FIELD OF INVENTION
The present invention relates to development of a process for making
ammonium bicarbonate using the waste generated at integrated steel plant.
BACKGROUND OF THE INVENTION
Generally, the inputs require to operate blast furnaces are lime, coke and iron
ore. Each of these inputs are produced indenegeously in the integrated steel
plant so that the size and quality are properly maintained. Coke is produced by
carbonization of coke in coke oven batteries. The products from the coke oven
plant are coke and coke oven gas. Ammonia, one of the constituents of coke
oven gas is removed by quenching, cooling and condensation. Thus concentrated
ammoniacal liquor (CAL) is produced. This CAL contains 14-16% ammonia. To
take care of environmental concerns it possess ammonia is incinerated in some
of the plants.
Lime is another input material for steel melting shops in an integrated steel
plant. Lime is produced by calcinations of lime stone. In the process of
calcinations, calcium carbonate dissociates into calcium oxide and carbon
dioxide.

Carbon dioxide accounts for 25% to 30% of stack emission from lime kilns.
There is a growing concern across the world on the emission of carbon dioxide

form the industrial units as it pollutes the atmosphere leading to undesirable
climatic changes.
The present invention emphasis on effective utilization of such generated useful
products to reduce environmental pollution and using the above two by product
as inputs. Such an action can lead to avoid the cost of incineration and also
generate revenue by making useful product.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose a process for
making ammonium bicarbonate using the waste generated at integral steel plant
which prevents air pollution.
Another object of the present invention is to propose a process for making
ammonium bicarbonate using waste generated at the integral steel plant which
will earn revenue after making.
A further object of the present invention is to propose a process for making
ammonia bicarbonate using waste generated at the integral steel plant which
conserves energy by avoiding incineration of ammoniacal liquor.
SUMMARY OF THE INVENTION
Theoretically, CO2 on dissolution in water to form a weak acid which is capable of
reacting with ammonia to form ammonium bicarbonate. Experiments were
carried to optimize the parameters for the production of ammonium bicarbonate
using these waste gases in following mentioned process:

Concentrate ammonia liquour (CAL) generated from coke oven gas after
quenching cooling and condensation in plant is first of all filtered. Through it
carbon dioxide is bubbled till the completion of the reaction. The flow rate of
carbon dioxide is maintained at 5 litre/minute. The container of CAL is cooled by
cold water (10-15 deg centigrade) as the reaction is exothermic. The final
temperature of the reaction mixture is maintained at 20-25 deg C. The reaction
mixture is further cooled at 8-12 deg C to obtain crystalline substance. The
product is then separated by filtration. The separated filtered product is washed
with ethanol.
The final product is then dried at 30-33°C. After testing the purity of the
ammonium carbonate it was found that purity is 99.5-100%. The composition of
ammonium carbonate so form was analyzed and results given below:-
Cu : 0.0002%
Fe : 0.0002%
SO4 : 0.0002%
CI : 0.0001%
Al : 0.0012%
Mg : 0.003%
Physical properties of ammonium bicarbonate are given below:
Appearance White Crystals
Smell With Slight Ammonia Odor
Melting Point 105-110 Deg C
Decomposition Above 36-40 Deg C
Specific Gravity 1.59
Solubility in water 17-18% at 20 Deg C

Industrial Applicability
1) For manufacturing of baking powder
2) For manufacturing of materials for fire extinguishers
3) For manufacturing fertilizer in agriculture

WE CLAIM
1. A process of making ammonium bicarbonate using waste materials
generated at the integral steel plants comprises:-
- preparation of concentrated ammonium (CAL) liquor by quenching,
cooling and condensation of coke oven gas;
- filtration of said generated CAL;
- collection of CO2 gas as produced by calcinations of lime stone in
plant;
- carbon dioxide is bubbled through filtered CAL;
- the container is cooled by cold water (10-15 deg C) and the final
temperature of the mixer is maintained at 20-25 deg C;
- the reaction mixture is further cooled at 8-12 deg C to obtain white
crystalline substance:
- the white crystalline substance is separated by filtration and
washed with ethanol;
- the final product is then dried out at 30-33 deg C;

2. The process of making ammonium bicarbonate as claimed in claim
1, wherein purity of ammonium bicarbonate is 99.5 - 100%.
3. The process of making ammonium bicarbonate as claimed in claim
1, wherein the ammonium bicarbonate appears as white crystals.
4. The process of making ammonium bicarbonate as claimed in claim
1, wherein the white crystals of ammonium bicarbonate have a
melting point at 105-110°C.

5. The process of making ammonium bicarbonate as claimed in claim
1, wherein the ammonium bicarbonate so produced decomposes at
36-40°C.
6. The process of making ammonium bicarbonate as claimed in claim
1, wherein the ammonium bicarbonate so produced have a specific
gravity 1.59.
7. The process of making ammonium bicarbonate as claimed in claim
1, wherein the ammonium bicarbonate so produced have 17-18%
solubility in water at 20°C.

Theoretically, CO2 on dissolution in water to form a weak acid which is capable of
reacting with ammonia to form ammonium bicarbonate. Experiments were carried to optimize the parameters for the production of ammonium bicarbonate using these waste gases in following mentioned process:
Concentrate ammonia liquour (CAL) generated from coke oven gas after quenching cooling and condensation in plant is first of all filtered. Through it carbon dioxide is bubbled till the completion of the reaction. The flow rate of
carbon dioxide is maintained at 5 litre/minute. The container of CAL is cooled by cold water (10-15 deg centigrade) as the reaction is exothermic. The final temperature of the reaction mixture is maintained at 20-25 deg C. The reaction mixture is further cooled at 8-12 deg C to obtain crystalline substance. The
product is then separated by filtration. The separated filtered product is washed with ethanol.