Nozzle tip for pulverized coal burner

• US 4,520,739 A
• Filed: 09/13/1982
• Issued: 06/04/1985
• Est. Priority Date: 07/12/1982
• Status: Expired due to Term

• Current Assignee: ALSTOM Power Inc. (General Electric Company)
• Original Assignee: Combustion Engineering Incorporated (ABB Limited)
• Inventors: McCartney, Michael S., Chadshay, Roman, Erlacher, Richard F.
• Primary Examiner(s): Favors, Edward G.
• Application Number:
  US06/555,462
• Time in Patent Office: 995 Days
• Field of Search: 110/263, 110/264, 110/347, 122/479 B, 239/587, 239/590, 239/591, 239/600
• US Class Current: 110/263
• CPC Class Codes: F23D 1/00 Burners for combustion of pulverulent fuel disposition of burners F23C
• CPC Class Codes: F23D 2201/101 tiltable

Abstract

An improved nozzle tip (10) for a burner on a pulverized coal-fired furnace for receiving a stream of pulverized coal and air discharging from the coal delivery pipe (50) of the burner and directing the pulverized fuel and air stream into the furnace, is comprised of a base body (20), a replaceable highly abrasion resistant insert (30), and a replaceable highly temperature resistant end cap (40) which is readily attachable by mechanical means (28, 48) to the base body with the abrasion resistant insert disposed therein. The insert defines a highly abrasion resistant flow conduit through the nozzle tip from the discharge end of the base body to the receiving end of the end cap through which the pulverized fuel and air stream passes from the burner into the furnace.

Claims

1. A nozzle tip for a burner on a pulverized fuel-fired furnace for receiving a stream of pulverized fuel and air discharging from the burner and directing said pulverized fuel and air stream into the furnace, comprising:

a. a hollow, open-ended base body adapted to be mounted to the discharge end of the burner having an outer shell and an inner shell disposed substantially coaxially in spaced relationship within the outer shell so as to define a first flow passage through the interior of the inner shell and a second flow passage through the annular space between the inner and outer shells;

b. a replaceable, hollow, open-ended end cap removably mounted to said base body at the discharge end thereof and having an outer shell and an inner shell disposed substantially coaxially in spaced relationship within the outer shell so as to define a first flow passage through the interior of the inner shell and a second flow passage through the annular space between the inner and outer shells; and

c. a replaceable, hollow, open-ended insert of a highly abrasion resistant material disposed intermediate of said base body and said end cap and retained in position therebetween by said base body and said end cap, said insert having an inlet end mating with an abutting against the discharge end of the inner shell of said base body and an outlet end mating with and abutting against the receiving end of the inner shell of said end cap, said insert defining a highly abrasion resistant flow conduit through the nozzle tip from the discharge end of the first flow passage of said base body to the receiving end of the first flow passage of said end cap through which the pulverized fuel and air stream passes from the burner into the furnace.

2. A nozzle tip for a burner on a pulverized fuel-fired furnace for receiving a stream of pulverized fuel and air discharging from the burner and directing said pulverized fuel and air stream into the furnace, comprising:

a. a hollow, open-ended base body adapted to be pivotally mounted to the discharge end of the burner having an outer shell and an inner shell disposed substantially coaxially in spaced relationship within the outer shell so as to define a first flow passage through the interior of the inner shell and a second flow passage through the annular space between the inner and outer shells;

b. a replaceable, hollow, open-ended end cap having an outer shell and an inner shell disposed substantially coaxially in spaced relationship within the outer shell so as to define a first flow passage through the interior of the inner shell and a second flow passage through the annular space between the inner and outer shells;

c. a replaceable, hollow, open-ended, weld-free insert cast of a highly abrasion resistant material having an inlet end and an outlet end, said cast insert disposed intermediate of said base body and said end cap with its inlet end mating with and abutting against the discharge end of the inner shell of said base body and its outlet end mating with and abutting against the receiving end of the inner shell of said end cap thereby defining a first flow conduit formed of the first flow passage of said base body, the interior of said cast insert and the first flow passage of said end cap through which the pulverized fuel and air stream passes from the burner into the furnace; and

d. means for removably attaching said end cap to said base body with said cast insert secured therebetween so as to mate the outer shell of said end cap with the outer shell of said base body thereby defining a second flow conduit formed of the second flow passage of said base body and the second flow passage of said end cap through which additional air passes into the furnace.

3. A nozzle tip as recited in claim 2 wherein said replaceable, hollow, open-ended, weld-free, cast insert is tapered inwardly from its receiving end adjacent said base body to its discharge end adjacent said end cap thereby defining an inwardly tapering flow conduit through the nozzle tip from the discharge end of said base body to the receiving end of said end cap.

4. A nozzle tip as recited in claim 3 wherein said means for removably attaching said end cap to said base body comprises:

a. first plurality of plate-like members disposed transversely between the inner and outer shells of said base body and extending therefrom in a direction toward said end cap, said first members having a hole therethrough;

b. a second plurality of plate-like members disposed transversely between the inner and outer shells of said end cap and extending therefrom in a direction toward said base body, said second members having a hole therethrough disposed so as to coincide with the hole in one of said first members when said end cap is mated to said base body; and

c. removable securing means disposed through the coincident holes of said first and second members for mounting said end cap to said base body.

5. A nozzle tip as recited in claim 4 wherein each of the second plurality of plate-like members disposed transversely between the inner and outer shells of said end cap and extending therefrom in a direction toward said base body engages the lateral surface of said cast insert disposed intermediate said end cap and said base body.

6. A nozzle tip as recited in claims 2, 3, 4 or 5 wherein said base body is comprised of stainless steel which is particularly abrasion resistant and said replaceable end cap is comprised of stainless steel which is particularly temperature resistant.

7. A nozzle tip as recited in claim 6 wherein said replaceable, hollow, open-ended, weld-free, cast insert is cast as a single piece of Ni-Hard material.

8. An abrasion resistant insert for lining a coal nozzle tip comprising a hollow, open-ended, weld-free shell cast of abrasion resistant material in the shape of a frustum of a rectangular pyramid defining therethrough a tapering flow passage, said shell having at least one integrally cast, weld-free splitter plate disposed within the tapering flow passage so as to subdivide the tapering flow passage into multiple passages.

9. An abrasion resistant insert as recited in claim 8 wherein the splitter plate disposed within the tapering flow passage extends externally therefrom through the larger of the open ends of the frustum shaped shell.

10. An abrasion resistant insert as recited in claim 8 or 9 wherein said insert is cast as a single piece of Ni-Hard material.

11. A replaceable end cap for mounting to a coal nozzle tip comprising:

a. a hollow, open-ended outer shell;

b. a hollow, open-ended inner shell disposed substantially coaxially in spaced relationship within the outer shell so as to define a first flow passage through the inner shell and a second flow passage through the annular space between the inner and outer shells;

c. at least one splitter plate disposed within the inner shell so as to subdivide the first flow passage therethrough into multiple passages; and

d. a plurality of plate-like members disposed transversely between the inner and outer shells and extending therefrom for engaging and mounting to said coal nozzle tip.

12. A replaceable end cap is recited in claim 11 comprised of stainless steel which is particularly temperature resistant.

13. An abrasion resistant insert for lining a coal nozzle tip comprising a hollow, open-ended shell of abrasion resistant material in the shape of a frustum of a rectangular pyramid defining therethrough a flow passage, said shell having at least one splitter plate disposed within the flow passage so as to subdivide the flow passage into multiple passages, said splitter plate extending externally from the flow passage through the larger of the open ends of the frustum shaped shell.