Claims:WE CLAIM:

1. A Bench scale carbonization test apparatus comprising :

a steel box configured to be heated up to 11000C) which is covered from all sides after keeping the coal charge inside;

a raising hearth furnace with two sides wall heating facility;

an incinerating chimney connected over the top cover hole;

an automatic heating control and regulation system; wherein there is provided a hole onto the top cover of the said box at the middle (centre) for the exit of the gases during the carbonization.

2. The carbonization test apparatus as claimed in claim1, wherein the apparatus further includes bottom loaded raising hearth door.

3. The carbonization test apparatus as claimed in claim1, wherein the chimney is equipped with heating coil for incineration of the gases.

4. The carbonization test apparatus as claimed in claim1, wherein the automatic heating control and regulation system which provides multi-level segmented heating in the furnace.

5. The carbonization test apparatus as claimed in claim1, wherein the said steel box further includes another hole at the front face of furnace configured for inserting a plurality of thermocouples through the front face of the furnace into the box for the coke mass temperature measurement.

6. The carbonization test apparatus as claimed in claim 5, wherein the apparatus includes at least three thermocouples (with sheath), one for the temperature monitoring & control of furnace temperature (inside), second for the center coke mass temperature measurement and, third for over temperature protection.

7. The carbonization test apparatus as claimed in claim 5, wherein the apparatus further includes a platform mounted frame structure comprising of elevated furnace section with its opening at the bottom, closable by vertically moving hearth raising the charge into the heating cavity by mechanical arrangement.

8. The carbonization test apparatus as claimed in claim1, wherein the furnace body and door is made of welded heavy-duty mild steel.

9. The carbonization test apparatus as claimed in claim1, wherein the refractory lining of box and door is configured for withstanding continuous temperature up- to 11000C.

10. The carbonization test apparatus as claimed in claim1, wherein the said hole is made of high alumina tube provided at the top of the furnace to insert a chimney for taking out the gas.

Dated: this 17th day of February, 2016.

(N. K. Gupta) Patent Agent, Of NICHE,
For SAIL.

To,
The Controller of Patents, The Patent Office, Kolkata.
, Description:BENCH SCALE CARBONIZATION TEST APPARATUS

FIELD OF INVENTION

The present invention relates to the portable carbonization apparatus /pilot coke ovens. More particularly, the present invention proposes a bench scale carbonization apparatus with improvised box charging mechanism and gas burning mechanism.

BACKGROUND OF THE INVENTION

It is well known that the coking coal is charged in coke ovens for carbonization to obtain the final product of coke and associated by-products like volatile hydrocarbons, coal chemicals, tar etc. For the study of coking behaviour of coal charge, the bench scale /pilot coke oven tests are done.

To facilitate these tests, generally pilot coke oven of 200~300 kg coal charging capacity are used. This requires larger amount of coal charge, and, also, to complete one set of test it takes about 24 hours and involvement of 5 to 6 technical people. Prior to start the test such ovens requires 48 hrs heating cycle. Therefore, for quicker and less expensive tests a smaller, bench scale pilot coke ovens are used. Under this test pre-crushed coal (~ 80 % are less than 3.2 mm size) are kept inside a steel box and heated in the hot muffle furnace with controlled heating rate until the centre coke mass temperature reaches about
1000 0C. Gas generated during this process is taken out through a chimney and

incinerated. . After attaining the desired temperature, the box filled with red hot coke is taken out and quenched with water, and used for further laboratory tests. One such bench scale system with 2 kg charging capacity is common in various laboratories. During this test various constraints like uncontrolled rapid heating, leakage from furnace doors, non alignment of chimney, inefficient burning of by- product gas effluents etc, are faced. To counter these limitations, we designed smaller bench scale coke ovens of 10 kg charging capacity with less than 6 hrs charging cycle with 1 to 2 man-power requirements.

Currently in the experimental study of coke, according to research uses and purposes, there are 200 to 250 kg of large-scale experimental oven, there are 45 kg, 7 kg, 5 kg of different types of small test oven, but there are some drawbacks. As 7 kg, 5 kg when other small test oven test, the coal into a metal box, and then placed in a furnace heated metal box. These types oven faces constraint like excessive gas leakage from the furnace door, alignment of the chimney with the box, uncontrolled heating etc.

