second pressure gauge (204), a second liquid level gauge (205), and a second blowdown valve (206) are respectively installed on the second water storage tank (2).

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