US3895448A

US3895448A - Dry coke cooler

Info

Publication number: US3895448A
Application number: US426248A
Authority: US
Inventors: Albert G Jonnet
Original assignee: Koppers Co Inc
Current assignee: Raymond Kaiser Engineers Inc
Priority date: 1973-12-19
Filing date: 1973-12-19
Publication date: 1975-07-22
Anticipated expiration: 1992-07-22
Also published as: DE2455496A1; DE2455496C2; JPS5092901A; GB1483241A; JPS5745275B2

Abstract

In a dry coke cooler, the coke discharges continually from a ''''coke leg'''' at the bottom. A portion of the recycle gases entering the cooler, pass through the coke leg and then flow into a conduit carrying recycle gases entering the cooler.

Description

United States Patent 1191 J onnet 1451 July 22, 1975 DRY COKE COOLER [75] Inventor: Albert G. Jonnet, Pittsburgh, Pa.

[73] Assignee: Koppers Company, Inc., Pittsburgh,

22 Filed: Dec. 19, 1973 21 Appl. No.: 426,248

[52] US. Cl. 34/65; 202/228; 202/263 [51] Int. Cl ClOb 39/02 [58] Field of Search 34/13, 20, 64, 65, 169; 202/228, 263

[56] References Cited UNITED STATES PATENTS 1,496,094 6/1924 Moetteli 202/228 1,661,211 3/1928 Wussow 202/228 2,048,193 7/1936 Moetteli 202/228 3,435,596 4/1969 I-Iornung 202/263 3,716,150 2/1973 Echterhoff et 211..., 202/263 3,731,398 5/1973 Nicms 34/169 3,774,315 11/1973 Schmalfeild et a1. 202/228 3,795,937 3/1974 Kemmetmueller 34/13 FOREIGN PATENTS OR APPLICATIONS 1,061,412 3/1967 United Kingdom 202/228 282,286 12/1927 United Kingdom 202/228 256,727 8/1926 United Kingdom 202/228 458,513 3/1928 Germany 202/228 Primary Examiner-William L. Freeh Assistant ExaminerPaul Devinsky Attorney, Agent, or Firm Sherman H. Barber; Olin E. Williams; Oscar B. Brumback [57] ABSTRACT In a dry coke cooler, the coke discharges continually from a coke leg at the bottom. A portion of the recycle gases entering the cooler, pass through the coke leg and then flow into a conduit carrying recycle gases entering the cooler.

2 Claims, 1 Drawing Figure DRY COKE COOLER BACKGROUND or THE INVENTION In known systems for the dry quenching of coke. as contrasted with conventional systems for the wet quenching of coke, the hot gasses generated by the coke in the cooler are withdrawn therefrom. partially cooled and then recirculated in the cooler. The partially cooled gases flow counter currently through the coke bed in the vertical coke cooler. The coke gravitates in the coke cooler where it is cooled by the recirculating gaseous medium. The gaseous medium, under moderate pressure, is blown into the cooler near its bottom through a distributor located on the vertical centerline of the cooler.

The cooled coke gravitates through an opening in the bottom of the cooler onto a distributor and a conveyor.

The gaseous medium used to dry quench the coke is toxic and combustible, containing about to per cent carbon monoxide. It is important therefore that the gaseous medium be prevented from escaping into the atmosphere around the cooler.

Since the gas pressure at the top of the conventional cooler is maintained normally at or near atmospheric pressure, the gas pressure at the bottom of the coke bed in the cooler, at the gas inlet, is usually 8 to 12 inches water column above atmospheric pressure in order to overcome the frictional loss through the coke bed.

Since the gas pressure at the bottom of the conventional cooler is above atmospheric pressure, as noted herein. it is customary to provide a rather elaborate. double sealing. valve arrangement, that discharges coke batchwise from the cooler in order to prevent the free flow of gases from the cooler.

The present invention, however, discloses an improvement in the usual dry coke cooler that is both novel and unobvious from the known prior art.

BRIEF SUMMARY OF THE INVENTION A dry coke cooling apparatus has a coke leg at the bottom of a cooling chamber and cooling gases flowing into the chamber pass through the coke leg and exit therefrom. through a conduit that carries the exiting gases into a fan inlet. The fan urges recycled gases into the chamber to cool the coke therein. The pressure at the bottom of the coke leg is substantially atmospheric whereby conventional air locks are not necessary and coke discharges from the chamber continually and not batchwise.

