Description:TECHNICAL FIELD

The present disclosure relates to the field of coke manufacturing. Particularly, but not exclusively, the present disclosure relates to an apparatus for producing coke from coal tar pitch. Further embodiments of the present disclosure disclose apparatus and a method of producing needle coke or pitch coke from the coal tar pitch.

BACKGROUND

Needle coke is usually required in manufacturing of graphite electrodes, which are used in submerged electric arc furnaces of high capacities. Electric arc furnaces use high power electric arcs for steel production. Needle coke is the primary raw material used for the manufacturing of graphite electrodes from arc furnace in the steel and aluminum industries. It is a special type of coke that exhibits superior properties such as structural characteristics, high-temperature resistance, high electrical resistance, oxidizability, and Coefficient of Thermal Expansion (CTE). Electric arc furnaces are pollution-free and have efficient metallurgical control due to which the steel production through the electric arc furnace method has significantly increased. Consequently, the consumption of needle coke to manufacture the graphite electrodes used in the electric arc furnaces has also significantly increased.

Needle coke is usually produced by a coker unit along with a furnace housing the coker unit. The coker unit includes a liner into which the feedstock is fed. Feedstocks utilized for needle coke production include coal tar pitch, fluidized catalytic cracker decant oil (also known as slurry oil), petroleum vacuum residues, ethylene tar pitches and solvent-refined coals. The coal tar pitch enters the liner and is subsequently heated by the furnace. The desired temperature is maintained in the coker unit to convert the coal tar pitch into solid mass of coke. Further, the liner is maintained at suitable pressure while the coal tar pitch is heated by the furnace. Once, the coal tar pitch is converted to coke, the liner is removed from the coker unit and the coke is further removed from the liner.

Conventional coker units include inlet pipe that are often configured at the bottom of coker unit. The feed enters the liner of the coker unit through the inlet pipe configured at the bottom of the coker unit. Once the liner is filled with the feed to required levels, the feed is subjected to suitable temperature and pressure for producing coke. As the coke solidifies, the inlet pipe inside the liner sticks to the coke when coke is cooled. Consequently, removal of inlet pipe from the solidified coke becomes extremely difficult. Further, once the feed begins to flow through the inlet pipe into the liner, the inlet pipe may be jammed due to the high viscosity of the feed and the orientation of the inlet pipe at the bottom of the liner. Consequently, the time taken for the liner to be filled with the feed also increases drastically. Further, the liners housed inside the coker unit are cylindrical in shape and the diameter remains the same through-out the length of the liner. As the coke solidifies in the liner, the coke may get stuck between the liner and the coker unit. Consequently, the removal of the liner from the coker unit becomes difficult as the liner may be jammed due to the solidified coke between the liner and the coker unit. Removal of liners from the conventional coker unit is often difficult and tedious due to the configuration of the liner.

Further, hydrocarbon vapors are generated as the feed is processed to coke in the liner by subjecting the feed to high temperature and pressure. The hydrocarbon vapors rise up and reaches to a top cover of the coker unit. The hydrocarbon vapors may escape out of the coker unit through an aperture defined in the top cover of the coker unit. The vapors which do not escape through the aperture may condense to a liquid state and the liquid hydrocarbons may trickle down in the coker unit. The liquid hydrocarbons may trickle down from the top cover through coker wall. The condensed liquid accumulates in an annular gap between the coker and liner. As the coke inside the liner solidifies when cooled down, the liquid hydrocarbon accumulated in the annular gap also solidifies. Consequently, the solidified hydrocarbons in the annular gap between the coker unit and the liner cause the coker unit and the liner to stick together. Consequently, removal of the liner from the coker unit for the extraction of coke becomes difficult.

Coker units are closed and pressurized systems due to which the measurement of the temperature inside the liner is often difficult. During the processing of feedstock to coke, it becomes critical to measure and monitor the temperature that the feedstock is subjected. The ability to measure the temperature of the feedstock while being processed to coke and thereby monitor the temperature that the feedstock is subjected to inside the liner, often dictates the quality of the coke that is formed inside the liner. Conventional coker units do not comprise of any means for measuring the temperature of the feedstock or the coke inside the liner. The temperature around the circumference of the liner may be suitably measured but the measurement of the temperature along the central region inside the liner of conventional coker units is not possible. Consequently, the quality of coke produced in conventional coker units may often not be of the desired levels.

Ayyappan et al (US patent No. 9375656) describes a method for producing a needle coke precursor from slurry oil having low levels of nitrogen and sulphur. Oyama et al. (US patent no. 7964173) describes the process in which feedstock composition is provided to produce needle coke from the heavy oil. Ward et al. (US patent no. 3617515) describes a process of producing needle coke from the coal tar pitch. Migitaka et al. (US patent No. 4127472) talks about the process for preparing a raw material for the manufacture of needle coke by removing insoluble substances containing quinoline insoluble from coal tar or coal tar pitch. Murakami et al. (US Patent No. 4210517) describes the invention relates to the preparation of carbonaceous products from coal.

The above applications or patents describe the details of converting coal, coal tar, coal tar pitch, and petroleum products into needle coke by different means and taking quinoline insoluble (QI) free fraction or removing Sulphur and nitrogen from the feed. The coker unit is the main processing unit in which coal tar pitch is converted into needle coke. However, these prior arts do not describe any constructional modifications or improvements to the coker unit. The prior art only talks about the processes through which the impurities are removed or the conversion of raw materials into needle coke.

The present disclosure is directed to overcome one or more limitations stated above or other such limitations associated with the conventional methods or apparatus.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional system and method are overcome by the system and method as claimed and additional advantages are provided through the provision of the system as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the disclosure, an apparatus for producing coke from coal tar pitch is disclosed. The apparatus includes a coker unit defining a chamber, where the coker unit is configured to receive heat energy from a furnace. A liner is removably housed in the coker unit and the liner is defined with a tapered profile from a top end to a bottom end. An inlet pipe extending along a vertical axis of the coker unit into an internal volume of the liner from the top end of the of the liner is provided. The inlet pipe is configured to feed the coal tar pitch to the internal volume of the liner where, the coal tar pitch inside the liner is subjected for heating to a pre-determined temperature under a predetermined pressure for producing the coke.

In an embodiment of the disclosure, the apparatus includes a closure member enclosing an upper portion of the coker unit and the closure member is defined with an enclosure to accommodate the inlet pipe.

In an embodiment of the disclosure, the taper angle of the tapered profile of the liner ranges from 0.9 degrees to 1.3 degrees from the top end of the liner to the bottom end of the liner.

In an embodiment of the disclosure, the apparatus includes an exhaust hood extending from closure member and into the coker unit.

In an embodiment of the disclosure, the exhaust hood is disposed above the liner and a bottom end of the exhaust hood is defined with an inwardly bent profile.

In an embodiment of the disclosure, the apparatus includes an internal pipe positioned inside the liner, where the internal pipe extends from the closure member, substantially along the length of the liner.

In an embodiment of the disclosure, the internal pipe is configured to house a plurality of thermocouples for measuring temperature of the coke formed inside the liner.

In an embodiment of the disclosure, a base plate is provided at the bottom end of the liner, where the base plate is defined with a plurality of hooks to facilitate the removal of the liner from the coker unit and to subsequently remove the coke from the liner.

In an embodiment of the disclosure, the pre-determined temperature for heating the coal tar pitch inside the liner ranges from 420 0C to 550 0C and the pre-determined pressure inside the liner ranges from 1.013 bars to 10 bars.

In another non-limiting embodiment of the disclosure, a method of assembling an apparatus for producing coke from coal tar pitch is disclosed. The method includes removably accommodating the liner inside the coker unit, where the liner is defined with tapered profile from the top end to the bottom end and the coker unit. The coker unit is housed in the furnace and the furnace heats the coker unit. The next step involves positioning the inlet pipe such that the inlet pipe extends along a vertical axis of the coker unit into the internal volume of the liner from the top end of the liner, where the inlet pipe is configured to feed the coal tar pitch into the internal volume of the liner. The coal tar pitch inside the liner is subjected for heating to the pre-determined temperature under the predetermined pressure for producing the coke.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristics of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Fig. 1 illustrates a schematic view of an apparatus for producing coke, in accordance with an embodiment of the present disclosure.

Fig. 2 illustrates a process flow diagram of the apparatus of Fig. 1, in accordance with an embodiment of the present disclosure.

Fig. 3 illustrates a process flow diagram for manufacturing needle coke, in accordance with an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the apparatus for producing coke from coal tar pitch illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other devices for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure. The novel features which are believed to be characteristic of the disclosure, as to its organization, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such mechanism. In other words, one or more elements in the device or mechanism proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the mechanism.

Embodiments of the present disclosure discloses an apparatus for producing coke from coal tar pitch. Conventional coker units include an inlet pipe that are often configured at the bottom of coker unit. As the coke solidifies, the inlet pipe inside the liner sticks to the coke when coke is cooled. Consequently, removal of the inlet pipe from the solidified coke becomes extremely difficult. The liners housed inside the coker unit are generally in cylindrical in shape and the diameter remains the same through-out the length of the liner. As the coke solidifies inside the liner, the hydrocarbons which may be accumulated between the liner and the coker unit may also solidify. Consequently, the removal of the liner from the coker unit becomes difficult as the liner may be jammed due to the solidified coke between the liner and the coker unit. Further, hydrocarbon vapors are generated as the feed is processed to coke in the liner may condense to a liquid state and the liquid hydrocarbons may trickle down in the coker unit. The liquid hydrocarbons may trickle down from the top cover through coker wall. The condensed liquid accumulates in an annular gap between the coker and liner. As the coke inside the liner solidifies when cooled down, the liquid hydrocarbon accumulated in the annular gap also solidifies. Consequently, the solidified hydrocarbons in the annular gap between the coker unit and the liner cause the coker unit and the liner to stick together. Conventional coker units do not comprise of any means for measuring the temperature of the feedstock or the coke inside the liner. Consequently, the quality of coke produced in conventional coker units may often not be of the desired levels.

Accordingly, the present disclosure discloses an apparatus for producing coke from coal tar pitch. The apparatus includes a coker unit defining a chamber, where the coker unit is configured to receive heat energy from a furnace. A liner is removably housed in the coker unit and the liner is defined with a tapered profile from a top end to a bottom end. The taper angle of the tapered profile of the liner ranges from 0.9 degrees to 1.3 degrees from the top end of the liner to the bottom end of the liner. Further, an inlet pipe is configured to feed the coal tar pitch to the internal volume of the liner, and an exhaust hood extends from a closure member and into the coker unit. The exhaust hood is disposed above the liner and a bottom end of the exhaust hood is defined with an inwardly bent profile. The coal tar pitch inside the liner is subjected for heating to a pre-determined temperature under a predetermined pressure for producing the coke. The coker unit also includes an internal pipe positioned inside the liner, where the internal pipe extends from the closure member, substantially along the length of the liner. The internal pipe is configured to house a plurality of thermocouples for measuring temperature of the coke formed inside the liner. Further, a base plate is provided at the bottom end of the liner, where the base plate is defined with a plurality of hooks to facilitate the removal of the liner from the coker unit and to subsequently remove the coke from the liner.

The following paragraphs describe the present disclosure with reference to Figs. 1 to 3.

Fig. 1 illustrates an apparatus (100) for producing coke and Fig. 2 illustrates a process flow diagram of the apparatus (100) of Fig. 1. The apparatus (100) includes a coker unit (1) removably housed in a furnace (19). The furnace (19) enclosing the coker unit (1), heats the coker unit (1) and the material present inside the coker unit (1). The coker unit (1) may be an upright cylindrical metal vessel having high length to diameter ratio and the coker unit (1) may be kept on earth’s surface in a vertical upright position. The cylindrical vessel of the coker unit (1) may include a rib (14). The rib (14) may be provided on the circumference of the coker unit (1) and the rib (14) is used to accommodate and adjust the coker unit (1) inside the furnace (19) while positioning the coker unit (1) inside the furnace (19). The coker unit (1) may removably house a co-axial cylindrical liner (11). The coker unit (1) may be defined by a top end (A1) and a bottom end (B1). The top end (A1) of the coker unit (1) may be provided with a closure member (C) and the bottom end (B1) of the coker unit (1) may be enclosed by a bottom cover flange (2). The closure member (C) may include a body flange (3) and a cover flange (4). The body flange (3) may be an integral part of the cylindrical vessel of the coker unit (1). Further, the cover flange (4) may be removably coupled to the body flange (3) with multiple fasteners. The body flange (3) and the cover flange (4) may be defined with a plurality of threaded holes for accommodating the fasteners. In an embodiment, any known fixtures in the art may be used to fixedly connect the body flange (3) and the cover flange (4). The body flange (3) and the cover flange (4) together enclose the top end (A1) of the coker unit (1). The cover flange (4) may include a first hook (7). The first hook (7) may be used for lifting or separating the cover flange (4) from the body flange (3). The fasteners coupling the body flange (3) and the cover flange (4) may initially be removed and the cover flange (4) may be separated by means of the first hook (7). Further, the cover flange (4) is also provided with an enclosure pipe (6). The enclosure pipe (6) may be positioned adjacent to the first hook (7) and the enclosure pipe (6) may accommodate an inlet pipe (5). The cover flange (4) and the body flange (3) may be defined with a first set of holes (5a) for accommodating the inlet pipe (5). The inlet pipe (5) may extend along a vertical axis of the coker unit (1). The first set of holes (5a) for accommodating the inlet pipe (5) may be defined to lie within the boundaries of the enclosure pipe (6) provided on the cover flange (4). The first set of holes (5a) defined in the body flange (3) and the cover flange (4) may be aligned together for accommodating the inlet pipe (5). Further, a gas inlet pipe (20) may be accommodated by the cover flange (4) by a second hole (20a). The second hole (20a) may also be defined adjacent to the first hook (7). The cover flange (4) and the top end (A1) of the coker unit (1) are defined with an exhaust hood (18).

Further, the exhaust hood (18) may extend from the cover flange (4) of the closure member (C) into the coker unit (1). The exhaust hood (18) may be of a diameter “D1” which is slightly less than the overall diameter of the coker unit (1) and the exhaust hood (18) may be configured by cutting out an internal groove that extends for a pre-determined length from the cover flange (4) of the closure member (C). The exhaust hood (18) is disposed above the liner (11) and a bottom end of the exhaust hood (18) is defined with an inwardly bent profile (18a). In an embodiment, the inwardly bent profile (18a) of the exhaust hood (18) may be chamfer or a fillet. Further, an exhaust pipe (17) may be provided in the exhaust hood (18) of the coker unit (1). A central hole (17a) may be defined in the cover flange (4) of the closure member (C) for accommodating the exhaust pipe (17). The central hole (17a) of the cover flange (4) may connect to the exhaust hood (18) of the body flange (3). The liner (11) is housed below the exhaust hood (18) of the coker unit (1). The liner (11) may lie along the same central axis as that of the coker unit (1) and the cylindrical diameter of the liner (11) may be slightly less than the diameter of the coker unit (1). The liner (11) may be defined with a top end (A) and a bottom end (B). The liner (11) may be configured with a tapered profile and the tapered profile may extend from the top end (A) of the liner (11) to the bottom end (B) of the liner (11). The taper angle of liner may range from 0.9 degrees to 1.3 degrees and is preferably 1.1 degrees. The liner (11) is housed inside the coker unit (1) such that an annular gap (G) is defined between an outer wall of the liner (11) and the inner wall of the coker unit (1). The annular gap (G) between the liner (11) and the coker unit (1) may be minimal at the top end (A) of the liner (11) and the annular gap (G) may gradually increase from the top end (A) to the bottom end (B) of the liner (11) due to the tapered profile of the liner (11). In an embodiment, the diameter “D1” of the exhaust hood (18) may be lesser than the diameter of the liner (11) at the top end (A) of the liner (11). In an embodiment, the diameter “D1” of the exhaust hood (18) may be configured such that the exhaust hood (18) lies within the boundaries of the liner (11) and does not extend to the annular gap (G) defined between the liner (11) and the coker unit (1). The bottom end (B) of the liner (11) is defined with a base (10) and the base (10) is provided with an end plate (16) which encloses the bottom end (B) of the liner (11). The end plate (16) is connected to a support plate (8) and multiple second hooks (9) may be provided on the liner (11).

As shown in FIG. 1, the end plate (16) and the support plate (8) may be fixedly connected to the base (10) of the liner (11) and the second hooks (9) are provided at the bottom of the liner (11) may be used to hang the liner through a lifting means such as crane. Further, at least one internal pipe (13) may be removably housed inside the liner (11) of the coker unit (1). The top end of the internal pipe (13) may extend into the cover flange (4) of the closure member (C) and the bottom end of the internal pipe (13) may be provided with a base plate (12). The base plate (12) and the internal pipe (13) may be connected by thermal joining process such as welding or by any other means known in the art. The internal pipe (13) may be connected at the centre of the base plate (12). The diameter of the base plate (12) may be equal to or slightly lesser than the diameter of the liner (11) at the bottom end (B). The internal pipe (13) along with the base plate (12) may be slid into the liner (11) such that the base plate (12) comes in contact with the end plate (16) of the coker unit (1). The internal pipe (13) and the base plate (12) are configured such that the internal pipe (13) extends along the vertical axis of the coker unit (1) and is housed along the centre of the liner (11). The internal pipe (13) acts as a housing member for accommodating a plurality of thermocouples (21) or any other temperature measuring devices known in the art. The thermocouples (21) housed inside the internal pipe (13) may measure the temperature along the central region of the liner (11). The internal pipe (13) may be supported by a supporting member (15) that extends between the inner walls of the exhaust hood (18). The supporting member (15) may act as a reinforcement member and may hold the internal pipe (13) along the central region of the liner (11). In an embodiment, multiple internal pipes (13), parallel to each other may be configured on the base plate (12) and thermocouples (21) may be accommodated in each of the internal pipes (13). Consequently, temperature at different regions of the liner (11) may suitably be measured.

The production of needle coke from a coal tar pitch is explained in detail below. Feed stock or coal tar pitch may be initially fed into the liner (11) housed inside the coker unit (1) by means of the inlet pipe (5). Coal tar pitch is used as a suitable feed stock for producing high quality coke. However, any other suitable feed stock may also be used for producing coke. Greater aromatic content, lower sulphur and nitrogen content correspond to higher-quality, needle coke suitable for production of commercial electrodes. For creating graphite electrodes that can withstand the ultra-high-power throughput, the needle coke must have a low electrical resistivity and a low coefficient of thermal expansion (CTE). Coal tar pitches are often used as feed stock as they have a high aromatic content exceeding 90 wt.% and a relatively high nitrogen content often exceeding 1 wt.%, but lower sulphur content of approximately 0.5 wt.% or less. Coal tar pitch is initially fed to the coker unit (1) through the inlet pipe (5). The coal tar pitch enters the liner (11) through the inlet pipe (5) from the top and is deposited in the liner (11). The inlet pipe (5) is configured to partially enter the liner (11) at the top end (A) of the liner (11). The inlet pipe (5) barely enters the liners (11) and is configured such that the coal tar pitch enters directly into the liner (11) from the top. Since the coal tar pitch (5) flows vertically downwards from the inlet pipe (5) into the liner (11), the inlet pipe (5) does not get chocked or jammed as in conventional coker units (1) where the feed was supplied from the bottom of the coker unit (1) and the inlet pipe (5) was oriented in the horizontal direction. Further, a provision may be provided in the inlet pipe (5) to mix the steam and or nitrogen along with the coal tar pitch to enable a better flow and avoid any choking in the line.

The coker unit (1) and the liner (11) housed inside the coker unit (1) may be heated by the furnace (19). As the coal tar pitch is fed into the liner (11) of the coker unit (1), the temperature of the coker unit (1) drops. The temperature drop continues till the coal tar pitch completely enters the coker unit (1). The temperature of the coker unit (1) starts rising again after all the coal tar pitch material is fed. Once, the coal tar pitch reaches the required level inside the liner (11), the coal tar pitch may be subjected to high temperature and pressure. The high temperature converts the coal tar pitch into coke and removes the hydrocarbons from the coal tar pitch. This hot liquid coal tar pitch rises within the coker unit (1) and after desired coking time, the pitch is cooled down. Hot pitch typically fills about 70% of the liner (11) volume and is heated from the sidewalls of the coker unit (1) by the furnace (19). The pitch inside the liner (11) may be heated to predetermined temperatures ranging between 4200C to 5500C. The pressure inside the coker unit (1) may be increased or maintained at desired levels by supplying nitrogen gas through the gas inlet pipe (20). Once the coal tar pitch is heated to desired temperatures under desired pressure levels, the coker unit may be maintained at a temperature ranging from 450 0C to 500 0C and the pressure inside the coker unit (1) may be varied from 1.013 bars to 10 bars for a time ranging from 4 hours to 24 hours. The specific properties of the needle coke may be dictated through controlling the properties of the coking process in which an appropriate carbon feedstock may be converted into needle coke. For instance, the temperature of the coal tar pitch inside the liner (11) may be monitored by means of the thermocouples (21) housed inside the internal pipe (13), where the internal pipe (13) extends thorough out the length of the liner (11). The thermocouples (21) or any suitable temperature measuring devices may be connected to a suitable indication means and the temperature of the coal tar pitch throughout the length of the liner (11) may be suitably revealed through the indication means. Based on the indicated values of temperature, the operator may monitor the temperature that the coal tar pitch is subjected to and the operator may suitably vary the heat supplied by the furnace in case of any deviation from the required temperature values. Since the thermocouples (21) housed inside the internal pipe (13) are positioned along the central region of the liner (11), the temperature throughout the coal tar pitch inside the liner (11) can be measured with a greater degree of accuracy. Consequently, the ability of the operator to monitor and control the temperature of the coal tar pitch throughout the liner (11) is also drastically improved.

The above process of heating the coal tar pitch under pressurized conditions, converts the coal tar pitch inside the liner (11) to coke. As the coal tar pitch is processed to coke, the high temperatures and pressures causes the coal tar pitch to expel the hydrocarbon vapours from the coal tar pitch. The hydrocarbon vapours generated during the processing of the coal tar pitch to coke, rise in the coker unit (1) and escape out of the coker unit (1) through the exhaust hood (18) and the exhaust pipe (17) disposed above the liner (11). The hydrocarbon vapours which do not escape through the exhaust hood (18), condense to a liquid state at the top of the coker unit (1). The condensed liquid hydrocarbons drip down from the top of the coker unit (1) into the liner (11). Since, the bottom end of the exhaust hood (18) is defined with an inwardly bent profile (18a), the condensed liquid hydrocarbons often tend to fall back into the liner (11). The bent profile (18a) at the bottom of the exhaust hood (18) ensures that the condensed liquid hydrocarbons do not fall back into the annular gap (G) defined between the liner (11) and the coker unit (1). The configuration of the exhaust hood (18) ensures that the liquid hydrocarbons drip down on the bent profile (18a) of the exhaust hood (18) and fall back into the liner (11). Since the diameter “D1” of the exhaust hood (18) is lesser than the diameter of the liner (11) at the top end (A) of the liner (11), the liquid hydrocarbons fall back into the liner and are prevented from being accumulated in the annular gap (G) between the liner (11) and the coker unit (1). Thus, the above configuration of the exhaust hood (18), effectively prevents the liquid hydrocarbons form being accumulated inside the annular gap (G) defined between the liner (11) and the coker unit (1).

Further, once the coke is formed inside the liner (11) by the above-mentioned process, the coker unit (1) may be allowed to be cooled down to the room temperature. Further, after the coker unit (1) is cooled down, liner (11) may be removed from the coker unit (1) by means of the second hooks (9). An overhead crane or lifting means may be used to lift the coker unit (1) by using the second hooks (9). The liner (11) may be then hanged in an upside-down manner by the second hooks (9) and the coke may be removed from the liner (11) by hammering the liner (11). Since the liner (11) is configured with a tapered profile of 1.1 degrees which extends from the top end (A) of the liner (11) to the bottom end (B) of the liner (11), the removal of the liner (11) from the coker unit (1) becomes easier. The annular gap (G) defined between the outer wall of the liner (11) and the inner wall of the coker unit (1) may be minimal at the top end (A) of the liner (11) and the annular gap (G) may gradually increase from the top end (A) to the bottom end (B) of the liner (11) due to the tapered profile of the liner (11). Therefore, the annular gap (G) at the bottom end (B) of the liner (11) is larger. Any liquid hydrocarbons which may trickle down into the annular gap (G) will get accumulated at the bottom end (B) where the area available is greater than the top end (A). Consequently, the liquid hydrocarbons may get accumulated only at the bottom end (B) and not throughout the length of the annular gap (G) due to which the removal of the liner (11) from the coker unit (1) becomes easier. Further, the orientation of the inlet pipe (5) along the vertical axis and partially into the liner (11), ensures that the inlet pipe (5) does not get stuck with the coke when the coke solidifies. In an embodiment the internal pipe (13) may be used for the removal coke from the liner (11). The coke formed inside the liner (11) may be loosened by vigorously shaking the internal pipe (13) and the coke may further be hammered to be removed from the liner (11).

Fig. 3 illustrates a process flow diagram for manufacturing needle coke, in accordance with an embodiment of the present disclosure. The coal tar pitch which is obtained from the distillation of coal tar is fed into the coker unit (1) to obtain coke or green coke. The coke is formed inside the coker unit (1) in the above-mentioned process. The coke is further subjected to calcination to obtain calcined needle coke. The calcination process may be conducted by any means known in the art.

In an embodiment, the inlet pipe (5) is oriented along the vertical axis and enters from the top of the coker unit (1) reaching just inside the liner (11) so that the coal tar pitch falls into the liner (11) and does not spill outside the liner (11). The above orientation of the liner (11) ensures that there exists no chance of inlet pipe (5) getting stuck with coke when the coke is cooled.

In an embodiment, the tapered configuration of the liner (11) with an increasing annular gap (G) from the top end (A) to the bottom end (B) of the liner (11) ensures that the liner (11) can easily be lifted and taken out from the coker unit (1) with the help of crane. Second hooks (9) provided at the bottom of the liner (11) enable an upside-down removal of the coke deposited inside the liner (11).

In an embodiment, the configuration of the exhaust hood (18) with the bent profile (18a) at the bottom of the exhaust hood (18) ensures that the condensed vapour trickles down into the liner (11) and not in the annular gap (G) between the walls of the coker unit (1) and the liner (11). Consequently, the removal of the liner (11) from the coker unit (1) becomes easier as the negligible amount of condensed vapours would have seeped through and solidified in the annular gap (G).

In an embodiment, the hollow internal pipe (13) with base plate (12) configured inside the liner (11) and thermocouples (21) inserted inside the internal pipe (13) for temperature measurement throughout the length of the coke forming inside the liner (11), assists the operator to monitor and control the temperature inside the liner (11) with a greater degree of accuracy.

Equivalents

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description.

Referral Numerals:

Description Referral numeral
Coker unit 1
Bottom cover plate 2
Body flange 3
Cover flange 4
Closure member C
Inlet pipe 5
First set of holes 5a
Enclosure pipe 6
First hook 7
Support plate 8
Second hooks 9
Liner base 10
Liner 11
Base plate 12
Internal pipe 13
Rib 14
Support members 15
End plate 16
Exhaust pipe 17
Exhaust hood 18
Bent profile of the exhaust hood 18a
Furnace 19
Gas inlet pipe 20
Second set of holes 20a
Thermocouples 21

Claims:1. An apparatus (100) for producing coke from coal tar pitch, the apparatus comprising (100):
a coker unit (1) defining a chamber, wherein the coker unit (1) is configured to receive heat energy from a furnace (19);
a liner (11) removably housed in the coker unit (1), wherein the liner (11) is defined with a tapered profile from a top end (A) to a bottom end (B);
an inlet pipe (5) extending along a vertical axis of the coker unit (1) into an internal volume of the liner (11) from the top end (A) of the liner (11), wherein the inlet pipe (5) is configured to feed the coal tar pitch to the internal volume of the liner (11);
wherein, the coal tar pitch inside the liner (11) is subjected for heating to a pre-determined temperature under a predetermined pressure for producing the coke.

2. The apparatus (100) as claimed in claim 1, comprising a closure member (C) enclosing an upper portion of the coker unit (1).

3. The apparatus (100) as claimed in claim 2, wherein the closure member (C) is defined with an enclosure (6) to accommodate the inlet pipe (5).

4. The apparatus (100) as claimed in claim 1, wherein taper angle of the tapered profile of the liner (11) ranges from 0.9 degrees to 1.3 degrees from the top end (A) of the liner (11) to the bottom end (B) of the liner (11).

5. The apparatus (100) as claimed in claim 1, comprising an exhaust hood (18) extending from closure member (C) into the coker unit (1).

6. The apparatus (100) as claimed in claim 5, wherein the exhaust hood (18) is disposed above the liner (11) and a bottom end of the exhaust hood (18) is defined with an inwardly bent profile (18a).

7. The apparatus (100) as claimed in claim 1, comprising an internal pipe (13) positioned inside the liner (11), wherein the internal pipe (13) extends from the closure member (C), substantially along the length of the liner (11).

8. The apparatus (100) as claimed in claim 1, wherein the internal pipe (13) is configured to house a plurality of thermocouples for measuring temperature of the coke formed inside the liner (11).

9. The apparatus (100) as claimed in claim 1, comprising a end plate (16) provided at the bottom end of the liner (11), wherein the end plate (16) is defined with a plurality of hooks (9) to facilitate the removal of the liner (11) from the coker unit (1) and to subsequently remove the coke from the liner (11).

10. The apparatus (100) as claimed in claim 1, wherein the pre-determined temperature for heating the coal tar pitch inside the liner (11) ranges from 420 0C to 550 0C.

11. The apparatus (100) as claimed in claim 1, wherein the pre-determined pressure inside the liner (11) ranges from 1.013 bar to 10 bar.

12. A method of assembling an apparatus (100) as claimed in claim 1, for producing coke from coal tar pitch, the method comprising:
removably accommodating the liner (11) inside the coker unit (1), wherein the liner (11) is defined with a tapered profile from a top end (A) to a bottom end (B);
wherein, the coker unit (1) is housed in the furnace (19) and the furnace (19) heats the coker unit (1);
positioning the inlet pipe (5) such that the inlet pipe (5) extends along a vertical axis of the coker unit (1) into internal volume of the liner (11) from the top end (A) of the liner (11), wherein the inlet pipe (5) is configured to feed the coal tar pitch into the internal volume of the liner (11);
wherein, the coal tar pitch inside the liner (11) is subjected for heating to the pre-determined temperature under the predetermined pressure for producing the coke.

13. The method as claimed in claim 12 comprises, enclosing an upper section of the coker unit (1) by the closure member (C).

14. The method as claimed in claim 12, wherein the liner (11) is tapered at an angle ranging from 0.9 degrees to 1.3 degrees from the top end (A) of the liner (11) to the bottom end (B) of the liner (11).

15. The method as claimed in claim 12 comprises, configuring the exhaust hood (18) to extend from the closure member (C) into the coker unit (1).

16. The method as claimed in claim 12 comprises, introducing inside the liner (11), the internal pipe (13), wherein the internal pipe (13) extends from the closure member (C), substantially along the length of the liner (11).

17. The method as claimed in claim 16 comprises, configuring the plurality of thermocouples inside the internal pipe (13) for measuring the temperature of the coke formed inside the liner (11).

18. The method as claimed in claim 17 comprises, configuring the plurality of hooks (9) to the end plate (16) provided at the bottom end (B) of the liner (11), to facilitate the removal of the liner (11) from the coker unit (1) and to subsequently remove the coke from the liner (11).

19. The method as claimed in claim 12, wherein the coal tar pitch inside the liner (11) is heated to a temperature ranging from 420 0C to 550 0C.

20. The method as claimed in claim 12, wherein the pre-determined pressure inside the liner (11) ranges from 1.013 bars to 10 bars.