JP5455564B2 - Heating medium boiler - Google Patents

Description

  The present invention relates to a heat medium boiler that heats a heat medium oil by performing combustion and supplies heat by circulating the heated heat medium oil with a heat using part.

  Heat transfer medium oil heating is performed by having a cylindrical combustion chamber with a coiled heat transfer medium heating tube with a space in the center and upper and lower ends insulated by a refractory material and burning in the combustion chamber. Heat medium boilers for heating the heat medium oil in the pipe are widely used. In the heat medium boiler, a heat medium oil circulation pipe is connected between the heat use part and heat is supplied to the heat use part by circulating the heat medium oil. Circulation of the heat medium oil is performed by installing a circulation pump in a boiler inlet pipe that feeds the heat medium oil returned from the heat use section into the heat medium boiler and operating the circulation pump. By heating the heat medium boiler and operating the circulation pump, the heated high temperature heat medium oil is sent to the heat use part, and the heat medium oil whose temperature is lowered by releasing heat at the heat use part is Heat is supplied by circulating the heat medium back to the heat medium boiler.

  In the case of a heat medium boiler, as described in JP-A-6-341606, heat is stored in the refractory material during combustion of the heat medium boiler, and even if the combustion is stopped, the heat generated from the refractory material is used as heat medium oil. Sometimes it is heated. If the flow of the heat transfer oil is stopped at this time, the heat transfer oil in a place where the heat of the refractory material is easily received may be deteriorated (carbonized) by being overheated. During the heat supply operation by the heat medium boiler, the circulation pump is operated regardless of the presence or absence of combustion, so the heat medium oil will not be overheated, but the heat supply boiler is no longer needed and the operation of the heat medium boiler is stopped If the circulating pump is stopped simultaneously with the operation stop, the heat transfer oil is overheated. For this reason, when the operation of the heat medium boiler is stopped, it is necessary to perform a cooling operation until the temperature of the boiler sufficiently decreases. In JP-A-6-341606, an elapsed time and a heating medium temperature after stopping combustion are detected, a blower and a circulation pump are used until a predetermined time has elapsed after the boiler has stopped and the heating medium temperature is equal to or lower than a preset temperature. This prevents the heat medium oil from deteriorating.

  However, operating the circulation pump when heat is not being supplied means that the amount of power consumption increases accordingly, so wasteful power consumption is prevented while preventing deterioration of the heat transfer oil. It was hoped to suppress it.

JP-A-6-341606

  The problem to be solved by the present invention is to prevent the heat transfer oil from being overheated when the operation is stopped in the heat transfer boiler, and to suppress an increase in power consumption.

The invention according to claim 1 has a cylindrical combustion chamber in which a side surface is formed by a coiled heat transfer oil heating tube having a space in the center, and upper and lower ends are thermally insulated with a refractory material, and heated heat In a heat medium boiler that supplies medium oil to a heat use part, wherein the heat medium oil is circulated by providing a circulation pump in a heat medium oil pipe connecting the heat use part and the heat medium boiler. , A rotation speed changing device for changing the rotation speed of the circulation pump and a refractory material temperature detection device for detecting the temperature of the refractory material of the heat medium boiler are provided and circulated during the heat medium oil cooling operation after the heat medium boiler operation is stopped. When the pump is operated, the heat is controlled until the temperature of the refractory material detected by the refractory material temperature detection device is lowered to the set value, so that the rotational speed of the circulating pump is lower than during operation of the heat medium boiler. Medium boiler.

  In the case of the cooling operation of the heating medium oil after the heating medium boiler operation is stopped, the heating medium oil keeps flowing slowly by operating the circulating pump with the circulating pump rotating at a low speed. Is not partially overheated and deteriorated, and since the rotation speed of the circulation pump is low, the power consumption of the circulation pump can be reduced. In addition, by detecting that the temperature of the refractory material has decreased to a predetermined temperature and stopping the operation of the circulation pump, the circulation pump will stop too early, leading to deterioration of the heat transfer oil, It is possible to prevent wasteful power consumption by operating for a long time.

