Pot Furnaces

Gas-fired pot furnace in Ferozabad

Activities under the pot furnace component focused on two distinct aspects, (1) Unit level activities aimed to fine-tune technology, provide back-up support, and optimize investment costs and (2) Cluster level activities that included information dissemination and creating conducive conditions which would help in replication of the efforts made at unit level.

The project finalized design specifications for different capacities—4.8 to 6.72 tonne per day—of pot furnaces. The detailed specifications for various pot furnace components such as recuperator, burner and quarl, gas line, air line, crown, and furnace base were finalized. Modifications and improvements in pot furnace base regarding use of better material to minimize corrosion by molten glass during pot breakage helped in extended life of furnace base. However, the option of using other refractory material was kept open. The gas and air line was also modified to suit the requirements of the furnace. These efforts helped in reducing the furnace cost by around US$ 10 000 (Rs 5 lakhs). Recuperator, burner, and refractory are the three major cost heads and efforts are on to further reduce the initial cost. However, based upon the experience gained during the period, it was decided that the entrepreneurs should have the choice of using different materials of construction, depending upon their financial capacity and willingness to invest. The industry can be provided with knowledge that will enable them to take informed decisions.

Gas-fired pot furnace in Ferozabad

Parallely, efforts were made for disseminating information about the energy efficient design to other prospective entrepreneurs. One-to-one meetings and presentations at various cluster level meets were the modes used for spreading the message. As a result of these efforts, one of the units came forward to set up the first replication unit. The agreement was signed in July 2003 and the unit was commissioned in September 2004. Technical assistance to the unit was provided in terms of detailed design, drawings, material procurement, construction, operation, and fine-tuning. The performance of the replication furnace was monitored to verify energy savings. These values dwelled close to the demonstration furnace. Based upon the success of this replication, a few more units showed interest and now there are 9 more units with TERI designed NG (natural gas) fired pot furnaces.

Muffle furnaces (pakai bhatti)

Workers at pot furnace site in Ferozabad

The intervention in muffle furnaces primarily focussed on providing technical assistance to the owners who came forward to set up the gas fired furnaces. Assistance was provided with regard to (1) support during furnace construction (2) optimization of operation for proper combustion (3) trouble shooting in muffle furnaces to improve upon low temperatures and irregular temperature distribution and (4) calibration of rotameters for monitoring gas consumption. The efforts undertaken in the cluster resulted in disseminating the NG fired concept in the cluster. By end of March 2006, there were nearly 75 NG fired pakai bhatties operating in Firozabad. However, rate of penetration of NG fired pakai bhatties in future will depend upon many other extraneous factors like availability and pricing of gas, supply of gas to smaller furnaces by GAIL, continued availability and price of coal and proposal of shifting of furnaces outside the congested localities. TERI initially made efforts to bring together the furnace owners in the form of a cooperative to get gas and operate collectively but due to above mentioned unresolved issues; the efforts could not be pursued further. About six groups of pakai bhatti owners had shown consent to form/register as cooperatives. The brainstorming session organized by TERI with a few experts to study the feasibility of cooperatives for muffle furnace owners indicated that a formal industrial cooperative model will be very difficult to realize, given the ground situation in Firozabad.

Other activities undertaken related to muffle furnace dissemination were:
Local nodes (masons) identified for construction of muffle furnaces
Efforts for reducing construction costs of muffle furnace
Modifications in the burner earlier designed by TERI
Brochure prepared in Hindi for circulation amongst owners
Preparation of a small video film titled “ Through the smoke screen ..” on the gas fired muffle furnace