JPH07117223B2 - Method and apparatus for forming harmless aggregates using hazardous waste - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for forming harmless aggregates from hazardous wastes by thermally induced oxidation.

Many industrial processes produce by-products and waste materials that cannot be legally disposed of without some form of storage or treatment. Efforts to dispose of such materials in containment vessels in the past have been inadequate due to lack of attention to the manufacture of such containment vessels or deterioration of these vessels have resulted in spills or spills of hazardous waste. I knew it was. Other means of treating hazardous waste include injection of such materials into wells, but such materials naturally enter into the aquifer below which they are injected. It may not be stationary in the terminating strata.

In addition to the technical issues associated with such disposal methods, there remains potential liability for anyone using such benefits. Years after the substance is deposited on the waste site, the claim for liability bears the sole responsibility of the parties to locate the hazardous substance within the approved waste disposal site and the disposal site has failed solely to prevent waste clutter. , Can be generated based on the recognition that. Such problems have led to the quest for means to use hazardous waste in manufacturing processes that eliminates its harmful properties and produces a product that is suitable for use by the general public and for use by the general public. It was One of the approaches attempted has been to oxidize the material by passing it through various types of heaters under oxidizing conditions. One such variant of such treatment uses a counter-current rotary kiln to induce combustion of combustible components in hazardous waste and sell non-combustible materials as a valuable and useful product on the market. The aggregate that could be done.

Efforts at individual methods of waste use have been partially successful in producing products that will pass the appropriate EPA regulations related to waste disposal. However, these processes have important drawbacks. The most important drawback associated with the use of hazardous waste in rotary kilns or the like is the generation of additional non-combustible substances that cannot be formed into aggregate and must be disposed of as hazardous waste. Is. Therefore, even if the amount of hazardous waste is greatly reduced by this treatment, the problem of discarding part of the material treated as hazardous waste still remains. The most common treatment also produces large amounts of contaminated scrubber water that must be treated and discarded.

Therefore, one of the objects of the present invention is to provide a method and apparatus for using hazardous waste substances as recyclable substances in the manufacturing process, to render only the products of such treatment harmless and treated. It is to be able to be sold for use by the general public regardless of the nature of the input material.

Another object of the invention is to convert harmful solid substances into harmless non-active aggregates which can be sold without limitation.

Another object of the present invention is an economy in which any solid resulting from the use of hazardous waste liquids as a fuel and fuel supplement instead of natural gas or coal can be sold to the general public regardless of the harmful nature of the input material. To make it available in a specific way.

An additional object of the present invention is to provide a system for the utilization of large scale hazardous waste materials that can be economically operated without significant risk to personnel operating the system. These and other objects of the invention include:
It may be more fully described herein, or may be apparent from practice of the invention.

SUMMARY OF THE INVENTION To achieve these and other objects of the invention, a process is provided for converting hazardous waste into harmless aggregate. The process involves disposing a source of solid waste material consisting of large solid waste and waste particulates. These substances are classified and large solid wastes are guided to a rotary kiln with an inlet section, a combustion section and an outlet section. The operating conditions in the kiln are controlled so that large solid waste forms solid granular primary aggregate, clinker and gaseous combustion by-products. Most volatile combustibles in large solid waste are volatilized at the entrance of the kiln. Gaseous by-products from the kiln are sucked out of the kiln and discharged by ventilation. Waste particulates separated from solid waste are directed to the oxidizing means along with combustible materials. Combustion in the oxidizing means causes the waste particles to be converted into non-combustible particles, molten slag and waste gas. The temperature of the oxidizing means is preferably controlled in the range of 1800 ° F to 3000 ° F. Non-combustible fine particles and waste gas are sucked out from there and discharged by ventilation. Non-combustible particulates, gaseous by-products and waste gases are cooled and non-combustible particulates are separated from combustion products and waste gases. The solid granular primary aggregate and non-combustible particulates are reintroduced into the oxidizing means. The heat from the oxidizing means is transferred onto the non-combustible particulates and primary aggregate to create molten slag. The molten slag is cooled to become harmless aggregate. When the primary aggregate and the non-combustible fine particles are introduced into the oxidizing means, it is preferable to introduce them into the oxidizing means in individual batches. Furthermore, it is preferred that when these substances are introduced into the oxidizing means they are introduced in the form of a pile so that the heat from the oxidizing means is transferred above the deposition surface. Further, the rotary kiln is preferably operated at an average internal temperature in the range of 1600 ° F to 2300 ° F.

A preferred apparatus for embodying the method of the present invention for converting hazardous waste into harmless aggregate comprises a rotary kiln with an inlet section and an outlet end. The oxidizing means is adjacent to the entrance of the kiln. A source of solid waste material including large solid waste and waste particulates is also arranged. Means for separating large solid waste from waste particulates is included, just as it is included for guiding large solid waste to the inlet section of a rotary kiln. The apparatus also includes means for inducing combustion in the kiln to convert large solid waste into solid particulate primary aggregate, clinker, volatile gases and gaseous combustion byproducts. The means are used to separate the clinker from the solid granular primary aggregate. The apparatus further comprises means for discharging gaseous combustion byproducts from the kiln and the oxidizing means. The means includes inducing combustion in the oxidizing means to convert waste particulates, volatile gases and gaseous combustion byproducts into non-combustible particulates, molten slag and waste gases. The cooling means cools the noncombustible particles in the waste gas, and the separating means separates the noncombustible particles from the waste gas.
The apparatus further comprises means for inducing solid granular primary aggregate and reinducing solid non-combustible particulates in the molten slag to produce a fully molten mixture. This means comprises means for cooling the fully melted mixture to make a harmless aggregate. Preferably, the oxidizing means comprises a plurality of refractory lined vessels in communication with the inlet of the rotary kiln.

The invention will now be disclosed in the preferred embodiment section.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings, which form a part of the specification, depict embodiments of the invention.

FIG. 1 is a schematic view of an embodiment of the present invention.

FIG. 2 is a schematic partial sectional view of the oxidizing means of the embodiment of FIG.

FIG. 3 is a schematic diagram of an embodiment for the assembling particulate material being guided to the oxidizing means of the embodiment of FIGS. 1 and 2.

Description of the Preferred Embodiment An embodiment of the present invention is depicted schematically in FIG.

The present invention is a device for converting hazardous waste to harmless aggregates and a process of operating the device to perform this function.
According to the present invention, a rotary kiln having an inlet portion and an outlet portion is arranged. The rotary kiln 10 includes an inlet portion 12 and an outlet portion 14 as specifically illustrated and depicted in FIG. Combustion part between the inlet and outlet parts of the rotary kiln
There are 16. In the depicted embodiment, the boundaries of each part are common terminals, and the three parts of the rotary kiln are merely illustrative and can overlap. It should be said that some combustion can occur at the inlet section 12 or the outlet section 14, but combustion originally occurs at the combustion section 16 of the kiln 10.

The kiln schematically depicted in Figure 1 is a standard countercurrent rotary kiln constructed for treating limestone or shells to produce quicklime. It has a metal outer shell lined with refractory bricks. The composition of refractory bricks is determined by the operating temperature and the materials passed through the rotary kiln. In this example, the rotary kiln is designed to work in the temperature range of 1600 ° F to 2300 ° F, and in this example, a 70% alumina refractory brick made by National Refractory of Oakland, California has a premature heat resistance. It has been used without deterioration. The rotary kiln is supported by a normal bearing support (not shown), and is 1 to 1 by a normal kiln driving means (not shown).
Driven at drive speeds in the range of 75RPH.

As will be discussed in more detail below, solids are guided to the entrance 12 of the rotary kiln 10. As the kiln rotates, material larger than about 50 microns moves through the combustion section 16 towards the outlet section 14, while smaller material is carried over the larger solid material by the flowing gas stream. In the depicted embodiment, rotary kiln 10 includes a cooling chamber 18 at the exit of the kiln. The cooling chamber receives the solid material through the section leading to the rotary kiln. The chamber receives the larger solid material which is transferred by rotation to the outlet drop trough 20 where the solid material exits there from the rotary kiln outlet. Further, a fuel source 22 and an air source 24 for supporting combustion in the rotary kiln 10 are connected to the rotary kiln 10. The fuel used can be a combustible waste liquid, a combustible liquid fuel or a combustible liquid or gas, including combustible natural gas. Moisture in oxygen or compounds is used to control temperature and combustion. The mixture of air and fuel is at the outlet section 14 with the gas flowing in the kiln 10 towards the inlet section 12 countercurrent to the larger solids which are being directed towards the outlet section by the rotation of the kiln. Guided to the rotary kiln 10. As mentioned earlier, smaller particles are introduced into the gas flowing through the kiln where they are separated from the larger solids and discharged from the kiln. According to the invention, the device with the oxidizing means is adjacent to the entrance part of the kiln. As embodied here, the device comprises a twenty-first oxidizer 26. As shown in FIG. 1, the first oxidizer 26 is adjacent to the inlet section 12 of the rotary kiln. The oxidizer 26 is in communication with the inlet section 12 of the rotary kiln 10 and receives the volatile gases vaporized from the materials introduced into the rotary kiln along with the combustion byproducts from the combustion taking place in the rotary kiln. A source of waste material directs the material to the inlet portion 12 of the kiln 10 where the countercurrent gas flow separates larger particles (solid waste material) and smaller particles (waste particles). In accordance with the present invention, solid waste materials include large solid waste and waste particulates. For purposes of this invention, large solid waste is waste having a particle size greater than about 50 microns, while any waste particulate is defined as material having a particle size less than 50 microns. This device can operate with materials separated into a particular size, but with larger materials that are kiln-induced to be classified as either non-combustible materials, volatile gases or combustion by-products during passage through the rotary kiln. It is the purpose of the separation to provide the first oxidizer 26 with material rather than being able to be easily oxidized or melted in its physical state.

In accordance with the present invention, there are means provided for separating large solid waste from waste particulates. As embodied herein and depicted in FIG. 1, the apparatus includes a passive conveyor 30 that receives material from a waste source 28 and directs waste generated fuel to an inlet section 12 of a rotary kiln 10. Sorting large solid waste from waste particles is occurring throughout the rotary kiln 10. It should also be noted that solid waste can also be sized by size prior to introduction into the kiln, where the waste particulates can be directed directly to the oxidative means.

