Heat supply system for heating materials in wet anaerobic jar

Abstract

The utility model discloses a heat supply system for heating materials in a wet anaerobic tank. The heat supply system comprises a heat exchanger, a water supply loop and a slurry loop, the heat exchanger is arranged outside the anaerobic tank and comprises an inner tube and an outer tube arranged on the outer wall of the inner tube in a sleeving manner, the two ends of the inner tube pass are communicated with the slurry loop, and the inner tube pass conveys slurry in the heat exchanger from bottom to top; the two ends of the outer tube pass communicate with a water supply loop, the outer tube pass conveys water from top to bottom in the heat exchanger, and the inner tube pass and the outer tube pass conduct countercurrent flow heat exchange so that the temperature of slurry in the inner tube pass can be increased. The water supply loop comprises a hot water source, a first valve, an electric control valve, a first liquid inlet pipeline, a second valve, an outer tube pass of the heat exchanger, a third valve, a fourth valve, a filter, a hot water circulating pump, a check valve and a fifth valve which are connected in sequence and then returns to the hot water source; the slurry loop comprises an anaerobic tank, a seventh valve, a slurry circulating pump, an inner tube pass of the heat exchanger and a sixth valve and then returns to the anaerobic tank.

Description

Technical Field

[0001] The utility model relates to the field of heating devices, in particular to a heating system for heating materials in a wet anaerobic tank for kitchen waste or kitchen waste. Background Art

[0002] The optimal temperature for mesophilic fermentation in existing anaerobic tanks is 39±1°C. The conventional heating method is to heat the slurry directly in the tank using steel pipes or direct steam injection heating. The main disadvantages of using steel pipes to heat the slurry directly in the tank are: the heating pipes are laid directly in the anaerobic tank, which has low heat exchange efficiency, resulting in a slow slurry heating rate and reduced production efficiency; the slurry contains corrosive media such as hydrogen sulfide, which will corrode the heating pipes over long periods of time, reducing their service life; and once the pipes are damaged, they are difficult to repair and replace. Although direct steam injection heating has high heating efficiency, it will increase the slurry volume, reduce the slurry concentration, and reduce gas production to a certain extent; and the steam directly enters the system, increasing the amount of biogas slurry and thus increasing the operating costs of the back-end biogas slurry treatment. Summary of the Invention

[0003] The present utility model aims to overcome the shortcomings of the prior art and provides a heating system for heating the contents of a wet anaerobic tank containing food waste or kitchen waste. The heating system comprises a double-tube heat exchanger disposed outside the anaerobic tank. The system draws slurry from the anaerobic tank into the inner tube of the double-tube heat exchanger. Hot water at a predetermined temperature is then transported from the outer tube of the double-tube heat exchanger to the inner tube. The slurry is then transported upward through the inner tube of the double-tube heat exchanger, forming a countercurrent heat exchange with the hot water transported downward through the outer tube. After the slurry is heated, it returns to the anaerobic tank. A stirrer disposed within the anaerobic tank evenly distributes the heat to the slurry, thereby raising the temperature of the slurry to a predetermined temperature and completing the heating of the slurry within the anaerobic tank. It eliminates the problem of heating pipes being directly immersed in the material and corroding quickly; it also avoids direct steam injection and the amount of water brought into the system. In addition, the slurry and hot water exchange heat in countercurrent in the shell-and-tube heat exchanger, which increases the heat exchange efficiency.

[0004] A heating system for heating materials in a wet anaerobic tank comprises a heat exchanger, a water supply circuit, and a slurry circuit. The heat exchanger is disposed outside the anaerobic tank and is a double-tube heat exchanger comprising an inner tube and an outer tube sleeved on the outer wall of the inner tube. Both ends of the inner tube are connected to the slurry circuit, and the inner tube transports slurry from bottom to top within the heat exchanger. Both ends of the outer tube are connected to the water supply circuit, and the outer tube transports water from top to bottom within the heat exchanger. The inner and outer tubes exchange heat in countercurrent to increase the temperature of the slurry within the inner tube.

