System for realizing automatic temperature control of marine urea cabin

Abstract

The utility model discloses a system for realizing automatic temperature control of a marine urea cabin. The system comprises a heat exchange pipe, a heating medium source, a refrigerant source, a temperature sensor and a controller, two ends of the heat exchange pipe are respectively connected with a first header pipe and a second header pipe; the first refrigerant branch pipe and the first heating medium branch pipe are connected to the first header pipe, and the second refrigerant branch pipe and the second heating medium branch pipe are connected to the second header pipe. The first refrigerant branch pipe, the first heating medium branch pipe, the second refrigerant branch pipe and the second heating medium branch pipe are each provided with an electric valve. The temperature sensor and the electric valve are both connected to the controller. Automatic switching between heating water and cooling water is achieved, manual operation is not needed, temperature adjustment is flexible, it is ensured that the temperature of the urea cabin is controlled within the normal storage temperature range, and operation and maintenance cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of ships, and particularly relates to a system for automatically controlling the temperature of a marine urea tank. Background Art

[0002] In order to meet the requirements of the International Maritime Organization for restricting the emissions of nitrogen oxides (NOx) from ships, at present, new-built ships and refitted ships mostly adopt selective catalytic reduction (SCR) technology to reduce NOx emissions. The SCR technology can achieve a maximum NOx emission reduction of up to 95%. Aqueous urea solution is widely used in marine SCR systems due to its advantages of high-efficiency denitrification, high safety, convenient storage and transportation, and cost-effectiveness. The specific process is that the urea solution is sprayed into the exhaust pipe as a reducing agent for the SCR reaction, decomposes into ammonia in the high-temperature exhaust gas, and selectively reduces NOx in the exhaust gas into pollution-free nitrogen and water under the action of a catalyst. The urea solution is stored in the urea tank on the ship, and the storage temperature requirements are relatively strict. When the solution temperature is lower than 5°C, crystals will precipitate and the solution concentration will decrease; when the solution temperature is higher than 35°C, urea is easily decomposed and deteriorated. Too high or too low storage temperature of the urea solution will interfere with the normal progress of the SCR reaction, reduce the denitrification efficiency, and the decomposition and deterioration of urea at high temperature will also cause no small losses to the shipowner. Therefore, it is necessary to control the temperature in the urea tank within the normal range, usually 5-35°C. Both the China Classification Society and the American Bureau of Shipping have requirements for configuring a necessary temperature control system for urea storage.

[0003] Traditional methods for heating the urea tank include boiler heating or electric heating. The former method requires increasing the boiler capacity for the urea tank, which is disadvantageous in terms of ship space, pipeline layout, and cost control; electric heating requires installing heating rods in the tank. Since the heating rods are smaller than the urea tank in size, the heating effect is not good, and there is also a problem of uneven heating.

[0004] Traditional cooling methods use seawater cooling. However, seawater is likely to cause pipeline corrosion, and the designed working temperature of seawater is usually 32°C, with a small heat transfer temperature difference and an unsatisfactory cooling effect. In extreme environments, the seawater temperature even reaches and exceeds 35°C, which cannot be used for cooling the urea tank. In addition, the existing temperature control methods for urea tanks are only single heating or cooling processes, with insufficient flexibility in temperature adjustment, and it is difficult to ensure that the temperature in the urea tank is within the normal range in the case of unstable ambient temperature or the ship changing its route.

[0005] The existing temperature control methods for marine urea tanks are only single heating or cooling processes, which cannot achieve flexible and effective temperature control of the urea tank, and simple control is likely to cause overcooling or overheating of the system temperature, affecting the quality of urea. Moreover, there are certain limitations in heating and cooling methods. For example, using electric heating will increase power consumption, and using seawater cooling is likely to cause pipeline corrosion and has an unsatisfactory cooling effect. Summary of the Utility Model

[0006] The technical problem to be solved by the utility model is to overcome the above defects existing in the prior art and provide a system for realizing automatic temperature control of a marine urea tank.

[0007] The utility model solves the above technical problem through the following technical solutions:

[0008] A system for realizing automatic temperature control of a marine urea tank includes a heat exchange pipe arranged in the urea tank, and further includes a heat medium source, a refrigerant source and a temperature sensor capable of detecting the temperature in the urea tank; both ends of the heat exchange pipe are respectively connected with a first main pipe and a second main pipe; the refrigerant outlet of the refrigerant source is connected with a first refrigerant branch pipe, and the heat medium outlet of the heat medium source is connected with a first heat medium branch pipe; the refrigerant inlet of the refrigerant source is connected with a second refrigerant branch pipe, and the heat medium inlet of the heat medium source is connected with a second heat medium branch pipe; both the first refrigerant branch pipe and the first heat medium branch pipe are connected to the first main pipe, and both the second refrigerant branch pipe and the second heat medium branch pipe are connected to the second main pipe; electric valves are arranged on the first refrigerant branch pipe, the first heat medium branch pipe, the second refrigerant branch pipe and the second heat medium branch pipe; the system for realizing automatic temperature control of the marine urea tank further includes a controller; the temperature sensor and the electric valves are both connected to the controller.

