Title of Invention

ORGANO-REFINING PROCESS TO PRODUCE LOW ASH (<4%) CLEAN COAL WITH MAXIMUM POSSIBLE YIELD

Abstract The present invention comprises a process of organo-refining of coal to produce low ash (<4%) clean coal with higher yields of 65%-70%. Dried coal sample was extracted under reflux conditions with a solvent containing N-methyl 2- pyrrolidone (NMP) and ethylenediamine in a ratio of coal NMP:EDA of 1:17:1. The process of organo-refining of coal to obtain clean coal with low ash (<4%) within permissible limit for coke making in high enough yield for coke making has been described.
Full Text 2
FIELD OF THE INVENTION
The present invention generally relates to a process of coal cleaning. More
particularly, the present invention relates to a process of organo-refining to
produce low ash ( BACKGROUND OF THE INVENTION
A prior art discloses, organo-refming or solvent extraction technology is
beneficial to produce super clean coal or ultra clean coal where the ash
content of clean coal is as low as (0.5%) but the problem was noticed that
the yield of clean coal is low about 40% which is not economically viable for
coke making. There are potential use of this ultra clean coal both as a fuel
and non fuel.
The present invention emphasizes an organo-refining process to produce low
ash coal within permissible limit (upto extraction of high yield to make economically feasible for coke making.

2(A)
A US Patent No. 3988238 discloses an invention for "Process for recovering
upgraded product from coal" the abstract of which recites a process for
recovering and upgrading products from solid coal by contracting the coal
with a dense-water containing fluid at a temperature in the range of from
about 600°F to about 900°F in the absence of externally supplied hydrogen or
other reducing gas and in the presence of a sulphur resistant catalyst.
i.e. Extraction of sulphur from coal by use of super critical fluids-use of water-
methanol-CO2 under to super critical conditions.
Another US Patent No. 4338183 discloses an invention of method of solvent
extraction of coal by heavy oil describes the conversion of coal to liquid
product. The abstract of which recites a solid carbonaceous material such as
coal is converted to liquid products and the asphaltene content of a heavy
hydrocarbonaceous liquid is reduced in the process wherein the solid is
solvent extracted by the heavy hydrocarbonaceous liquid is reduced in the
process wherein the solid is solvent extracted by the heavy
hydrocarbonaceous liquid and a hydrocarbonaceous recycle stream with a
finely divided, unsupported metal catalyst and the resultant mixture of liquid
is recovered as the product.
A further US Patent No. 5955375 discloses an invention entitled " Production
of coal derivation products utilizing NMP Type Solvent extraction "
The abstract of which recites a graphite of anisotrophy selected between
substantially isotropic to highly anisotrophic, or calcined coke graphitizable to

2(B)
such a graphite, or a pitch convertible into such a coke or graphite, is derived
from bituminous coal. A first coal is extracted in NMP or like solvent to give a
first extract that when carbonised alone produces a substantially isotropic
coke. A second coal (the same or different as the first coal) is hydrogenated
and similarly extracted to give a second extract. The extent of hydrogenation
is controlled so that the second extract when carbonised alone produces a
highly anisotropic coke. Test samples are prepared by combining the two
extracts in different ratios including one sample in a ratio at each range end
of the range. The solids of each sample are recovered, carbonised into coke,
and then optionally converted into graphite, and its degree of anisotrophy
analyzed. Comparison of the analyzed degrees for the different coke or
graphite samples gives an correlation (e.g. a curve), that is characteristic for
the coal treated. From this correlation, the two fractions can be solution
blended in correct proportion to give a pitch yielding a coke or graphite of a
selected anisotrophy or the coke or graphite can be produced therefrom.
Alternatives are disclosed for combining the coals as such for extraction or
variably hydrogenating a single coal to correspond in either case to a selected
degree of anisotrophy.
That means solvent extraction followed by hydrogeneration to produce
anisotrophic coke and graphite.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose a process of
organo-refining to produce low ash ( which eliminates the disadvantages of prior art.

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In the process of organo-refining of coal In NMP and EDA, a small coal
sample of 10gm from previous sample was isolated and kept in a 250 ML
round bottom flask fitted with a reflux condenser and containing NMP of
170-180 with a small amount of 10-20mL which creates a ratio of coal
sample: NMP:EDA is 1:17:1. The coal and solvent mixture was refluxed for
2-3 hours then the mixture was filtered through 500 mesh stainless steel
cloth. The residual coal (RC) was washed with 2% aquash Hydro chloric
Acid to remove EDA. Thereafter final washing was done with distilled
water. The RC obtained after washing was dried over night in the oven
and weighed to get the weight percentage of residual coal.
The liquid extracts (filtrates) collected after filtration, were concentrated
upto-85% by distillation. Concentrated solution is poured in distilled water.
Thus, the clean coal was precipitated in distilled water which acts as an anti
solvent. The precipitated clean coal was then filtered using filter paper and
washed several times until the filtrate becomes colouress. The clean coal
was dried overnight in an oven at 105°C and weighted to get the yield
(wt%) of clean coal. The clean coal and residual coal obtained from above
process was analyzed for its ash content.
Thereafter for further development, the size analysis of feed and the two
products was carried out. It was noticed that the process undergo changes
the size distribution of coal. The coal sample was refluxed for 2 hours,