Flow diagram of heat medium boiler and heat using part implementing the present invention

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flow diagram of three heat medium boilers and heat use units installed in parallel. The heat medium boiler 1 has a cylindrical combustion chamber having a side surface formed by a coil-shaped heat medium oil heating tube 3 having a space in the center, and supplies the heated heat medium oil to the heat use unit 2. . The heat-medium boiler 1 has a combustion device in the upper center portion, and heats the heat-medium oil in the heat-medium oil heating tube 3 by performing combustion from the combustion device toward the combustion chamber. A refractory material 5 is installed at the upper and lower portions of the combustion chamber and is insulated by the refractory material 5.

  Each heat medium boiler 1 is provided with an operation control device 8, and the operation of the heat medium boiler 1 is controlled by the operation control device 8. The heat generated in the heat medium boiler 1 is transferred through the heat medium oil so that the heat medium oil can circulate between the heat use unit 2 and the heat medium boiler 1. In each heat medium boiler 1, heat medium oil is sent out through an individual boiler outlet pipe 13, and the boiler outlet pipe 13 is connected to a common heat medium oil collecting pipe 11. The heat medium oil collecting pipe 11 is connected to the heat using part 2, and the high-temperature heat medium oil sent from the heat medium boiler 1 is sent to the heat using part 2 through the heat medium oil collecting pipe 11. The heat medium oil deprived of heat in the heat use section 2 is returned to each heat medium boiler 1 through a common heat medium oil distribution pipe 12 and boiler inlet pipe 14, and the heat medium oil distribution pipe 12 and each heat medium boiler. 1 is connected by a boiler inlet pipe 14. The circulation pump 4 is provided in the boiler inlet pipe 14 after branching to each heat medium boiler 1.

  The circulation pump 4 is provided with an inverter device 6 as a rotation speed changing device so that the rotation speed of the circulation pump 4 can be adjusted by the inverter device 6. Further, a refractory material temperature detection device 7 for detecting the temperature of the refractory material 5 portion of the heat medium boiler 1 is provided, and the refractory material temperature detected by the refractory material temperature detection device 7 is output to the operation control device 8. deep.

  The plurality of heat medium boilers 1 installed adjusts the output by increasing or decreasing the number of combustion based on the load status. Based on the heat medium oil temperature detecting device 9 for detecting the heat medium oil temperature in the heat medium oil collecting pipe 11 and the heat medium oil temperature detected by the heat medium oil temperature detecting device 9, the number of combustion of the heat medium boiler 1 is determined. The number control device 10 is provided to reduce the output amount by decreasing the number of combustion when the temperature of the heat medium oil becomes high, and increase the number of combustion when the temperature of the heat medium oil becomes low. This controls the number of units that increase the output. When a combustion request signal is output from the number control device 10 to the operation control device 8 of the heat medium boiler 1, the operation control device 8 operates each part of the heat medium boiler 1 to perform combustion, and the combustion request signal is output. When interrupted, the combustion of the heat medium boiler 1 is stopped.

  By performing the combustion in the heat medium boiler 1, the heat medium oil heating pipe 3 in the combustion chamber of the heat medium boiler is heated, and the heat medium oil in the heat medium oil heating pipe is heated. At this time, the circulation pump 4 operates at the rated capacity, and sends the heated high-temperature heat transfer oil to the heat use unit 2. While the circulating pump 4 is operating, the heat medium oil always flows in the heat medium oil heating pipe 3, and the heated heat medium oil is the heat medium oil heating pipe 3, boiler outlet pipe 13, heat It is sent to the heat using part 2 through the medium oil collecting pipe 11. The high-temperature heat transfer oil sent to the heat use unit 2 is deprived of heat by the heat use unit 2 to lower the temperature, and the low-temperature heat transfer oil returns to the heat transfer boiler 1.

