WO2016004493A1 - Desulphurising composition and method for producing the same, packaging method and method of use in small pots for the production of iron melts - Google Patents

Abstract

The invention relates to a desulphurising composition, a method for producing the same, a method for packaging and using the same in small pots for producing iron melts, in processes that use refining pots with a capacity of less than two tons of liquid metal, the composition being composed of homogenised calcium oxide (CaO), calcium carbide (CaC₂) and magnesium metal (Mg), aluminium metal (Al) and sodium oxide (Na₂0), preferably of 20-50% CaO, 40-70% CaC₂, 1-20% Mg, 1-10% Al, 1-10% Na₂O, or without the admixture of aluminium metal (Al) and sodium oxide (Na₂O). The production method comprises a preparation route for the mixture of calcium oxide, sodium oxide and aluminium metal, a preparation route for the calcium carbide, a preparation route for the magnesium metal raw material, the homogenisation of the mixture and its transport to the storage silo, where the three routes intersect, the supply of the finished product to the metering silo, where the desulphurising composition is encapsulated into cylindrical tubes by means of a filling device coupled to the bottom of the silo and having an actuation valve. The composition encapsulation tubes (1) can be double tubes (1) or triple tubes (2). The method of use consists in submerging the tube (1 or 2) containing the encapsulated desulphurising composition into the refining pot (6), the tube being gradually lowered to allow the release of thermal energy from the metal bath to disintegrate the tube and release the composition.

Description

 DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, PACKAGING METHOD AND APPLICATION IN SMALL PORTS FOR PRODUCTION OF CAST IRON.

 [01] FIELD OF APPLICATION

 [02] The present invention has its application in the field of metallurgy and relates to a desulphurizing chemical composition, its process of obtaining, whose combination of the formulation and the encapsulated tube packaging method enables its application by immersion during the desulphurization process. of cast irons in small pans.

 [03] Cast iron has particles of different shapes that directly affect its thermomechanical properties. Traditionally, cast irons are classified according to the color of their fracture, and a microstructural analysis shows that grays have graphite (C) in their constitution, whites have carbides (Fe3C, M3C or M7C3) and blends a mixing of the two phases. Graphite can be in compact form, veins or nodules, among others, depending on the presence of small amounts of elements, among which the most important are magnesium and cerium, added in a process known as nodularization.

[04] Hardness and ductility are strongly dependent on the shape of the graphite particle. Nodular shaped particles increase these properties, while longer or irregularly contoured particles are detrimental due to the concentration of stress points. Cast irons can be obtained in various types of reactors, with cubilot, electric arc furnace and induction electric furnace being most commonly used.

[05] Gray cast iron, ternary alloy composed of iron, carbon and silicon as elements of fundamental alloys, presents in its microstructure free carbon in the form of shafts, graphite and may also present carbon combined with iron, iron carbide.

[06] The manufacture of gray cast iron, when performed in a cubilot furnace, uses coke as a heat source for metallurgical fusion and reduction reactions to take place. The amount of sulfur absorbed during these reactions depends on the percentage of this element in scrap and coke. During the solidifying the sulfur present in the scrap and absorbed coke combines with iron as iron sulfide, being located on the boundary of eutectic cells as brittle films with low melting point (1000 ^"C). Thus Combining sulfur with iron is avoided by the addition of manganese in a stoichiometric ratio of 1.7% of the sulfur percentage weight, resulting in more stable sulfides.

 [07] Nodular cast iron, an alloy essentially composed of iron and carbon, with graphite contained in its structure, presented in a spheroidal form. It presents eutectic reaction during its solidification and, as a result, the melting temperatures are much lower than the other ferrous alloys, being used for melting cubilot furnaces or electric arc and induction furnaces. Sequentially, the material is added to a treatment pan for nodularization of the graphite present in the structure in order to leave it in a spheroidal shape. The process of obtaining nodular cast irons in large plants is carried out in three stages: obtaining cast iron (in cubilot furnace, electric induction furnace and / or electric arc furnace), desulphurization and nodularization.

[08] From a chemical point of view, vermicular cast iron does not differ significantly from gray and nodular cast iron. The difference between these alloys is mainly due to the type of morphology of their graphites. The formation of vermicular graphite is due to the action of magnesium, which is a nodularizing element, with an active content between 0.01 and 0.02%. This amount is insufficient to generate nodular cast iron, but sufficient to ensure a stable range of vermicular cast iron without the formation of lamellar graphite. The graphite phase in vermicular cast iron appears as worms or vermicular particles. These particles are elongated and randomly oriented as in gray iron, but are shorter, thicker, and rounder, which gives superior properties such as good mechanical strength, toughness, thermal shock resistance, damping and thermal conductivity. Its microstructure results in stronger adhesion between the graphite and the iron matrix, thereby inhibiting crack initiation and growth and thereby ensuring superior mechanical properties. [09] White cast iron is a Fe-C alloy that solidifies according to the metastable version of the Fe-C diagram, ie carbon manifests itself in the combined form of Fe3C, presenting at room temperature a microstructure consisting of transformed ledeburite ( eutectic mixture of perlite and cementite) and perlite. The most relevant factors favoring metastable reactions are fast cooling laws and low carbon (C) and silicon (Si) contents. This iron is characterized by its white and crystalline color after fracture and is very hard, being the only property responsible for its excellent wear resistance. This last characteristic is mainly due to the massive presence of carbides in the microstructure.

 [010] According to ASTM, all types of cast irons mentioned above have restricted ranges of S specification. Thus, there is a need for desulphurization treatment to achieve the desired ranges. The desulphurization process of cast irons can be performed in intermittent and continuous forms.

 [011] The intermittent desulphurization process is carried out in a "cigar pan" that holds the liquid metal and has a capacity of over two tons, having a porous plug inserted in its bottom and which, disposed in the spout, receives the furnace metal with average temperatures from 1400 ° C to 1500 ° C. At the beginning of the pan filling, the plug is triggered with predetermined flow rates, already stirring the material. After filling about 25% of the pan, a desulfurizing composition is manually added and after the filling is completed, the metal is stirred for a time of approximately 10 to 15 minutes, which may vary according to each process. Once the stirring period is over, desulphurization is completed by manually removing the slag formed by the use of scrapers.

In the continuous desulphurization process the same is achieved by using coincident jets of metal and desulphurizing agent in a "siphon pan" with a capacity of over two tonnes containing nitrogen gas (N2) bubbling plugs. The equipment boils down to a "siphon pan" with pre-calculated nozzle, siphon and slag outlet sizes, equipped with a porous plug system at its bottom, aiming to stir the metal inside and providing a better metal / slag reaction interface. The geometry of this pan allows for desulphurization through the metal and desulphurizing agent interface, promoting the exit of the treated metal on one side and the slag generated on the other, without any intervention by an operator to remove the generated slag. . The system usually has peripheral equipment such as desulphurant composition silo, desulfurant composition dosing belt, conveyor belt and pan chute.

 [013] The main desulphurization reactions occurring in cast iron production processes are:

[014] Mg + [S] → MgS

 [015] CaO + [S] + [Mg] → CaS + [O] + MgO

[016] CaC ₂ + [S] → CaS + 2 [CJ

[017] Na ₂ 0 + [S] + [C] → Na ₂ S + CO _(g)

[018] CaO + [AI] + [S] → CaS + Al ₂ 0 ₃

 [019] The reactor commonly used in small industries is the electric induction furnace due to the short time available for desulphurization treatment and the low volumes of metal used in the process. Due to these factors, in the induction furnace base irons are used, characterized by being metal alloys containing defined ranges of chemical specification of compounds that allow the refining treatment to form any type of cast iron, be they gray, white, nodular. and or vermicular. Because of the need for this strict control of the base iron's chemical specification, its cost is quite high.

 [020] TECHNICAL PROBLEM

[021] For the desulphurization of cast irons there is a need for a kinetic environment where the desulphurant material may interact with the metal bath. In order to provide this contact, porous plugs are used at the base of the metal bath treatment pan in order to inject an inert gas not to react with the metal bath. Subsequently desulphurizing compositions are used in continuous desulphurization processes and using treatment pans with capacities exceeding two tonnes of liquid metal.

 [022] There are no technically feasible processes for performing desulphurization of cast irons in treatment pans of less than two tonnes, as desulphurization time is not sufficient, either intermittently or continuously, due to the low volume of metal to be treated. leading to high temperature drops of the metal. The efficiency of the desulphurization process is dependent on the availability of treatment time and the volumes of metal to be treated. Thus, desulphurizations in pans less than two tons have low efficiency.

 In the prior art, it is known to use the source materials of the compounds used in the formulation described in the present invention only in co-injection processes for pig iron desulphurization. However, for desulphurization of cast irons the use of the desulphurizing composition is not cited in the prior art.

 [024] STATE OF THE TECHNIQUE

 [025] In the state of the art no patents have been found for the control or reduction of sulfur with the same composition described here, as well as the manner in which the desulphurization process is carried out, besides the possibility of application in pans with capacity less than two tons as claimed in the present patent.

 US 47055961 describes a method of a composition used for desulphurisation of nodular cast irons, composed of magnesium and calcium oxide, where magnesium is heated to a certain temperature until

 I

 molten, then calcium oxide is added. After the mixture is cooled and fully solidified, it is ground and used for desulphurization. It is

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 The patent differs from the present one in that it has a distinct composition as well as the method of obtaining and applying it.

[027] Patent BR 8901759 describes a method of desulphurization of cast iron produced by a blast furnace prior to conversion to steel. In this process there is use of a large length composite tubular shell where inside there is an axial zone, where locates magnesium in a powdery way or granular, and an annular zone, separated from the axial zone by an intermediate wall, where a puivorent or granular raw material is located. Consequently, a neutral gas is blown into the process and the slag generated is removed. The disclosed patent differs from the present patent in that it is used in desulphurization of cast iron from a blast furnace. It also differs in the way the raw material is packaged in the metal composite as well as the characteristics of the composite.

 [028] PI 95101306 B1 describes an apparatus which enables refining treatments of cast irons as well as inoculation for formation of nodular cast irons, either in continuous or batch processes. Although it is a similar alternative, it differs from the present patent in that it only contemplates the possibility of carrying out the desulphurization treatment. On the other hand, the patent described herein presents a desulphurizing composition, a device for its storage and application and, mainly, enables the process of desulphurization of cast irons in pans with a capacity of less than two tons.

 [029] To solve this problem, a desulphurizing composition, a new form of storage and a differentiated form of addition have been developed, which make it possible to desulphurize cast irons in treatment pans with a capacity of less than two tonnes.

 [030] PROCESS FOR OBTAINING CHEMICAL COMPOSITION OF DISULFURANT

[031] In order to obtain the desulphurising chemical composition, raw materials are used as sources of the compounds calcium oxide (CaO), calcium carbide (CaC ₂ ) and metallic magnesium (Mg), aluminum aluminum (Al) and sodium oxide (Na ₂ THE). Raw materials are selected and chemically analyzed for quality control. Calcium carbide and calcium oxide are milled in known milling processes, the source materials of sodium oxide and metallic aluminum are added to the calcium oxide milling circuit to be mixed with the calcium carbide and then homogenized. Subsequently, metallic magnesium is added to the formed mixture. After mixing all the raw materials to form the desulphurizing composition, their encapsulation in cylindrical tubes that allow their application efficiently for the proposed purposes.

 [032] The process for obtaining the desulphurizing chemical composition may be understood through the attached flow chart below:

 Flowchart 1 represents the preparation of the raw materials to the encapsulation phase of the resulting desulphurizing chemical composition.

 According to Flow Chart 1, the desulfurizing chemical composition is obtained by the following steps:

 [035] 1 - Preparation of the mixture of calcium oxide, sodium oxide and metallic aluminum:

 [036] 1.1 - supply of calcium oxide, sodium oxide and metallic aluminum in stock bays;

 [037] 1.2 - transport by hopper equipped with guillotine dosing system, where the flow of material is regulated, to the pendulum mill;

 [038] 1.3 - belt provided with system for metering the amount of fluidizing additive conveys the material for additive addition and supply to the roller mill;

 [039] 1.4 - grinding of calcium oxide, sodium oxide and metallic aluminum;

[040] 1.5 - Particle size classification of the mixture in aeroclassifier suspension process and cyclone pass and bag filter dedusting system;

 [041] 1.6 - Mixing is routed through a set of mug lifts to the passing silo;

 [042] 1.7 - from the silo will be sent to the mixer which is the intersection point of the first two raw material preparation routes.

[043] 2 - Preparation of calcium carbide:

[044] 2.1 - supply of calcium carbide in the bay;

[045] 2.2 - passage through the underground silo;

 [046] 2.3 - by means of tank lifts and conveyor threads is sent for grinding in the ball mill;

[047] 2.4 - routing of ground calcium carbide by conveyor screw system to the through silo; [048] 2.5 - From the silo will be sent to the mixer, which is the intersection point of the routes of the first two preparation routes.

[049] 3 - Homogenization of the new mixture:

 [050] 3.1 - a prepared mixture of calcium oxide, sodium oxide and metallic aluminum and the ground calcium carbide is homogenised in the mixer;

 [051] 3.2 - Mixing is routed through tank lifts and conveyor threads to the storage silo.

[052] 4 - Preparation of the magnesium metal raw material:

[053] 4.1 - Supply of raw material on the hoist;

[054] 4.2 - obtaining the weight of the stipulated metal magnesium by batch;

[055] 4.3 - referral to magnesium silo;

 [056] 4.4 - the silo will be sent to the storage silo, which is the intersection point between the three preparation routes 1, 2 and 4.

[057] 5 - Obtaining the desulphurizing chemical composition:

[058] 5.1 - Supplying the storage silo with the raw materials prepared by the three preparation and routing routes to the mixer;

[059] 5.2 - homogenization of the mixture, the mixer being closed and inerted to be added to the mixture of calcium carbide, calcium oxide, sodium oxide, metallic aluminum and metallic magnesium;

 [060] 5.3 - Desulfurizing composition is routed to the storage silo;

[061] 5.4 - Desulfurizing composition is encapsulated in tubes by a potting device coupled to its lower base.

[062] FORMULATION OF DESULFURANT CHEMICAL COMPOSITION

[063] As a result of the desulphurising chemical composition in which the source materials of the compounds calcium oxide (CaO), calcium carbide (CaC ₂ ), magnesium, sodium oxide and metallic aluminum are comminuted, formulation:

[064] 20 to 50% CaO + 40 to 70% CaC ₂ + 1 to 20% Mg + 1 to 10% AI + to 10% Na ₂ O

[065] The desulphurizing chemical composition may also have the following formulation: [066] 20 to 50% CaO + 40 to 70% CaC ₂ + 1 to 20% Mg

[067] The combination of the compounds in the present formulation, as well as the ratio described above, affords high desulphurization efficiency due to the participation of calcium carbide, calcium oxide, metallic magnesium, sodium oxide and metallic aluminum. Magnesium metal and aluminum react with oxygen dissolved in the metal bath, providing a chemical imbalance, making Ca and Na present in the composition materials available to perform the desulphurization action. Magnesium also has the function of promoting agitation, due to its low boiling point (approximately 1,090 ° C), and when present in the metallic bath vaporizes, since the typical medium temperature is above the mentioned boiling point, forming magnesium in gaseous state (Mg _g ), thus promoting agitation in the liquid metal. The incorporation of sodium oxide and metallic aluminum in the mixture is an alternative, as they potentiate desulphurization, but increase the cost of chemical composition.

 [068] Following the process of obtaining the desulphurizing chemical composition, the product will be sent to a dosing silo to be filled into cylindrical tubes, which may have different constructive arrangements as described below.

 [069] METHOD OF ENCLOSURING CHEMICAL COMPOSITION METHOD

 [070] The desulphurizing composition is encapsulated in tubes through a filling device coupled to the bottom base of the storage silo via a drive valve. After filling, the cylindrical tubes are sealed and labeled and then sent for storage.

 Encapsulation tubes of the desulphurizing chemical composition may be understood from the accompanying attached figures below and from the following description:

 [072] Figure 1 is a view of the male socket cylindrical tube of the double encapsulated cylinder.

[073] Figure 2 is a view of the sealing ring. [074] Figure 3 is a view of the female socket cylindrical tube of the double encapsulated cylinder.

 [075] Figure 4 is a view of the assembly of the double encapsulated cylinder.

[076] Figure 5 represents view of the double encapsulated cylinder.

[677] Figure 6 represents view of double encapsulated cylinder and sealing ring positioning.

 Figure 7 represents a view of the components of the triple encapsulated cylinder.

[079] Figure 8 is a view of the assembled triple encapsulated cylinder and sealing ring positioning; Detail A illustrates the sealing ring.

[080] Figure 9 represents view of the triple encapsulated cylinder.

[081] Figure 10 depicts details of triple encapsulated cylinder assembly and sealing ring positioning.

 According to Figures 1 to 6, the double encapsulated cylinder (1) has the following constructive characteristics:

 [083] - Cylindrical tube (1a), preferably of cardboard, having at one end a male socket (1w) and the other end plugged with a stamped tin material (1x), in a compatible size to seal the tube (1b) containing the female socket (1 y);

 [084] - cylindrical tube (1b), preferably of cardboard, having at one end a female socket (1y) and the other end plugged with a stamped tin material (1z).

 [085] O-ring (5) of compatible thickness to be inserted into the fitting between the tubes (1a and 1b), separating the desulphurizing composition into the tube (1).

 According to Figures 7 to 10, the triple encapsulated cylinder (2) has the following constructive characteristics:

[087] - central cylindrical tube (2a) and cylindrical end tubes (2b and 2c), preferably made of steel, with external threads (2x) at the ends, and at the ends of tubes (2a to 2c) and (2a to 2b) ) are threaded plugs (3) of PVC material; [088] - between the tubes (2a and 2b) and (2a and 2c) are threaded gloves (4) galvanized for light conduit, with internal threads at both ends;

 [089] - nylon plug (5) of compatible thickness to be inserted into sleeves (4), separating the desulphurizing composition into the tube (2).

 [090] METHOD OF APPLICATION OF ENCAPSULATED DESULFURANT COMPOSITION IN PILLS IN PANS WITH UP TO TWO TONS CAPACITY

 [091] The method of applying the composition to pans of up to two tonnes capacity may be either by hand or mechanically, as set out in the accompanying figures below and in the following description:

 [092] Figure 11 represents a view of the beginning of the application manually.

 [093] Figure 12 represents a sequence view of the manual application with the tube already immersed in the metal bath, the deterioration of the tube and release of the desulfurizing composition encapsulated therein.

 [094] Figure 13 represents the completion of manual application with tube deterioration and release of the desulfurizing composition encapsulated therein.

According to Figures 11 to 13 illustrating the manual form, the method of applying the desulfurizing composition of cast irons is by dipping encapsulated cylindrical tube (1 or 2) into the treatment pan (6) by coupling one end of the tube to a rod (7). The rod (7) is suspended and immersed in the metal bath in a treatment pan (8) with a capacity of less than two tons of metal, and the encapsulated tube (1 or 2) is consumed due to the thermal energy released by the metal bath. During this process, due to the kinetics caused by the desulphurizing reactions of calcium oxide (CaO), calcium carbide (CaC2), sodium oxide (Na ₂ O), as well as deoxidation and stirring by metallic magnesium (Mg), and Finally the deoxidation by the action of aluminum, desulfurization of the metallic bath occurs.

[096] The process of obtaining the composition ensures a sulfur partition ratio sufficient to prevent reversal of the removed sulfur under operating conditions for cast iron treatment. The addition of said composition effectively provides increased efficiency, reduced treatment time and reduced thermal loss of molten material in treatment pans with capacities of less than two tons.

 [097] Desulphurization occurs with the encapsulated tube exhibiting stable behavior, ie uniform burning throughout the process and in parallel acceptable desulphurization results are obtained compared to those commonly obtained in intermittent and continuous desulphurization of cast irons where results below 0.020%. In addition, the results obtained occur at shorter treatment times.

 [098] In one embodiment of the present invention, foundries having cubilot furnaces, induction furnaces with production capacities of one hundred kilograms, three hundred kilograms, five hundred kilograms and two tons and their respective treatment pans were used.