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then the refluxed mix was filtered in 500 stainless steel mesh cloth and
result obtained in the increase in yield of clean coal and simultaneously
increase in as content of clean coal ( The mass balance of ash content are as follows:-
(28.6)*(1.0)+(65.0-28.6)*(X)=(65.0)*(3.8) where X is the ash content of
extra yield obtained because of coarse filtration. In table 2, it show that
ash content of -500 mesh fraction of feed sample is 14.05/. So it is very
clear that this Improvement in result is not simply because of coarse cut,
rather it is because of partial dissolution phenomena during the process.
This invention is capable to produce low ash ( making purpose with very high yield.
The test conducted with NMP and EDA as solvent and the result are as
follows.
Table 1: Test results with fine filtration and coarse filtration


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Table 2: Size wise ash analysis of feed coal sample


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WE CLAIM
1. A process of organo-refining to produce low ash ( with maximum yield comprising following steps.
collecting a sample of 10gms of clean coal;
- making mixture with NMP and EDA and sample;
- refluxing the mixture for 2 hours;
- filtering the mixture through 500 mesh stainless steel cloth;
- washing the residual coal with 2% aquash Hydrochloric acid to
remove EDA;
- final washing by distilled water;
- drying the residual coal over night in the oven;
- taking weight of residual coal and;
recovering upto 85% of the solvent by distilling off the filtrate

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- pouring the coal-solvent concentrate in water
- precipitating the clean coal in water
filtering the coal to separate coal and solvent water solution
- washing the clean coal with water
- drying the clean coal overnight in oven
taking the weight of clean coal
calculating weight percentage of coal and yield;
characterized in that the mixture of the sample, NMP and EDA is
arrange at a ratio of 1:17:1.

The present invention comprises a process of organo-refining of coal to produce low ash ( ash (

Documents:

01292-kol-2006 dt.21.02.2007-correspondence-1.2.pdf

01292-kol-2006 dt.21.02.2007-form 9.pdf

01292-kol-2006 dt.24.04.2008-petition under rule 137.pdf

01292-KOL-2006 Dt.24.04.2008-REPLY F.E.R.pdf

01292-kol-2006-abstract.pdf

01292-kol-2006-asignment.pdf

01292-kol-2006-claims.pdf

01292-kol-2006-correspondence other.pdf

01292-kol-2006-correspondence-1.1.pdf

01292-kol-2006-description (complete).pdf

01292-kol-2006-form-1.pdf

01292-kol-2006-form-2.pdf

01292-kol-2006-form-3.pdf

01292-kol-2006-form-9.pdf

1292-KOL-2006-ABSTRACT 1.1.pdf

1292-KOL-2006-CLAIMS 1.1.pdf

1292-KOL-2006-DESCRIPTION (COMPLETE) 1.1.pdf

1292-kol-2006-form 15.pdf

1292-KOL-2006-FORM 2.1.pdf

1292-kol-2006-granted-abstract.pdf

1292-kol-2006-granted-claims.pdf

1292-kol-2006-granted-correspondence.pdf

1292-kol-2006-granted-description (complete).pdf

1292-kol-2006-granted-examination report.pdf

1292-kol-2006-granted-form 1.pdf

1292-kol-2006-granted-form 18.pdf

1292-kol-2006-granted-form 2.pdf

1292-kol-2006-granted-form 3.pdf

1292-kol-2006-granted-gpa.pdf

1292-kol-2006-granted-reply to examination report.pdf

1292-kol-2006-granted-specification.pdf


Patent Number 229474
Indian Patent Application Number 1292/KOL/2006
PG Journal Number 08/2009
Publication Date 20-Feb-2009
Grant Date 18-Feb-2009
Date of Filing 28-Nov-2006
Name of Patentee TATA STEEL LIMITED
Applicant Address JAMSHEDPUR
Inventors:
# Inventor's Name Inventor's Address
1 MITALI CHINA R&D IIT, DELHI, TATA STEEL LIMITED, JAMSHEDPUR 831001
2 D.K. SHARMA R&D IIT, DELHI, TATA STEEL LIMITED, JAMSHEDPUR 831001
PCT International Classification Number B 01 D
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA