Waste water heat energy recovery system for leaching workshop

Abstract

The utility model provides a waste water heat energy recovery system for a leaching workshop, which relates to the technical field of heat energy recycling and comprises a leaching workshop water distribution tank, a waste water heat exchanger, a waste water temporary storage tank, a waste water cooking tank, a waste water pump, a filter and an air preheater, wastewater guided out by the wastewater pipeline of the leaching workshop water distribution box is guided into a shell of the wastewater heat exchanger. High-temperature treated hot wastewater is introduced into a pipeline in the wastewater heat exchanger, and the wastewater introduced into a shell of the wastewater heat exchanger through a shell pass inlet can be heated, so that the use amount of steam required for heating the wastewater entering the wastewater cooking pot by the wastewater cooking pot is reduced; and the air is heated by the air preheater so as to convey the hot air to the evapo-separated machine for drying and dehydrating the materials, so that the hot wastewater after high-temperature treatment can be purified, the use of water vapor can be reduced, and the purpose of reducing the cost is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat energy recovery and utilization, in particular to a heat energy recovery system for wastewater in a leaching workshop. Background Art

[0002] The main vegetable oil processing technologies are: mechanical method, aqueous method, and leaching method. Among them, the leaching method has been widely used due to its advantages such as high oil efficiency, low processing cost, large-scale production, low labor intensity, and good product quality. At present, when the conventional leaching method is used to produce vegetable oil, a certain amount of hot wastewater (about 90°C) will be generated in the workshop. Some small oil plants choose to directly discharge the hot wastewater into the water seal tank and send it to the sewage treatment section after the water temperature cools down.

[0003] In general technology, large-scale oil plants will add a wastewater heat exchanger to exchange hot wastewater with cold wastewater (about 40°C), utilize part of its heat, and then directly discharge it into the water seal tank. After the hot water heat exchange, the temperature can be reduced to about 65°C, but the temperature is still high and still contains a lot of heat. If this heat is directly discharged, it will cause energy waste. Some manufacturers also need to add additional equipment to cool the wastewater, which increases costs. Utility Model Content

[0004] The utility model aims to provide a leaching workshop wastewater heat energy recovery system, aiming to solve the problem of insufficient heat utilization of hot wastewater in the leaching workshop wastewater heat energy recovery system in general technology, resulting in increased costs.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: the wastewater heat energy recovery system of the leaching workshop comprises a leaching workshop water distribution tank, a wastewater heat exchanger, a wastewater temporary storage tank, a wastewater cooking tank, a wastewater pump, a filter and an air preheater; the wastewater discharged from the wastewater pipeline of the leaching workshop water distribution tank is introduced into the inside of the shell of the wastewater heat exchanger; the wastewater inside the shell of the wastewater heat exchanger is directly introduced into the wastewater cooking tank for heating; the high-temperature wastewater heated by the wastewater cooking tank is introduced into the filter via the wastewater pump; the high-temperature wastewater filtered by the filter is introduced into the inside of the pipe of the wastewater heat exchanger; the high-temperature hot wastewater inside the pipe of the wastewater heat exchanger exchanges heat with the wastewater entering the shell and then enters the air preheater; the air preheater heats the air and transports it to the degassing machine.

[0006] The beneficial effect is that by introducing high-temperature treated hot wastewater into the pipe inside the wastewater heat exchanger, the wastewater introduced into the wastewater heat exchanger shell through the shell inlet can be heated, thereby reducing the amount of steam required for the wastewater cooking tank to heat the wastewater entering the wastewater, and the high-temperature wastewater after heat exchange is introduced into the air preheater, so that the air is heated by the air preheater to transport the hot air to the degassing machine for drying and dehydrating the material, which can not only purify the high-temperature treated hot wastewater, but also reduce the use of water vapor, thereby achieving the purpose of reducing costs.

[0007] A further technical solution of the utility model is that the shell of the wastewater heat exchanger has a shell-side inlet and a shell-side outlet, and the pipeline of the wastewater heat exchanger has a tube-side inlet and a tube-side outlet.

[0008] A further technical solution of the utility model is that a bypass valve is installed inside the pipeline before the shell side inlet, and the bypass valve is connected to the wastewater boiling tank.

[0009] The beneficial effect is: since hot wastewater contains a small amount of impurities, during long-term production, direct entry of hot wastewater into the wastewater heat exchanger for heat exchange may cause blockage of the heat exchanger. The hot wastewater can skip the wastewater heat exchanger and directly enter the wastewater cooking tank to avoid affecting the filtration treatment of the wastewater.

