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Vertical Shaft Brick Kiln

 

A Vertical Shaft Brick Kiln (VSBK) is an energy efficient technology for fired clay brick production. This technology originated in China and has about 10,000 kilns running at present. In India, the VSBK technology has introduced at a pilot scale in 1996 and presently 20 kilns are operational. It essentially consists of one or more rectangular, vertical shafts within the kiln structure. Rectangular arrays of dried green bricks and crushed fuel (coal) are carefully stacked into batches, which are loaded into the shaft from the top and finally batches of fired clay bricks are removed from the bottom end. During this process, the batches of bricks pass through the preheating, firing and cooling zones before they reach the shaft exit.

This technology relies on the principle of counter correct heat exchanger in order to achieve high thermal efficiency. When the shaft lid is in the closed position, the entire kiln functions as a chimney. The heating cycle for the green bricks is between 22-24 hours. A kiln with 2 shaft of 1.25m x 2m - produce upto 10,000 bricks in a day, which equals to the annual brick production of around 2.5 million.

The VSBK technology considerably economizes on fuel cost, with savings of between 30 to 50% when compared with other common firing technologies such as clamps or Bull’s Trench Kilns. Pollution levels are extremely reduced compared to other prevalent methods of brick firing.

Areas of application
VSBK bricks are suitable for all fired brick applications. Well-designed loading and unloading mechanism ensure uniform size, sharp edges and corners and less breakage during the production. These qualities make these bricks more suitable for exposed brick masonry and high strength load bearing applications. Wire cut extruded VSBK bricks with compressive strength upto 300 kg/cm2 are ideal for such applications.

Advantages

Energy efficient Save 30% to 50% on fuel cost when compared to other brick firing technologies
Economically viable A profitable business opportunity, with 50% recovery on investment made, within 1st year of operation.
Requires low initial investment Required relatively less capital for infrastructure and construction
 Requires extremely low working capital Production cycle can start with 50,000 hands on stock of green bricks, whereas fixed chimney BTK’s requires around 5 lakhs of green bricks. Secondly, the working capital required in case of VSBK is considerably low. This is because the saleable product (fired bricks) is obtained in 22-24 hrs, compared to 20- 24 days which is required in any other conventional brick firing system.
Low gestation period Construction of kilns can be completed within 60 days with immediate start of production
Environment friendly Much lower emissions (e.g. SPM – 22 to 37 mg/nm3)

Requires less land for kiln construction Unlike the horizontally spread in the BTK, VSBK requires vertical firing concept reduces the land requirement considerably

Flexibility in production The batch type firing system gives an unmatched flexibility in production. It allows you to plan a precise production schedule with exact amount of bricks to be produced, depending upon the market demand.
High quality and less breakage More than 90% of the bricks produced belong to 1st grade, where as in a BTK 2nd and 3rd grade brick are produced in significant quantity. Well designed loading and unloading system controls the breakage within 2-3% of the production.

Development Status
Commercialized

Technical Data

Annual production 2,000,000 (With 2-shaft kiln of size 2mx1m) Based on 220 days of operation
Land requirement 2000m2(excluding area required for moulding of bricks)
Electricity 7.5 KVA, only while using mechanised lifting

Nos. of jobs created (workforce)

44 (1 Supervisor, 30 skilled, 13 unskilled)

Economic Data
Cost benefit analysis of Biogas with different fuels

Infrastructure Rs 500,000/- (For Kiln and office space)
Equipment Rs 200,000 (For Kiln accessories, vertical hoist, generator)
Training and commissioni Rs 65,000/-
Total Rs 765,000/- (US$ 15,300)
(These cost do not include cost of land, as it varies considerably from place to place)

Business
VSBK is highly profitable for small and medium scale building material producers. A capital investment of about Rs. 8 lakh can yield a production value of Rs. 20 lakhs. The gestation time for kiln construction and commissioning is only 60 days. The technology is provided by TARA Nirman Kendra, an associate of Development Alternative Group.


Transfer forms

 Turnkey basis


For further information, please contact :

Mr. Subroto Roy
Senior Business Development Executive
Development Alternatives
B-32, TARA Crescent
Qutab Institutional Area
New Delhi – 110016

Tel : 91+ 11+ 696-7938, 685-1158
Fax : 91+ 11+ 6866031
Email : tara@devalt.org
sroy@devalt.org
URL : www.devalt.org

 

 

 

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