JPS5895102A - Deaerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a deaerator, in particular oxygen dissolved in water supply,
The present invention relates to a deaerator suitable for removing gases such as carbon dioxide gas.

Conventional methods for removing dissolved oxygen, carbon dioxide, etc. from boiler feedwater include using vacuum means such as an ejector to lower the pressure inside the deaerator to the saturation pressure of the feedwater, lowering the solubility of the gas, and degassing. There are two methods: one method is to supply water vapor into a deaerator, and the other is to raise the temperature of the feed water to the saturation temperature under the pressure inside the deaerator to lower the solubility of the gas and degas it. In the former method, in order to ensure deaeration performance, it is necessary to reduce the pressure inside the deaerator to the pressure at the saturation temperature of the feed water, but the pressure inside the deaerator must be reduced to accommodate fluctuations in the feed water temperature, etc. It was difficult to control the pressure to a certain level, and sufficient degassing performance was not maintained, and there were also drawbacks to the stone, which self-evaporated excessively in the vessel and released steam outside the system. In addition, in this case, since the temperature of the water supply at the deaerator outlet is low, if a economizer is installed when the gas contains low-temperature corrosive components such as sulfur oxides and carbon dioxide, the outer surface of the economizer heat transfer tube will corrode. There is also a drawback. In the latter method, since heating steam is required, the boiler equipment needs to add the heating steam amount to the process air supply amount to obtain a 9' capacity, which increases the equipment cost.

The purpose of the present invention is to remove dissolved oxygen and carbon dioxide from the water supply without deteriorating the deaeration performance due to changes in the water supply temperature or without receiving water vapor from the outside. The aim is to provide air-conditioning equipment.

The present invention focuses on the thermal energy possessed by the blow water extracted from the steam drum of the boiler, and uses this thermal energy to heat the gas-dissolved water supplied to the boiler feedwater deaerator with the generated steam. , which is designed to remove air.

Embodiments of the present invention will be described below based on the drawings.

Fig. 1 is a system diagram of an apparatus showing an example of the present invention, in which 1 is a feed water tank, 2 is a feed water heater, 3 is a deaerator, 4 is a combustion chamber, 5 is a steam drum, and 7 is a flash Showing the tank.

The gas-dissolved water in the water supply period 1 is heated in the feed water heater 2 and then supplied to the deaerator 3. After the degassed water is heated through four preheating sections in the combustion chamber 4, it is introduced into the steam drum 5, and then steam is generated in the evaporation section 4B and discharged to the steam drum 5 as a mixture of air and water temperature. The saturated steam separated in the steam drum 5 is led to the superheating section 4C, and is converted into Pf as superheated steam.
Supplied to rlN equipment and equipment.

Here, the blow water from the steam drum 5 is introduced into a flash tank 7 via a continuous blow pipe 6. The interior of the steam drum 5 is under high pressure conditions, and the interior of the flash tank 7 is at a lower pressure (for example, about 4d) than the internal pressure of the steam drum, so the blown water turns into steam in the flash tank. This steam is supplied to the deaerator 3 via the pipe 8.

In the deaerator 3, the gas-dissolved water sprayed from the spray nozzle 9 provided at the upper part of the deaerator 3 is supplied to the deaerator 3, heated by the vapor, and raised to the saturation temperature at the deaerator internal pressure. do. In this process, the solubility of the gas in the gas-dissolved water decreases and it is degassed, and the degassed gas is released outside the vessel.
Degassed water is introduced into the preheating section 4A as described above.

The pressure in the flash tank 7 is controlled by the amount of blow water supplied to the flash tank by the pressure control pulp 10, and the level of blow water in the flash tank 7 is:
This is done by controlling the flow rate of the blow water using the flow rate control pulp 11.

Gas-dissolved water supplied from the water tank 1 is heated by the heat retained in the blow water introduced into the water supply heater 2 from the lower part of the flash tank 7 . Blow water that has passed through the feed water heater 2 is led to a blow tank 12. In addition, in the figure, 13 indicates a burner.

In the present invention, a part of the water supply line leading from the feed water heater to the deaerator is branched, a heat exchanger is provided in this branch line, and in this heat exchanger, the gas/dissolved water heated by the feed water heater is It is also possible that the water is indirectly heat exchanged with the blow water and the steam generated by being heated by the heat retained in the blow water is introduced into the deaerator.

According to this embodiment, the steam introduced into the deaerator is generated by indirect heat exchange with blow water, and has the effect of preventing the occurrence of carryover.

As described above, according to the present invention, the internal pressure of the deaerator is kept constant, so unlike vacuum deaerators, the deaeration performance does not deteriorate due to changes in the feed water temperature, and There is no need to supply water vapor.

It is also possible to use the steam generated by the Gay 2 main unit as the steam supplied to the deaerator, but in this case, low-energy steam would be enough, but high-energy steam would be used as the deaerator steam, and the energy would be low. However, since the present invention utilizes the heat retained in the blow water of the steam drum, the thermal energy can be used effectively.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an apparatus showing an example of the present invention. 1... Water supply tank, 2... Water supply heater, 3.
... Deaerator, 4... Combustion chamber, 5... Steam drum, 7... Flash tank, 9... Spray nozzle, 12... Blow tank 13... Burner. Agent Tatsuyuki Unuma (and 2 others)

Claims (1)

[Claims] (1) It is configured to heat and degas the gas-dissolved water supplied to the boiler feedwater deaerator with the steam generated by utilizing the retained heat of the blow water extracted from the steam drum of the boiler. A degassing device characterized by: