Title of Invention

COST-EFFECTIVE PROCESS FOR FORMING COKE BRIQUETTES.

Abstract An improvement in the process for forming coke briquettes using new binder system. The present invention makes use of waste lime stone fines as a binder. The coke briquettes formed using new binder system gives a substitute for starch bound coke briquettes.
Full Text FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention. - COST-EFFECTIVE PROCESS FOR FORMING COKE BRIQUETTES.


2. Applicant(s)




(a) NAME : GHCL LIMITED
(b) NATIONALITY: INDIAN
(c) ADDRESS : Sutrapada, District Junagadh, Gujarat 362275, State of Gujarat, India.

3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:


Field of Invention:
The present invention relates to an improvement in the process for forming coke briquettes disclosed and claimed in main patent application no. 435/MUM/2004.
More particularly the improvement relates to the selection of binder in the process whereby the product is produced much more economically without compromising on the quality of the product.
Background of the Invention:
A cost effective process of manufacturing lime that addresses the selection of proper fuel for the conversion of limestone into lime in vertical shaft limekilns is already disclosed in Parent Application No-435/MUM/2004.
435/MUM/2004 uses starch as a binder for forming coke briquettes. Despite of advantages of using starch as a binder, the overall cost of production of lime from limestone can be further reduced by using combination of starch and lime stone fines/ chalk powder as a binder.
The process of the said main application no 435/MUM/2004 comprises the following steps:
uniformly mixing and kneading coke breeze with starch and liquid
preferably water,
compacting the mass in a twin roll press to obtain green briquettes,

curing the green briquettes in curing chamber using flue gas having inlet temperature 200 - 300 deg. C. for three hours or optionally drying in sunlight for 3-4 days.
It is surprisingly found by the present inventors that limestone fines (below 1 mm), can be used as one of the components of the binder for coke breeze. Also, chalk powder is available at cost 25 times less as compared to starch.
Thus the present invention is an improvement over the process for forming coke briquettes as disclosed in 435/MUM/2004.
Object of the Invention:
It is thus the object of the present invention to provide an improvement in the process for forming coke briquettes disclosed in our main patent application no 435/ MUM/2004 such that the coke briquettes are obtained more economically.
It is further object of the invention to provide a process for forming coke briquettes in which the binder starch is substituted with new binder system.

Summary of Invention:
An improvement in and relating to a process for forming coke briquettes claimed
in patent application no 435/MUM/2004, the improvement comprising using a
binder system being a mixture of starch and lime stone/chalk powder being
blended in the ratio of 1:1 to 1:2.
Thus according to the invention there is provided a process comprising the steps
of
uniformly mixing and kneading coke breeze with mixture of starch and limestone/ chalk powder with liquid preferably water, compacting the mass in a twin roll press to obtain green briquettes, curing the green briquettes in curing chamber using flue gas having inlet temperature 200 - 300 deg. C. for three hours or optionally drying in sunlight for 3-4 days.
Detailed Description:
A process for forming coke briquettes using starch as a binder, which are used as a fuel in a process for manufacturing lime from limestone in vertical shaft limekilns, is already claimed in main patent application no-435/MUM/2004. The Inventors of the main patent application no-435/MUM/2004 have surprisingly found that the total production cost of manufacturing lime from limestone can be further reduced with the use of combination of starch and limestone as a binder for forming coke briquettes.

The present inventors have found that limestone fines (/minus 1 mm) when used
in combination with starch produces similar results as produced using starch
alone.
It is an added advantage to the soda ash industry that lime stone fines which are
waste, can be used as one of the components of the binder for forming coke
briquettes. Limestone fines are collected from easily available limestone handling
area and dust collectors.
Also chalk powder when used in combination with starch produces similar results
as produced by using starch alone. Chalk powder is available at cost 25 times
less as compared to starch.
In the present invention lime stone fines can be used in the rage of 2- 5% & chalk
powder can be used in the range of 2- 5 %.
Coke briquetting process using combination of starch and limestone/ chalk
powder as a binder used by the present inventors can be summarized as below.
Coke breeze stored in Briquetting plant area is loaded to feed hopper through loader.
Coke breeze from the bottom of feed hopper are then sent to tromwel, with screen (3mm), through conveyor belt and screened. Coke breeze (-3mm) is sent to mixer through conveyor. Speed of the conveyor is so adjusted that desired quantity of coke breeze is reaching at the mixer. Premixed binder mixture (4% limestone fines (-1 mm)/4% chalk powder (-1 mm) and 4% pregelatinised starch) is fed to the mixer through speed controlled rotary valve/screw conveyor. Hot water/steam is fed in desired quantity and is mixed with coke breeze and binder

mixture. Final mixture of the coke breeze, binder components and hot water/steam is dropped through a conical vessel to twin-roll Briquetting machine where the desired green briquettes are produced by compaction. Green briquettes are collected and transported to the sun drying/furnace drying for complete curing.
The details of the invention, its objects and advantages are explained hereunder in greater detail in relation to the non-limiting exemplary illustrations.
EXAMPLES
Comparative analysis of different binders used for coke briquetting process:
A study was carried out to determine effects of different binders on the properties
of coke briquettes after briquetting process.
The binders tried out for this process were starch and combination of starch and
lime stone / chalk powder.
The data so obtained which involved a study of various parameters like moisture,
volatile matter, fixed carbon and gross calorific value of initial coke fines used v/s
the final coke briquettes is as represented in Table 1.
Table 1: Comparative analysis of different binders used for coke briquetting process

Parameters Analysed Initial Coke fines With 7%
starch as
binder Combination I
(Limestone fines4 % + starch 4 %) Combination II
(Chalk powder 4 % + starch 4 %)
Moisture % 4.54 2.4 2.10 2.3
Ash % 25.30 25.80 27.42 27.23

Volatile Matter % 15.01 17.90 18.30 18.41
Fixed Carbon % 55.15 53.85 52.18 52.06
GCV Kcal/kg % 4660 4700 4558 4510
Micum Index M10 - 28.0 29.0 30.0
The aforesaid results clearly go to demonstrate the closely similar properties of the binder system compared to the starch binder used in the main patent application no 435/MUM/2004.
Performance of lime kilns with 100% briquettes having 7% starch as a binder
Test C02 Gas Purity % Lime Activity %
A 40.30 59.94
Performance of lime kilns with 100% briquettes having 4% starch + 4% limestone fines as the binder
Test C02 Gas Purity % Lime Activity %
A 40.1 59.90
Performance of lime kilns with 100% briquettes having 4% starch + 4% chalk powder as the binder
Test C02 Gas Purity % Lime Activity %
A 39.86 58.82

WE CLAIM:
1. A process for the manufacture of lime from limestone in vertical shaft limekilns comprising
providing starch and limestone/chalkpowder bound coke briquettes as source of fuel alone wherein the starch concentration is 3-12% or optionally in combination with metallurgical coke, said briquettes formed by
uniformly mixing and kneading pre-sized coke breeze with starch and lime stone / chalk powder being blended in the ratio of 1:1 to 1:2 and liquid preferably water, compacting the mass in a twin roll press to obtain green briquettes, curing the green briquettes in curing chamber or optionally drying in sunlight and forming lime."
2. The process as claimed in claim 1, wherein the limestone has a concentration of 2 to 5 %.
3. The process as claimed in claim 1, wherein the chalk powder has a concentration of 2 to 5 %.
4. The improved process for forming coke briquettes substantially as hereinbefore described with reference to the preferred aspects, embodiments and features of the invention and illustrated with reference to the examples.
Dated this 24th day of March 2005.
Dr. Sanchita Ganguli OF S. MAJUMDAR & CO. Applicants' Agent
8


Documents:

337-MUM-2005-ABSTRACT(21-8-2008).pdf

337-mum-2005-abstract(24-03-2005).doc

337-mum-2005-abstract.doc

337-mum-2005-abstract.pdf

337-MUM-2005-CLAIMS(21-8-2008).pdf

337-mum-2005-claims(granted)-(24-03-2005).doc

337-mum-2005-claims.doc

337-mum-2005-claims.pdf

337-mum-2005-correspondance-received-ver-170605.pdf

337-mum-2005-correspondance-received.pdf

337-MUM-2005-CORRESPONDENCE(20-10-2008).pdf

337-MUM-2005-CORRESPONDENCE(21-8-2008).pdf

337-mum-2005-description (complete).pdf

337-MUM-2005-DESCRIPTION(COMPLETE)-(21-8-2008).pdf

337-MUM-2005-FORM 1(21-8-2008).pdf

337-mum-2005-form 2(21-8-2008).pdf

337-mum-2005-form 2(24-03-2005).pdf

337-mum-2005-form 2(granted)-(24-03-2005).doc

337-MUM-2005-FORM 2(TITLE PAGE)-(21-8-2008).pdf

337-MUM-2005-FORM 3(21-8-2008).pdf

337-mum-2005-form-1.pdf

337-mum-2005-form-2.doc

337-mum-2005-form-2.pdf

337-mum-2005-form-3.pdf


Patent Number 224364
Indian Patent Application Number 337/MUM/2005
PG Journal Number 02/2009
Publication Date 09-Jan-2009
Grant Date 13-Oct-2008
Date of Filing 24-Mar-2005
Name of Patentee GHCL LIMITED
Applicant Address SUTRAPADA,DISTRICT JUNAGADH, GUJARAT 362275, STATE OF GUJARAT, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 MALHOTRA TEJ GHCL LIMITED, SUTRAPADA, DISTRICT JANAGADH, GUJARAT 362275, STATE OF GUJARAT, INDIA
2 PANDEY RADHEY SHYAM GHCL LIMITED, Sutrapada, District Junagadh, Gujarat 362275, State of Gujarat, India.
3 PAREKH KUMAR KRISHNAKANT GHCL LIMITED, Sutrapada, District Junagadh, Gujarat 362275, State of Gujarat, India.
4 DESHPANDE SURESH NARAYAN GHCL LIMITED, Sutrapada, District Junagadh, Gujarat 362275, State of Gujarat, India.
5 SINGH CHANDRABHAN GHCL LIMITED Sutrapada, District Junagadh, Gujarat 362275, State of Gujarat, India.
PCT International Classification Number C10L5
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA