Patent Application
20120317992
The present application and the resultant patent relate generally to combined cycle power systems and more specifically relates to an improved cooling water channel for a feed injector of a gasification system that may avoid localized strain and associated cracking.
Combined cycle power systems generally include a gasification system that is integrated with a gas turbine engine. Known gasification systems convert a mixture of fuel, air/oxygen, steam, and/or other materials into an output of a partially oxidized gas known as a “syngas.” Known gasification systems generally use a teed injector to supply a mixture stream into a reactor vessel. Known feed injectors may be exposed to temperature extremes within the reactor vessels. Specifically, the tips of the feed injectors may be exposed to reaction temperatures that may inhibit effective operation of the injectors and/or shorten the life span thereof. Further, the feed injectors generally may be exposed to corrosive elements in the syngas flowing within the reactor vessel.
In order to protect the feed injectors, known gasification systems may use a closed loop water supply system to provide cooling water to the feed injector. Providing cooling water to the known feed injectors, however, may produce areas of localized strain and associated cracking. Specifically, the metal temperatures between an internal oxygen passage and an internal cooling water channel about the tip area may be relatively low as compared to the metal temperatures of the outside face about the combustion zone. Such temperature differences may be a multiple of about ten (10) times or so. The stiffness of the metal on the hot side thus decreases as the temperature increases. The hot side therefore may elongate more than the cool side and result in an area of high plastic strain therebetween. This area of high plastic strain may result in cracking or other damage therein. The time and effort required to repair such damage may be considerable.
There is thus a desire for an improved feed injector design for a gasification system. Such an improved feed injector design may reduce areas of plastic strain therein so as to reduce cracking and other types of damage. Reduced cracking may in turn provide reduced overall system downtime, repair costs, and increased component lifetime.
The present application and the resultant patent thus provide a feed injector nozzle for a gasification system with a reaction zone therein. The feed injector nozzle may include a number of tubes extending towards the reaction zone. The tubes may define a number of passages therebetween. A cooling water channel may extend through one of the tubes. The cooling water channel may include a first side adjacent to one of the passages and a second side adjacent to the reaction zone. The first side may include a first side thickness and the second side may include a second side thickness with the first side thickness being less than or equal to the second side thickness.
The present application and the resultant patent further provide a gasifier for a combined cycle power system. The gasifier may include a vessel body, a reaction zone within the vessel body, and a feed injector extending into the vessel body about the reaction zone. The feed injector may include a nozzle tip with a cooling water channel therein. The cooling water channel may include a first side and a second side adjacent to the reaction zone. The first side may include a first side thickness and the second side may include a second side thickness such that the first side thickness is less than or equal to the second side thickness.
The present application and the resultant patent further provide a feed injector nozzle for a gasification system with a reaction zone therein. The feed injector nozzle may include a number of tubes extending towards the reaction zone. The tubes may define a number of passages therebetween. A cooling water channel may extend through one of the tubes. The cooling water channel may include a cool side adjacent to an oxygen passage and a hot side adjacent to the reaction zone. The cool side may include a cool side thickness and the hot side may include a hot side thickness such that the cool side thickness is less than or equal to the hot side thickness.
These and other features and improvements of the present application and the resultant patent will become apparent to one of ordinary skill in the art upon review of the following detailed description when taken in conjunction with the several drawings and the appended claims.
Referring now to the drawings in which like numerals refer to like elements throughout the several views,
The compressor 15 compresses an ambient air flow that is channeled to the air separation unit 20. Alternatively, a compressed flow of air from a compressor 40 of the gas turbine engine 30 also may be used. The air separation unit 20 uses the compressed air to generate oxygen for use by the gasifier 25. The oxygen flow is used in the gasifier 25 in generating the partially oxidized syngas. A flow of nitrogen process gas from the air separation unit 20 also may be forwarded to a combustor 45 of the gas turbine engine 30 for use in reducing emissions and the like.
Specifically, the gasifier 25 converts a mixture of fuel, oxygen, steam, and/or other materials into an output of syngas for use by the gas turbine engine 30. The syngas may flow to the combustor 45 via a cleanup device 50. The cleanup device 50 may separate carbon dioxide and the like therein. The syngas may be combusted in the combustor 45 so as to produce a stream of hot combustion gases. The hot combustion gases drive a turbine 55 so as to produce mechanical work. The mechanical work produced by the turbine 55 drives the compressor 40 and an external load such as an electrical generator 60 and the like. The exhaust gases from the turbine 55 also may be channeled to a heat recovery steam generator 65. The heat recovery steam generator 65 generates steam for driving the steam turbine 35. The steam turbine 35 may drive a further load 70. A further supply of steam may be sent by the heat recovery steam generator 65 to the gasifier 25 so as to facilitate cooling of the syngas. Other components and other configurations may be used herein.
The cool side 210 may have a cross-sectional thickness 260 that may be equal to or greater than a hot side thickness 270. Because the hot side 230 faces temperatures much higher than the cool side 210 by a multiple, the stiffness of the cool side 210 thus may be much greater than the stiffness of the hot side 230. The hot side 230 therefore may elongate to a degree greater than the cool side 210 so as to create the area of maximum strain 250.
It should be apparent that the foregoing relates only to certain embodiments of the present application and the resultant patent. Numerous changes and modifications may be made herein by one of ordinary skill in the art without departing from the general spirit and scope of the invention as defined by the following claims and the equivalents thereof.
