RU2345953C1 - Deaeration tower - Google Patents

Abstract

FIELD: engines and pumps, chemistry.

SUBSTANCE: deaeration tower comprises an accumulating tank with a branch pipe intended for sucking off non-condensing gases and a column fitted above the said tower and representing water-jet ejector with water-feed device made up of a set centrifugal jets fitted regularly over the column cross and a steam-feed circular manifold connected to the aforesaid column by radial crossbars. A taper-like entrainment separator is arranged on the column outlet. Note that the column is divided by vertical partitions into sections consecutively interconnected along the steam-gas path by the separator. Mind that the column consists of at least two units connected in parallel along the steam and discharged gas paths. Each of the centrifugal jets incorporates housing with a chamber wherein an auger is press-fitted. Note also here that the housing bottom has a throttling orifice while the housing top part accommodates a union provided with a cylindrical bore, a diffuser and a gasket. The said auger inner part has a threaded hole, the direction of the thread of the said hole being aligned with the auger outer thread direction. Note also that a mixing taper chamber is fitted above the throttling orifice to form a total finely dispersed swirling flow.

EFFECT: higher efficiency and quality.

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Description

The invention relates to the field of thermal deaeration of a liquid, mainly feed water of a steam turbine unit, and can be used in thermal and vacuum deaeration plants, as well as in strippers of gaseous products dissolved in process liquids.

The closest technical solution to the claimed facility is a deaerator according to USSR copyright certificate No. 553215, class. С02В 1/10, 1975, containing a storage tank with a nozzle for suction of non-condensable gases and a column mounted above it in the form of a water-jet ejector with a water supply device made in the form of a centrifugal nozzle column evenly spaced along the section and a steam supply manifold made annular and connected to column with radial jumpers, and in the tank at the outlet of the column a cone-shaped drop collector is installed.

A disadvantage of the known device is the low hydraulic resistance and low quality of deaeration associated with coarse atomization of the liquid, as well as low productivity.

EFFECT: increased productivity due to fine atomization of liquid.

This is achieved by the fact that in a deaerator containing a storage tank with a nozzle for suction of non-condensable gases and a column mounted above it in the form of a water-jet ejector with a water supply device made in the form of a centrifugal nozzle column evenly spaced along the section and a steam supply collector made annular and connected to column with radial jumpers, and in the tank at the outlet of the column a cone-shaped drop eliminator is installed, the column is divided into vertical sections by partitions, connected in series interconnected along the gas-vapor path through a separation device, the column being made of at least two blocks connected in parallel with steam and exhaust gas, and each of the centrifugal nozzles contains a housing with a chamber into which a screw is pressed into, and in the bottom of the housing throttle hole, and in the upper part there is a fitting with a cylindrical hole, a diffuser and a gasket, and a screw hole is made inside the screw, the direction of which coincides with the direction of the external screw dressing the screw and over a throttle opening arranged conical mixing chamber to form a particulate aggregate of the rotating flow.

1 shows a deaerator; figure 2 - diagram of a centrifugal nozzle.

The deaerator contains a column 1, mounted above the storage tank 2, divided by vertical partitions 3 into three sections 4, 5, 6. An annular steam supply manifold 7 is connected to the column by radial bridges 8. In each section, centrifugal nozzles are located 9. The sections are interconnected via a separation the device formed in this case by partitions 3. For the drainage of water from column 1 to the tank 2, nozzles 10 are used, and for the removal of non-condensable gases - pipe 11. The system for supplying water to the nozzles is made in two stages and is supplied with and 12, 13 valves.

The centrifugal nozzle (figure 2) consists of a housing 14 with a cover 16, inside which is located the screw 15. The outer surface of the screw 15 is a helical groove with right (or left) thread. Inside the screw 15, a hole 24 is made with a left (or right) screw thread. At the bottom of the housing 14, a throttle hole 22 is made, the axis of which coincides with the axis of the hole 24 in the screw 15. Between the lower end of the screw 15 and the slice of the throttle hole 22 there is a mixing chamber consisting of a cylindrical 21 and a conical 23 parts.

The screw 15 is rigidly connected to the T-shaped throttle washer 18, in the end cylindrical part 17 of which at least three throttle openings 19 are made, and in the rigidly connected axial cylindrical part there is an axial throttle hole 26. The hydraulic resistance of the throttle openings 19 and 26 is selected depending on the properties of the sprayed liquid and the desired degree of spray.

