TECHNICAL FIELD
The present disclosure relates to the field of metallurgy. The present disclosure particularly
relates to briquette composition comprising coke fines and composite binder comprising
ordinary portland cement, bentonite, and pregel starch. The present disclosure further relates
5 to briquette obtained from said briquette composition and to the processes of preparing the
briquette composition and the briquette, and application thereof.
BACKGROUND OF THE DISCLOSURE
High-carbon ferrochrome is a popular chrome-based ferroalloy used to manufacture stainless
10 steel and high-chromium steels. The high-carbon ferrochrome is made by reducing chrome ore
with coke and coal. However, the recent surge in the prices of coke has significantly increased
the cost of producing ferrochrome thus making the production of ferrochrome uneconomical.
Attempts are made to use coke fines as reductant to produce ferrochrome alloy. However,
15 agglomeration of coke fines is noted as a huge challenge having constraints with respect to
thermal stability and cold crushing strength.
Agglomerating coke fines to produce briquettes was attempted. However, processes involved
in such attempts require high-temperature and complicated curing steps, making the process
20 complex, expensive, and not economically viable.
Additionally, cold-bonded briquetting processes have already been tried mainly for
metallurgical wastes comprising iron, chromium, manganese, and non-ferrous metallurgical
mixtures. However, these processes depended on cementitious and slag-generating binding
25 materials with a complicated and lengthy curing process for producing cold-bonded briquettes,
which made the process prohibitively expensive.
Thus, there are limitations in ferrochrome preparation and effective utilization of coke fines
which are abundantly produced.
30
The present disclosure addresses said limitations and provides a two-fold advantage in terms
of effective utilization of waste material such as coke fines for making briquettes and economic
production of ferroalloy.
3
STATEMENT OF THE DISCLOSURE
Accordingly, the present disclosure relates to an improved briquette composition comprising
coke fines and composite binder comprising ordinary portland cement, bentonite, and pregel
starch.
5
The present disclosure further relates to a process of preparing the briquette composition, said
process comprising, mixing the coke fines, and the composite binder, optionally along with
water to obtain the briquette composition.
10 The present disclosure further relates to a briquette obtained by the briquette composition. The
briquette has improved properties, such as coke reactive index, cold strength after reaction, and
cold compressive strength.
The present disclosure further relates to a process for producing the briquette, comprising:
15 blending coke fines, composite binder, and solvent to obtain the composition, followed by
molding; pressing the molded composition, and curing the pressed composition to obtain the
briquette.
The present disclosure further relates to a process for producing ferroalloy, comprising
20 providing the briquette and raw material(s) to a furnace, followed by smelting to obtain the
ferroalloy. The process of producing the ferroalloy according to the present disclosure is
economical when compared to conventional processes.
BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
25 In order that the present disclosure may be readily understood and put into practical effect,
reference will now be made to exemplary embodiments as illustrated with reference to the
accompanying figures. The figures together with the detailed description below, are
incorporated in and form part of the specification and serve to further illustrate the
embodiments and explain various principles and advantages, where:
30
FIGURE 1 describes a plot illustrating size distribution of coke fines employed in the present
disclosure.
FIGURE 2 describes a plot illustrating X-ray diffraction analysis (XRD) pattern for coke fines
employed in the present disclosure.
4
FIGURE 3A illustrates scanning electron microscope (SEM) micrograph of coke fines
employed in the present disclosure.
FIGURE 3B illustrates Energy-dispersive X-ray spectroscopy (EDS) analysis of coke fines
employed in the present disclosure.
5 FIGURE 4 describes a plot illustrating thermogravimetric analysis (TGA) of organic and
inorganic binders.
FIGURE 5A describes a plot illustrating cold compressive strength (CCS) of pillow shaped
briquette of the present disclosure and other briquettes (comparative briquettes).
FIGURE 5B describes a plot illustrating drops test results of pillow shaped briquette of the
10 present disclosure and other briquettes (comparative briquettes).
FIGURE 6 describes an image of blending machine employed for the preparation of composite
binder.
FIGURE 7 describes a graphical illustration of the production of briquette according to the
present disclosure.
15 FIGURE 8A describes a graphical illustration of roller pressing of the briquette composition.
FIGURE 8B describes an image of the briquette of the present disclosure and its dimension.
FIGURE 9 describes a plot illustrating cold compressive strength (CCS) of pillow shape
briquette.
FIGURE 10 describes a plot illustrating the resistivity of coke briquette of the present
20 disclosure (C+PS+Be+Ce), cokes fines, a combination of coke fines and pregel starch (C+PS),
a combination of coke fines and bentonite (C+Be) and a combination of coke fines, bentonite
and cement (C+Be+Ce).
FIGURE 11 describes contact angle, wherein- A) illustrates contact angle of briquette of the
present disclosure (coke briquette); and B) illustrates contact angle of coke fines.
25 FIGURE 12 describes a plot illustrating thermogravimetric analysis (TGA) patterns for
briquette of the present disclosure (coke briquettes) and binders.
FIGURE 13 describes back-scattered images of coke fines (A) and briquette of the present
disclosure (coke briquette) (B), identified in scanning electron microscopy analysis (SEM).
FIGURE 14 describes a plot illustrating energy dispersive X-ray spectroscopy (EDS) spectra
30 of the briquette of the present disclosure (coke briquette) measured in scanning electron
microscopy analysis (SEM).
FIGURE 15 (A to J) describe plots illustrating X-ray photoelectron spectroscopy (XPS) spectra
of briquette of the present disclosure (coke briquette).
5
FIGURE 16 describes a plot illustrating cold compressive strength (CCS) and weight loss of
briquette of the present disclosure (coke briquette) vis-a-vis varied temperatures.
FIGURE 17: describes plots illustrating hot-stage microscopic examination of coke fines (‘A’
and ‘B’) and briquette of the present disclosure (‘C’ and ‘D’).
5 FIGURE 18 describes a plot illustrating the weight loss of ULP coke and briquette of the
present disclosure (coke briquette) derived from thermogravimetric analysis (TGA).
FIGURE 19: describes an image of submerged arc furnace equipment employed for smelting.
DETAILED DESCRIPTION OF THE DISCLOSURE
10 Unless otherwise defined, all terms used in the disclosure, including technical and scientific
terms, have meaning as commonly understood by one of ordinary skill in the art to which this
disclosure belongs. By means of further guidance, term definitions are included for better
understanding of the present disclosure.
15 As used herein, the singular forms ‘a’, ‘an’ and ‘the’ include both singular and plural referents
unless the context clearly dictates otherwise.
The term ‘comprising’, ‘comprises’ or ‘comprised of’ as used herein are synonymous with
‘including’, ‘includes’, ‘containing’ or ‘contains’ and are inclusive or open-ended and do not
20 exclude additional, non-recited members, elements or method steps.
The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed
within the respective ranges, as well as the recited endpoints.
25 The term ‘about’ as used herein when referring to a measurable value such as a parameter, an
amount, a temporal duration, and the like, is meant to encompass variations of ±10% or less,
preferably ±5% or less, more preferably ±1% or less and still more preferably ±0.1% or less of
and from the specified value, insofar such variations are appropriate to perform the present
disclosure. It is to be understood that the value to which the modifier ‘about’ refers is itself also
30 specifically, and preferably disclosed.
Reference throughout this specification to ‘some embodiments’, ‘one embodiment’, or ‘an
embodiment’ means that a particular feature, structure, or characteristic described in
connection with the embodiment may be included in at least one embodiment of the present
6
disclosure. thus, the appearances of the phrases ‘in some embodiments’, ‘in one embodiment’
or ‘in an embodiment’ in various places throughout this specification may not necessarily all
refer to the same embodiment. It is appreciated that certain features of the disclosure, which
are for clarity, described in the context of separate embodiments, may also be provided in
5 combination in a single embodiment. Conversely, various features of the disclosure, which are,
for brevity described in the context of a single embodiment, may also be provided separately
or in any suitable sub-combination.
The term ‘coke strength after reaction (CSR)’ as used herein refers to hot strength of the coke
10 briquette, which signifies degradation potential of the briquette in submerged arc furnace.
The terms “cold crushing strength” or “cold compressive strength” are interchangeably
employed, and they refer to the ability of the coke briquette to resist failure or breaking under
compressive load at varied temperatures.
15
The term “thermal stability” as used herein refers to the ability of coke briquette to resist the
action of heat energy by maintaining its mechanical properties like strength, toughness, or
elasticity at a given temperature.
20 The term “coke reactive index” as used herein refers to the percentage loss in weight for the
total sample mass charged in the furnace.
The term “Bulk density” as used herein refers to the weight of a volume unit of powder and is
usually expressed in g/cm3
, kg/m3
, or g/100 ml.
25
The term “True density” as used herein refers to the quotient of mass over the volume of a
sample, without considering pores in the material (true volume).
The present disclosure relates to an improved briquette composition obtained by effectively
30 utilizing coke fines.
In some embodiments of the present disclosure, the briquette composition comprises coke
fines; and composite binder comprising ordinary portland cement, bentonite, and pregel starch.
7
In some embodiments of the present disclosure, the briquette composition comprises coke fines
in an amount ranging from about 90 wt.% to 95 wt.%, including all the values in the range, for
instance, 90.1 wt.%, 90.2 wt.%, 90.3 wt.%, 90.4 wt.% and so on and so forth, up until 95 wt.%,
and including subranges of the range 90 wt.% to 95 wt.%. In an embodiment, the briquette
5 composition comprises coke fines in an amount of about 90 wt.%, about 91 wt.%, about 92
wt.%, about 93 wt.%, about 94 wt.% or about 95 wt.%.
In some embodiments of the present disclosure, the coke fines of the composition has particle
size ranging from about 1000 µm to 5000 µm, including all the values in the range, for instance,
10 1001 µm, 1002 µm, 1003 µm and so and so forth, up until 5000 µm, and including subranges
of the range 1000 µm to 2000 µm, 2000 µm to 3000 µm, 3000 µm to 4000 µm, 4000 µm to
5000 µm. In an embodiment, Figure 1 describes a plot illustrating the size distribution of the
coke fines.
15 In some embodiments of the present disclosure, the coke fines of the composition comprises
about 0.5% to 1.5 % of CaO, about 25% to 35 % of SiO2, about 0.5% to 0.8 % of Sulphur (S),
about 9% to 13 % of Fe(T), about 25% to35% of Cr2O3, about 0.011% to 0.016% of
Phosphorous(P), about 1% to 3 % of MgO, about 0.4% to 0.6% of MnO, about 20% to 30% of
Al2O3, about 0.1% to 0.4% of TiO2, about 78% to 82% of fixed carbon (FC), about 5.8% to
20 6.2% of volatile material (VM) and 13% to 15% of ash content. In an embodiment, Figure 2
describes a plot illustrating X-ray diffraction analysis (XRD) pattern of the coke fines. In an
embodiment, Figure 3 describes energy-dispersive X-ray spectroscopy (EDS) analysis of the
coke fines.
25 In some embodiments of the present disclosure, the briquette composition comprises composite
binder in an amount ranging from about 1 wt% to 10 wt%, including all the values in the range,
for instance, 1.1 wt.% 1.2 wt.%, 1.3 wt.%, 1.4 wt.% and so on and so forth, up until 10 wt.%,
and including subranges of the range 1 wt.% to 10 wt.%. In an embodiment of the present
disclosure, the briquette composition comprises composite binder in an amount of about 1
30 wt.%, about 2 wt.%, about 3 wt.%, about 4 wt.%, about 5 wt.%, about 6 wt.%, about 7 wt.%,
about 8 wt.%, about 9 wt.%, or about 10 wt.%.
In some embodiments of the present disclosure, the briquette composition comprises coke fines
and composite binder in a ratio 9:1.
8
In some embodiments of the present disclosure, the composite binder comprises ordinary
portland cement in an amount ranging from 2 wt.% to 6 wt.%, including all the values in the
range, for instance, 2.1 wt.%, 2.2 wt.%, 2.3 wt.%, 2.4 wt.% and so on and so forth, up until 6
wt.%, and including subranges of the range 2 wt.% to 6 wt.%. In an embodiment of the present
5 disclosure, the composite binder comprises ordinary Portland cement in an amount of about 2
wt.%, about 3 wt.%, about 4 wt.%, about 5 wt.% or about 6 wt.%.
In some embodiments of the present disclosure, the composite binder comprises bentonite in
an amount ranging from about 1 wt.% to 4 wt.% including all the values in the range, for
10 instance, 1.1 wt.%, 1.2 wt.%, 1.3 wt.%, 1.4 wt.% and so on and so forth, up until 4 wt.%, and
including subranges of the range 1 wt.% to 4 wt.%. In an embodiment, the composite binder
comprises bentonite in an amount of about 1 wt.%, about 2 wt.%, about 3 wt.% or about 4
wt.%.
15 In some embodiment of the present disclosure, the composite binder comprises pregel starch
in an amount ranging from about 2 wt.% to 6 wt.%, including all the values in the range, for
instance, 2.1 wt.%, 2.2 wt.%, 2.3 wt.%, 2.4 wt.% and so on and so forth, up until 6 wt.%, and
including subranges of the range 2 wt.% to 6 wt.%. In an embodiment of the present disclosure,
the composite binder comprises pregel starch in an amount of about 2 wt.%, about 3 wt.%,
20 about 4 wt.%, about 5 wt.% or about 6 wt.%.
In an exemplary embodiment, the composite binder of the composition comprises 2 wt.% to 6
wt.% of ordinary portland cement, about 1 wt.% to 4 wt.% of bentonite and about 2 wt.% to 6
wt.% of pregel starch.
25
In an exemplary embodiment of the present disclosure, the composite binder comprises
ordinary portland cement, bentonite, and pregel starch in a ratio ranging from about 2:1:2 to
3:2:3, preferably of about 4:2:4.
30 In an exemplary embodiment of the present disclosure, the composite binder comprises
ordinary portland cement, bentonite, and pregel starch in a ratio of about 4:2:4.
In some embodiments of the present disclosure, the composite binder in the composition has
particle size ranging from about 30 µm to 45 µm, including all the values in the range, for
9
instance, 30.1 µm, 30.2 µm, 30.3 µm, 30.4 µm and so on and so forth, up until 45 µm, and
including subranges of the range 30 µm to 45 µm.
In some embodiments of the present disclosure, the briquette composition additionally
5 comprises moisture content ranging from about 8% to 10%, including all the values in the range
for instance from 8.1%, 8.2%, 8.3%, 8.4% and so on and so forth, up until 10 %, and including
subranges of the range 8% to 10%. In an embodiment, the briquette composition additionally
comprises a moisture content of about 8%, about 9% or about 10%.
10 In an exemplary embodiment of the present disclosure, the briquette composition comprises
about 90 wt.% to 95 wt.% of the coke fines and about 1 wt.% to 10 wt.% of the composite
binder.
In another exemplary embodiment of the present disclosure, the briquette composition
15 comprises about 90 wt.% to 95 wt.% of the coke fines, about 1 wt.% to 10 wt.% of the
composite binder and about 8% to 10% of moisture.
The present disclosure further relates to a process for preparing the briquette composition as
described above.
20
While the subsequent embodiments focus on the process of preparing the briquette
composition, the features and characteristics of the briquette composition are as described by
any of the embodiments above. For the sake of brevity, and avoiding repetition, each of those
embodiments is not being reiterated here again. However, each of the said embodiments
25 completely falls within the purview of the process of preparing the briquette composition.
In some embodiments of the present disclosure, the process of preparing the briquette
composition comprises- mixing the coke fines and the composite binder, optionally along with
water to obtain the briquette composition.
30
In some embodiments of the present disclosure, in the process of preparing the briquette
composition, the mixing is carried out at a temperature ranging from about 24℃ to 27℃,
including all the values in the range, for instance, 24.1℃, 24.2℃, 24.3℃, 24.4℃ and so on
and so forth, up until 27℃, and including subranges of the range 24℃ to 27℃. In an
10
embodiment, the mixing is carried out for a duration ranging from about 0.5 minutes to 3
minutes, including all the values in the range for instance 0.5 minutes, 0.6 minutes, 0.7 minutes,
0.8 minutes, and so on and so forth, up until 3 minutes, and including subranges of the range
0.5 minutes to 3 minutes.
5
In an exemplary embodiment of the present disclosure, the process of preparing the briquette
composition comprises- mixing about 90 wt.% to 95 wt.% of the coke fines and about 1 wt.%
to 10 wt.% of the composite binder, at a temperature ranging from about 24°C to 27°C, for a
duration ranging from about 0.5 minutes to 3 minutes to obtain the briquette composition.
10
In another exemplary embodiment of the present disclosure, the process of preparing the
briquette composition comprises- mixing about 90 wt.% to 95 wt.% of the coke fines, about 1
wt.% to 10 wt.% of the composite binder and about 8% to 10% of water or moisture, at a
temperature ranging from about 24°C to 27°C, for a duration ranging from about 0.5 minutes
15 to 3 minutes, to obtain the briquette composition.
The process of preparing the briquette composition according to the present disclosure is
simple, economical, and environmentally friendly.
20 The present disclosure further relates to a briquette obtained by the briquette composition
defined above.
While the subsequent embodiments focus on the briquette, the features and characteristics of
the briquette composition employed for generating briquettes are as described by any of the
25 embodiments above. For the sake of brevity, and avoiding repetition, each of those
embodiments is not being reiterated here again. However, each of the said embodiments of
briquette composition completely falls within the purview of the briquette described below.
In some embodiments of the present disclosure, moulded, pressed, and cured form of the
30 briquette composition described above is the briquette. The briquette obtained from the
briquette composition has improved properties.
11
In some embodiments of the present disclosure, the briquette has moisture content ranging from
about 2% to 6%, including all the values in the range, for instance, 2.1%, 2.2%, 2.3%, 2.4%
and so on and so forth, up until 6%, and including subranges of the range 2% to 6%.
5 In some embodiments of the present disclosure, the briquette has electrical resistivity ranging
from about 10 m𝞨.m to 15 m𝞨.m including all the values in the range, for instance, 10.1
m𝞨.m, 10.2 m𝞨.m, 10.3 m𝞨.m, 10.4 m𝞨.m and so on and so forth, up until 15 m𝞨.m and
including subranges of the range 10 m𝞨.m to 15 m𝞨.m. In an embodiment, the briquette has
electrical resistivity of about 10 m𝞨.m, about 11 m𝞨.m, about 12 m𝞨.m, about 13 m𝞨.m,
10 about 14 m𝞨.m, or about 15 m𝞨.m. In an embodiment, Figure 10 describes electrical resistivity
of the briquette of the present disclosure in comparison with coke fines (C), combination of
coke fines and pregel starch (C+PS), coke fines and bentonite (C+Be) and combination of coke
fines, bentonite and cement (C+Be+Ce). Data in Figure 10 shows that the briquette of the
present disclosure has improved electrical resistivity when compared to other components
15 described therein. The electrical resistiveness represents the most important property of a
reducing agent in the submerged arc furnace. For heat distribution, high and optimum
resistivity is required. The observed value of resistivity of coke briquette in the range of 10
m𝞨.m to 15 m𝞨.m is very much preferred in actual furnace conditions.
20 In some embodiments of the present disclosure, the briquette comprises ash content ranging
from about 12% to 25 %, including all the values in the range, for instance, 12.1%, 12.2%,
12.3%, 12.4% and so on and so forth, up until 25%, and including subranges of the range 12%
to 25%. In an embodiment, the briquette has an ash content of about 12%, about 13%, about
14%, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, about 21%, about
25 22%, about 23%, about 24%, or about 25%.
In some embodiments of the present disclosure, the briquette has volatile material ranging from
about 7% to 13%, including all the values in the range, for instance, 7.1%, 7.2%, 7.3%, 7.4%
and so on and so forth, up until 13%, and including subranges of the range 7% to 13%. In an
30 embodiment, the briquette has volatile material of about 7%, about 8%, about 9%, about 10%,
about 11%, about 12%, or about 13%,
12
In some embodiments of the present disclosure, the briquette has fixed carbon ranging from
about 67% to 78%, including all the values in the range, for instance, 67.1%, 67.2%, 67.3%,
67.4% and so on and so forth, up until 78, and including subranges of the range 67% to 78%.
In an embodiment, the briquette has fixed carbon of about 67%, about 68%, about 69%, about
5 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, or
about 78%.
In some embodiments of the present disclosure, the briquette has sulphur ranging from about
0.1 to 0.5%. In an embodiment, the briquette has sulphur content of about 0.1%, about 0.2%,
10 about 0.3%, about 0.4% or about 0.5%.
In some embodiments of the present disclosure, the briquette has phosphorous ranging from
about 0.014% to 0.019%. In an embodiment, the briquette has phosphorous of about 0.014%,
about 0.015%, about 0.016%, about 0.017%, about .018%, or about 0.019%.
15
In some embodiments of the present disclosure, the briquette has SiO2 ranging from about 24%
to 33%, including all the values in the range, for instance, 24.1%, 24.2%, 24.3%, 24.4% and so
on and so forth, up until 33%, and including subranges of the range 24% to 33%. In an
embodiment, the briquette has SiO2 of about 24%, about 25%, about 26%, about 27%, about
20 28%, about 29%, about 30%, about 31%, about 32%, or about 33%,
In some embodiments of the present disclosure, the briquette has Al2O3 ranging from about
12% to 16%, including all the values in the range, for instance, 12.1%, 12.2%, 12.3%, 12.4%
and so on and so forth, up until 16%, and including subranges of the range 12% to 16%. In an
25 embodiment, the briquette has Al2O3 of about 12%, about 13%, about 14%, about 15% or about
16 %.
In some embodiments of the present disclosure, the briquette has Fe2O3 ranging from about 9%
to 14%, including all the values in the range, for instance, 9.1%, 9.2%, 9.3%, 9.4% and so on
30 and so forth, up until 14%, and including subranges of the range, 9% to 14%. In an embodiment,
the briquette has Fe2O3 of about 9%, about 10%, about 11%, about 12%, about 13% or about
14%.
13
In some embodiments of the present disclosure, the briquette has CaO ranging from about 4%
to 10%, including all the values in the range, for instance, 4.1%, 4.2%, 4.3%, 4.4% and so on
and so forth, up until 10%, and including subranges of the range 4% to 10%. In an embodiment,
the briquette has CaO of about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, or
5 about 10 %.
In some embodiments of the present disclosure, the briquette has Cr2O3 ranging from about
24% to 35%, including all the values in the range, for instance, 24.1%, 24.2%, 24.3%, 24.4%
and so on and so forth, up until 35%. In an embodiment, the briquette has Cr2O3 of about 24%,
10 about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%,
about 33%, about 34%, or about 35%.
Accordingly, the briquette of the present disclosure has fixed carbon of about 67% to 78%, S
of about 0.1% to 0.5 %, P of about 0.014% to 0.019%, SiO2 of about 24% to 33%, Al2O3 of
15 about 12% to 16 %, Fe2O3 of about 9% to 14%, CaO of about 4% to 10%, and Cr2O3 of about
24% to 35%. In an embodiment, Figure 14 provides Energy-dispersive X-ray spectroscopy
(EDS) data of the briquette of the present disclosure measured in scanning electron microscopy.
In an embodiment, Figure 15 provides X-ray photoelectron spectroscopy (XPS) analysis data
of the briquette of the present disclosure.
20
In some embodiments of the present disclosure, the briquette is thermally stable up to
temperature ranging from about 1300 °C to 1400 °C, including all the values in the range, for
instance, 1300 °C, 1301 °C, 1302 °C, 1303 °C and so on and so forth, up until 1400 °C, and
including subranges of the range 1300 °C to 1400 °C.
25
In some embodiments of the present disclosure, the briquette has coke reactive index (CRI)
ranging from about 32% to 45%, including all the values in the range, for instance, 32.1%,
32.2%, 32.3%, 32.4% and so on and so forth, up until 45%, and including subranges of the
range 32% to 45%. In an embodiment, the briquette has coke reactive index (CRI) of about
30 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about
40%, about 41%, about 42%, about 43%, about 44% or about 45%.
In some embodiments of the present disclosure, the briquette has coke strength after reaction
(CSR) ranging from about 18% to 25%, including all the values in the range, for instance,
14
18.1%, 18.2%, 18.3%, 18.4% and so on and so forth, up until 25%, and including subranges of
the range 18% to 25%. In an embodiment, the briquette has coke strength after reaction (CSR)
of about 18%, about 19%, about 20%, about 21%, about 22%, about 23%, about 24% or about
25%.
5
In some embodiments of the present disclosure, the briquette has porosity ranging from about
32% to 39%, including all the values in the range, for instance, 32.1%, 32.2%, 32.3%, 33.4%
and so on and so forth, up until 36%, and including subranges of the range 32% to 39%. In an
embodiment, the briquette has porosity of about 32%, about 33%, about 34%, about 35%,
10 about 36%, about 37%, about 38% or about 39%.
In some embodiments of the present disclosure, the briquette has cold compressive strength
(CCS) ranging from about 98 kgf/briquette to 700 kgf/briquette including all the values in the
range, for instance, 98.1 kgf/briquette, 98.2 kgf/briquette, 98.3 kgf/briquette, 98.4 kgf/briquette
15 and so on and so forth, up until 700 kgf/briquette, and including subranges of the range 98
kgf/briquette to 700 kgf/briquette. In an embodiment, Figures 5A and 9 describe cold
compressive strength (CCS) of the briquette (coke briquette) of the present disclosure.
In some embodiments of the present disclosure, the briquette has bulk density (B.D.) ranging
20 from about 1.1 gm/cc to 1.4 gm/cc, including all the values in the range, for instance 1.1 gm/cc,
1.2 gm/cc, 1.3 gm/cc, 1.4 gm/cc.
In some embodiments of the present disclosure, the briquette has true density (T.D.) ranging
from about 1.5 gm/cc to 2.0 gm/cc, including all the values in the range, for instance 1.5 gm/cc,
25 1.6 gm/cc, 1.7 gm/cc, 1.8 gm/cc, 1.9 gm/cc, 2.0 gm/cc.
In some embodiments of the present disclosure, the briquette has contact angle ranging from
about 42˚ to 46˚ including all the values in the range, for instance, 42.1˚, 42.2˚, 42.3˚, 42.4˚ and
so on and so forth, up until 46˚, and including subranges of the range 42˚ to 46˚. In an
30 embodiment, the briquette has contact angle of about 42˚, about 43˚, about 44˚, about 45˚ or
about 46˚. In an embodiment, figure 11 A and B illustrates the contact angle of the briquette
(coke briquette) of the present disclosure and coke fines respectively. Data in Figure 11 shows
a lower contact angle for the briquette when compared to coke fines, which indicates better
binding power of briquette in comparison with coke fines.
15
Accordingly, the briquette of the present disclosure has coke reactive index of about 32% to
45%, cold strength after reaction of about 18 to 25%, porosity of about 32 to 39, cold
compressive strength of about 98 kgf/briquette to 700 kgf/briquette and contact angle of about
42° to 46°.
5
In some embodiments of the present disclosure, the briquette is intact and stable upon drops
ranging from about 60 to 120, including all the values in the range, for instance 61 drops, 62
drops, 63 drops, 64 drops and so and so forth, up until 120 drops, and including subranges of
the range 60 to 120 drops, 80 to 100 drops, 100 to 120 drops according to drop test. In an
10 embodiment, Figure 5B demonstrates the stability of the briquette (coke briquette) of the
present disclosure as per the drops test result. The data in Figure 5B shows that the briquette
of the present disclosure is stable and able to withstand drops in the range of 60 to 120 when
compared to other components mentioned therein.
15 In an embodiment, the briquette of the present disclosure is stable and able to withstand drops
greater than 100.
In an embodiment, the briquette of the present disclosure is stable and able to withstand drops
in the range of 80 to100.
20
The inventors of the present disclosure have particularly identified that the briquettes obtained
from the composition comprising cokes and composite binder comprising ordinary portland
cement, bentonite, and pregel starch exhibits improved properties, such as cold crushing
strength or cold compressive strength, coke reactive index and coke strength after reaction. The
25 briquette of the present disclosure possesses high thermal strength, i.e., the briquette is capable
of withstanding degradation at high temperatures. The inventors also identified that employing
composite binder comprising combination of ordinary portland cement, bentonite and pregel
starch with coke fines, effectively agglomerates coke fines and leads to the formation of
briquettes with said improved properties.
30
The present disclosure further relates to a process for producing the briquette as described
above.
16
While the subsequent embodiments focus on the process of preparing the briquette, the features
and characteristics of the briquette are as described by any of the embodiments above. For the
sake of brevity, and to avoid repetition, each of those embodiments is not being reiterated here
again. However, each of the said embodiments completely falls within the purview of the
5 process of preparing the briquette.
In some embodiments of the present disclosure, the process of preparing the briquette
comprises:
• blending of coke fines, composite binder, and solvent to obtain the composition,
10 followed by molding;
• pressing the molded composition; and
• curing the pressed composition to obtain the briquette.
In some embodiments of the present disclosure, in the process of preparing the briquette, the
15 blending is carried out at a temperature ranging from about 24℃ to 27℃, including all the
values in the range, for instance, 24.1 ℃, 24.2 ℃, 24.3 ℃, 24. 4 ℃ and so on and so forth, up
until 27 ℃, and including subranges of the range 24 ℃ to 27 ℃. In an embodiment, the
blending is carried out for a duration ranging from about 1 minutes to 3 minutes, including all
the values in the range, for instance, 1.1 minutes, 1.2 minutes, 1.3 minutes, 1.4 minutes and so
20 on and so forth.
In some embodiments of the present disclosure, in the process of preparing the briquette, the
solvent employed is water. In an embodiment, the solvent is in an amount ranging from about
8% to 10 %, including all the values in the range, for instance, 8.1%, 8.2%, 8.3%, 8.4% and so
25 on and so forth, up until 10%. In an embodiment, the solvent is in an amount of about 8%,
about 9% or about 10%.
In some embodiments of the present disclosure, in the process of preparing the briquette, the
blended mixture is held for a duration of about 30 to 60 seconds including all the values in the
30 range, for instance, 31 seconds, 32 seconds and so on and so forth up until 60 seconds before
pressing and then released for pressing for a duration of about 1 to 10 seconds including all the
values in the range, for instance, 1 second, 2 seconds, 3 seconds, 4 seconds and so on and so
forth up until 10 seconds.
17
In some embodiments of the present disclosure, in the process of preparing the briquette, the
pressing is carried out for a duration ranging from about 0.5 minutes to 2 minutes, including
all the values in the range, for instance, 0.5 minutes, 0.6 minutes, 0.7 minutes, 0.8 minutes and
so on and so forth, up until 2 minutes, and including subranges of the range 0.5 minutes to 2
5 minutes. In an embodiment, the pressing is carried out at a compressive force ranging from
about 5 tf to 50 tf, including all the values in the range, for instance, 5.1 tf, 5.2 tf, 5.3 tf, 5.4 tf
and so on and so forth, up until 50 tf. In an embodiment, the pressing is carried out by a
technique selected from a group comprising roller pressing, hydraulic pressing, extrusion
machine, and combinations thereof.
10
In some embodiments of the present disclosure, in the process of preparing the briquette, the
curing is carried out at a temperature ranging from about 24℃ to 30℃, including all the values
in the range, for instance, 24.1 ℃, 24.2 ℃, 24.3 ℃, 24.4 ℃ and so on and so forth, up until
30℃, and including subranges of the range 24 ℃ to 30 ℃. In an embodiment, the curing is
15 carried out for a duration ranging from about 70 hours to 200 hours, including all the values in
the range, for instance, 71 hours, 72 hours, 73 hours, 74 hours and so on and so forth, up until
200 hours, and including subranges of the range 70 hours to 200 hours.
In an exemplary embodiment, the process of preparing the briquette comprises20 - blending the coke fines, the composite binder and the solvent at a temperature ranging
from about 24℃ to 27℃, for a duration ranging from about 1 minute to 3 minutes,
followed by molding;
- pressing the molded composition at force ranging from about 5tf to 50 tf, for a duration
ranging from about 0.5 minutes to 2 minutes; and
25 - curing the pressed composition at a temperature ranging from about 24℃ to 30℃, for
a duration ranging from about 70 hours to 200 hours to obtain the briquette.
In an embodiment, Figure 7 provides a graphical representation of the process involved in the
preparation of the briquette according to the present disclosure.
30
In an embodiment, Figure 8A of the present disclosure describes pressing of the composition
during preparation of the briquette. Further, Figure 8B provides an illustrative image of the
briquette of the present disclosure and its dimensions.
18
The present disclosure further discloses a process for producing ferroalloy employing the
briquette described above. The present disclosure provides for an improved and economical
process for producing ferroalloy with reduced slag generation.
5 In some embodiments of the present disclosure, the process of producing ferroalloy comprisesproviding the briquette and raw material(s) to a furnace, followed by smelting to obtain the
ferroalloy.
In some embodiments of the present disclosure, in the process of producing ferroalloy, slag
10 yield is reduced by about 30% to 40% when compared to a process devoid of charging the
briquette described above. The inventors of the present disclosure have particularly identified
that the briquette of the present disclosure plays an important role in slag reduction during the
production of ferroalloy, including but not limited to ferrochrome.
15 In some embodiments of the present disclosure, in the process of producing ferroalloy, the raw
material(s) includes but not limited to chromite ore or Manganese ores (Mn/Fe-4), quartzite,
and coke.
In an exemplary embodiment of the present disclosure, the process of producing ferroalloy
20 comprises- charging predetermined amount of the briquette and predetermined amount of raw
material(s) including but not limited to chromite ore or Manganese Ores (Mn/Fe-4), quartzite,
and coke, followed by smelting at a predetermined temperature and predetermined duration to
obtain the ferroalloy, including but not limited to ferrochrome.
25 The inventors of the present disclosure have identified that by employing the briquette
described above in the process of producing ferroalloy including but not limited to
ferrochrome, usage of coke per se is significantly reduced. Thus, making the production of
ferroalloy, including but not limited to ferrochrome significantly economical when compared
to conventional process for producing the ferroalloy.
30
It is to be understood that the foregoing description is illustrative not a limitation. While
considerable emphasis has been placed herein on features of this disclosure, it will be
appreciated that various modifications can be made, and that many changes can be made in the
preferred embodiments without departing from the principles of the disclosure. Those skilled
19
in the art will recognize that the embodiments herein can be practiced with modification within
the spirit and scope of the embodiments as described herein. Similarly, additional embodiments
and features of the present disclosure will be apparent to one of ordinary skill in art based upon
the description provided herein.
5
Descriptions of well-known/conventional methods/steps and techniques are omitted so as to
not unnecessarily obscure the embodiments herein. Further, the disclosure herein provides
examples illustrating the above-described embodiments, and in order to illustrate the
embodiments of the present disclosure, certain aspects have been employed. The examples
10 used herein for such illustration are intended merely to facilitate an understanding of ways in
which the embodiments may be practiced and to further enable those of skill in the art to
practice the embodiments. Accordingly, the following examples should not be construed as
limiting the scope of the embodiments herein.
15 EXAMPLES
Materials
Coke fines amounting to 1t were obtained from the plant located in the eastern part of India.
Dextrin (99%), Humic acid (99%), Sodium silicate (99%), and polyvinyl alcohol (99%) were
20 obtained from Loba Chemie. Starch (99%) was obtained from Fisher Scientific, Bentonite,
Pregel starch, molasses, lime, sodium silicate, Acrobind, Borregard DP, Borregard 3837 and
Molasses were available as commercial grade and obtained from commercial sources.
Millipore double distilled water was used as the solvent for all synthesis purposes.
25 Example 1: Preparation of the composite binder
About 80 kg of ordinary portland cement (OPC 53 grade), about 40 kg of bentonite and about
80 kg pregel starch were mixed in a proportion of 4: 2: 4 and blended at a temperature of about
27°C, for a duration of about 15 minutes to obtain the composite binder. The obtained
composite binder had particle size of about 45 µm.
30
Example 2: Preparation of the composite binder
About 90 kg of ordinary Portland cement (OPC 53 grade), about 30 kg of bentonite and about
90kg of pregel starch were mixed in a proportion of 3:1:3 and blended at a temperature of about
20
27°C, for a duration of about 15 minutes to obtain the composite binder. The obtained
composite binder had particle size of about 45µm.
Example 3: Preparation of the briquette composition
5 About 90% of coke fines were mixed with about 10% of the composite binder prepared in
Example 1 or Example 2 above, alongside water of about 10%, at a temperature of about 27
°C, for a duration of about 3 minutes, to obtain the briquette composition.
Table 1 provides chemical analysis of the coke fines.
10
Table 1:
Figure 1 describes a plot illustrating the size distribution of coke fines.
Figure 2 describes a plot illustrating X-ray diffraction analysis of the coke fines.
