US3777679A

US3777679A - Incinerating process

Info

Publication number: US3777679A
Application number: US00244527A
Authority: US
Inventors: Z Przewalski
Original assignee: Individual
Current assignee: M&S Engineering and Manufacturing Co Inc
Priority date: 1972-04-17
Filing date: 1972-04-17
Publication date: 1973-12-11
Anticipated expiration: 1990-12-11

Abstract

An incinerating system for recovering copper wire following the burning of the insulation therefor as combustible waste while simultaneously insuring against wire overheating including the steps of: first burning the insulated wire in an ignition chamber, second preheating the secondary chamber, and third exploiting the fuel generated in the ignition chamber for maintaining the temperature of the secondary chamber while passing the smoke generated in the ignition chamber through the secondary chamber preliminary to passage to atmosphere.

Description

United States Patent 1 1 Przewalski INCINERATING PROCESS [76] Inventor: Zygmunt J. Przewalski, 22 Brewster Rd., Windsor, Conn, 06095 22 Filed: Apr. 17, 1972 211 Appl. No.: 244,527

52 US. Cl. "1 10/8 A, 110/18 1' [51] Int. Cl. F23g 7/00 [58] Field of Search 72/75; 110/18 R, 110/8 A [56] References Cited UNITED STATES PATENTS 3,076,421 2/1963 Spitz 110/18 2,815,278 12/1957 Wilkins 75/72 FOREIGN PATENTS OR APPLICATIONS 1,206,421 9/1970 Great Britain 110/18 1 Dec. 11, 1973 Primary Examinerl(enneth W. Sprague Attorneyl(enwood Ross et al.

[57] ABSTRACT An incinerating system for recovering copper wire following the burning of the insulation therefor as combustible waste while simultaneously insuring against wire overheating including the steps of: first burning the insulated wire in an ignition chamber, second preheating the secondary chamber, and third exploiting the fuel generated in the ignition chamber for maintaining the temperature of the secondary chamber while passing the smoke generated in the ignition chamber through the secondary chamber preliminary to passage to atmosphere. I

2 Claims, 7 Drawing Figures PMENIEU DEC 1 1 I975 SIiLU 2 EF 5 PAIENTEDnEc 1 1 :915

SLLZT 3 E FIG. 4.

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PAIENTED 0E6] I 8975 1 lNCINERATlNG-PROCESS This invention relates to an incinerator of new and novel construction capable of burning materials in a more efficient manner than has been heretofore possible, and allowing the utilization of the heat generated by the burner for aiding the afterburning of the generated combustible gases under controlled conditions of oxygen supply and temperature so as to provide optimum incineration conditions.

The invention has particular reference to equipment facilitating the recovery of secondary matter, i.e., copper wire, the primary matter, i.e., the insulation circumscribing the wire, being desirably burned as combustible waste, it being borne in mind that, in order so to obtain reclaimed metal having any respectable commercial value, overheating must be insured against. To this end, the invention comprehends equipment which allows the burning of the insulation at a low temperature and in a so-called reducing atmosphere, that is, an atmosphere not conducive to the promotion of metal oxidation, ergo the possibility of obtaining a high quality of reclaimed metal with a minimum of loss through oxidation, with all of this being accomplished economically with respect to a minimum of auxiliary fuel consumption.

The heat exploited in the invention is obtained from the actual burning process, there being enough fuel generated in a so-called primary or ignition chamber that a so-called secondary or afterburner chamber, oncepreheated, maintains its own temperature, wherefor an auxiliary burner means servicing that secondary chamber is called upon to function only during the preheating phase or, in the case of continuous or batch feeding, only during preheating and during reloading intervals when the incinerator may be recharged with a next-succeeding charge of the materials being incinerated.

The invention teaches techniques for preventing smoke, generated during a tirst-in-time ignition period, from passing outwardly of the incinerator without first passage through the afterburner for further burning during a second-in-time combustion period and thence through a scrubber means for cleaning the exhaust gases from their particulate components in final attainment of a pollution-free operation.

lncinerators heretofore employed as means for the disposal of waste materials have possessed many disadvantages. They have each emitted considerable amounts of heavy smoke and other obnoxious waste products of combustion into the atmosphere so as to be hazardous to community health and to create economic problems with respect to property maintenance in adjacent areas as such products of combustion not only soil virtually everything with which they come into contact but also tend to enhance or hasten property deterioration. The objected to waste products of combustion are in the form of unburned carbon which gives rise to the heavy dark smoke and gases and other obnoxious vapors generated during burning. The large amount of carbon present in the waste products is due to the incomplete or inefficient combustion during the actual burning brought about by the structure of the incinerator itself, or resultant from insufficient heat in the burning zone so as to allow efficient operation and- /or from insufficient oxygen to support the desired degree of combustion and insure a complete consumption of the material being burned. Too, a unit capable of burning a large volume of waste material is extremely expensive in initial cost as well as upkeep. Furthermore, any residue remaining after burning cannot be readily removed so as to result oftentimes in a shutdown with a corresponding cooling in order to permit cleaning before further burning can be effected. And still another problem is that the heat generated during burning of the waste material is totally lost.