According to the invention, the device also comprises means for inducing combustion in the kiln converting large solid wastes into solid granular primary aggregate, clinker, volatile gases and gaseous combustion by-products. As embodied herein and depicted in FIG. 1, the means for inducing this combustion comprises a combustion source 22, an oxygen source 24 and a rotary kiln 10. As disclosed below, the operating conditions in the kiln are such that large solid waste is first converted to granular primary aggregates, volatile gases and gaseous combustion byproducts with a minimal amount of clinker produced by the rotary kiln. To do so. Operation of the rotary kiln 10 passes solids through a cooling chamber 18 to an outlet drop trough 20 toward the exit 14 of the rotary kiln. As embodied here, the solid material in the outlet drop trough 20 is sent to the kiln classifier 34. The kiln classifier 34 may be any conventional mechanical device that separates large solid particles from fine solid particles.
As embodied herein, any solid material with a diameter of 3/8 inch or greater is classified as something of a clinker that is inferior to the primary aggregate. The clinker and particles are passed over the magnetic separator 32. The primary aggregate is passed over another magnetic separator 32A. The ferrous metal is removed and sent to the metal yard for sale as scrap steel.

In accordance with the present invention, there is provided means for inducing combustion in the oxidizing means to convert waste material particulates, volatile gases and gaseous combustion byproducts into non-combustible particulates, molten slag and waste gas. As embodied herein, the means for inducing combustion within the oxidizing means is a source of oxidizer fuel.
And a source of oxygen. In this way, the oxidizer 26 provides waste particulates and volatile gases from the rotary kiln 10, which may be combustible or non-combustible, combustion byproducts from the rotary kiln 10, fuel from the fuel source 36 and oxygen source 38. Receive oxygen from. In the present embodiment, the first oxidizer 26 is from 1800 ° F. to 30 °
Works in the temperature range up to 00 ° F. In oxidizing environments, first
The combustible material in the oxidizer 26 is converted to waste gas and non-combustible particulates. The non-combustible particles may or may not be melted depending on their composition.

As shown schematically in FIG. 2, some of the non-combustible particulates are melted and in the form of a liquid slug 40 a first oxidizer.
Collected at the bottom of 26. In FIG. 2, the liquid slug is shown to be discharged from the device by slug port 42. Such a slug port is the first oxidizer
It can be selectively positioned along the bottom of 26. As shown in FIG. 2, the slug port 42 is associated with a burner 44 positioned to hold the material in the vicinity of the slug port 42 in a molten state. Oxidizer
For purposes of raising the temperature at various locations within 26, the system may optionally include burners directed directly into the first oxidizer 26.

As illustrated in FIG. 2, the first oxidizer 26 is a rotary kiln 10
A refractory lined container in communication with the inlet portion 12 of the. The first oxidizer of this embodiment has a rectangular cross section and comprises an internal refractory lined metal shell 46. The refractory lining of the depicted embodiment is a refractory lining 50 that is integral with the refractory brick 48.
And. In the depicted example, the refractory brick is 70% alumina from National Refractoyr, Inc. of Oakland, California. The monolithic lining is a Jade Pak made by AP Green of Mexico City, Missouri. In this embodiment, the refractory brick at the bottom of the first oxidizer 26 is the first oxidizer.
It is much thicker than the refractory bricks of the 26 wall section. this is,
It is based on the operating temperature at that portion of the oxidizer caused by the flowing liquid slug 40 which transfers heat from the hot gas passing through the interior portion 52 of the oxidizer. Another preferred embodiment of the first oxidizer has a water cooled ceiling, water cooled metal walls and a refractory floor. Such a structure allows higher operating temperatures.

In the embodiment of FIG. 2, the hot gas is passed through the first oxidizer 26
90 ° towards conduit 54 which connects to the oxidizer 56 of the.
The structure of the second oxidizer 56 is similar in some respects to that of the first oxidizer. However, in the embodiment shown, the second oxidizer 56 has an interior 58 that is also cylindrical.
It is also cylindrical. Gas and particulates are the first oxidizer
From 26 through conduit 54 towards a second oxidizer 56. The structure of the conduit 54 and the second oxidizer 56 is similar to the structure of the first oxidizer of the embodiment depicted in that they consist of refractory lined steel. The refractory material used in conduit 54 is JadePak, and the second oxidizer 5
The refractory material used in 6 is Jade Pak. First oxidizer
Similar to 26, the second oxidizer 56 also comprises multiple layers of refractory brick in its bottom portion. The function of this multi-layer refractory material is discussed above.

In the depicted example, all combustion of waste material is first
It does not occur in the oxidizer 26 of the. A significant portion also occurs in the second oxidizer 56. Therefore, in the operation of the embodiment shown in FIG.
From the inner portion 52 of the second oxidizer 56 into the inner portion 58 of the second oxidizer 56.

In the preferred embodiment, liquid is now injected into the second oxidizer 56, as embodied by the liquid inlet 60.
The liquid source for the liquid inlet 60 in this embodiment comprises a sump system (not shown) that surrounds the entire device. Any liquid, including waste derived fuel, rainwater or contaminated rainwater, is controlled by the sump system and injected through the liquid inlet 60 into the second oxidizer 56. The entire system therefore has means for using the waste derived fuel and contaminated water surrounding the system within the system itself. Those skilled in the art to which the present invention pertains can readily design drainage and sump systems such that the present invention can be operated without the specific description of such systems.

According to the present invention, means are provided for cooling non-combustible particulates and waste gas. A cooling vessel 62 is provided here, as is schematically embodied and depicted in FIG. The cooling container 62 has a water inlet 64. In this embodiment, the water inlet 64 has a nozzle (not shown) for introducing water and air at a speed higher than the speed of sound. The spray nozzle of this example is a Soni, NJ
It is an SC CNR-03-F-02 model "sonic" manufactured by company c.
A water source 66 is in communication with the water inlet. In this embodiment, the water source 66 supplies waste-free water. The function of the water from the water source 66 is to reduce waste gas and incombustible particulates to almost 350
Since it is allowed to cool to a temperature in the range of ° F to 400 ° F, the gas and particulate matter can be separated by conventional separation means described below. First
As is schematically embodied and depicted in the figure, there is a source of alkaline material in communication with a spray nozzle 70 for introducing an alkaline liquid as a spray into a dry spray reaction vessel 62. The function of the spray injection of the alkaline substance is to neutralize any acid in the waste gas.

According to the present invention, the apparatus comprises means for passing gaseous combustion byproducts from the kiln and waste gas from the oxidizer means. As embodied here, there is a second oxidizer 56
Between the connector and the dry spray reactor 62
72 are equipped. This connector has a structure similar to that of the second oxidizer 56, namely a structure consisting of a refractory lined metal shell. Similarly, the dry spray reactor 62 is also a refractory lined metal container.

When making connections between the various elements of the invention, the effects of differential thermal expansion must be considered. Because oxidizers 26 and 5
6, because the temperature of the material in conduit 54 and connector 72 is very high. Moreover, because of the significant temperature differences in the different parts of the device, adjustments at the tethers between such parts must be made for expansion and contraction.

The system is operated below atmospheric pressure, as described below. Thus, any leaks in the tethers between parts of the device will not be detrimental to the performance of the device, unless the leak rate is so great as to adversely affect the combustion of the material in the oxidizer. This requirement is less important in other parts of the system that operate at lower temperatures.

According to the invention, the device comprises means for separating the non-combustible particulates and the waste gas. Embodied here and first
As schematically depicted in the figure, the device comprises two filter systems working in parallel, each having a filter 74 and a fan 76. Since the waste gas and particulates are preferably introduced into the filter at temperatures above 350 ° F and below 400 ° F, conventional baghouse filters can be used. The operation of this example determines that a conventional Teflon (polytetrafluoroethylene) filter element can be used in connection with this operation. The waste gas is separated from the non-combustible particulates and the waste gas is passed by a monitoring means 78 which monitors the composition and temperature of the waste gas. The waste gas is then passed through the chimney 80 into the atmosphere. The fan 76 sucks through the entire device for sucking volatile gases and combustion byproducts from the rotary kiln. Since the combustion byproducts from the rotary kiln, the combustion byproducts from the oxidizer, and all gas passing through the system pass through fan 76, the entire system operates below atmospheric pressure. The particulates accumulated in the filter 74 are passed by the pump means 82 to the accumulator 84. Similarly, the primary aggregate is pumped through pump 86 and into accumulator 84. A preferred embodiment of accumulator 84 is depicted in FIG.

In accordance with the present invention, the apparatus is provided with means for inducing solid granular primary aggregate and reinducing non-combustible particulates into a fully melted mixture. As embodied herein and depicted in FIGS. 1 and 2, the device comprises means for directing the non-combustible particulates and primary aggregate to the oxidizer means, and in particular the second oxidizer 56. As depicted in FIG. 3, accumulator 84 includes a first inlet 88 arranged to receive particulates from pump 82. accumulator
84 further comprises a second inlet 90 arranged to receive the primary aggregate through pump 86. A first sensor 92 for detecting the desired maximum level of particulate matter in accumulator 84 is associated with the preferred embodiment of accumulator 84. The second sensor 94 is the accumulator 84
The level of particulate matter therein is detected, and the valve control means 100 operates the valve 98 by the sensor control mechanism. During operation of the device, inlets 88 and 90 introduce particulate matter into accumulator 84 where particulate matter is located above sensor 92.
Accumulated up to a predetermined level so that
The valve 98 is opened by the control sensor control means 96 and the valve control 100, which allows particulate matter to be routed through the conduit 102 and into the second oxidizer 56 as shown in FIG. If the level of particulate material in accumulator 84 reaches the level of sensor 94 below, sensor control and valve control 100 closes valve 98, thereby interrupting the flow of particulate material through conduit 102.

Although the conduit 102 has been shown to direct solid particulate matter into the second oxidizer 56, the solid particulate matter does not.
Alternatively, it can be directed into both the first and second oxidizers. As shown in FIG. 2, the solid particulate matter directed to the second oxidizer by conduit 102 falls into the central portion 58 of the second oxidizer 56 and forms a deposit on the bottom. To do. The heat from the gas passing through the second oxidizer 56 is transferred to the surface of the deposit of particulate matter which melts the portion of the particulate matter having a melting point lower than the temperature of the gas hitting the surface. Material flows from deposit 104, which carries any particulate material that is not melted therein, and slug port 4
It joins the molten slug 40 flowing from 2.

According to the invention, the device comprises means for cooling the substantially molten mixture to form a harmless aggregate. As embodied herein, the apparatus comprises cooling means 106 schematically depicted in FIG. In the preferred embodiment, the cooling means simply comprises water into which the substantially molten mixture is discharged. The cooling means takes heat from the molten mixture and forms harmless aggregate.

Operation of the apparatus described above will now be described with respect to a method for using hazardous waste in a manufacturing process to form harmless aggregate. According to the invention, the first step in the process is to provide a source of solid waste material consisting of large solid waste and waste particulates. In embodiments of the present invention, waste is sent to the device in various forms. Wastes include contaminated topsoil, contaminated building rubble, semi-solid sludge from wastewater treatment operations, metal drums of liquid waste, fiber drums containing liquid or solids (usually lab packs).
ck))). When the waste material is sludge containing morphology, the waste is first passed over a shaker screen and the liquid separated and introduced into the apparatus of the invention separately from the solid residue. When the waste is in a 55 gallon metal drum, the drum is chopped and introduced into the rotary kiln as part of a larger solid waste, thereby eliminating the need for drum cleaning or inspection. . It may also be necessary to chop the input material multiple times to obtain an input material that is effectively consumed in the process.

In controlling the process and controlling the operating temperatures of the various components that carry out the process, it is advantageous to know certain characteristics of the input material so that the feed rate of waste material and other input materials introduced into the device is controlled. Desired operating conditions can be obtained. It is preferred that the waste material appears with the statement that it will include BTU and water content. However, there is also a need to test the BTU content and other properties of the input material to facilitate operation of the device. While a load of waste material can have one value for the total BTU amount, in many cases waste material is heterogeneous and therefore the operation and control of the equipment requires some interference and combustible composition of waste. It is noteworthy to prevent operating parameters from deviating from the need for complete oxidation of the element and formation of the desired harmless aggregate.

Furthermore, in addition to BTU and water content, it is also advantageous to know the acid content, ash content and halogen concentration. The acid content of the waste product provides the operator with a means of assessing how much alkaline agent is consumed in the process, which strongly affects both the operation of the process and its economics. The amount of ash in the waste determines how much aggregate is produced. The content of halogen affects the operation of the process,
And it is preferably in the range of 10 to 15%.
Economically producing the desired aggregates by testing these properties of the waste and appropriately controlling the input of water, auxiliary fuels, oxygen, alkaline agents, coolants and the like to obtain the desired operating conditions. Can be manufactured.

The process according to the invention comprises the step of separating large solid wastes from particulates, which separation, as described above, can be generated in a rotary kiln 10 or simply sized wastes to different locations of the device. Can be achieved by turning to. For example, if the waste particulates are contaminated topsoil, they can be directly directed to oxidizing means.

According to the invention, the process comprises the step of directing large solid waste into a rotary kiln having an input section, a combustion section and an outlet section. The operating conditions in the kiln are as follows: Large solid waste is combusted, and solid granular primary aggregate, clinker, and large amount of volatile combustible substances in the large solid waste volatilized at the input part of the kiln. Combusted to form a gaseous combustion by-product with a portion. Rotary kiln is about 1600 ° F to 2300
It is preferably operated at an average internal temperature in the range of ° F.

It should be noted that there is a considerable temperature gradient in the kiln along its length and in the radial direction. Therefore, the kiln portion can deviate significantly from the 1600 ° F to 2300 ° F range.

Large solid waste is guided into a rotary kiln, the rate of which depends on the amount of BTU, but is usually about 20 tons per hour. Since the kiln is rotated at speeds in the range of 1 to 75 RPH, the total residence time of the solid material present in the kiln at the outlet section 14 is in the range of about 90 to 120 minutes.

With these operating parameters, the rotary kiln produces a solid output consisting mainly of solid granular primary aggregate with a small amount of material that can be classified as a clinker. For the purposes of the present invention, clinker is typically a large size solid, such as an unreacted building brick passing through a rotary kiln or an agglomerate of low melting point material that has been melted and agglomerated at relatively low temperatures in a rotary kiln. is there. The operating conditions of the rotary kiln are controlled to facilitate two conditions.

The first is to convert most of the large solid waste into solid granular primary aggregate, and the second is to volatilize most of the volatile combustibles in the large solid waste in the input part of the rotary kiln. It is to let. As will be discussed below, the primary aggregate is recycled into the process of being melted and directed into the molten slag within the oxidizing means. Since slugs are formed into harmless aggregate, it is desirable that as much of the treated material as possible be transformed into its shape. The substances that form the clinker output from the kiln are tested to determine if they are harmful substances that can leach from them.
Any substance with leachable harmful substances is redirected at the input into the rotary kiln. The operation and process of the device results in a very small amount of output from the rotary kiln, which is classified as a clinker material.

A second purpose in operating a rotary kiln is to volatilize most of the volatile combustible material within the input section of the rotary kiln. This reduces the amount of BTU of solid material passing through the rotary kiln and into the combustion section 16 of the rotary kiln. If rotary kiln 10
If the BTU content of the solid portion reaching the combustion portion 16 of the is too high, uncontrolled combustion can occur in the combustion portion of the kiln. Therefore, the operating conditions of a rotary kiln should have a temperature at the input that is very sufficient to volatilize most of the volatile components in the large solid waste that is directed to the kiln.

The solid material exiting the outlet trough 20 is sent to a kiln classifier 34, as shown schematically in FIG. The classifier 34 may be any conventional mechanism for separating large solid particles from solid particles. As embodied here, 3 /
Any solid material with a diameter greater than 8 inches is classified as a clinker of something smaller than the primary aggregate. The clinker and particles pass over the magnetic classifier 32. The primary aggregate passes over another magnetic classifier 32A. The ferrous metal is separated and sent to a metal depot for sale as scrap steel.

According to the invention, the gaseous combustion by-products from the kiln are drawn from it by draft air. As mentioned above, the fan 76 maintains the entire system below atmospheric pressure and draws gas from the rotary kiln as well from the oxidizer throughout the system.

According to the present invention, the process comprises directing the waste particulates to an oxidizing means. As embodied herein, waste particulates from the rotary kiln 10 are entrained in the gas stream and carried into the oxidizer 26.

According to the invention, flammable substances are introduced into the oxidizing means. As embodied herein, there is a source of liquid fuel 36 coupled to the first oxidizer 26. Inputs for fuel, waste particulates, volatile gases from solid waste materials in the kiln, and oxygen injection should all be in the range of about 1800 ° F to 3000 ° F for the temperature in the first oxidizer. Used for control. The temperature of the input material, including any derived auxiliary fuel,
Determined by BTU amount. The supplemental fuel from fuel source 36 preferably comprises combustible liquid waste material. It is further preferred that the flammable liquid waste material comprises a liquid that is either organic solvent to drilling mud waste or paint.

According to the invention, the process comprises the step of inducing combustion in the oxidizing means to convert waste particles into non-combustible particles, molten slag and waste gas. As embodied herein, the oxidizer means comprises two oxidizers, a first oxidizer.
26 and a second oxidizer 56. In the first oxidizer 26, most of the combustible material is oxidized to form gaseous combustion byproducts. These pass through the interior 52 of the first oxidizer 26,
It is sucked out through the conduit 54 into the interior 58 of the second oxidizer 56. Operating temperatures of 1800 ° F to 3000 ° F are preferred, with some of the solid material melted. This material is collected in the bottom portion of the first oxidizer as liquid slug 40, as shown in FIG. 2, and flows toward slug port 42.
The solid particulate matter, which has not yet been melted, travels with the gaseous combustion by-products through conduit 44 into the interior of oxidizer 56, where a portion thereof can be melted in second oxidizer 56 or remain unmelted. It is also possible to pass through the device as solid granular waste at.

According to the invention, the solid granular primary aggregate and non-combustible particulates are introduced into the oxidizing means. Embodied here and second
As clearly depicted in the figure, the conduit 102 directs primary aggregate and solid particulate into the interior of the second oxidizer 56. 1
Desirably, the secondary aggregate and solid particulates are derived in individual batches. Continued induction of these materials into the oxidizer cools the surface of the particulate matter deposits within the oxidizer to prevent surface melting. This inhibits the oxidizer-induced melting of the particulate matter, and thereby the production of molten slag that forms harmless aggregates.

As shown schematically in FIG. 2, individual batches of primary aggregate and non-combustible particulates were directed to a second oxidizer,
It is desirable to form a deposit in the oxidizer. The heat from the oxidizing means is transferred to the surface of the deposit, where the material with the relatively low melting point is melted and flows down to the bottom of the oxidizer, towards the conduit 54, where the molten material slags. Exit port 42. The process can generate slag-like aggregates or non-combustible particulates having a melting point higher than the temperature of the second oxidizer. Therefore, such particulate matter is not melted. However, it is forced into the molten material formed in the second oxidizer and into the slug, forming a nearly molten mixture. By melting the surface of the deposit and into the molten mass and solid particulate matter flowed therein, conduit 54
By allowing it to flow toward, this exposes a new surface on the particulate material, which is melted and flows out of the device through the slug port. The example shown here is a secondary aggregate of primary aggregate and non-combustible particulate matter.
, But the process is also operable if a portion of the material is directed to the first oxidizer. It is also possible to inject the primary aggregate into both oxidizers or the particles into both oxidizers individually, but to combine the granular primary aggregate with non-combustible particles and to combine them. It is preferable to re-induce during the process.

The embodiment of FIG. 2 also shows an apparatus for injecting oxygen into the first oxidizer. The process is also operable to inject oxygen into the second oxidizer. During the preferred operation of the system, the average temperature in the first oxidizer is approximately 3000 ° F. The temperature in the conduit between the first oxidizer and the second oxidizer is 2800 ° F.
And the temperature in the second oxidizer is approximately 2800 ° F. Also, since the second oxidizer is arranged to receive a relatively small amount of liquid, it is preferred that any combustible hazardous waste in the liquid be oxidized in the oxidizer means. As embodied herein, it is the second oxidizer that comprises the inlet 60. At the operating temperature of the second oxidizer, the water is evaporated and the solids are directed into a hot gas stream to be combusted, melted or delivered with other non-combustible particulates to the downflow section of the unit. Is.

More preferably, the waste gas from the oxidizing means, the gaseous combustion byproducts and the non-combustible particulates are cooled by the injection of water to form a cooled effluent. Embodied here and first
Dry spray reactor, as schematically depicted in the figure
62 comprises means for injecting water into the dry spray reactor 62. Water is less than about 400 ° F, preferably 350 °
It is preferred to form a cooling effluent having a temperature above F. More preferably, any acid in the cooling effluent is neutralized. As embodied herein and schematically depicted in FIG. 1, the apparatus has means for introducing an alkaline solution to form a neutralized effluent containing non-combustible particulates and waste gas. The waste gas is preferably separated from the incombustible particulates by dry filtration. This step is accomplished by passing the non-combustible particulates and waste gas through a conventional baghouse. The fan connected to the baghouse, in this example the first fan 76, draws suction throughout the system so that the system is operated below atmospheric pressure.

According to the invention, the process comprises the steps of cooling a mixture of molten slag and solid particles to form a harmless aggregate. In the preferred embodiment, the mixture of molten slag and solid particles is directed to a water-filled conveyor. Here, the cooling effect of water cools the mixture, forming a solid, harmless, non-leaching aggregate. The water used to cool the molten material is then redirected for treatment either with the waste water into the second oxidizer or into the cooler 62 as cooling water.

The operation of the device according to the invention results in four emissions: ferrous metal free from harmful substances as it passes through a rotary kiln; if it contains harmful substances it is either bound in the structure of the clinker or of the clinker. A clinker that passes through a rotary kiln, where the composition is redirected to the process until it is harmless. And the third emission is the gaseous emission from the chimney 80, which is mainly carbon dioxide and water. Although the preferred embodiment is not classified as a hazardous waste incinerator and does not require hazardous waste incineration, its air quality certification was applied to Part "B" of a hazardous waste incinerator. Based on the same view.
The present invention meets these criteria without difficulty. In addition to meeting more convincing air quality specifications, aggregates produced from this process, even if they contain heavy metals that would be harmful if separated from the aggregates, are The substance is transformed into a shape constrained in the aggregate.
In particular, the levels of arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver are all well below specified limits. Moreover, the concentrations of insecticide herbicide compounds, acid phenolic compounds, neutral base compounds, and other volatile compounds are well below specified limits. Therefore, even if the input material contains harmful substances, the process produces harmless emissions because the substances are either oxidized by the oxidative treatment or trapped within the structure of the aggregate.

The invention has been described by means of preferred embodiments. However, the present invention is not limited thereto. The scope of the invention is only determined by the appended claims and their equivalents.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F23G 5/16 ZAB B 5/50 ZAB F F23J 1/00 B 15/00

Claims (43)

[Claims] 1. A source (28) for solid waste material comprising (a) a large solid waste and fine particles of waste, and (b) an inlet part (12) and a combustion part for the large solid waste. Guiding to a rotary kiln (10) having (16) and an outlet end (14); (c) separating the large solid waste from the waste particulates; (d) the large solid. Controlling the operating conditions in the kiln so that the waste is combusted to form solid granular primary aggregate, clinker and gaseous combustion byproducts; and (e) volatility in the large solid waste. Volatilizing most of the combustibles at the inlet (12); (f) sucking the gaseous combustion by-products from the kiln (10) and moving them by draft (76); (g) the waste. The first fine particle oxidizer (26) and second fine particles
To the first oxidizer (26), (h) to induce a combustible substance into the first oxidizer (26), and (i) to the first oxidizer (26) and the second oxidizer. Inducing combustion in the vessel (56) to convert the waste fine particles into incombustible fine particles, molten slag, and waste gas, and (j) controlling the temperature in the first oxidizer (26). (K) the non-combustible fine particles and the waste gas are added to the first
Moving from the oxidizer (26) by the suction draft (76), (l) cooling the non-combustible fine particles, the gaseous combustion by-product, and the waste gas, (m) the non-combustible fine particles Is separated from the gaseous combustion by-product and waste gas, and is a method for forming harmless aggregates by utilizing hazardous wastes. (I) The solid granular primary aggregates The first oxidizer (26)
Directing into the second oxidizer (56) and reinducing the non-combustible particulates in individual batches into the second oxidizer (56); and (II) Transferring heat from the first oxidizer (26) to the surface of the deposit of the non-combustible particles and the primary aggregate to form a mixture of molten slag and solid particles, and (III) molten slag Cooling the mixture with solid particles to form a harmless aggregate, the method comprising: 2. The method of claim 1 wherein said deposit has a thermally graded outer surface from said first oxidizer (26) which is conducted onto an outer surface. 3. The beveled outer surface is melted, and molten material on the beveled outer surface flows from the beveled outer surface and is a new surface of unmelted material on the deposit. The method of claim 2, wherein the exposing step. 4. The rotary kiln (10) has a temperature of about 871 ° to 1260 ° C (1
The method of claim 1 operated at an average internal temperature in the range of 600 to 2300 ° F). 5. The method according to claim 1, wherein the operating conditions of the rotary kiln (10) are determined so as to produce the solid product in which a major portion of the solid product is the solid granular primary aggregate. . 6. The first oxidizer (26) receives the waste particulates and an additional combustible material in the form of a liquid fuel, the first oxidizer at about 982 ° to 1649 ° C ( 1800 to 3
The method of claim 1 operating at an average internal temperature in the range up to 000 ° F). 7. The method of claim 6 wherein said liquid fuel comprises combustible liquid waste. 8. The non-combustible fine particles are added to the first oxidizer (2).
The method of claim 1 comprising the step of redirecting back to 6). 9. The second oxidizer (56) receives combustion by-products and non-combustible particulates from the first oxidizer (26), the second oxidizer at about 982 ° to 1538 ° ( 1800 to 2800 °
A method according to claim 1, operating at an average internal temperature in the range up to F). 10. The method of claim 9 including the step of directing said solid particulate primary aggregate to said second oxidizer (56). 11. The method of claim 9 including the steps of mixing the solid granular primary aggregate with the non-combustible particulates and adding the mixture to the second oxidizer (56). . 12. The method of claim 1 including injecting oxygen gas into the first oxidizer (26). 13. The method of claim 1 including the step of injecting oxygen gas into said second oxidizer (56). 14. The method of claim 1 including injecting waste liquid into the second oxidizer (56). 15. The method of claim 1 wherein the waste gas, gaseous by-products of combustion and non-combustible particulates are cooled with water to form a cooled effluent. 16. The cooling effluent is about 177 ° to 204 ° C. (35
16. The method of claim 15, wherein the method is cooled to a temperature in the range of 0 to 400 ° F). 17. The method of claim 15, wherein the acid in the cooled effluent is neutralized. 18. The method of claim 15 wherein the acid is neutralized by the introduction of an alkaline solution to produce a neutralized effluent containing non-combustible particulates and waste gas. 19. The method of claim 18, wherein the neutralized effluent is separated into non-combustible particulates and waste gas by dry filtration. 20. The method of claim 19, wherein the dry filtration step is performed by a baghouse. 21. The kiln (10) and the first oxidizer (26)
The method of claim 1, wherein the second oxidizer and the second oxidizer are operated at a lower pressure than atmospheric pressure. 22. The method of claim 1 including the step of cooling solid material exiting the exit end (14) of the kiln (10). 23. The non-combustible fine particles and the solid granular primary aggregate are accumulated in a container (84) which is in communication with the first oxidizer (26) and the second oxidizer (56). The method according to claim 1, wherein 24. The non-combustible particles and the solid granular primary aggregate are responsive to the non-combustible particles and the solid granular primary aggregate reaching a predetermined level within the container (84). 24. The method of claim 23, wherein the method is contained in the first oxidizer (26) and the second oxidizer (56). 25. A method according to any one of claims 1 to 24, wherein the waste particulates comprise contaminated soil. 26. The method of any one of claims 1-25, wherein the supplemental fuel comprises a flammable liquid waste material. 27. The flammable liquid waste material comprises a liquid selected from the group consisting of organic solvents, waste petroleum products, drilling mud waste liquids and paints. the method of. 28. The method of any one of claims 1-24, including the step of injecting the combustible liquid waste material into the second oxidizer. 29. A rotary kiln (10) having an inlet portion (12) and an outlet end (14) and a first kiln adjacent to the inlet portion of said kiln.
Oxidizer (26) and a second oxidizer (56) in communication with the first oxidizer (26)
A source of solid waste material (28) comprising large solid waste and waste particles, a device (32) for separating said large solid waste from said waste particles, said large solid waste For guiding the waste gas to the inlet portion (12) of the rotary kiln (10), a device for guiding the waste prior to the first oxidizer (26), and inside the kiln. A device (22, 24) for inducing combustion to convert the large solid waste into solid granular primary aggregate, clinker, volatile gas and gaseous combustion by-products; A device for separating from the next aggregate, and inducing combustion in the first oxidizer (26) to melt the waste fine particles, the volatile gas, and the gaseous combustion by-product with non-combustible fine particles. A device for converting slag and waste gas (36,38), said kiln or (76) for moving the gaseous combustion by-product of the above and the waste gas from the first oxidizer (26) and the second oxidizer (56), and the non-combustible particulates and the waste gas. A device (62-66) for cooling the exhaust gas and a device (74,76) for separating the non-combustible particles and the waste gas, and converting harmful waste into harmless and non-leaching aggregate An apparatus (84-102) for inducing the solid granular primary aggregate and reinducing the non-combustible fine particles in the molten slag to form a substantially molten mixture, An apparatus (106) for cooling the substantially molten mixture to form the harmless, non-leaching aggregate. 30. The first and second oxidizer means comprises a plurality of refractory lined vessels (26, 56) in communication with the input portion (12) of the rotary kiln (10). Item 29. The device according to item 29. 31. The method of claim 1 wherein the first oxidizer (26) is arranged to receive the waste particulates, volatile gases from the kiln and gaseous combustion byproducts from the kiln. 30. The device described in item 30. 32. The device comprises a device (36) for injecting auxiliary fuel into the first oxidizer (26).
31. The device according to 31. 33. The device comprises a device (38) for injecting oxygen gas into the first oxidizer (26).
31. The device according to 31. 34. The apparatus of claim 31, wherein the first oxidizer (26) comprises a burner for heating the material therein. 35. The device of claim 29, comprising a device for directing the non-combustible particulates and the primary aggregate to the first oxidizer (26). 36. The apparatus of claim 35, wherein the device for inducing the non-combustible particles and the primary aggregate comprises an accumulator (84) for receiving the non-combustible particles and the primary aggregate. apparatus. 37. The accumulator (84) comprises a device for accumulating the non-combustible particulates and the primary aggregate therein until the level of material in the accumulator reaches a predetermined level. 37. A valve device (98) connected to the accumulator is arranged to enable delivery of integrated non-combustible particulates and primary aggregate to the second oxidizer (56). Equipment. 38. The device of claim 32, comprising a device for directing the non-combustible particulates and the primary aggregate to the first oxidizer (26). 39. The apparatus of claim 31, comprising an apparatus for removing the molten slag from the first oxidizer (26). 40. The device of claim 31, comprising a device (88-102) for directing the non-combustible particulates and the primary aggregate to the second oxidizer. 41. Apparatus according to claim 31, comprising a device (60) for injecting a liquid into the second oxidizer (56). 42. The apparatus comprises a conduit (54) between the first oxidizer (26) and the second oxidizer (56).
31. The device described in 31. 43. The apparatus of claim 42, wherein said conduit (54) comprises a device (42) for removing said molten slag from said first oxidizer (26) and second oxidizer (56). .