All conventional oven carbonization chamber pressure is to be controlled by the manifold pressure; manifold pressure is generally a fixed value. To ensure the safety of masonry oven coking chamber, requires the carbonization chamber pressure levels are either a positive pressure, negative pressure to prevent the occurrence of graphite masonry cracks between the blocks were burned inside, causing the furnace blow, and therefore required to measure each year more than twice the manifold pressure and the pressure at the bottom of the carbonization chamber. When the bottom of the carbonization chamber pressure measurement choose the traditional oven suction tube just below the carbonization chamber number (maximum suction intake pipe directly below), measured (coking end of the minimum amount of gas) at the end of the carbonization chamber of coke, the measurement In the carbonization chamber door, Piezometric measure inserted into the hole, and manifold pressure readings while readings. Final manifold pressure set point to measurement results appear at the bottom of the carbonization chamber pressure manifold pressure value when positive 5Pa prevail. In the actual measurement process, we found the traditional method of measuring the carbonization chamber pressure on 7.63m coke oven is not applicable. The reason is that the traditional coke oven is measured at the end, when the carbonization chamber of coke ripe, smooth airflow when the load on the door can be read into the carbonization chamber pressure situation, and measuring 7.63m coke oven carbonization chamber bottom pressure Coking is the whole process of measuring, at the beginning of coking coal carbonization chamber material as well as the water does not evaporate, pressure tube is tightly pressed wet coal, measured pressure at this stage is basically a fixed value, can not grasp the carbonization chamber near the furnace wall, near the door of pressure changes.

OBJECTS OF THE INVENTION

The principle object of the present invention is thus directed to provide an electro- mechanical carbonisation test apparatus to simulate the coking process with commercial coke ovens.

A further object of the present invention is directed to providing an improved mechanism for reduce man power and time requirement for carbonisation test.

A still further object of the present invention is directed to provide a suitable apparatus which requires less coal samples to complete the carbonisation test.

A still further object of the present invention is directed to provide a suitable apparatus which have less gas leakage during the carbonisation test.

A still further object of the present invention is directed to provide a mechanism for efficient door sealing for the furnace

A still further object of the present invention is directed to provide a suitable system for properly incineration of the gases which are generated during carbonisation test.

A still further object of the present invention is directed to provide a suitable system for the automatic heating control for carbonisation test.

A still further object of the present invention is directed to providing a suitable system in which coal can be charged in varying degrees of bulk density.

A still further object of the present invention is directed to provide a suitable foundation for the raising heart type furnace for the carbonisation test

A still further object of the present invention is directed to provide mechanism to obtain the centre coke mass temperature of the coal charge during charging.

SUMMARY OF THE INVENTION

In accordance with the stated objective, the present invention discloses a bench scale coke oven used for lab scale carbonization test which includes a number of features which provide more ease in carbonization test. In existing bench scale carbonization system which has charging facility horizontally has door leakage problem while in our invention we have given a raising hearth as door , laying at the bottom, which stops gas leakage through door due to the fact that hot gases has tendency to rise upward . Further no significant openings are provided at any other face except opening at the top for the chimney. Due to the fact that coal filled steel box rises vertically upward there is no problem chimney alignment with the opening at the box top. An automatic incineration facility is also provided at the top of the chimney which incinerates all the gases which are coming out during the tests.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

Fig. 1 illustrates front elevation view of the apparatus in accordance with the present invention;

Fig. 2 illustrates side elevation view of the apparatus in accordance with the present invention;

Fig. 3 illustrates top elevation view of the apparatus in accordance with the present invention;

DETAIL DESCRIPTION

Coke is a solid carbon fuel and carbon source used to melt and reduce iron ore in the production of steel. In one process, known as the “Thompson Coking Process,” coke is produced by batch feeding pulverized coal to an oven that is sealed and heated to very high temperatures for 24 to 48 hours under closely- controlled atmospheric conditions. Coking ovens have been used for many years to convert coal into metallurgical coke. During the coking process, finely crushed coal is heated under controlled temperature conditions to devolatilize the coal

and form a fused mass of coke having a predetermined porosity and strength. Because the production of coke is a batch process, multiple coke ovens are operated simultaneously.