[0005] The water supply circuit includes a hot water source, a first valve, an electric regulating valve, a first liquid inlet pipeline, a second valve, an outer pipe of a heat exchanger, a third valve, a fourth valve, a filter, a hot water circulation pump, a check valve 5, and a fifth valve connected in sequence and then returns to the hot water source;

[0006] The water temperature of the hot water source is 70-90°C;

[0007] The slurry loop includes an anaerobic tank, a seventh valve, a slurry circulation pump, an inner pipe of a heat exchanger, and returns to the anaerobic tank after the sixth valve;

[0008] The heating system further comprises a temperature sensor, which is arranged at the top of the anaerobic tank and is used to monitor the temperature of the slurry in the anaerobic tank.

[0009] Furthermore, the electric regulating valve is electrically connected to a temperature sensor for performing PID control according to a temperature value of the temperature sensor to adjust the opening of the electric regulating valve.

[0010] Furthermore, the check valve is used to protect the operation of the hot water circulation pump; the first valve is used to open or close when the electric regulating valve is under maintenance; the second valve and the third valve are control valves for the inlet / outlet of the heat exchanger; the sixth valve and the seventh valve are control valves for the inlet / outlet of the anaerobic tank slurry, respectively.

[0011] Furthermore, the heat exchanger includes an outer tube water inlet, an inner tube water outlet, an inner tube water inlet and an outer tube water outlet; wherein the outer tube water inlet and the inner tube water outlet are arranged adjacent to each other, and the inner tube water inlet and the outer tube water outlet are arranged adjacent to each other.

[0012] Furthermore, the second valve is connected to the outer tube water inlet of the heat exchanger, and the outer tube water outlet is connected to the third valve; the outlet of the slurry circulation pump is connected to the inner tube water inlet, and the inner tube water outlet is connected to the sixth valve.

[0013] Furthermore, the inner tubes of the heat exchanger are connected at the elbows by means of pipe clamps. If the tubes are blocked due to excessive viscosity of the slurry, they can be easily disassembled and cleaned, and are easy to install. Quick disassembly and installation will not affect production.

[0014] The heating system is particularly suitable for treating restaurant food or kitchen waste.

[0015] Compared with the prior art, the utility model is particularly suitable for wet anaerobic systems in the food waste treatment industry. The heat exchanger is arranged outside the anaerobic tank to avoid accelerated corrosion caused by direct contact with the slurry.

[0016] Moreover, the slurry and hot water exchange heat in a countercurrent manner in the shell-and-tube heat exchanger, which increases the heat exchange efficiency and thus improves the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the heating system of the present invention.

[0018] in,

[0019] C-101: heat exchanger; C-102: shell; DIG: anaerobic tank; TT-101: temperature sensor;

[0020] 1: Agitator; 2: Slurry circulation pump; 3: Hot water circulation pump; 4: Electric regulating valve;

[0021] 5: Check valve; 6: Filter; 11: First valve; 12: Second valve; 13: Third valve;

[0022] 14: fourth valve; 15: fifth valve; 16: sixth valve; 17: seventh valve;

[0023] 19: First liquid inlet pipeline; 20: External pipe water inlet; 21: Internal pipe water outlet;

[0024] 22: Inner pipe water inlet; 23: Outer pipe water outlet; 24: Eighth valve; 25: Ninth valve. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The specific embodiments described are only used to explain the present invention and are not intended to limit the present invention.

[0026] like Figure 1 As shown, a heating system for heating materials in a wet anaerobic tank for food waste or kitchen waste includes a heat exchanger C-101, a temperature sensor TT-101, a water supply circuit, and a slurry circuit. The heat exchanger C-101 is enclosed by a housing C-102, which is an insulated shell to reduce heat loss. The heat exchanger C-101 is a double-tube heat exchanger, comprising a sleeved outer tube and inner tube, which are laid in an S-shape within the housing C-102. The water inlet and water outlet of the heat exchanger C-101 extend out of the housing C-102. The heat exchanger C-101 includes an outer tube water inlet 20, an inner tube water outlet 21, an inner tube water inlet 22, and an outer tube water outlet 23. The outer tube water inlet 20 and the inner tube water outlet 21 are positioned adjacent to each other, and the inner tube water inlet 22 and the outer tube water outlet 23 are positioned adjacent to each other.