With a view toward the elimination of the previously mentioned and related disadvantages, it is therefore a principal object hereof to provide an incinerator of a new and novel structure and operating on a new principle so as to offer a more efficient operation than heretofore possible with prior incinerators.

When air is not supplied whatever, burning of course cannot ensue. Smoke is generated when and if burning is too rapid or air supply is insufficient. Under insufficiency of air conditions, burning proceeds, but with an excess of the volatiles, meaning the production of more smoke. Likewise, if too must air is supplied, the resultant effect is one of temperature cooling, thus slowing the reaction and resulting in incomplete burning.

Thespeed of burning or reaction time is directly proportional to oxygen supply as well as to temperature, leading to the truism that complete and optimum burning dictates not only a sufficiency of air but also a sufficiently high degree of temperature.

The desideratum hereof is to allow optimum incineration in such manner that the generated smoke is burned completely due to a determination and attainment ofa certain ratio of the gases (air) and the volatile combustibles (smoke) and the operating temperatures.

The invention comprehends primary and secondary burning arrangements which effectively handle the effluent from the burning of wastes and additionally take care of and remove any suspended solids or other particles from the emission arising from the burning or incinerating unit. These arrangements have been found to be particularly useful in the controlling of the air supply and temperature, especially in the exemplified case of burning copper wire in the desirable process of copper recovery. In such instance, too low an operating temperature would mean inadequate burning; too high a temperature would mean copper embrittlement.

The material to be processed, preferably loaded in work baskets, is placed into the primary incinerator chamber from an entry or charge end, whereat the load is ignited by an ignition burner and where, once ignited, the burning is controlled automatically.

Means are provided within the primary chamber for proportioning the supply of air so that too rapid burning with its resultant overproduction of smoke is precluded and for spraying a coolant in manner such that a desirable low temperature level is maintained with a resultant control of the smoke production therein.

Gases and smoke generated by the load are first burned in the primary chamber and are next charged in a controlled flow through breachings to the secondary chamber under the benefit of the heat generated within the primary chamber and under conditions of a thorough mixing of the products of combustion with makeup air at an automatically controlled temperature so as completely to burn all of the gases and smoke, with the secondary chamber being preheated by the geometry of the incinerator and with the air being admitted thereto through a preheated arched wall defining the breached intervening member between the chambers, the air serves to expedite the reaction time without the requirement of an oversupply of supplemental air.

Emission from the primary ignition unit is collected as close as possible to the outlet thereof and such smoke is then passed as hot polluted gases through the secondary combustion unit where the stream is desirably provided with a burning arrangement so that suspended or volatile combustible materials or solids are consumed.

In essence, I achieve the creation of a predetermined temperature condition in the secondary chamber and a controlled ratio between the volume of smoke generated in the primary chamber and passed into the secondary chamber and of air introduced into the secondary chamber.

By the arrangement, I avoid the excessive use of an auxiliary fuel in the control of the smoke during ignition and combustion.

Because even after complete combustion and the elimination of all visible pollutants, the effluent could contain invisible gases, auxiliary exhaust means are additionally provided so as further to aid in the avoidance of smoke production and in the flow of heat from the ignition chamber to the afterburner chamber to accelerate the reaction time in the latter and to eliminate the invisible emissions and pollutants, some being operative with a minimum water consumption and avoiding any discharge to a sewer system of water polluted with any effluent contaminants.

To the accomplishment of these ends, the invention consists of the means and techniques hereinafter fully described in the subjoined claims, annexed drawings and following description setting forth in detail certain means for carrying out invention, all illustrating, however, only but one of the various ways in which the principles of the invention may be employed.

In the accompanying drawings:

FIG. 1 is a graphical representation ofa single charge operation illustrating burning by the fire control method of the invention;

FIG. 2 is a graphical representation ofa multi-basket charge operation illustrating the continuous feeding and burning by the fire control method of the invention;

FIG. 3 is a view, in side elevation, of the incinerator and stack, with certain features or parts being illustrated in dotted line configuration;

FIG. 4 is a view, in end elevation, showing the incinerator and stack and scrubber, taken from the charge or entry end;

FIG. 5 is a view, in top plan, showing the incinerator and stack and scrubber;

FIG. 6 is a view, in perspective, of the scrubber, and

FIG. 7 is a view, in section, through the scrubber shown in FIG. 6.

With reference to the graph in FIG. 1 showing what takes place in a single charge operation over a time span of 90 minutes from the moment when the incinerator is initially charged, the X axis is the number line representative of time in minutes from zero to 90 minutes and the Y axis is the number line representative of temperature in degrees from zero to 1800F, with the two axes intersecting at their zero points.

The solid line denotes the primary or ignition chamber temperature showing a steady rise from zero first to a level denoted by line BB which is representative of the predetermined maximum temperature (say 1600") of the primary chamber for the burning of a particular product, as, for example, copper wire in the attainment ofa quality copper in the process of burning the insulation material away therefrom. The level denoted by line A-A is representative of the predetermined higher temperature (say l800F) of the secondary or afterburner chamber as determined to be required in order to achieve a complete burning of the smoke.

The solid line will be observed to extend upwardly of level BB but not quite to reach level AA when it commences to drop off gradually continuing to drop off throughout the balance of the ninety minute incinerating period.

The dash line on the other hand represents the secondary (after burner) chamber temperature without the use of auxiliary fuel. It will be noted to rise not quite as fast from zero to level AA where it then proceeds to drop off gradually over the ninety minute incinerating period.

The area denoted by the cross hatching is representative of the auxiliary fuel consumption in order to obtain the desired smokeless burning.

The auxiliary fuel is used only for purposes of preheating as denoted by the cross hatched area to the left of the peak of the dash line.

The graph in FIG. 2 shows what takes place in a plural charge operation over a time span of minutes from the moment when the incinerator is initially charged and during which interval four separate charges are introduced in seriatim at 30 minute intervals, the X axis being the number line representative of time in minutes from zero to 90 minutes and the Y axis being the number line representative of temperature in degrees from 0 to 1600F.

The solid line in the case of each batch denotes the primary or ignition chamber temperature showing a steady rise from zero first to a level denoted by line BB, representative of the predetermined maximum temperature of the primary chamber for the burning of a particular product, and less than the level denoted by line AA, representative of the predetermined higher temperature of the secondary or afterburner chamber as determined to be required in order to achieve a complete burning of the smoke.

The solid line will be observed to extend toward level BB where it levels off and then drops off gradually over the ninety minute incinerating period.

The dash line on the other hand represents the secondary (after burner) chamber temperature without the use of auxiliary fuel. It will be noted to rise not quite as fast from zero to level AA where it levels off and then drops off gradually over the ninety minute incinerating period.

The auxiliary fuel is used only for the purpose of preheating as denoted by the cross hatched area to the left of the peak of the dash line.

Referring now to FIG. 3 showing the incinerator in side elevation, same is seen to comprise a steel outer shell or housing consisting of a pair of spaced generally vertically extending

side walls

10, 10, a pair of spaced vertical end (front entrance and rear exit)

walls

12, 14 respectively, and a pair of spaced horizontal cover (lower and upper)

walls

16, 18 respectively, all in the form of a usual type of housing, and secured together as by strategically located vertically and horizontally disposed

beams

20, 22 respectively.

The outer shell or housing is provided with an intermediate insulating layer of some suitable material such as asbestos and an innermost lining of fire resistant brick or castable refractory walls and also is divided by an interior arched wall of like material separating lower primary and upper secondary horizontally extending

interior chambers

30 and 32 respectively, with the refractory material facing inwardly on all sides of both chambers permitting substantial heat or flame to be applied to the generated gases flowing therewithin.

Lower wall 16 is preferably suitably supported upwardly by means of beams 22.

The generally vertically extending walls 10, are slightly canted as shown so as to exploit the forces of gravity to retain the refractory material in its original preset position, and to overcome any tendency tobulge as often found in walls disposed completely vertically. Since great temperature variations can be reasonably anticipated, the refractory walls would move by thermal expansion and contraction.

The construction may be of varying shapes and forms, although the outer shell or housing is desirably made of such as hot roll plated steel or boiler plate construction.

Primary chamber 30 serves as the ignition chamber and secondary chamber 32 serves as the combustion or after burner chamber.