[0009] Further, the refrigerant source is the refrigerant water of an air-conditioning refrigeration system.

[0010] Further, the heat medium source is the main engine jacket water.

[0011] Further, the heat medium source is the low-temperature fresh water before the inlet of the low-temperature fresh water cooler.

[0012] Further, the electric valves and the controller are connected by a wireless communication method.

[0013] Further, the electric valves and the controller are connected by a cable.

[0014] Further, the temperature sensor and the controller are connected by a wireless communication method.

[0015] Further, the temperature sensor and the controller are connected by a cable.

[0016] Further, the electric valve is an electric remote control ball valve.

[0017] Further, a water inlet valve is arranged on the first main pipe.

[0018] The beneficial effects of the present utility model are as follows: The system for automatically controlling the temperature of the marine urea tank of the present utility model has both automatic heating and cooling functions. It realizes the heating or cooling of the urea tank through a set of devices, improves the heating and cooling methods, and adjusts the opening and closing of the valves of the heating / cooling working medium by setting temperature monitoring and control devices, so as to realize the automatic switching of heating water and cooling water without manual operation, with flexible temperature adjustment, ensuring that the temperature of the urea tank is controlled within the normal storage temperature range and reducing operation and maintenance costs. The present utility model uses jacket water as the heating working medium, making full use of the waste heat of the main engine, which is beneficial to energy conservation and emission reduction and reduces operation costs; it uses the refrigerant water of the air-conditioning refrigeration system as the cooling medium to achieve a full cooling effect and avoid the pipeline corrosion problem caused by using seawater cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of a preferred embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The following gives a preferred embodiment and combines the drawings to more clearly and completely illustrate the present utility model.

[0021] As Figure 1 shown, a system for automatically controlling the temperature of a marine urea tank includes a heat exchange pipe 13 provided in the urea tank 10, and further includes a heat medium source 30, a refrigerant source 20, and a temperature sensor 14 capable of detecting the temperature inside the urea tank. The temperature sensor 14 is provided inside the urea tank.

[0022] Both ends of the heat exchange pipe are respectively connected with a first main pipe 11 and a second main pipe 12. An inlet valve 16 is provided on the first main pipe 11.

[0023] The refrigerant outlet of the refrigerant source 20 is connected with a first refrigerant branch pipe 21, and the heat medium outlet of the heat medium source 30 is connected with a first heat medium branch pipe 31.

[0024] The refrigerant inlet of the refrigerant source 20 is connected with a second refrigerant branch pipe 22, and the heat medium inlet of the heat medium source 30 is connected with a second heat medium branch pipe 32.

[0025] Both the first refrigerant branch pipe 21 and the first heat medium branch pipe 31 are connected to the first main pipe 11, and both the second refrigerant branch pipe 22 and the second heat medium branch pipe 32 are connected to the second main pipe 12.

[0026] Electric valves 17 are provided on both the first refrigerant branch pipe 21, the first heat medium branch pipe 31, the second refrigerant branch pipe 22, and the second heat medium branch pipe 32.

[0027] The system for realizing automatic temperature control of a marine urea tank further includes a controller 15. The temperature sensor 14 and the electric valve 17 are both connected to the controller 15. The controller can be a temperature controller, or a temperature controller, or a programmable logic controller. The controller performs simple logical judgments. After receiving the temperature value measured by the temperature sensor, the controller compares the temperature value with a preset temperature value and issues a signal according to the comparison result. The controller is a common existing component and will not be elaborated here.

[0028] In this embodiment, the refrigerant source 20 is the chilled water of the air-conditioning refrigeration system; the heat medium source 30 is the main engine jacket water.

[0029] In other embodiments, the heat medium source can also be the low-temperature fresh water before the inlet of the low-temperature fresh water cooler. That is, when the diesel engine cannot provide the jacket water alone, the low-temperature fresh water before the inlet of the low-temperature fresh water cooler is used as the heat medium source to realize heating as an alternative solution.

[0030] The electric valve 17 and the controller 15 are connected by wireless communication; or, the electric valve and the controller are connected by a cable.

[0031] The temperature sensor 14 and the controller 15 are connected by wireless communication; or, the temperature sensor 14 and the controller 15 are connected by a cable.

[0032] In this embodiment, the electric valve is an electric remote control ball valve.

[0033] Figure 1 In, the arrow indicates the flow direction of the heat medium or refrigerant, and the connections between the temperature sensor and the controller and between the electric valve and the controller are represented by dotted lines.

[0034] Several temperature values can be preset in the controller. The temperature values preset in the controller can be the first set value, the second set value, the third set value, and the fourth set value respectively. After the temperature sensor measures the temperature, it transmits the signal of the temperature to the controller. The controller simply compares the temperature measured by the temperature sensor with the preset temperature value and issues a signal to the electric valve according to the comparison result, so that the electric valve opens or closes.