[0010] A further technical solution of the utility model is that both the wastewater cooking tank and the wastewater temporary storage tank are provided with a bottom slag discharge port.

[0011] A further technical solution of the utility model is that the wastewater heated in the wastewater cooking tank enters into the wastewater temporary storage tank through the overflow port.

[0012] A further technical solution of the utility model is that a thermometer and a liquid level sensor are installed in the wastewater temporary storage tank, and the liquid level sensor is connected to the wastewater pump signal.

[0013] The beneficial effect is that the liquid level sensor is used to start the wastewater pump to pump water when the wastewater level in the wastewater temporary storage tank exceeds a first set value, and stop the wastewater pump when the liquid level in the wastewater temporary storage tank is lower than a second set value, so as to avoid idling of the wastewater pump and wasting resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a system diagram of the utility model.

[0015] In the figure: 1-water distribution tank in leaching workshop, 2-wastewater heat exchanger, 3-wastewater temporary storage tank, 4-wastewater cooking tank, 5-wastewater pump, 6-filter, 7-air preheater. DETAILED DESCRIPTION

[0016] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1 As shown, a leaching workshop wastewater heat energy recovery system includes a leaching workshop water distribution tank 1, a wastewater heat exchanger 2, a wastewater temporary storage tank 3, a wastewater cooking tank 4, a wastewater pump 5, a filter 6 and an air preheater 7. The wastewater heat exchanger 2 has a shell side inlet, a shell side outlet, a tube side inlet and a tube side outlet. The pipeline of the wastewater heat exchanger 2 stores purified high-temperature clean wastewater. In this specific embodiment, the temperature of the high-temperature clean wastewater is 90°C. The wastewater discharged from the wastewater pipeline of the leaching workshop water distribution tank 1 enters the shell of the wastewater heat exchanger 2 via the first connecting pipe and the shell side inlet in sequence. In this specific embodiment, the temperature of the wastewater discharged from the wastewater pipeline of the leaching workshop water distribution tank 1 is 40°C, and a bypass valve is installed inside the first connecting pipe.

[0018] The shell outlet and the bypass valve are interconnected with the inlet of the wastewater cooking tank 4, so that when the shell of the wastewater heat exchanger 2 is blocked, the wastewater can be directly introduced into the wastewater cooking tank 4 for treatment through the bypass valve. The wastewater entering the wastewater cooking tank 4 is directly heated by steam to remove a small amount of solvent contained in the wastewater. The heated wastewater enters the wastewater temporary storage tank 3 through the overflow port of the wastewater cooking tank 4. The wastewater cooking tank 4 and the wastewater temporary storage tank 3 are both provided with a bottom slag discharge port, which can regularly discharge the waste slag at the bottom of the tank body.

[0019] The wastewater in the wastewater storage tank 3 is introduced into the filter 6 for filtration via the wastewater pump 5. A thermometer and a liquid level sensor are installed in the wastewater storage tank 3. The liquid level sensor is used to start the wastewater pump 5 to pump water when the wastewater level in the wastewater storage tank 3 exceeds a first set value, and stop the wastewater pump 5 when the liquid level in the wastewater storage tank 3 is lower than a second set value, so as to avoid idling of the wastewater pump 5 and waste resources. It can be imagined that the first set value is much larger than the second set value. The wastewater storage tank 3 is also provided with an overflow pipe, which can automatically overflow into the outdoor water seal pool when the wastewater is full.

[0020] The filter 6 removes most of the impurities in the wastewater, and the impurities are automatically discharged to the outdoor water seal pool through the slag discharge port at the bottom of the filter 6. In the present embodiment, the filter 6 is a self-cleaning filter. It is conceivable that the filter can be replaced with a bag filter or other filtering equipment with equivalent functions. The filtered high-temperature clean wastewater enters the pipeline of the wastewater heat exchanger 2 from the tube side inlet after the flow rate is adjusted by the flow meter. The high-temperature wastewater entering the pipeline is heat exchanged with the low-temperature wastewater entering the shell of the wastewater heat exchanger 2 from the shell side inlet and then discharged through the tube side outlet (at this time, the temperature of the high-temperature clean wastewater is reduced, and the low-temperature wastewater is heated and introduced into the wastewater cooking tank 4 through the shell side outlet for treatment). Subsequently, the high-temperature wastewater in the pipeline is introduced into the air preheater 7 and heat-exchanged with the air entering the interior thereof. The air preheater 7 transports the heated air inside the air preheater 7 to the dehumidifier in the workshop via a drying fan for drying and dehydrating the material.