  When the amount of heat used in the heat using unit 2 decreases, the amount of temperature decrease in the heat medium oil in the heat using unit 2 decreases, so the temperature of the heat medium oil rises and is detected by the heat medium oil temperature detection device 9. The temperature of the heat transfer oil increases. In the number control device 10, when the amount of heat supplied is excessive and the temperature of the heat medium oil becomes high, the number of combustion of the heat medium boiler 1 is decreased. In the heat medium boiler to which the combustion stop command is sent from the number control device 10, the combustion is stopped. In this case, in the boiler in which the combustion is stopped, the combustion is stopped but is not excluded from the number control target, and the operation state is continued. At this time, since the supply of heat by the heat medium boiler continues, the circulation pump continues to operate at the rated capacity, and the heat medium oil is not overheated.

  When this is an operation stop to turn off the operation switch of the heat medium boiler, the heat supply from the heat medium boiler is stopped, so that it is not necessary to operate the circulation pump. However, when the refractory material temperature detected by the refractory material temperature detection device 7 at this time is higher than a predetermined temperature, the operation of the circulation pump 4 is continued to prevent overheating of the heat transfer oil. However, when the operation is stopped, the operation of the circulation pump 4 is performed by reducing the number of rotations by the inverter device 6 and reducing the circulation amount of the heat transfer oil than during the operation.

  The deterioration of the heat transfer oil that occurs while the operation of the heat transfer boiler 1 is stopped is because the heat transfer oil does not move, the heat from the refractory material 5 is concentrated at a specific location, and the heat transfer oil temperature is increased to a higher temperature than usual. It is caused by overheating, and deterioration of the heat transfer oil can be prevented by flowing the heat transfer oil to eliminate the concentration of heat. The flow of the heat medium oil necessary in this case is only for preventing the heat medium oil from being overheated. Therefore, the flow amount of the heat medium oil may be less than the flow amount when the heat is transmitted to the heat use unit 2. It is possible to reduce the power consumption of the circulation pump 4 by reducing the number of rotations.

  The operation of the circulation pump 4 performed while the operation of the heat medium boiler is stopped is performed until the temperature of the refractory material 5 detected by the refractory material temperature detection device 7 decreases to a predetermined temperature. The temperature of the heat using part 2 and the temperature of the heat transfer oil may be subject to short-term fluctuations under the influence of the surroundings. In particular, when the number of rotations of the circulation pump 4 is reduced, a variation occurring in the heat transfer oil temperature is likely to occur as compared with a normal number of rotations. Therefore, if the operation of the circulation pump 4 is determined based on the temperature of the heat use part or the heat transfer oil, the operation of the circulation pump 4 may be continued more than necessary or the necessary operation may not be performed. It was. In the case of the refractory material 5, short-term temperature fluctuations due to the influence of the surroundings do not occur, and the temperature changes slowly. Therefore, the timing of ending the operation of the circulation pump 4 can be accurately determined by detecting the temperature of the refractory material 5. Can be detected.

1 Heating medium boiler
2 Heat use part
3 Heat transfer oil heating tube
4 Circulation pump
5 Refractory materials
6 Inverter device
7 Refractory temperature detector
8 Operation control device
9 Heat medium oil temperature detector
10 Number control device
11 Heat medium oil collecting pipe 12 Heat medium oil distribution pipe 13 Boiler outlet pipe 14 Boiler inlet pipe

Claims (1)

A side wall is formed by a coiled heat transfer oil heating tube with a space in the center, and the upper and lower ends have a cylindrical combustion chamber that is insulated with a refractory material, and the heated heat transfer oil is supplied to the heat use section. In the heat medium boiler, the circulation pump is provided in the heat medium oil pipe connecting the heat use part and the heat medium boiler to circulate the heat medium oil, and the rotation speed of the circulation pump is changed. When the heat pump oil cooling operation is performed during the heat medium oil cooling operation after the heat medium boiler operation is stopped, the heat medium changing device and the refractory material temperature detecting device for detecting the refractory material temperature of the heat medium boiler are provided. A heating medium boiler, characterized in that control for lowering the number of revolutions of the circulation pump than during operation of the boiler is performed until the temperature of the refractory material detected by the refractory material temperature detection device decreases to a set value .

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