[0035] The working process of the system for realizing automatic temperature control of a marine urea tank according to the present invention includes the following steps:

[0036] Step 1, when the temperature measured by the temperature sensor is lower than the first set value, go to step 2; when the temperature measured by the temperature sensor is higher than the second set value, go to step 3; when the temperature measured by the temperature sensor is between the first set value and the second set value, the electric valves on the first refrigerant branch pipe, the first heat medium branch pipe, the second refrigerant branch pipe, and the second heat medium branch pipe are all closed.

[0037] In Step 1, the first set value is 5°C; the second set value is 35°C.

[0038] In Step 2, the controller sends signals to open the electric valves on the first and second hot medium branches, and close the electric valves on the first and second refrigerant branches; the hot medium from the hot medium source flows through the first hot medium branch, the first main pipe, the heat exchange pipe, the second main pipe, and the second hot medium branch in sequence; the heat exchange pipe heats the urea tank; until the temperature measured by the temperature sensor reaches the third set value, the controller sends signals to close the electric valves on the first and second hot medium branches, and stop heating the urea tank; return to Step 1.

[0039] In Step 2, the third set value is 8°C.

[0040] In Step 3, the controller sends signals to open the electric valves on the first and second refrigerant branches, and close the electric valves on the first and second hot medium branches; the refrigerant from the refrigerant source flows through the first refrigerant branch, the first main pipe, the heat exchange pipe, the second main pipe, and the second refrigerant branch in sequence, and the heat exchange pipe cools the urea tank; until the temperature measured by the temperature sensor reaches the fourth set value, the controller sends signals to close the electric valves on the first and second refrigerant branches, and stop cooling the urea tank; return to Step 1.

[0041] In Step 3, the fourth set value is 32°C.

[0042] Thus, it can automatically control the temperature of the urea tank within the normal storage temperature range, that is, automatically control the temperature of the urea tank at 5 - 35°C, preventing urea from deteriorating or crystallizing.

[0043] The present utility model uses jacket water as the heating working medium, making full use of the waste heat of the main engine, which is beneficial to energy conservation and emission reduction and reduces operating costs; uses the refrigerant water of the air conditioning refrigeration system as the cooling medium to achieve a full cooling effect and avoid the pipeline corrosion problem caused by using seawater cooling.

[0044] The system for automatically controlling the temperature of the marine urea tank of the present utility model has both automatic heating and cooling functions, realizes the heating or cooling of the urea tank through a set of devices, improves the heating and cooling methods, and realizes the automatic switching of heating water and cooling water by setting a temperature monitoring and control device to adjust the opening and closing of the valves of the heating / cooling working medium, without manual operation, with flexible temperature adjustment, so as to ensure that the temperature of the urea tank is controlled within the normal storage temperature range and reduce operating and maintenance costs.

[0045] Although the specific embodiments of the present utility model have been described above, those skilled in the art should understand that this is only an example, and the protection scope of the present utility model is defined by the appended claims. Without departing from the principle and essence of the present utility model, those skilled in the art can make various changes or modifications to these embodiments, but these changes and modifications all fall within the protection scope of the present utility model.

Claims

1. A system for realizing automatic temperature control of a marine urea tank, comprising a heat exchange pipe arranged in the urea tank, characterized in that: It also includes a heat medium source, a cold medium source and a temperature sensor capable of detecting the temperature in the urea tank; the two ends of the heat exchange tube are respectively connected to the first main pipe and the second main pipe; the cold medium outlet of the cold medium source is connected to the first cold medium branch pipe, and the hot medium outlet of the hot medium source is connected to the first hot medium branch pipe; the cold medium inlet of the cold medium source is connected to the second cold medium branch pipe, and the hot medium inlet of the hot medium source is connected to the second hot medium branch pipe; the first cold medium branch pipe and the first hot medium branch pipe are both connected to the first main pipe, and the second cold medium branch pipe and the second hot medium branch pipe are both connected to the second main pipe; the first cold medium branch pipe, the first hot medium branch pipe, the second cold medium branch pipe and the second hot medium branch pipe are all provided with electric valves; the system for realizing automatic temperature control of the marine urea tank also includes a controller; the temperature sensor and the electric valve are both connected to the controller.

2. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The refrigerant source is the refrigerant water of the air conditioning refrigeration system.

3. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The heat medium source is the main engine cylinder jacket water.

4. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The heat medium source is the low-temperature fresh water before the inlet of the low-temperature fresh water cooler.

5. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The electric valve and the controller are connected via wireless communication.

6. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The electric valve and the controller are connected via cables.

7. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The temperature sensor and the controller are connected via wireless communication.

8. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The temperature sensor and the controller are connected via a cable.

9. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: The electric valve is an electric remote-controlled ball valve.

10. The system for realizing automatic temperature control of marine urea tank according to claim 1, characterized in that: A water inlet valve is arranged on the first main pipe.

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