Front (entrance) wall 12 is apertured to allow provision of.a charging door or doors or equivalent closure mechanism 34 and rear exit wall 19 correspondingly apertured to allow provision of a cleanout or dumping door or doors or closure mechanism 36, which doors are each formed of an outboard metallic shell and inboard refractory material and shaped and constructed so as to close the respective material receiving or material discharging opening in the respective front or rear walls and to be openable or closeable at the operators will.

Means for loading or charging the incinerator with material .to be incinerated is designated by 50 and includes a supporting frame structure comprised of a generally rectangular-shaped supporting frame member positioned upwardly as by legs so as to lie adjacent the entry or charge end of the apparatus. Correspondingly, a receiving table 52 may be positioned adjacent the discharge end.

A loading hopper 60 may be movably mounted upon loading beams 50 for loading same with the material to be incinerated before being motivated into the incinerator and eventually therefrom onto receiving table 52.

Broadly, the combustible material is burned in primary chamber 30 and effluent flows inwardly or away from the entry or charge end as indicated by arrows a and upwardly through suitable breachings or openings 39 in arched intermediate wall 42 separating the primary and secondary chambers, from which secondary chamber it flows outwardly or toward the entry or charge end as indicated by arrows b.

That is, the arched intermediate wall 42 serves as a heat conductor, completely traversing the interior of the housing and extending between and being secured to the opposed refractory walls at each side of the housing interior, and being suitably apertured so that the ignition and afterburner chambers are in communicating relation with respect to each other.

It will be noted that the bottom wall of the housing interior is disposed in sloping relationship to the primary combustion chamber to allow drainage of any liquid materials or coolants which may be fed to the primary chamber or any liquid melting materials where the incinerated material is a metal downwardly toward a drain 44 for ready removal therefrom.

Primary ignition chamber 30 is provided with a primary ignition burner device, diagrammatically represented by 64 and shown as located in a side wall 10 and connected in communicating relation to a gas fuel supply line and a combustion air supply line, neither being shown as same do not form part of the invention.

Primary ignition burner device 64 includes the usual pilot tip mechanism nozzle type flame mechanism and ignition mechanism so as to define a burner device capable of a wide range of adjustment with respect to rich, lean or correct air/gas ratio so as to promote a high efficient combustion within the primary chamber.

The flame from the burner device will impinge the surfaces of the material to be incinerated as well as the surfaces of the walls of the primary ignition chamber.

Additionally, a plurality of spaced forced primary air inlets 46 may be provided in the bottom wall of the primary ignition chamber for purposes of charging pressurized air thereinto and aiding in the promotion of the ignition process.

The gases in passing from the primary to secondary chambers follow a sinuous or tortuous course which aids in the acceleration of their velocity before they are discharged through an outlet in the upper forward wall 12a spaced inboard of lower forward wall 12.

i The sinuous configuration of the flow passage indicated by the generally horizontal flow through the primary chamber, generally vertical flow upwardly into the secondary chamber, and generally horizontal flow through the secondary chamber serves to permit an intimate mixing of the combustion air with unburned gases so that substantially complete combustion of the unoxidized gases is achieved.

The afterburner chamber is provided with one or more afterburner devices 74 extended through one of side walls 10 and constituting blower means for feeding combustion air thereinto.

The afterburner devices are positioned within the afterburner chamber somewhat adjacent openings 40 in intermediate wall 42.

Openings 40 are located in relation to the afterburner devices 74 so as to offer a complete mixing of the combustion air with the smoke so as to obtain complete burning early within the secondary chamber, that is immediately such smoke is passed thereto from the primary chamber through breachings 39.

Temperature sensor mechanism and 82 are suitably disposed within primary and

secondary chambers

30 and 32 respectively for assuring efficient combustion by way of primary ignition burner devices 64, forced primary air inlets 46, and afterburner devices 74.

Additionally, pressure sensor mechanisms may be provided so as to be responsive to changes in air pressure within the primary and secondary chambers for controlling the supply of air to the primary ignition burner devices and afterburner devices, the mechanisms being connected by suitable means in conventional manner to control motors which are operatively connected to control valves disposed in flowcontrolling relation with respect to the air conduits, and being operative in response to changes in pressure so as to cause the motors to be energized and the control valves to be moved between opened and closed positions.

Thus the amount of air and gas which is supplied to the chambers may be variously and selectively adjusted.

The oxidized and combusted gases are discharged through discharge outlet 70 of the secondary chamber into communicating inlet 86 of a horizontally disposed generally elongate rectangular exhaust connector structure 88 preferably constructed of metal or the like.

