JPS6044757A - Constant pressure and constant temperature apparatus in hot water supply system - Google Patents

Abstract

PURPOSE:To make it possible to supply hot water stably at a constant temperature and constant pressure such as hot water from a hot spring, water heated by subterranean heat, and industrial hot waste water, by circulating a prescribed amount of hot water and automatically controlling the flow rate control valve of a return pipe to keep the pressure in the pipe constant at all times. CONSTITUTION:In a system comprising a hot water storage tank 1, a circulating pump 3 and a hot water circulating pipeline 5 for circulating hot water to be supplied, a pipeline 5 is divided near to a hot water discharge outlet 6 of the circulating pump 3 into a return pipe 7 and a pipeline for supplying and circulating the hot water, motor- driven flow rate control valves 8, 12 are provided respectively near to an end section 10 of the hot water circulating pipeline 5 to the hot water storage tank 1 and near to the return pipe 7, a pressure detecting apparatus 9 is provided for detecting the pressure in said pipeline for supplying and circulating the hot water, and to make constant the value of the flowmeter 11 located near the end section 10 of the circulating pipe 5 and the pressure in the pipe detected by a pressure detector 9, the motor-driven flow rate control valves 8, 12 are controlled by a control mechanism 13, so that a stabilized quantity of hot water can be supplied to a user.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant pressure and temperature device in a hot water supply system. Regardless of the conditions of use, such as the difference in usage between peak load (peak load) when the daily amount of hot water used is at its maximum and other non-beak load times, the temperature is always constant. A constant-pressure constant-temperature device for a hot water supply system that has a mechanism that can stably supply hot water at a constant pressure, and that also allows the diameter of the hot water circulation pipeline to be reduced to reduce construction costs. It is related to.

2- As shown in Figure 1, the amount of hot water used on day - varies depending on the time, and in particular, the amount used around 6:00 pm during peak load hours is much higher than during non-peak load times. It jumps up by the difference in . For this reason, in the conventional hot water supply system, the flow rate in the hot water circulation pipe is set to 2 to 2.5 times the amount used at peak load to overcome the load at peak load and maintain temperature constant. I'm trying. Therefore, the diameter of the pipeline inevitably increases, and the power of the circulation pump must accordingly increase. Therefore, this naturally increases the construction cost, and there is also the disadvantage that the pressure within the pipeline is not always constant.

Therefore, this invention was created in view of the above-mentioned drawbacks, etc., and its gist is a hot water storage tank, a circulation pump that sends out hot water from the hot water storage tank, and a supply of hot water to the place where it is used. In a hot water supply system consisting of a hot water circulation pipe that circulates a predetermined amount of hot water and flows it back into the hot water tank in order to maintain a constant temperature of the hot water supplied, the hot water discharge port of the circulation pump Nearby, the pipe is branched into a pipe for supply and circulation of hot water and a return pipe for returning hot water directly to the hot water storage tank, and the inlet side of the pipe for supply circulation is connected to the internal pressure of the hot water. A pressure detection device is installed to detect the hot water, and a flow rate adjustment valve is installed in the turn pipe mentioned above.Furthermore, near the end of the circulation pipe to the hot water storage tank in the pipe for supply circulation, a flow rate adjustment valve is installed in the turn pipe. A flow meter and a flow rate adjustment valve are installed to measure the flow rate of hot water, and regardless of the amount of hot water used, the value of the flow meter near the end of the circulation pipe is necessary to maintain the temperature constant. Automatically controls a flow rate regulating valve near the end of the circulation pipe to maintain a flow rate of only a predetermined amount of hot water, and always maintains the pressure inside the pipe detected by the pressure detection device at a constant pressure. Control tl that automatically controls the flow rate adjustment valve of the return pipe as much as possible
This is due to the provision of the llffi structure.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

That is, the reference numeral 1 shown in the figure is a hot water storage tank,
Hot water such as hot spring water, geothermal water, industrial heat waste water, etc. is stored through a source hot water inflow pipe 2 from the outside.

A circulation pump 3 that sends out hot water from the hot water storage tank 1 is connected to the hot water storage tank 1, and the circulation pump 3 has a hot water circulation pipe 5 that can supply the hot water sent out to various places 4 where it is used. connected. This hot water circulation pipe 5 is used to circulate the flow rate near the discharge port 6 of the circulation pump 3 during beak load 16 and to keep the hot water supply temperature constant. (A + α), A is consumed in the hot water circulation pipe 5 and the flow rate at the flow end 10 of the hot water circulation pipe 5 is α. It is a combination of the pipe diameter determined by calorific value calculation and the thickness of the insulation material for heat retention. However, A>>
It is α.

However, the hot water circulation pipe 5 formed by the pipe diameter and insulation material thickness determined by the above calculation is subject to uncertainties such as the internal roughness coefficient, the characteristics of the circulation pump 3, and changes in the used ff1A at beak load. The pressure within the hot water circulation pipe 5 is not necessarily constant depending on the factors, and the flow rate α at the flow end portion 10 of the hot water circulation pipe 5 is not always constant.

Therefore, a branch pipe is formed near the discharge port 6 of the circulation pump 3, and one is used as the hot water circulation pipe 5 for supplying hot water, and the return pipe 7 is used to directly return hot water to the hot water storage tank 1. . A pressure detection device 9 for detecting the pressure inside the pipe is installed in the former hot water circulation pipe 5, and a pressure detection device 9 is installed in the latter return pipe 7.
In order to keep the internal pressure of the hot water circulation pipe 5 constant at all times,
An electric flow rate control valve 8 is provided to adjust the flow rate in the return pipe 7.

In addition, near the end portion 10 of the hot water circulation pipe 5, which is the part where the hot water returns to the storage 4i\J1, there is a A flow meter 11 and an electric flow rate adjustment valve 12 are provided to control the flow rate so that the flow rate is α.

In order to adjust the flow rate to keep the internal pressure of the hot water circulation pipe 5 constant regardless of the amount of hot water used and to make the supply temperature constant, a flow end portion 10 of the hot water circulation pipe 5 is provided. A control mechanism 13 capable of automatic control such as a computer is provided to automatically control the flow rate adjustment to fix the flow rate at α.

Next, to explain the operation, hot water stored in the hot water storage tank 1 is sent out by the circulation pump 3. This hot water is then supplied to the hot water usage locations 4 located at various locations through the hot water circulation pipe 5 as shown by the arrow lines in Fig. 2, and the hot water that remains after being used is Furthermore, hot water circulation pipe 5
The hot water flows through the flux section 10 of the circulation pipe 5 into the hot water storage tank 1 again, but at that time, the amount of hot water remaining after being used and returning to the hot water storage tank 1 is greater than the predetermined amount determined by the flow meter 11. If it is determined that this is the case, the control mechanism 13 automatically sends a signal to close the electric flow rate adjustment valve 12 and adjusts the flow rate to a predetermined level, and conversely, the amount of return is less than the predetermined amount. In this case, the control mechanism 13 automatically sends a signal to open the electric flow rate regulating valve 12 in the same manner as described above. Therefore, the amount of hot water returned to the hot water storage tank 1 is always constant, and as a result, the supply temperature of hot water is constant.

However, with only the above-mentioned control, although the flow rate of hot water returning to the hot water storage tank 1 is constant, the pressure inside the hot water circulation pipe 5 fluctuates by J: depending on the amount of hot water used.

Therefore, the pressure inside the pipe is measured by the pressure detection device 9 installed in the hot water circulation pipe 5 near the discharge port 6 of the circulation pump 3, and if the pressure inside the pipe becomes larger than a predetermined value,
The control mechanism 13 automatically sends a signal to open the electric flow rate adjustment valve 8 of the return pipe 7, and a part of the hot water discharged by the circulation pump 3 is sent directly to the hot water tank 1 to reduce and adjust the pressure inside the pipe. be. On the other hand, when the pressure inside the pipe becomes smaller than a predetermined value, the control 'll1114R13 automatically sends a signal to close the electric flow rate adjustment valve 8, and the discharge pressure of the circulation pump 3 remains unchanged for hot water circulation. Conduit 5
The pressure inside the pipe is always kept constant at a predetermined value.

In the figure, 1/I is a flow rate word that measures the flow of hot water near the discharge port 6, and 15 is a wiring from the control mechanism 13 to the flow meter 11, pressure detection device 9, and each electric flow rate adjustment valve 8.12. It is a signal cable.

Since this invention is configured as described above, the hot water storage tank 1
The hot water sent out is always supplied to the place 4 where hot water is used at a constant pressure, and the supply temperature can also be kept constant, so a stable amount of heat can be supplied to the users, and furthermore, hot water circulation can be improved. The diameter of the conduit 5 can also be made to produce results consistent with wood grain and calorific value calculations, and therefore the diameter can be made smaller, reducing construction costs and reducing emissions from the conduit. It is possible to minimize the amount of heat.

As explained above, the present invention provides a hot water supply system including a hot water storage tank 1, a circulation pump 3, and a hot water circulation pipe 5 that circulates and supplies hot water. Avoid branching the pipe line 5 into a return pipe 7 and a pipe line for supplying and circulating hot water near the discharge port 6; original end part 10
Electric flow rate adjustment valves 8 and 12 are provided in the vicinity, and a flow meter 11 is also provided in the vicinity of the bulk part 10 of this circulation pipe 5, and a pipe for supplying and circulating hot water among the branched pipes is provided. A pressure detection device 9 is installed in the passage, and a pressure detection device 9 is installed in order to keep the value of the flow meter 11 near the bulk end portion 10 of the circulation pipe 5 constant regardless of the amount of hot water used. By controlling each of the electric flow rate regulating valves 8 and 12 by the control mechanism 13 in order to keep the pressure inside the pipe detected by the device 9 constant, a stable amount of heat from hot water can be supplied to the user, and the diameter of the pipe can be adjusted. By making it as thin as possible, it is possible to reduce construction costs and power costs, and it has excellent effects such as being able to minimize heat loss from the hot water circulation pipe 5. be.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the usage of hot water per hour in one day, and FIG. 2 is an overall schematic piping system diagram showing one embodiment of the present invention. 1... Hot water storage tank, 2... Source hot water inflow piping, 3... Circulation pump, 4... Place of use, 5...・Hot water circulation pipe, 6...Discharge port, 7...Return pipe, 8...Electric flow rate adjustment valve, 9...Pressure detection device, 10...
...Flux section, 11...Flowmeter, 12...
...Electric flow rate adjustment 10- Valve adjustment, 13... Control mechanism, 16... At beak load, 17... At no beak load. Patent applicant Noboru Hosoya 11-

Claims (1)

[Scope of Claims] 1. A hot water storage tank, a circulation pump that sends out hot water from the hot water storage tank, and a predetermined amount of hot water that supplies the hot water to a place where it is used and keeps the temperature of the hot water constant. In a hot water supply system consisting of a hot water circulation pipe for circulating hot water and flowing it back into the hot water storage tank, the pipe is connected to a pipe for supplying and circulating hot water near the hot water outlet of the circulation pump. A pressure detection device is installed on the inlet side of the pipeline for supply circulation to detect the pressure inside the hot water pipe, and the return pipe has a flow rate. A regulating valve is installed, and a flow ff1id and a flow regulating valve are installed near the main part of the circulation pipeline to the hot water storage tank in the supply circulation pipeline to measure the flow rate of the hot water that has been circulated. Regardless of the amount used, the flow rate of the circulation pipe should be adjusted so that the value of the flow meter near the large part of the flow of the circulation pipe is set to only the flow rate of a predetermined amount of hot water necessary to maintain the temperature constant. A controller groove is provided to automatically control the flow rate adjustment valve in the return pipe in order to automatically control the flow rate adjustment valve in the vicinity of the return pipe and to always keep the pressure inside the pipe detected by the pressure detection device at a constant pressure. A constant pressure constant temperature device for a hot water supply system characterized by the following.