The present invention disclosed herein is an improvement of Applicant's patent entitled “Apparatus for Carbonizing Material,” bearing U.S. Pat. No. 5,639,353, issued on Jun. 17, 1997, hereinafter referred to as the “referenced patent.”
Referring to the drawings, the specification, and the claims disclosed in the referenced patent, certain major and critical defects were identified when the reference patent was attempted to be put into practice. These defects were in the following areas:
As shown in Supplement Figures A and B, heating tiles 40, which form walls 38 and 39, possess a great number of wall joints that must be sealed, especially in view of the operation being conducted at a positive pressure and at high temperature. Since both walls provide a taper that grows in diameter towards the discharging end of chamber 10, the number of tiles increases, which means more joints are created. Further, since each row of tiles is of different dimensions by virtue of the taper, separate patterns, molds, and cores have to be made for each row of outer wall 38 and for each row of inner wall 39.
Also, there is the issue of supporting inner wall 39 within chamber 10; it is conceivable that inner wall 39 can be supported at the charging end, which is at room temperature; however, it is inconceivable that inner wall 39 can be supported at the hot discharge end, as it will interfere with the discharging of the coke at the hot end. To accomplish a productive capacity of several tons of coke per hour from chamber 10, it is estimated that coking chamber 10 would measure some 40 feet in length; supporting, in a cantilevered fashion, the massive weight of the inner wall 39 from the cold end only, will cause the hot end of inner wall 39 to deflect downward at the hot discharge end, thus destroying the concentric configuration of annulus 37 and affecting its uniform heating.
Referring in particular to
It is to be noted in Supplemental Figures A and B, which are attached herein to facilitate description, two full-size commercial courses of tiles of silicon-carbide (nitride bonded) were specially manufactured as a test to determine whether or not it would be practical to put into commercial use an inner wall to simulate inner wall 39, represented in
Since the tiles that makeup outer wall 38 and inner wall 39 of coking chamber 10 interlock with one another, it is not possible to replace damaged tiles as the inner wall must be removed from chamber 10, which is a major undertaking because of the massive weight and accessibility. This means that the entire chamber would have to be disengaged from the steel tower building in which would be housed, brought down to ground level, placed on a flat car, and transported to the maintenance shop, while a spare chamber is mounted in place of the one that requires maintenance; in the meantime, serious losses in productivity would occur.
Because of the special tiles, number of molds and cores, and the structure to support the massive weight of coking chamber 10, the project became so costly that it was decided to find technical and economic alternatives. Further, since the maintenance was expected to be severe, operating costs would also be excessive.
The main object of the instant invention is overcoming the disadvantages stated above with respect to the referenced patent.
Another object of the present invention is the incorporation of the new improvements that are mentioned hereinafter to insure that the invention becomes technically practical.
Still another object of the present invention is to lower capital and operating costs in order to make the invention both technically as well as economically viable.
Further still, another object of the instant invention is to minimize the use of special, expensive metallurgical coal(s) to make specification coke by substituting some low-cost, abundant, non-metallurgical coal but still succeed in producing specification coke.
Therefore another object of the instant invention is to improve the quality of the coke produced.
These and other objects of the instant invention will become more apparent to those skilled in the art to which this invention pertains and particularly from the following description and appended claims.
Reference is now made to the accompanying drawings to enable the detailed description of the instant invention with the aid of numerals. These drawings form a part of the specification wherein like reference characters designate corresponding parts in the various views. By way of example, the material to be carbonized in this description will be directed towards the use of coal and its conversion into coke, which is mainly used in the making of blast-furnace iron, and also it is to be noted that the embodiments shown herein are for the purpose of description and not limitation.
Referring to
Referring to
In addition to ram 39, a mandrel marked by numeral 41, which is adapted to advance and retract independently from ram 39, with the push and pull action being effected by hydraulic actuators 46 that connect to mandrel 41 by means of yoke 47, which takes the form of a massive weldment marked by numeral 38. It is to be noted that ram 39 provides a bore through its center to accommodate mandrel 41 to pass through ram 39 in such a way that mandrel 41 is surrounded by ram 39. It is further to be noted that mandrel 41 takes the shape of a pipe with a bore of such a dimension as to accommodate lance 25 to directly pass through mandrel 41, and in essence pass indirectly through ram 39 by virtue of mandrel 41 passing through ram 39. Lance 25 serves as an injector of a gas containing oxygen in order to combust a small portion of coal plug 36 under suppressed condition (deficiency of oxygen), to generate the thermal energy required to devolatilize the coal and convert it into coke. The injection of the coal at a cold start is assisted by start-up burner 24,
Referring now to
It is to be noted that in providing lance 25 wherein some of the coal charged is combusted under suppressed conditions (in a pressurized, controlled reducing atmosphere), heat transfer within chamber 12 is markedly improved, thus enhancing the rate at which coal is converted to coke by heating the coal directly within chamber 12, resulting in increased productivity. Further, the coal/coke is heated peripherally by means of injection nozzles disposed through shell 40 and refractory 41, one of which being marked by numeral 80, with such nozzles being supplied with a gas containing oxygen furnished by manifold 79, thus providing direct, bi-directional, efficient heating.
In the making of coke for blast furnace use to convert iron ore into iron, a special coke is used; it is derived from special coal known in the ironmaking industry as “metallurgical coal.” Because of its scarcity, it is an expensive coal, especially when compared to other coals such as steam coal used in raising steam in boilers for thermal heating and/or the generation of power.
In the instant application wherein some coal is combusted in chamber 12, the objective is to minimize the combustion of metallurgical coal. To achieve this objective, numeral 12 is the coking chamber, numeral 26 is the charger, numeral 35 is the feed hopper, numeral 39 is the ram, numeral 41 is the mandrel, numeral 25 is the injection lance, numeral 43 is the nozzle at the tip of lance 25, and numeral 48 is one of the several nozzles disposed at the side of lance 25, numeral 49 is the non-metallurgical coal, numeral 50 is the metallurgical coal, numeral 51 is the refractory/insulation which is configured as a monolithic structure that is reinforced with metallic needles such as stainless steel needles, marked by numeral 81, somewhat similar to imbedding steel wire for reinforcing concrete; this structure is cast in place against shell 40.
In the case of heating the material peripherally directly by combusting material to be carbonized, the air or oxygen per se is introduced through shell 40 by means of injectors, one such injector being marked by numeral 80 supplied by manifold 79. In this case, where combustion takes place peripherally and the material is metallurgical coal, it is possible to also charge low-cost, non-metallurgical coal around the perimeter of the metallurgical coal to essentially minimize the combustion of expensive metallurgical coal by providing an additional mandrel that circumscribes ram 39 to form a ring of non-metallurgical coal around the peripheral of the metallurgical coal. In so doing, the combustion effected by injectors, such as injector 80, consumes the ring of non-metallurgical coal, instead of combusting peripherally expensive metallurgical coal. In the case of heating the material peripherally indirectly, numeral 52 is the manifold for distributing hot heating gas into a plurality of small-diameter flues installed in refractory/insulation 51, one such flue being marked by numeral 53 carrying hot gases that heat refractory 51, which in turn heats the material indirectly.
Referring now to
Referring to
Reference is now made to all Figures to explain the operation of the instant invention, with the explanation being initiated by making use of
The conversion of the metallurgical coal into metallurgical coke, as illustrated in
Downcomer 13 is made up of a plurality of pipes grouped together to form a manifold that enables the newly formed coke to be directed to coke quenching chamber 14, when the upper valves (such as valve 28) are individually opened in a predetermined sequence, thus guiding the hot coke from any of the five coking chambers into quenching chamber 14.
Quenching chamber 14, which is equipped with discharge valve 29, possesses several injection points at different elevations, marked by numeral 30 for injecting a coolant to drop the temperature of the coke to such a degree as to be discharged into the atmosphere without causing emissions. The coolant generally is water, but it can be steam or a gas, as for example flue gas containing CO2+N2, which the hot coke in quenching chamber 14 can convert to 2CO+N2, or a feedstock gas that can, in turn, be converted to a by-product such as fertilizer; it is to be noted that the injection of such gas is shown by dotted conduit 55 at the bottom of quenching chamber 14 and exiting at the top of chamber 14 marked by numeral 56. In the event that steam is injected by means of line 55, water gas (CO+H2) can be formed; such gas may be directed to separator 33 for removal of excess moisture in the water gas. Periodically, valve 28 is closed while valve 29 is opened to discharge the quenched coke into chute 15, thence onto vibrating screen 16 wherein the undersized coke (known as “breeze”) is separated from the specification coke, which is transported by conveyor 31 to stacker 17 for storage.
It is to be noted that when injecting a gas containing CO2 into the hot coke in quencher 14, the coke tends to cool; therefore, in using this injection practice, two coke-quenching chambers (“a” and “b”) are provided, with “a” being injected with gas containing CO2, while the other is blown with air or oxygen in order to make up for the heat loss, and when “b” is being injected with gas containing CO2, air or oxygen is blown through chamber “a” to raise its temperature. Instead of providing two quenching chambers, another approach is to use only one, but used when the hot coke is above the temperature at which the CO2 is reduced to 2CO by making use of a by-pass valve to interrupt the flow of the gas when the coke stops reducing the CO2 into 2CO.
By continuing to refer to
Once the sorbent in cracker/desulfurizer 19 is spent, the sorbent is transported from the bottom of cracker/desulfurizer 19 to the top of regenerator 20 by means of conveyor 34. During the regeneration of the sorbent, the sulfidated gas leaving the top of regenerator 20, by means of stream 62, is passed through sulfur condenser 18 to recover the sulfur in liquid form and stored in tank 63. In cases where the clean gas from the top of cracker/desulfurizer 19 needs to be treated for the removal of mercury, clean gas cooler 64 is provided, which cools the clean gas prior to being passed through an activated-carbon bed system marked by numeral 21, shown in
The clean desulfurized gas devoid of mercury is then passed as stream 65 through bag-house 66 to remove any particulate matter, producing ultra-clean stream 67, which, destined to be used as fuel or chemical feedstock, is fed to gas main 68; it is to be noted that the joining of stream 67 to stream 68 is to be assumed that it is obstructed in
In cases where it is required that gases containing carbon dioxide (CO2) need to be controlled because of climate change, by way of example, system 69 is provided (shown in
Referring now to
The details of construction mentioned above are for the purpose of description and not limitation, since other configurations are possible without departing from the spirit of the invention. Further, other materials besides coal can be carbonized in the apparatus herein described.