The melting and fusion process undergone by the coal particles during the heating process is an important part of coking. The degree of melting and degree of assimilation of the coal particles into the molten mass determine the characteristics of the coke produced. In order to produce the strongest coke from a particular coal or coal blend, there is an optimum ratio of reactive to inert entities in the coal. The porosity and strength of the coke are important for the ore refining process and are determined by the coal source and/or method of coking. In order to eliminate the prior art difficulties like heat loss, non-uniform burning, gas leaks etc caused by the carbonization chamber of coke oven door smoke problem, and for accurate evaluation of coking of coals, the coke oven has been modified to include specific features as exemplary embodiments such as herein described.

In an exemplary embodiment, the coal is kept into a steel box and be heated (up to 1100 0C) from two sides only (as done in coke ovens) as shown in Fig.1. This system is helpful in simulating commercial oven heating. The box (Fig. 1, part 8) is covered from all sides after keeping the coal charge inside There is a hole ( 20 mm dia.) onto the cover of the box at the middle for the exit of the gases during the carbonization,

Another hole (dia. 20 mm) is done at the front face of the box (Fig.3), at the height 100 mm from bottom. Purpose of this arrangement is, to insert the thermocouple properly and to minimize the gas leakage from the box through this hole. Accordingly, there are two holes at the furnace body– one at the top and another at the side of the furnace (Fig. 1, part 6). These holes are aligned with the holes provided at the box.

The purpose of the hole at the top of the furnace is to insert a chimney fitted with heating coil for exit and incineration of the gases, generated during the coal

carbonization test. The hole at the side of the furnace is used to insert the thermocouple inside the coal charge.

As per another embodiment, there are three thermocouples (with sheath) provided – one for the temperature monitoring & control of furnace temperature (inside),second for the centre coke mass temperature measurement and, third for over temperature protection. The platform mounted frame structure has been provided comprising of elevated furnace section with its opening at the bottom, closable by vertically moving hearth raising the charge into the heating cavity by mechanical arrangement (as shown in Fig. 1).

As per yet another embodiment a motorized lifting arrangement has been provided at the bottom side of the oven to raise and down the door along with box filled coal charge (about 30 kg total weight of filled box) during carbonization process.

As disclosed above, one hole, made by high alumina tube of inner diameter

25mm (approx.) has been provided at the top of the furnace to insert a chimney for taking out the gas. Another hole (at the front face of furnace) at the height
100 mm. from the hearth level, is made for inserting the thermocouple through the front face of the furnace into the box for the coke mass temperature measurement .

Transformer and control panel house was kept inside the frame structure. Furnace body and door was made of welded heavy-duty mild steel. Proper refractory lining/ arrangement has been done to protect the heating elements from fumes generated from the heating of coal charge during carbonization. Refractory lining of chamber and door is capable to withstand continuous temperature up-to 11000C. Using the output of thermocouples an automatic heating control and regulation system is designed using program logics and software which further provides multi-level segmented heating in the furnace.

A trolley is used to bring the box filled with the coal charge from the coal preparation unit to the oven side, and to bring the box filled with hot coke after carbonization to the quenching place. A detachable chimney has been provided for the proper incineration of the gases coming out from the furnace during coal carbonization. At the top of the chimney arrangement comprising of heating coils has been made for proper incineration of produced gases.

INVENTIVE STEP

The inventive steps and features of the system of carbonisation test apparatus are:

1. There was no lab scale coke oven/ carbonisation test apparatus available using the concept of raising hearth furnace.

2. Due to the fact that its door position lying at the bottom and absence of any other opening, gas leakage has been controlled significantly.

3. As the charging box is kept at one fixed position onto the heart and no further displacement is take place during the whole testing tenure, no issue of alignment of chimney appears.

4. This innovation consists of special type of chimney which burns out most of the gases produced during carbonization.

5. Programmable heating in multiple segments

6. Due to control heating and enhanced scaling ratio with commercial ovens it provides better ease in carbonization test.

Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the

art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.