The supply of the solution (liquid) is carried out through the hole in the fitting 20, mounted in the upper part of the housing 14 through the end cylindrical part 17 of the T-shaped throttle washer 18.

Deaerator works as follows.

Water is supplied to the nozzles of section 9, heating steam from the annular collector 7 also enters here. Due to the ejection effect created by the sprayed water torches, the steam is entrained in the cavity of the torch and quickly heats the water to boiling point. In the area between the partitions 3 of section 4, a liquid flows out of the two-phase flow, which collects in the lower part of the column and flows through the nozzles 10 into the storage tank 2, and the gas-vapor mixture is sucked by the nozzle nozzles of section 5, then after separation the gas-vapor mixture of section 5 enters section 6 where the final condensation of the steam takes place, and the gases are released into the atmosphere through the pipe 11.

A centrifugal nozzle for spraying liquids works as follows.

The fluid is fed through the hole in the nozzle 20 and through the T-shaped throttle washer 18 enters simultaneously in two directions: firstly, into the screw outer cavity 25 of the screw 15 through the throttle holes 19 and, secondly, into the hole 24 with a screw thread through the throttle hole 26. A rotating fluid stream from the screw outer cavity 25 of the screw 15 enters the mixing chamber, consisting of a cylindrical 21 and a conical 23 parts. On the other hand, liquid enters the mixing chamber from the screwed hole 24, rotating in the direction opposite to the external flow going through the screw 15, or making a passing (identical) rotation. In the interaction of rotating flows in the mixing chamber, additional droplets of liquid are crushed due to their collision in associated or opposite rotating liquid flows (external and internal). The total finely dispersed rotating stream exits through the throttle hole 22, and the direction of its rotation is determined by the hydraulic resistance of the external 25 or internal screw cavities 24 of the screw 15, respectively.

The nozzle screw 15 can be made of solid materials: tungsten carbide, ruby, sapphire. With an average diameter of the throttle bore 22, which is in the range of 2.5 ... 3.5 mm and a fluid pressure of 6 ... 9 MPa, atomization of 400 to 1000 kg / h of fluid is ensured. The nozzle is easy to manufacture and maintain.

Centrifugal nozzles 9 with a uniform distribution of liquid in the flare are installed in such a way that the flares reliably overlap the annular section of the irrigated zone at a certain distance from the nozzles with a minimum of water falling onto the walls. The diameter of the nozzle orifice 22 of the nozzles of section 5 (the second stage of deaeration) is much smaller than section 4 (the first stage of deaeration), and section 6 (the third stage of deaeration) is smaller than in section 5, and therefore the spray during the transition from stage to stage becomes thinner, but since the steam consumption decreases sharply, the latter does not actually affect the drop-nose.

For repair and maintenance of the column, as well as the replacement of individual nozzles without stopping the entire deaerator, the column can be made of at least two blocks connected in parallel with steam and exhaust gas.

When changing the flow rates of water, steam and the content of deaerated gases, it is necessary to change the flow rate of the vapor after the first stage. A two-stage water supply system with valves 12, 13 allows you to maintain the flow rate of the vapor after the first stage (section 4) at an optimal level. In normal operation, both valves are open. If it is necessary to reduce the flow rate of the vapor, the valve 12 closes, and the pressure in the sections 5, 6 drops. If it is necessary to increase this flow rate, valve 13 closes, and the pressure on the nozzles of the last stages will be maximum.

The proposed deaerator has an enlarged surface and contact time, it provides cooling of the vapor, since in each subsequent stage the vapor of the previous one is cooled.

Claims (1)

A deaerator containing a storage tank with a nozzle for the extraction of non-condensable gases and a column mounted above it in the form of a water-jet ejector with a water supply device made in the form of a centrifugal nozzle column evenly spaced along the section and a steam supply collector made circular and connected to the column by radial jumpers, and in a cone-shaped drop collector is installed at the outlet of the column, characterized in that the column is divided by vertical partitions into sections connected in series between each other along the gas-vapor path through a separation device, and the column is made of at least two blocks connected in parallel with steam and exhaust gas, and each of the centrifugal nozzles contains a housing with a chamber into which the screw is pressed into, and a throttle hole is made in the bottom of the housing, and in the upper part there is a fitting with a cylindrical hole, a diffuser and a gasket, and a screw hole is made inside the screw, the direction of which coincides with the direction of the external screw thread eka, and above the throttle hole there is a conical mixing chamber for the formation of a total finely dispersed rotating stream.

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