Apparatus and methods for large particle ash separation from flue gas using screens having semi-elliptical cylinder surfaces
View Patent ↗Apparatus for separating ash particles from a flue gas. The apparatus includes a screen that has a plurality of semi-elliptical cylinder surfaces. The semi-elliptical cylinder surfaces having holes through which said flue gas flows and through which the ash particles will not pass. The screen has a single layer for performing the separation in a manner such that the ash particles fall away from the screen and collect outside of the screen. A method of reducing velocity of a flue gas passing through screening apparatus for separating flue gas from ash particles. The method includes replacing a first screen of the screening apparatus with a second screen that has a plurality of semi-elliptical cylinder surfaces.
1. A method of reducing velocity of a flue gas passing through screening apparatus for separating flue gas from ash particles; said method comprising:
replacing a first screen of said screening apparatus with a second screen comprising a plurality of semi-elliptical cylinder surfaces, said semi-elliptical cylinder surfaces having holes adapted for said flue gas to flow and through which said ash particles will not pass.
2. The method of claim 1 wherein said first screen is selected from a list consisting of: a pleated screen and a flat screen.
3. The method of claim 1 wherein said second screen further comprises a flat screen on each end of each semi-elliptical cylinder surface, said flat screens having holes through which said flue gas flows and through which said ash particles will not pass.
4. The method of claim 1 wherein said velocity is reduced by up to 40 percent.
5. The method of claim 1 wherein a pressure drop in said screening apparatus is reduced by up to 60 percent.
6. The method of claim 1 wherein said holes of said second screen comprises a cross sectional area of about 1 mm 2 -200 mm 2 .
7. The method of claim 1 further comprising:
flowing a mixture of flue gas and ash particles toward said second screen.
8. The method of claim 7 further comprising:
collecting said ash particles in a hopper after said ash particles are separated from said flue gas by said second screen.
9. The method of claim 7 wherein said flue gas is flowed from a side of said second screen on which foci points of said semi-elliptical cylinder surfaces lie.
10. The method of claim 7 wherein said flue gas is flowed from an opposite side of said second screen on which foci points of said semi-elliptical cylinder surfaces lie.
11. The method of claim 1 wherein said second screen comprises concave semi-elliptical surfaces and convex semi-elliptical surfaces.
12. The method of claim 1 further comprising:
determining which of a concave semi-elliptical cylinder design and a convex semi-elliptical cylinder design is more efficient for a particular application; and
applying the more efficient design to the application.