JPH10103601A - Steam generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporator to improve efficiency through prevention of adhesion of scales due to water supply, in the evaporator employing a spiral type heat-exchanger. SOLUTION: An evaporator 1 employing a spiral type heatexchanger 5 and a water supply tank 2 are arranged in juxtaposition, the two devices are communicated at respective lower parts with each other through a coupling pipe 3 and connected together at respective upper parts through a coupling pipe 4. Heat-exchange with water supplied from a feed water valve 9 to one flow passage through the coupling pipe 3 is effected by steam entering the other flow passage of the heat-exchanger 5 from a steam introduction part 6 through a steam valve 8. Generated secondary steam is outputted from a steam output part 7 above the water supply tank 2 through the coupling pipe 4. The steam valve 8, the water supply valve 9, and a drain valve 10 arranged at the bottom of a device are controlled by a control part 11, a total amount of water retained in a device is periodically forcibly drained and substituted for fresh supply water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam generator, and more particularly, to a device for discharging the entire amount of retained water so that scale does not adhere to a spiral heat exchanger.

[0002]

2. Description of the Related Art Conventionally, an evaporator and a water supply tank are provided side by side as a steam generator, and a communication pipe is provided below both of them, and steam generated by the evaporator is supplied to an upper part of the water supply tank through an upper connection pipe. The structure for taking out from the steam take-out part is well known. In the drawings, reference numeral 1 denotes an evaporator, 2 denotes a water supply tank, both of which are provided side by side, are connected by a connecting pipe 3 at a lower part, and are connected by a connecting pipe 4 at an upper part. Evaporator 1
Is provided with a spiral heat exchanger 5 and a primary steam inlet 6
Provided to be discharged through one flow path of the heat exchanger 5,
On the other hand, water supplied from the water supply tank 2 is supplied to the evaporator 1 in the flow path.
The generated secondary steam passes through the connecting pipe 4 and is taken out from a steam take-out part 7 above the water supply tank 2.

[0003]

The water supplied to the other flow path of the spiral heat exchanger is controlled at the liquid level in the middle of the heat exchanger. Reheat is performed on the heat transfer surface at the top of the heat exchanger, and high-quality steam with little moisture can be obtained. However, since the liquid surface is composed of a narrow flow path, the supplied water is concentrated by evaporation, and the scale easily adheres to the heat transfer surface, which lowers the heat exchange efficiency and the danger of corrosion due to the attached scale. There were problems such as the occurrence of cracks.

Attempts have been made to intermittently forcibly drain the water in the evaporator in an attempt to solve this difficulty. However, when the amount of discharged water is small, the liquid level in the flow path in the heat exchanger is the same. Simply move the water up and down, it does not mix well with the new water supply, and the concentration progresses, leaving the scale adhered to the heat transfer surface. And costs are required.

An object of the present invention is to solve the above-mentioned problems and to provide an apparatus capable of periodically discharging the entire amount of water retained in the apparatus and replacing it with fresh water.

[0006]

In order to achieve the above object, in the first invention, an evaporator using a spiral heat exchanger and a water supply tank are provided side by side, and a connecting pipe connecting the two at a lower portion is provided. A connecting pipe for connecting the two at the upper part is provided, and a primary steam introduction part as a feed water heating source is provided in the evaporator via a steam valve, and steam is supplied to one flow path of the heat exchanger to provide an external part. To the other flow path of the heat exchanger,
A steam generator that fills an evaporator with water supplied from a water supply valve to a water supply tank through a lower connecting pipe and exchanges heat, and takes out generated secondary steam from a steam take-out unit provided at an upper part of the water supply tank. In the above, a steam generator was provided in which a control unit was provided so that the entire amount of water held in the apparatus was closed by closing the steam valve and the water supply valve, and a drain valve provided at the bottom of the apparatus was opened to periodically forcibly drain water.

According to a second aspect of the present invention, there is provided a steam generator in which the liquid level in a heat exchanger of an evaporator is controlled by a liquid level gauge attached to a water supply tank, and the total amount of retained water can be checked. In the third invention, the steam generator is provided such that a drain valve is opened by a timer or other control unit so as to periodically drain the entire amount. (Function) In the first invention, the steam valve of the steam introduction section for supplying the primary steam, the water supply valve for supplying the water supply tank, and the drain valve at the bottom of the apparatus are controlled as a whole, and the entire amount in the apparatus is periodically forced. Since the control unit is provided so as to discharge the water, the whole amount can be replaced with fresh water instead of the stepwise discharge as in the conventional example, and the adhesion of scale can be prevented.

In the second invention, the liquid level gauge provided in the water supply tank allows the liquid level in the heat exchanger to be controlled at the time of operation, and the liquid level gauge is provided so that the discharge of the retained water in the apparatus can be confirmed. , Control was ensured and scale adhesion was prevented. According to the third aspect of the present invention, the total amount of the retained water is periodically drained by timer control, or automatic control by the control unit is enabled.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, an evaporator and a water supply tank are provided side by side, and both are communicated with a lower connecting pipe, and secondary steam generated from the upper connecting pipe is taken out of the upper steam of the water supply tank. From the department. The evaporator has a spiral heat exchanger, has a primary steam inlet as a feedwater heating source, supplies steam to one flow path of the heat exchanger through a steam valve, and has a feedwater tank in the other flow path. The water is supplied through the water supply valve so as to fill the evaporator and is evaporated by the heat exchanger.

In the present invention, a drain valve is provided so as to control the level of liquid supplied to the evaporator via the steam valve and the water supply valve, and to periodically forcibly discharge all the water retained in the apparatus. The discharge is performed by using a control unit, for example, a timer. Since the entire amount is discharged, it is possible to prevent concentrated water from remaining in a narrow flow path such as a heat exchanger, and to generate more efficient steam by generating secondary steam from new replaced water supply. became.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference numeral 1 denotes an evaporator, 2 denotes a water supply tank, and 3 denotes a connecting pipe. The two are connected below the evaporator 1 and the water supply tank 2. Reference numeral 4 denotes an upper connecting pipe which sends out steam generated in the evaporator 1 to the water supply tank 2. Reference numeral 5 denotes a spiral heat exchanger whose feed water is a primary steam inlet 6 as a heat source.
The steam is introduced into the heat exchanger, enters the one flow path of the heat exchanger, and is discharged. Reference numeral 7 denotes a steam extracting section for extracting the steam generated in the evaporator 1 from above the water supply tank 2 via the connecting pipe 4. 8 is a steam valve, 9 is a water supply valve, 1
0 is a drain valve. Steam valve 8, water supply valve 9, and drain valve 10
Are respectively controlled by the control unit 11.

Reference numerals 12 and 13 denote level gauges attached to the water supply tank 2. The level gauge 12 controls the liquid level in the heat exchanger connected to the connecting pipe 3 so that the generated steam can be managed. The liquid level gauge 13 can check and control whether or not the entire amount in the apparatus has been discharged. The liquid level gauge is 2
Instead of using individual pieces, long ones can be used for both purposes.

The control unit 11 can control and manage the steam valve 8 and the water supply valve 9 to be closed and the drain valve 10 to be opened so that the entire amount of the retained water is drained at regular intervals using a timer, for example. Not only the timer but also computer control can be used to periodically repeat the entire drainage, re-watering, and evaporator operation. As described above, the case where the water supply liquid surface is located in the middle of the heat transfer surface has been described. However, even when the water supply liquid surface is located above the heat transfer surface, the total drainage is effective.

[0014]

According to the first invention of the present invention, when evaporation and supply of water supplied in a narrow flow path such as a spiral heat exchanger are repeated, the scale is attached by periodic forced drainage of the entire amount. Can be prevented, and the heat transfer efficiency can always be kept at the best. According to the second invention, the liquid level in the evaporator can be easily controlled by the liquid level gauge and the total drainage can be easily confirmed.

[0015] In the third aspect of the present invention, it is possible to automatically manage the periodic discharge of the total amount of water held in the apparatus and fresh water supply by the control unit.

[Brief description of the drawings]

FIG. 1 is a system diagram showing the entire apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Evaporator 2 Feedwater tank 3, 4 Connecting pipe 5 Spiral heat exchanger 6 Steam introduction part 7 Steam extraction part 8 Steam valve 9 Feedwater valve 10 Drainage valve 11 Control part 12, 13 Level gauge

Claims (3)

[Claims] 1. An evaporator using a spiral heat exchanger and a water supply tank are provided side by side, a connecting pipe connecting the two at a lower part is provided, and a connecting pipe connecting the two at an upper part is provided.
The evaporator is provided with a primary steam introduction unit as a feed water heating source via a steam valve, supplies steam to one flow path of the heat exchanger and discharges it to the outside, and the other flow path of the heat exchanger has Steam generated by filling the water supplied from the water supply valve to the water supply tank to the evaporator through the lower connecting pipe and exchanging heat, and taking out the generated secondary steam from the steam outlet provided at the upper part of the water supply tank. A steam generator, wherein the steam generator and the water supply valve are closed with a total amount of water held in the device, and a control unit is provided so as to open a drain valve provided at the bottom of the device to periodically forcibly drain water. . 2. The steam generator according to claim 1, wherein the liquid level in the heat exchanger of the evaporator is controlled by a liquid level gauge attached to the water supply tank, and the total amount of the retained water can be checked. 3. The steam generator according to claim 1, wherein a drain valve is opened by a timer or other control unit so as to periodically discharge the whole amount.