Coke Fines
Components Values (%)
Proximate analysis
Ash 14.08
VM 5.95
FC 79.97
Chemical Analysis
Elements/Compounds
S 0.7
Phos 0.014
SiO2 30
Al2O3 23.83
Fe2O3 12.75
MgO 1.75
CaO 1.11
MnO -
Cr2O3 28.1
21
Figure 3A describes scanning electron microscopy (SEM) micrograph of the coke fines; and
Figure 3B describes Energy-dispersive X-ray spectroscopy (EDS) analysis of coke fines
derived from the SEM analysis.
5 Example 4: Preparation of the briquette composition
About 92% of coke fines (described in Example 3) were mixed with about 8% of the composite
binder prepared in Example 1 or Example 2 above, alongside water of about 10% at a
temperature of about 27 °C, for a duration of about 2 or 2.5 min, to obtain the briquette
composition.
10
Example 5: Preparation of the briquette composition
About 93% of coke fines (described in Example 3) were mixed with about 7%of the composite
binder prepared in Example 1 or Example 2 above, alongside water of about 10%, at a
temperature of about 27°C, for a duration of about 2 or 3mins, to obtain the briquette
15 composition.
Example 6: Preparation of the briquette
About 500Kg of the briquette composition prepared in Example 3 or Example 4 or Example 5
was passed through roller press through a hopper. Figure 8A illustrates a pictorial
20 representation of the pressing of briquette composition using the roller press. The pressing was
carried out at a force of about 100kgf tf. The pressed composition was subjected to curing at a
temperature of about 27°C, for a duration of about 2 min, to obtain the briquette.
Figure 7 provides a graphical representation of the preparation of the briquette.
Table 2 describes the chemical analysis and properties of the briquettes (coke briquettes)
25 obtained according to Example 6 in different batches in a conventional briquetting machine.
Elements Coke
Briqu
ette
Batch
11
Coke
Briqu
ette
Batch
10
Coke
Briqu
ette
Batch
9
Coke
Briqu
ette
Batch
7
Coke
Briqu
ette
Batch
6
Coke
Briqu
ette
Batch
4
Coke
Briqu
ette
Batch
3
Coke
Briqu
ette
Batch
2
Coke
Briqu
ette
Batch
1
Co
ke
Fin
es
%Ash 12.25 22.72 20.14
1
14.76 15.18 24.9 22.34 16.94 23.37 14.
08
22
[CB: Composite Binder comprising Portland Cement, Bentonite and Pregel Starch; CF: Coke
Fines; MT: Mixing time; CCS: cold compressive strength; CSR: coke strength after reaction;
CRI: coke reactive index]
Table 2:
5
%VM 10.34 10.01 7.385 11.29 10.83 10.01 12.46 10.5 11.99 5.9
5
%FC 77.41 67.27 72.47
4
73.95 73.99 75.09 74.72 72.56 74.64 79.
97
%S 0.46 0.22 0.411 0.24 0.2 0.256 0.36 0.22 0.36 0.7
%Phos 0.017 0.018 0.016 0.019 0.019 0.019 0.016 0.015 0.016 0.0
14
%SiO2 32.42 25.79 28.81 31.05 32.09 24.2 30.1 29.31 30.05 30
%Al2O3 14.84 14.11 15.19 14.74 15.13 13.7 15.6 14.35 15.61 23.
83
%Fe2O3 12.04 12.76 9.78 11.99 11.75 11.9 12.93 12.65 13.69 12.
75
%MgO 6.69 8.44 4.958 7.10 7.12 7.9 6.93 6.58 7.6 1.7
5
%CaO 8.75 6.84 4.820 8.24 8.4 6.68 10.1 6.433 8.1 1.1
1
%Cr2O3 24.14 31.2 28.81 25.91 25.45 34.7 24.16 30.7 24.9 28.
1
CCS
kgf/briqu
ette
110 99.9 149 144 211 183 145 99.7 109 -
CRI 33 32 37 37 39 38 37 32 33
CSR 19 18 20 20 21 20 20 18 19
porosity 38 39 36 36 33 35 36 39 38
Conditio
n
CB:7
%
MT: 3
min
CF:93
%.
CB:
7%
MT: 2
min
CF:
93%.
CB:
8%
MT: 2
min
CF:
92%.
CB:
8%
MT: 2
min
CF:
92%.
CB:
10%
MT: 3
min
CF:
90%.
CB:
8%
MT:
2.5
min
CF:
92%.
CB:
7%
MT: 2
min
CF:
93%.
CB:
7%
MT: 2
min
CF:
93%.
CB:
7%
MT: 2
min
CF:
93%.
23
Figure 9 describes cold compressive strength (CCS) of the briquettes (coke briquettes).
According to the data in Figure 9, the briquettes had CCS ranging from about 99 kgf/briquette
to 211 kgf/briquette.
5
Figure 10 provides a plot describing the resistivity of the briquettes of the present disclosure in
comparison with coke fines (C), a combination of coke fines and pregel starch (C+PS),
combination of cokes fines and bentonite (C+Be), and combination of coke fines, bentonite
and cement (C+Be+Ce). The data in Figure 10 demonstrates that the briquette of the present
10 disclosure (C+PS+Be+Ce) has improved resistivity when compared to coke fines, C+PS, C+Be
and C+Be+Ce, respectively. According to the data in figure 10, the briquette of the present
disclosure has resistivity ranging from about 10 m𝞨.m to 15 m𝞨.m.
Figure 11 provides a plot describing the contact angle of the briquette of the present disclosure
15 (coke briquette) and coke fines. According to the data in Figure 11 contact angle of the briquette
is 44 °, which is significantly lesser when compared to the contact angle of the coke fines (80°).
Reduced contact angle of the briquette of the present disclosure signifies better binding power.
Figure 12 provides a plot describing thermogravimetric analysis (TGA) data of the briquette
20 (coke briquette) of the present disclosure, pregel starch and a combination of cement and
bentonite. The briquette of the present disclosure, pregel starch and combination of cement and
bentonite were heated respectively to a high temperature of about 1100 °C to analyze their
thermal degradation behaviour. The data in Figure 12 demonstrates that the briquette of the
present disclosure is thermally stable and does not undergo degradation, i.e., weight loss even
25 at a temperature of about 1100 °C.
Figure 13 provides scanning electron microscopy (SEM) micrographs of briquette of the
present disclosure and coke fines, representing the micrograph texture showing intramolecular
bonding after binder addition.
30
Figure 16 provides a plot illustrating cold compressive strength (CCS) and weight loss of the
briquette of the present disclosure at varied temperature values, demonstrating the thermal
behaviour of the briquette, post-heat treatment.
24
Figure 17 provides a plot describing hot stage microscopy analysis of ULP coke (commercially
available product) and briquette of the present disclosure. The analysis shows that the coke
briquette has similar thermal stability as that of the ULP coke at room temperature (23°C) and
high temperature (1145°C).
5
Figure 18 provides a plot describing thermogravimetric analysis (TGA) data of the briquette of
the present disclosure (coke briquette) and ULP coke (commercially available product). The
data in the figure shows that the coke briquette is thermally stable and does not undergo weight
loss, i.e., degradation until 1000 °C, which is similar to ULP coke.
10
The obtained briquettes were subjected to SEM analysis and XPS analysis.
SEM analysis:
Figure 13B shows presence of composite binder between the two coke particles. It is noted that
the composite binders bond the two-particle by the process of physisorption. As noted in Figure
15 13B, the microstructure appears to be the fusion of coke particles under composite binder
swelled gel matrix, which creates efficient bonding between the interparticles responsible for
the excellent strength of a briquette. The role of the composite binder helps in an association
of coke particles which is confirmed by the micrograph. EDS spectra with elemental mapping
is shown in Figure 14 which marks the presence of necessary elements embedded through
20 composite binder incorporation. Ca, Al, Fe and Si from the composite binder form in situ
phases which eventually join two carbon molecules by Vander Walls force.
XPS analysis:
25 The elements C, N, O, Fe, S, Al, Mg, Ca, Si, Na, and Cr in briquettes of the present disclosure were
studied using XPS, as shown in Figure 15(A-J). The binding state of C 1s is deconvoluted into two
peaks; the peak at 284.84 eV represents the Fe3C phase in the compound. The C-O-C bond that joins
the starch molecule’s two aromatic rings reaches its maximum energy at 287.5 eV. The shift in binding
energy corresponds to the emergence of various phases connected within the binder. The peak at 350.6
30 eV is related to the inherent formation of CaSO4 in the briquette, Conversely, the peak at 347.2 eV
relates to the calcite phase found in the briquette, primarily associated with cement. Deconvolution of
Fe2p spectra is represented by two peaks, one at 711.9 eV, representing Fe3C phase purity in the
briquette, and the other at 724.6 eV, indicating Fe+2 surface oxidation states. The XPS spectra of Al 2p
are deconvoluted into one peak at (74.7 eV), which corresponds to Al(OH)3 generated during the
35 hydration reaction of cement during the curing period, and Si 2p (102.9 eV), which corresponds to
25
Si3N4 in the briquette. The N 1s spectra are deconvoluted into a single peak, 400.63 eV, which reveals
the presence of a (C=O)-N bond in the starch polymer. Na 1s spectra correspond to a peak at 1071.07
eV, indicating that sodium relates to aluminosilicate, which indicates the presence of bentonite in the
briquette. The presence of phase development of FeCO3 after briquetting is shown by deconvoluting
5 the O 1s spectra into two conspicuous peaks, one of which is at 532.02 eV. Organic C=O of the
pregelatinized starch polymer is the other peak, which is located at 534.37 eV. In the case of Cr 2p, the
spectra deconvoluted into two peaks; the binding energy at 577.2 eV is basically Cr 2p3/2 representing
Cr(OH)3 while the other peak of Cr 2p1/2 belongs to NaCrO2. The XPS investigation analysis depicts
the formation of new phases responsible for strength and well-integrated composite binder with coke
10 fines.
Example 7: Comparative Example 1
The briquette obtained in Example 6 above was subjected to smelting analysis for production of
ferroalloy, such as ferrochrome. The obtained briquette was used to replace part of the ULP coke
15 (commercially available) used for production of ferrochrome.
Table 3 describes smelting conditions.
Test1: Cr Ore:1 kg, ULP Coke: 300 g, Quartz: 110
g Holding time: 12 min
Test 2: Cr Ore:1 kg, ULP coke: 240 g, Coke
briquette (of the present disclosure): 60 g,
Quartz:110 g and Holding time:12 min
Table 3:
20 Table 4 describes output of the smelting process. The data in Table 4 demonstrates that use of the
briquette of the present disclosure (coke briquette) by partially replacing the ULP coke (commercially
available) significantly reduces the slag formation.
SL. No. Test Alloy yield (g) Slag yield (g)
1 ULP Coke - Test 1 397 517
2. 80 % ULP coke +20
% briquette of the
present disclosureTest 2
388 363
Table 4:
25
26
Further, Table 5 demonstrates cost benefit in the smelting process during the production ferroalloy, such
as ferrochrome by replacing ULP coke with briquette of the present disclosure.
Price of Coke fines (US
$/MT)
376.911
66
Coke fines briquetting business case calculation
FC of coke fines (%) 77
Price of lumpy coke
(US $/ MT)
530.861
37
Particulars Sp.
Consumptio
n
US $/MT US $/ MT coke
fines
FC of lumpy coke
(%)
84 Coke fines 1 376.9116 376.9116
Pregel starch 0.028 780 21.84
OPC-cement 0.028 78 2.184
Bentonite 0.014 130 1.82
Briquetting
Fixed cost
- 10.4 10.4
Cost of coke
briquette
(Rs/MT
briquette)
- 386.126729
Cost of
carbon unit
of coke
briquette
(Rs./kg
carbon)
- 0.536565714
Cost of
carbon unit
of lump coke
(Rs./kg
carbon)
- 1
Benefit per
carbon unit
replacement
(Rs./kg
carbon)
0.095
27
Benefit per
ton of carbon
unit
replacement
(Rs./MT
carbon)
95
Amount
carbon unit
required for
50KTA @
0.45 specific
carbon
22500.00
Benefit for
10%
replacement
with
briquette of
the present
disclosure
US $.
(Millions)
0.215
Benefit for
20%
replacement
with
briquette of
the present
disclosure
US $.
(Millions)
0.429
Benefit for
100%
replacement
with
briquette of
the present
disclosure
US $.
(Millions)
2.147
Table 5:
Data in Table 5 demonstrates that:
28
• replacing 10% of ULP with briquette during the production of ferrochrome leads to about USD
0.215 million cost benefit;
• replacing 20% of ULP with briquette during the production of ferrochrome leads to about USD
0.429 million cost benefit; and
5 • replacing 100 % of ULP with briquette during the production of ferrochrome leads to about
USD 2.147 million cost benefit.
This data from Table 5 explicitly demonstrates that use of coke briquette for the production of ferroalloy,
such as ferrochrome is significantly economical when compared to use of commercially available ULP
coke.
10
Example 8: Comparative Example 2
Assessment of coke briquette prepared using the briquette composition according to the present
disclosure alongside coke briquettes prepared using coke fines and other composite binder compositions
15 (comparative composition) was carried out. All the briquettes were prepared by employing automatic
hydraulic pressing. Results from the assessment is provided in Table 6.
Sample Raw Material Binder CCS
(kgf/briquette)
No. of
Drops
Comparative
Composition-1
Coke fines (93.8%) CMC (0.2%)+ Cement(4%) +
Bentonite(2%)
380 35
Comparative
Composition-2
Coke fines (93.7%) CMC (0.3%)+ Cement(4%) +
Bentonite(2%)
442 42
Comparative
Composition-3
Coke fines (93.6%) CMC (0.4%)+ Cement(4%) +
Bentonite(2%)
350 26
Comparative
Composition-4
Coke fines (93%) Molasses (1%)+
Cement(4%)+ Bentonite(2%)
79 7
Comparative
Composition-5
Coke fines (96%) Borregard(2%) +
Bentonite(2%)
154 12
Comparative
Composition-6
Coke fines (96%) Borregard 3837 (2%) +
Bentonite (2%)
150 17
Comparative
Composition-7
Coke fines (94%) Cement (4%) + Bentonite
(2%)
90 14
29
[CMC: carboxy methyl cellulose]
Table 6:
Data from Table 6 clearly demonstrates that the briquettes obtained according to the composition of
5 present disclosure exhibits higher cold compressive strength (CCS) of about 650 kgf/briquette and
remains intact and stable upon drops upto about 80 when compared to briquettes formed using
comparative compositions.
Additional embodiments and features of the present disclosure will be apparent to one of ordinary skill
10 in art based on the description provided herein. The embodiments herein provide various features and
advantageous details thereof in the description. Descriptions of well-known/conventional methods and
techniques are omitted so as to not unnecessarily obscure the embodiments herein.
The foregoing description of the specific embodiments reveal the general nature of the embodiments
15 herein that others can, by applying current knowledge, readily modify and/or adapt for various
applications such specific embodiments without departing from the generic concept, and, therefore,
such adaptations and modifications should and are intended to be comprehended within the meaning
and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or
terminology employed herein is for the purpose of description and not of limitation. Therefore, while
20 the embodiments in this disclosure have been described in terms of preferred embodiments, those
skilled in the art will recognize that the embodiments herein can be practiced with modification within
the spirit and scope of the embodiments as described herein.
Throughout this specification, the term ‘combinations thereof’ or ‘any combination thereof’ or ‘any
25 combinations thereof’ are used interchangeably and are intended to have the same meaning, as regularly
known in the field of patents disclosures.
Comparative
Composition-8
Coke fines (92%) Cement (6 %) + Bentonite
(2%)
89 7
Comparative
Composition-9
Coke fines (93.5%) Acrobind (0.5 %) + Cement
(4%) + Bentonite (2%)
131 9
Comparative
Composition-10
Coke fines (93%) Acrobind (1 %) + Cement
(4%) + Bentonite(2%)
156 8
Composition of
the present
disclosure
Coke fines (90%) Pregel Starch (4%) +
Bentonite (2%) + Cement
(4%)
650 80
30
As regards the embodiments characterized in this specification, it is intended that each embodiment be
read independently as well as in combination with another embodiment. For example, in case of an
embodiment 1 reciting 3 alternatives A, B and C, an embodiment 2 reciting 3 alternatives D, E and F
and an embodiment 3 reciting 3 alternatives G, H and I, it is to be understood that the specification
5 unambiguously discloses embodiments corresponding to combinations A, D, G; A, D, H; A, D, I; A, E,
G; A, E, H; A, E, I; A, F, G; A, F, H; A, F, I; B, D, G; B, D, H; B, D, I; B, E, G; B, E, H; B, E, I; B, F,
G; B, F, H; B, F, I; C, D, G; C, D, H; C, D, I; C, E, G; C, E, H; C, E, I; C, F, G; C, F, H; C, F, I, unless
specifically mentioned otherwise.
10 While considerable emphasis has been placed herein on the particular features of this disclosure, it will
be appreciated that various modifications can be made, and that many changes can be made in the
preferred embodiments without departing from the principles of the disclosure. These and other
modifications in the nature of the disclosure or the preferred embodiments will be apparent to those
skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing
15 descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.
31
WE CLAIM:
1. A briquette composition comprising:
coke fines; and
composite binder comprising ordinary portland cement, bentonite, and pregel
5 starch.
2. The briquette composition as claimed in claim 1, wherein the coke fines are present
in an amount ranging from about 90 wt.% to 95 wt.%.
3. The briquette composition as claimed in claim 1, wherein the composite binder is
present in an amount ranging from about 1 wt% to 10 wt%.
10 4. The briquette composition as claimed in claim 1, wherein the composite binder
comprises ordinary portland cement in an amount ranging from 2% to 6%;
bentonite in an amount ranging from about 1 % to 4%, and pregel starch in an
amount ranging from about 2% to 6%.
5. The briquette composition as claimed in claim 1, wherein the composite binder
15 comprises ordinary portland cement, bentonite, and pregel starch in a ratio ranging
from 2:1:2 to 3:2:3; preferably in a ratio of 4:2:4.
6. The briquette composition as claimed in claim 1, wherein the coke fines have
particle sizes ranging from about 1000 µm to 5000 µm.
7. The briquette composition as claimed in claim 1, wherein the composite binder has
20 particle size ranging from about 30 µm to 45 µm.
8. The briquette composition as claimed in claim 1, wherein the coke fines comprises
about 0.5% to 1.5 % of CaO, about 25% to 35 % of SiO2, about 0.5% to 0.8 % of
S, about 9% to 13 % of Fe(T), about 25% to35% of Cr2O3, about 0.011% to 0.016
% of P, about 1% to 3 % of MgO, about 0.4% to 0.6% of MnO, about 20% to 30%
25 of Al2O3, about 0.1% to 0.4% of TiO2, about 78% to 82% of fixed carbon, about
5.8% to 6.2% of volatile material and 13% to 15% of ash content.
9. The briquette composition as claimed in claim 1, wherein the composition
optionally comprises moisture content ranging from about 8 to 10 %.
10. A process for preparing the briquette composition as claimed in claim 1, said
30 process comprising mixing of the coke fines, and the composite binder, optionally
along with water to obtain the briquette composition.
11. The process as claimed in claim 10, wherein the mixing is carried out at a
temperature ranging from about 24℃ to 27℃, for a duration ranging from about
0.5 minutes to 3 minutes.
32
12. A briquette obtained by the composition as claimed in claim 1.
13. The briquette as claimed in claim 12, wherein the briquette has moisture content
ranging from about 2% to 6%.
14. The briquette as claimed in claim 12, wherein the briquette has electrical resistivity
5 ranging from about 10 m𝞨.m to 15 m𝞨.m.
15. The briquette as claimed in claim 12, wherein the briquette comprises ash content
of about 12% to 25 %, volatile material of about 7% to 13 %, fixed carbon of about
67% to 78%, Sulphur of about 0.1% to 0.5 %, Phosphorous of about 0.014% to
0.019%, SiO2 of about 24% to 33%, Al2O3 of about 12% to 16 %, Fe2O3 of about
10 9 % to 14 %, CaO of about 4% to 10 %, and Cr2O3 of about 24% to 35%.
16. The briquette as claimed in claim 12, wherein the briquette is thermally stable up
to a temperature of about 1300-1400 °C.
17. The briquette as claimed in claim 12, wherein the briquette has coke reactive index
(CRI) ranging from about 32% to 45%; has coke strength after reaction (CSR)
15 ranging from about 18% to 25%; has porosity ranging from about 32% to 39%; has
cold compressive strength (CCS) ranging from about 98 kgf/briquette to 700
kgf/briquette; has bulk density(B.D.) ranging from about 1.1 gm/cc to 1.4 gm/cc;
has true density (T.D.) ranging from about 1.5 gm/cc to 2.0 gm/cc and has contact
angle ranging from about 42˚ to 46˚.
20 18. The briquette as claimed in claim 12, wherein the briquette is intact and stable upon
drops ranging from about 60-120, according to drop test.
19. A process for producing the briquette as claimed in claim 12, said process
comprising:
• blending of coke fines, composite binder and solvent to obtain the composition,
25 followed by molding;
• pressing the molded composition; and
• curing the pressed composition to obtain the briquette.
20. The process as claimed in claim 19, wherein the blending is carried out at a
temperature ranging from about 24℃ to 27℃, for a duration ranging from about 1
30 to 3 minutes.
21. The process as claimed in claim 19, wherein the solvent is water, in an amount
ranging from about 8 to 10 %.
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22. The process as claimed in claim 19, wherein the pressing is carried out for a
duration ranging from about 0.5 minutes to 2 minutes, at a compressive force
ranging from about 5 tf- 50 tf.
23. The process as claimed in claim 19, wherein the pressing is carried out by technique
5 selected from a group comprising roller pressing, hydraulic pressing, extrusion
machine, and a combination thereof.
24. The process as claimed in claim 19, wherein the curing is carried out at a
temperature ranging from about 24℃ to 30℃, for a duration ranging from about
70 hours to 200 hours.
10 25. A process for producing ferroalloy, said process comprising providing the briquette
as claimed in claim 12 and raw material(s) to a furnace, followed by smelting to
obtain the ferroalloy.
26. The process as claimed in claim 25, wherein slag yield is reduced by about 30% to
40% when compared to a process devoid of charging the briquette.
15 27. The process as claimed in claim 25, wherein the raw material(s) comprise chromite
ore or Manganese Ores (Mn/Fe-4), quartzite, and coke.