[0021] In a specific embodiment, taking the processing of a soybean oil plant with a daily processing capacity of 1,000 tons as an example, the amount of 40°C wastewater discharged from the water distribution tank 1 of the leaching workshop is 3,300 kg / h. After the wastewater heat exchanger 2 and the 90°C wastewater discharged from the wastewater temporary storage tank 3 are heat exchanged, the temperature rises to 60°C, and the 90°C hot wastewater is cooled to about 65°C. After the 65°C wastewater is heat exchanged with the air entering the air preheater 7, the air volume of the degassing machine drying fan is 20,000 m3 / h. When the outdoor temperature is 25°C, the outdoor air is heated by the air preheater 7, and the air temperature rises to 35°C. The temperature of the hot wastewater after heat exchange drops to about 38°C. The area of ​​the air preheater 7 is 200m2, so that the entire system can save about 265kg / h of steam, which has considerable economic benefits.

[0022] In the utility model, by introducing high-temperature treated hot wastewater into the pipe inside the wastewater heat exchanger 2, the wastewater introduced into the shell of the wastewater heat exchanger 2 through the shell inlet can be heated, thereby reducing the amount of steam required for the wastewater cooking tank 4 to heat the wastewater entering the inside, and the high-temperature wastewater after heat exchange is introduced into the air preheater 7, so that the air is heated by the air preheater 7 to transport the hot air to the degassing machine for drying and dehydrating the material. Not only can the high-temperature treated hot wastewater be purified, but also the use of water vapor can be reduced, thereby achieving the purpose of reducing costs.

Claims

1. A leaching workshop wastewater heat recovery system, characterized in that: The invention comprises a water distribution tank (1) of a leaching workshop, a wastewater heat exchanger (2), a wastewater temporary storage tank (3), a wastewater boiling tank (4), a wastewater pump (5), a filter (6) and an air preheater (7). The wastewater discharged from the wastewater pipeline of the water distribution tank (1) of the leaching workshop is introduced into the shell of the wastewater heat exchanger (2). The wastewater in the shell of the wastewater heat exchanger (2) is directly introduced into the wastewater boiling tank (4) for heating. The high-temperature wastewater heated by the wastewater boiling tank (4) is introduced into the filter (6) via the wastewater pump (5). The high-temperature wastewater filtered by the filter (6) is introduced into the pipe of the wastewater heat exchanger (2). The high-temperature hot wastewater in the pipe of the wastewater heat exchanger (2) exchanges heat with the wastewater entering the shell and then enters the air preheater (7). The air preheater (7) heats the air and transports it to the degassing machine.

2. A leaching workshop wastewater heat recovery system according to claim 1, characterized in that: The shell of the wastewater heat exchanger (2) has a shell-side inlet and a shell-side outlet, and the pipeline of the wastewater heat exchanger (2) has a tube-side inlet and a tube-side outlet.

3. A leaching workshop wastewater heat recovery system according to claim 2, characterized in that: A bypass valve is installed inside the pipeline before the shell side inlet, and the bypass valve is connected to the wastewater boiling tank (4).

4. A leaching workshop wastewater heat recovery system according to claim 1, characterized in that: The wastewater cooking tank (4) and the wastewater temporary storage tank (3) are both provided with bottom slag discharge ports.

5. The leaching workshop wastewater heat energy recovery system according to claim 1 is characterized in that: The wastewater heated in the wastewater boiling tank (4) enters the wastewater temporary storage tank (3) through the overflow port.

6. A leaching workshop wastewater heat recovery system according to claim 1, characterized in that: A thermometer and a liquid level sensor are installed in the wastewater temporary storage tank (3), and the liquid level sensor is connected to the wastewater pump (5) by signal.

7. The leaching workshop wastewater heat recovery system according to claim 1 is characterized in that: The wastewater temporary storage tank (3) is also provided with an overflow pipe for allowing overflowing wastewater to overflow into an outdoor water seal pool.

8. A leaching workshop wastewater heat recovery system according to any one of claims 1 to 7, characterized in that: The bottom of the filter (6) is provided with a slag discharge port for automatically discharging impurities into an outdoor water seal pool.

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