[0027] Moreover, the inner pipes of the heat exchanger are connected at the elbows by means of pipe clamps. If the pipes are blocked due to excessive viscosity of the slurry, they can be easily disassembled and cleaned. It is also easy to install, and quick disassembly and installation will not affect production.

[0028] The temperature sensor TT-101 is arranged at the top of the anaerobic tank DIG to monitor the slurry temperature in the anaerobic tank DIG, and the temperature sensor TT-101 is electrically connected to a programmable controller.

[0029] The various components of the heating system are connected by pipes, including the water supply circuit and the slurry circuit. The specific connections are as follows:

[0030] Water supply circuit: The hot water source is connected to one end of the first valve 11 via a pipeline. The other end of the first valve 11 is connected to the liquid inlet of the electric control valve 4. The outlet of the electric control valve 4 is connected to the first liquid inlet pipeline 19. The outlet of the first liquid inlet pipeline 19 is connected to one end of the second valve 12. The other end of the second valve 12 is connected to the external pipe inlet 20 of the heat exchanger C-101. The external pipe outlet 23 of the heat exchanger C-101 is connected to the third valve 13, the fourth valve 14, the filter 6, the hot water circulation pump 3, the check valve 5, and the fifth valve 15 in sequence, and then connected to the return water of the heating room via a pipeline. The flow rate and speed of the slurry circulation pump 2 and the hot water circulation pump 3 are set according to actual needs.

[0031] Slurry circuit: The inner tube water outlet 21 of the heat exchanger C-101 is connected to one end of the sixth valve 16 through a pipeline via the eighth valve 24 (this valve is a valve provided with the heat exchanger and is closed when the heat exchanger is not in use or under maintenance). The other end of the sixth valve 16 is connected to the water inlet of the anaerobic tank DIG. The slurry outlet of the anaerobic tank DIG is connected in sequence to the seventh valve 17 and the slurry circulation pump 2 and then enters the inner tube water inlet 22 through the ninth valve 25.

[0032] The slurry transported by the inner tube side of the heat exchanger is transported from bottom to top through the inner tube side of the double-tube heat exchanger, and forms a countercurrent heat exchange with the hot water transported from top to bottom by the outer tube side, and the slurry is heated and then returned to the anaerobic tank.

[0033] The electric regulating valve 4 is electrically connected to a temperature sensor for PID control based on the temperature value of the temperature sensor to adjust the opening of the electric regulating valve 4. In the water supply circuit and slurry circuit, all valves except the electric regulating valve 4 are manual valves. The check valve 5 is used to protect the operation of the hot water circulation pump 3. The first valve 11, second valve 12, third valve 13, fourth valve 14, and fifth valve 15 are all butterfly valves. The first valve 11 is used to open or close during maintenance of the electric regulating valve 4. The second valve 12 and third valve 13 are control valves for the water inlet and outlet of the heat exchanger C-101. The sixth valve 16 and seventh valve 17 are control valves for the DIG slurry inlet and outlet of the anaerobic tank, respectively.

[0034] When the heating system is operating, all valves in the heat exchanger's water supply circuit are open. Hot water (85°C supply temperature) from the heating room flows through the pipeline, sequentially passing through the first valve 11, the electric regulating valve 4, the second liquid inlet pipe 19, the second valve 12, and the outer pipe inlet 20 of the heat exchanger C-101 before entering the outer pipe side of the heat exchanger. After heat exchange in the heat exchanger C-101, the hot water flows out and the return water passes through the outer pipe outlet 23, the third valve 13, the fourth valve 14, the filter 6, the hot water circulation pump 3, the check valve 5, and the fifth valve 15 before being transported back to the heating room. The return water temperature to the heating room is approximately 75°C.

[0035] All valves of the slurry circuit are open; the slurry from the anaerobic tank flows out from the slurry outlet on the side wall of the tank, passes through the seventh valve 17, the slurry circulation pump 2, the ninth valve 25, and the inner tube water inlet 22 of the heat exchanger C-101, and then enters the inner tube side of the heat exchanger. After the slurry exchanges heat with the hot water in the outer tube in the heat exchanger C-101, it flows out through the inner tube water outlet 21 of the heat exchanger C-101, and is then transported to the anaerobic tank DIG through the eighth valve 24, the sixth valve 16, and the slurry inlet of the anaerobic tank DIG.

[0036] During this process, the slurry absorbs the heat of the hot water and diffuses the heat evenly to all the slurry in the anaerobic tank through the agitator 1 in the anaerobic tank (the anaerobic tank DIG is also provided with an agitator 1), thereby heating the slurry in the anaerobic tank to the specified temperature, completing the heating of the slurry in the anaerobic tank.

[0037] During the heating process, the temperature sensor TT-101 monitors the slurry temperature in the anaerobic tank DIG and transmits the temperature value to its PID controller in real time. The temperature sensor and the electric regulating valve 4 on the water supply pipe form PID control. When the temperature reaches a preset high temperature value, the PID controller controls the electric regulating valve 4 to open smaller, thereby reducing the input heat; when the anaerobic tank temperature drops to a preset low temperature value, the electric regulating valve opens wider, thereby increasing the input heat, thereby keeping the slurry in the anaerobic tank at the target temperature.

[0038] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the scope of protection of the present invention.

Claims

1. A heating system for heating materials in a wet anaerobic tank, characterized in that: The invention comprises a heat exchanger (C-101), a water supply circuit, and a slurry circuit; the heat exchanger (C-101) is arranged outside the anaerobic tank (DIG) and is a shell-and-tube heat exchanger, comprising an inner tube and an outer tube sleeved on the outer wall of the inner tube, the two ends of the inner tube side being connected to the slurry circuit, and the inner tube side transports slurry from bottom to top in the heat exchanger; the two ends of the outer tube side being connected to the water supply circuit, and the outer tube side transports water from top to bottom in the heat exchanger, and the inner tube side and the outer tube side perform countercurrent heat exchange to heat the slurry inside the inner tube side; The water supply circuit includes a hot water source, a first valve (11), an electric regulating valve (4), a first liquid inlet pipeline (19), a second valve (12), an outer pipe of a heat exchanger, a third valve (13), a fourth valve (14), a filter (6), a hot water circulation pump (3), a check valve (5), and a fifth valve (15) connected in sequence, and then returns to the hot water source; The water temperature of the hot water source is 70-90°C; The slurry loop includes the anaerobic tank (DIG), the seventh valve (17), the slurry circulation pump (2), the inner pipe of the heat exchanger, and the sixth valve (16) before returning to the anaerobic tank (DIG); The heating system further comprises a temperature sensor (TT-101), which is arranged at the top of the anaerobic tank (DIG) and is used to monitor the slurry temperature in the anaerobic tank (DIG).

2. The heating system for heating materials in a wet anaerobic tank according to claim 1, characterized in that: The electric regulating valve (4) is electrically connected to a temperature sensor for performing PID control in accordance with a temperature value of the temperature sensor to adjust the opening of the electric regulating valve (4).

3. The heating system for heating materials in a wet anaerobic tank according to claim 1, characterized in that: The check valve (5) is used to protect the operation of the hot water circulation pump (3); the first valve (11) is used to open or close when the electric regulating valve (4) is under maintenance; the second valve (12) and the third valve (13) are control valves for the water inlet / outlet of the heat exchanger (C-101); the sixth valve (16) and the seventh valve (17) are control valves for the slurry inlet / outlet of the anaerobic tank (DIG), respectively.

4. The heating system for heating materials in a wet anaerobic tank according to claim 1, characterized in that: The heat exchanger (C-101) comprises an outer tube water inlet (20), an inner tube water outlet (21), an inner tube water inlet (22) and an outer tube water outlet (23); wherein the outer tube water inlet (20) and the inner tube water outlet (21) are arranged adjacent to each other, and the inner tube water inlet (22) and the outer tube water outlet (23) are arranged adjacent to each other.

5. The heating system for heating materials in a wet anaerobic tank according to claim 4, characterized in that: The second valve (12) is connected to the outer pipe water inlet (20) of the heat exchanger (C-101), and the outer pipe water outlet (23) is connected to the third valve (13); the outlet of the slurry circulation pump (2) is connected to the inner pipe water inlet (22), and the inner pipe water outlet (21) is connected to the sixth valve (16).

6. The heating system for heating materials in a wet anaerobic tank according to claim 1, characterized in that: The inner pipes of the heat exchanger are connected at the elbows by means of pipe clamps.

Images