For a further understanding of the invention and for features and advantages thereof, reference may be made to the following description and the drawing which illustrates a preferred embodiment of equipment in accordance with the invention.

BRIEF DESCRIPTION OF THE DRAWING The drawing illustrates schematically a dry coke cooling apparatus in accordance with one embodiment of the invention.

DETAILED DESCRIPTION Referring to the drawing. a dry coke cooler 11, in accordance with the invention. comprises a vertically arranged vesscl or chamber having a cylindrical shaft or shell 13 comprising a main body portion, a frustoconical top or prechamber l5, and a frusto-conical bottom l7.

Within the cylindrical shaft or shell portion 13 there is, near the top thereof and below the prechamber 15, an annular passageway 19 that surrounds the entire periphery of the shell 13. A plurality of ports 21 in the shell 13 allow gases generated by hot coke within the shell to escape into the annular passageway 19.

Within the shell 13 there is also an inverted frustoconical member 23 that is connected to the shell 13 about where shown, and that has an open bottom. Another frusto-conical member 25, having a perforated surface, connects to the open small end of the frustoconical member 23 and to the shell 13, as shown. The two interconnected frusto-

conical members

23, 25, together with the shell 13, form an annular gas passageway 27 within the shell 13.

Below the lower or bottom frusto-conical member 17 there is a coke leg including a transitional member 29 that connects to such frusto-conical member 17 and a receiver 31. The receiver 31 is provided with a gas outlet connection 33 and an inclined chute 35.

The interior surfaces of the shell 13, the frustoconical member 23, the bottom 17, the transitional member 29, the receiver 31, and the chute 35, are lined with a suitable refractory material 37. Also the inner surface of the steel structure forming the annular passageway 19, as well as the inner surface of the top 15, are lined with such refractory material 37.

The annular passageway 19 communicates with a conduit 39 that leads gases generated by the hot coke within the shell 13 into a plenum 41. Within the plenum 41 there is a vertically arranged baffle 43 which may be of suitable refractory material or of steel coated with a suitable refractory material. The interior surfaces of the conduit 39 and the plenum 41 are also lined with the refractory material 37.

The plenum 41 is fitted with a discharge conduit 45 having a valve member or flow control device 47 therein. Also the plenum communicates with a conduit 49 that carries the gases into a conventional waste heat boiler 51.

The gases in conventional manner, then pass through the boiler and flow through conduit 53 to an evaporator 55; thence through conduit 57 to a cyclone separator 59; and thence through conduit 61 to a motorized fan 63. From the fan 63, the gases flow in conduit 65 into the annular passageway 27. The gases. of course, have given up most of their heat during the passage de scribed and enter the annular passageway 27 at a considerably lower temperature than the temperature of the coke within the shell 13.

A conduit 67 joins the gas outlet connection 33 with the conduit 61 at a point just ahead of the fan 63. Thus, the fan 63 receives gases from the coke leg through both conduit 67 and conduit 61. A small cyclone-type separator 69 is installed in the conduit 67, about where shown in the drawing. to remove particulate matter from the gases flowing in conduit 67.

In operation, a quantity of coke that has just been pushed from a coke oven chamber is introduced into the coke cooler through the opening in the top or prechamber 15. The top line of the new hot coke and the coke in the chamber that is cooling, is shown at 71 in the drawing.

Gases which are generated from the hot coke in the chamber, and recirculated gases flowing thereinto from the conduit 65 and the annular passageway 27, flow from the chamber through the several ports 21 into the annular passageway 19. From there the gases travel into the plenum 41, and heavy particles in the gases hit the baffle 43 and gravitate into the bottom of the plenum from which they are removed through the conduit 45.

The hot gases pass through the boiler and the other several pieces of apparatus and conduits as mentioned previously.

The recirculated and cooled gases. under moderate pressure. then flow into and upwardly through the coke and cool it.

The cooled coke gravitates through the coke leg onto the chute 35 and thence onto a suitable conveyor 73 that carries the cooled coke thence.

Some portion of the recirculated cooling and quenching gases. about 5 percent entering the chamber through conduit 65, flow downwardly in the coke leg and thence through the conduit 67 into the separator 69. This small gas portion re-enters the fan 63 at the inlet side through conduit 61, as shown in the drawing.

The pressure drop of the gases flowing in the coke leg is equal to the pressure difference between the gas inlet pressure to the chamber and the outside ambient pressure (atmospheric). Thus. the pressure at the bottom of the coke leg. where the coke gravitates onto the chute 35. is substantially atmospheric pressure. Hence. no conventionally used air locks are required. and the coke is not discharged in batches. as is conventional in the usual dry coke cooler apparatus.

In one embodiment of the invention. comprising a coke leg. wherein the pressure drop of 5 percent of the gas flow into the cooleris to atmospheric pressure. would have a reduced cross sectional area of 16 square feet when the cooler chamber has a diameter of feet. The coke leg would be about 10 feet long in a coke cooler of the same size.

The small gas stream flowing in conduit 67 is controlled by an automatic pressure controller 75 in order to maintain atmospheric pressure at the discharge end of the coke leg. The automatic pressure controller 75 may be any one of several conventional units. One suitable unit is described in Bulletin No. 76. issued by Continental Equipment Co.. of Coraopolis. Pa.. which company is a division of Fisher Govcnor Co. Associated with such pressure controller is a recording pressure controller. designated as circle-P in the drawing that is marketed by Foxboro Co.. of Foxboro. Mass. and that is designated as Model in their Bulletin 3-181.

In a modification of the present invention. a separate small fan. F. (77) is installed in conduit 79 (shown by dotted lines in the drawing) connecting the conduit 67 with the conduit 49. Thus. any air that may be drawn into the bottom of the coke leg through the action of the fan 77, mixes with the gases in the conduit 49, and this mixture is carried into the boiler 51 and the other equipment.

From the foregoing description of one embodiment and a modification of the invention, those skilled in the art should recognize many important features and advantages of it. among which the following are particularly significant:

That conventional air locks at the bottom of ordinary dry coke cooling chambers are unnecessary in the cooling chamber of the present invention;

That. because there are no such conventional air locks in the present invention. the operation of the cooling chamber of the present invention is continuous and not batchwise as is customary:

That the cooling height of the chamber of the present invention, extending from a point near the coke discharge at ground or yard level to the prechamber. is greater than the cooling height of conventional dry coke cooling chambers. so that better and faster cooling takes place; and

That only a minimum amount of dust is given off at the outlet of the cooler chamber while coke discharges from the coke leg.

Although the invention has been described herein with a certain degree of particularity it is understood that the present disclosure has been made only an example and that the scope of the invention is defined by what is hereinafter claimed.

What is claimed is:

1. A vertical dry coke cooler having a cooling chamber holding hot coke in which recycle gases flow counter currently through the chamber to cool said coke. wherein the improvment comprises:

a. a coke leg at the discharge end of said cooling chamber including means to continvously discharge the cooled coke.

b. a first conduit leading from the discharge end of said coke leg for recycling gases from said discharge end.

c. a second conduit for carrying hot gases generated by the coke leading from the coke cooling chamber. said second conduit having gas cooling means.

d. a third conduit joining said first a second conduits and carrying'the combined discharge end recycle gases and cooling chamber recycle gases into said cooling chamber and said discharge leg, wherein a major portion of said gases is carried into the cooling chamber.

e. an automatic pressure controller in said first conduit including means operable to maintain substantially atmospheric pressure at the discharge end of said coke leg.

2. The invention of claim 1 including:

a. a separator in said first conduit that removes particulate matter from the gases flowing in said first

Claims

1. A vertical dry coke cooler having a cooling chamber holding hot coke in which recycle gases flow counter currently through the chamber to cool said coke, wherein the improvment comprises: a. a coke leg at the discharge end of said cooling chamber including means to continvously discharge the cooled coke, b. a first conDuit leading from the discharge end of said coke leg for recycling gases from said discharge end, c. a second conduit for carrying hot gases generated by the coke leading from the coke cooling chamber, said second conduit having gas cooling means, d. a third conduit joining said first a second conduits and carrying the combined discharge end recycle gases and cooling chamber recycle gases into said cooling chamber and said discharge leg, wherein a major portion of said gases is carried into the cooling chamber. e. an automatic pressure controller in said first conduit including means operable to maintain substantially atmospheric pressure at the discharge end of said coke leg.

2. The invention of claim 1 including: a. a separator in said first conduit that removes particulate matter from the gases flowing in said first conduit.