Claims

[01] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTS FOR PRODUCTION OF CAST IRONS, in processes using treatment pans with capacities of less than two tonnes of liquid metal, characterized by the desulphurizing composition be formed by homogenized calcium oxide (CaO), calcium carbide (CaC ₂ ) and magnesium metal (Mg), aluminum metallic (Al) and sodium oxide (Na20), preferably with contents of 20 to 50% CaO, 40 70% CaC ₂ , 1 to 20% Mg, 1 to 10% Al, 1 to 10% Na ₂ O. [02] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTS FOR PRODUCTION OF CAST IRON, in processes using treatment pans with capacities of less than two tonnes of liquid metal, characterized by the desulphurizing composition be formed by homogenized calcium oxide (CaO), calcium carbide (CaC2) and metallic magnesium (Mg), preferably with contents of 20 to 50% CaO, 40 to 70% CaC ₂ , 1 to 20% Mg .  [03] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTION PANS FOR PRODUCTION OF CAST IRONS according to claims 1 and 2, wherein the process for obtaining the desulphurant chemical composition is characterized by: present the following stages: - preparation of the mixture of calcium oxide, sodium oxide and metallic aluminum in stock bays; transport by hopper equipped with guillotine dosing system, where the flow of material is regulated, to the pendulum mill; belt provided with system for metering the amount of fluidizing additive conveys the material for additive addition and supply to the roller mill; grinding of calcium oxide, sodium oxide and metallic aluminum; particle size classification of the mixture in the aeroclassifier suspension process and cyclone pass and bag filter dedusting system; routing of the mixture through a set of lifts from mugs to the silo of passage; from the silo will be sent to the mixer which is the intersection point between the first two preparation routes;  - preparation of calcium carbide by supply in the stall; passage through the underground silo; by means of tank lifts and conveyor threads it is sent for grinding in the ball mill; routing ground calcium carbide by conveyor screw system to the silo; from the silo will be sent to the mixer which is the intersection point between the first two preparation routes;  - homogenization of the prepared mixture of calcium oxide, sodium oxide and metallic aluminum and the calcium carbide already ground, and then conveyed from their respective silos through tank lifts and conveyor threads to the storage silo;  - preparation of the magnesium metal raw material by supplying the raw material to the hoist; obtaining the weight of the stipulated metal magnesium by batch; routing to the magnesium silo, from where it will be sent to the storage silo, which is the intersection point between the three preparation routes;  - obtaining the desulphurising chemical composition by supplying the storage silo with the raw materials prepared by the three routes; homogenization of the mixture, the mixer being closed and inerted to be added to the mixture of calcium carbide and calcium oxide, whether or not accompanied by sodium oxide and metallic aluminum, to metallic magnesium; supply of the finished product to the storage dosing silo. [04] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTION PANS FOR PRODUCTION OF CAST IRONS according to claims 1 to 3, wherein the method of encapsulating the desulfurizing chemical composition is characterized by: being the desulfurizing composition encapsulated in cylindrical tubes through a filling device coupled to the lower base of the metered dose storage silo through a drive valve; After filling, the cylindrical tubes are sealed, labeled and sent for storage. [05] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTION POWDER PRODUCTS according to claim 4, wherein the double encapsulation tube of the desulfurizing chemical composition is characterized by having cylindrical tube (1), preferably of cardboard, subdivided into tube (1a) with male end (1w) and the other end plugged with a stamped tin material (1x), in a compatible size to seal the tube (1b) containing the female socket (1y); and another cylindrical tube (1b) of the same material, having at one end a female socket (1y) and the other end plugged with a stamped tin material (1z); seal ring (5) of compatible thickness to be inserted into the fitting between the tubes (1a and 1b) by dividing the desulfurizing composition within the tube (1).  [06] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTION POWDER PRODUCTS according to claim 4, wherein the triple encapsulation tube of the desulfurizing chemical composition is characterized by having cylindrical tube (2) subdivided into central section (2a) and ends (2b and 2c), preferably made of steel, with external threads (2z) at the ends, and at the ends of the tubes (2b and 2c) are threaded plugs (3) PVC material; between the tubes (2a to 2c) and (2a to 2b) are threaded gloves (4) galvanized for light conduit, joining the tubes (2a, 2b, 2c); nylon plug (5) of compatible thickness to be inserted into sleeves (4) by dividing the desulphurizing composition into the tube (2). [07] DESULFURANT COMPOSITION AND ITS PRODUCTION PROCESS, METHOD OF PACKAGING AND APPLICATION IN SMALL PORTS FOR PRODUCTION OF CAST IRONS according to claims 1 to 6, in which method of applying the encapsulated desulphurant composition in pans capable of up to two tonnes by hand or mechanically, characterized in that they consist of the immersion of the double (1) or triple (2) cylindrical tube containing the encapsulated desulphurizing composition in the treatment pan (6), manually, by coupling one of its ends to a suspended rod (7), which should be gradually lowered, so that the release of thermal energy from the metallic bath causes its deterioration and release of the desulfurizing composition encapsulated therein, and as a result of the kinetics caused by calcium oxide (CaO), calcium carbide (CaC2), sodium oxide (Na ₂ O) Mg), and finally the deoxidation by the action of aluminum, occurs the desulfurization of the metallic bath.