The exhaust connector structure has an outlet adjacent an outer end portion which is connected in communicating relation to the intake flange 90 of a scrubber generally indicated by 92 which is disposed generally adjacent the incinerator and comprises preferentially a rectangular housing within which are disposed vertically extending first and second

water wash zones

102 and 104 respectively which are interconnected at their lowermost regions by an opening 106 therebetween.

The gases first pass into a portion of the scrubber constituting primary water wash zone 102 for the washing and cooling of the hot exhaust gases and which results in some of the noxious gases being absorbed by a first water jet 108 situated at the top of the vertically extending passage defining the primary water wash section and dispersed upon the gases as they are directed downwardly in the direction of the arrows c.

The gases are then passed vertically upwardly through second water wash zone 104 in the direction of the arrows d and past a second water jet as well as past a horizontally disposed elongate undulating moisture eliminating member 112 affixed to opposite wall surfaces and each presenting alternately smoothing arcuate inwardly facing concave and convex surfaces, so that the scrubbed gases may be passed through an opening 114 in the lower wall 120 of an exhaust fan housing 122 in which is disposed an exhauster 124 which is given its rotational movement by a motor 126 through suitable device means such as a drive belt 128 trained around a pulley 130 keyed to the end of the motor output shaft and another pulley 132 keyed to the shaft of the exhauster.

lt will thus be seen that when the motor is energized, the fan will be driven to exhaust the gases from the afterburner chamber.

The gases are then passed outwardly through an opening 136 in one vertical wall of the exhaust fan housing past an automatic bypass 140 and outwardly thereof through a passage 144 to a stack generally indicated by 150.

Means are provided for counter balancing automatic bypass 140 including a counter balance weight 142 on the opposite side of a pivoted connection 148.

The lower end of the exhaust structure is provided with a basket or sump 156, for the collection of the water which will contain varying concentrations of absorbed gases, which basket may be removable.

It will therefore be seen that the exhaust structure not only serves to remove a substantial quantity of the noxious gases but also cools the exhaust gases to thereby obviate the need of a relatively large stack structure.

I claim:

1. The method of recovering copper from copper wire having a carbonaceous insulating covering in an incinerator with a minimum of fuel comsumption comprising the steps: causing the combustion of the insulating covering from a mass of the wire in a first-in-time ignition period under conditions of low temperature and controlled atmosphere precluding the promotion of metal oxidation, charging the generated hot gaseous products of combustion through an afterburner in a second-in-time combustion period for exploiting the heat generated in the ignition chamber for maintaining the temperature of the secondary chamber at a predeter mined operating temperature level and under a controlled ratio of the levels of gaseous products and make up air for the consumption of the suspended volatile combustible materials.

2. The method of recovering copper from copper wire having a carbonaceous insulating covering in an incinerator with a minimum of fuel consumption comprising the steps: causing the combustion of the insulating covering from a mass of the wire in a first-intime ignition period under conditions of low temperature and controlled atmosphere precluding the promotion of metal oxidation, charging the generated hot gaseous products of combustion through an afterburner in a second-in-time combustion period for exploiting the heat generated in the ignition chamber for maintaining the temperature of the secondary chamber at a predetermined operating temperature level and under a controlled ratio of the levels of gaseous products and make up air for the consumption of the suspended volatile combustible materials, and charging the so-burned exhaust gases through a scrubber for additional cleansing of any particulate components therefrom prior to release to atmosphere.

Claims

1. The method of recovering copper from copper wire having a carbonaceous insulating covering in an incinerator with a minimum of fuel comsumption comprising the steps: causing the combustion of the insulating covering from a mass of the wire in a first-intime ignition period under conditions of low temperature and controlled atmosphere precluding the promotion of metal oxidation, charging the generated hot gaseous products of combustion through an afterburner in a second-in-time combustion period for exploiting the heat generated in the ignition chamber for maintaining the temperature of the secondary chamber at a predetermined operating temperature level and under a controlled ratio of the levels of gaseous products and make up air for the consumption of the suspended volatile combustible materials.

2. The method of recovering copper from copper wire having a carbonaceous insulating covering in an incinerator with a minimum of fuel consumption comprising the steps: causing the combustion of the insulating covering from a mass of the wire in a first-in-time ignition period under conditions of low temperature and controlled atmosphere precluding the promotion of metal oxidation, charging the generated hot gaseous products of combustion through an afterburner in a second-in-time combustion period for exploiting the heat generated in the ignition chamber for maintaining the temperature of the secondary chamber at a predetermined operating temperature level and under a controlled ratio of the levels of gaseous products and make up air for the consumption of the suspended volatile combustible materials, and charging the so-burned exhaust gases through a scrubber for additional cleansing of any particulate components therefrom prior to release to atmosphere.