The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the present invention provides an apparatus for removing ash from pressure parts of a Radiant Synthesis Gas Cooler (RSC). The embodiments in accordance with the present invention may include a rapper actuator, a striker pin, a striker target, and wear plates.
The rapper actuator 12 attaches to a flange 18 that is mounted on an outside surface of a wall 20 of a pressure vessel 22. The pressure vessel 22 is operated at pressures above atmospheric pressure and the environment inside the pressure vessel is in general corrosive. There are seals and inert gas purge to allow the penetration of the striker pin 14 through the pressure vessel wall 20 and without leakage of syngas to the atmosphere. Inside the pressure vessel is a tube and membrane construction pressure part assembly, sometimes called a tube cage assembly 24 that is typically round, but can be multiple sided. The tube cage assembly 24 is completely seal welded to contain the syngas. There is a space between the pressure vessel wall 20 and the tube cage assembly 24 called an annulus 26. The annulus 26 is continually purged with an inert gas to assure syngas does not remain in the annulus 26 and cause corrosion of tubes 28 forming the tube cage assembly 24 or the wall 20 of the pressure vessel 22.
On the inside of the tube cage assembly 24 are other pressure part assemblies 30 that absorb heat to produce steam. The pressure part assemblies 30 are sometimes called platens, division walls or wing walls. These internal pressure part assemblies 30 have ash depositing on the surface that reduce heat transfer and steam production. To maintain the required or expected steam production, the internal pressure part assemblies 30 need to be cleaned. Rapping energy induces a vibration in the pressure part assemblies 30 that induces shedding of the ash deposits. The highest rapping energy is transmitted to the internal pressure part assemblies 30 when there is direct contact between the rapper actuator 12 and the internal pressure part assemblies 30 and when the striker pin 14 and striker target assembly 16 are free to move.
One embodiment involves the striker target assembly 16, which includes at least one striker target plate 32. If two striker target plates 32 are used, they are located on opposite sides of a tube. There are slots 34 in the tube cage assembly 24 so that the striker target plate 32 can pass from the annulus 26 to the internal pressure part assemblies 30. The slots 34 are created by leaving a portion of a membrane 40 surrounding the tube cage assembly 24 off the assembly. The striker target plate 32 is sized to provide small gaps around the plate periphery, which minimize the amount of inert purge gas leakage from the annulus and allows for free movement of the target. The close fit between the striker target plate 32 and the tube cage assembly 24 maintains alignment between the striker pin 14 and the striker target assembly 16.
The internal pressure part assembly 30, the tube cage assembly 24, and the pressure vessel 22 operate at different temperatures. The thermal expansion of each component is different. Additionally, the internal pressure part assembly 30 can bow due to differential expansions. The internal pressure part assembly 30 must be oriented inline with the striker pin 14 and the striker target assembly 16. The striker target assembly 16 must also be in alignment with the internal pressure part assembly 30. The alignment is provided with tubes 36 from the pressure part assembly 30 which are bent around the striker target assembly 16. Attached to the tubes 36 are wear plates 38 that protect the tubes 36 and provide the alignment of the striker target assembly 16 and the internal pressure part assembly 30.
Alignment of the striker target assembly 16 to the internal pressure parts assembly 30 is provided while allowing free movement between the internal pressure part assembly 30, tube cage assembly 24, and the striker target assembly 16. Additionally, free movement of the striker target assembly 16 within the tube cage assembly 24 is provided, which maximizes the transmitted energy to the internal pressure part assembly 30. The gap between the annulus 26 and an internal side of the tube cage assembly 24 is minimized, which, in turn, minimizes the amount of inert gas leakage.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
Number | Date | Country | |
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60837783 | Aug 2006 | US |