Asad Ashfaq PRESENTS

FLYASH BRICK – AN ENTREPRENEUR’S APPROACH

FROM :INSTITUTE OF MANAGEMENT SCIENCES, PHASE 7 HAYATABAD PESHAWAR.

Material science is a complex composite, arising out of in-built judgment in orienting the characteristics and constituents of various products to serve the human race; and depending on the nature’s gift, tapping the same for the application of human need.

Bricks made out of clay is one such product which proved its credence since the dawn of civilization. Brickwork is established as an age-old construction media right from the thatched house to multi-storeyed buildings. Nature’s kind-heartedness in gifting the humankind with its bountiful resources, of course, has a threshold limit and the utilization of clay has reached such a point in construction.

This potential resource has been over tapped, unmindful of the consequences, as a result of which (except in limited pockets of some river delta regions) barren lagoons have replaced vast stretches of erstwhile fertile land. Added to that, soil degradation and disturbances in ecology are threatening the very rudimentary pillars of welfare.

In countries like India, where about 65% of the population is still living in economically weaker and rural segments, clay is unanimously the cost effective building material to make the walls and floors of their huts. But irreparable exhaustion has taken place for such versatile product, leaving no chances of replenishment for millennia to come.

In West Bengal, the industry estimate of registered clay brick manufacturers stands at around 8,000 in numbers. There is almost an equal number of unregistered brickfields taking the State level aggregate to approx. 15,000 brickfields. Considering that the minimum annual production of a brickfield is around 30,00,000 pieces, the total clay brick production of the State works out to approx. 4,500 Crore pieces.

Taking into account that 10% of this production is carried out

using silt available along the river banks, approx. quantity of clay bricks manufactured through excavation of top soil may be assumed at approx. 4,000 Crore pieces, which destroys 9.77 Crore cum top soil annually as under :-

4000 Crore pcs x 0.08632 cft/brick = 345.28 Crore cft or 9.77 Crore cum of top soil weighing 12.80 Crore MT.

For converting this estimated volume to flyash bricks, the minimum quantity of flyash required annually would work out to :-

4000 Crore pcs x 0.0033 MT/brick x 50% (by weight) = 6.60

Crore MT Therefore, daily requirement of flyash is envisaged at =

1,80,000 MT So, even theoretically, most of the flyash can be recycled by

brick manufacturers, which in turn would save precious top soil as well as abate carbon di-oxide emission, the process being devoid of sintering.

DISTRICT WISE ESTIMATED NO. OF FLYASH BRICK UNITS IN WEST BENGAL

DISTRICT WISE ESTIMATED NO. OF FLYASH BRICK UNITS IN WEST BENGAL

40 Units

12 Units

5 Units

2 Units

15 Units

7 Units

5 Units

8 Units

10 Units

15 Units

10 Units

5 Units

4 Units

2 Units

ESTIMATED TOTAL NO. OF UNITS = 140 ESTIMATED TOTAL NO. OF UNITS = 140

Properties of Fly Ash brick / block

Compressive strength : 50 - 160 kg/sq.cm.

Water absorption : 10 – 15 percent

Density : As pure mix : 1.4 gm/cc.As mortar brick: 1.6 – 1.8

gm/cc.

Coefficient of softening (depending on water consistency factor) : 2 -15 percent

DurabilityOnce the hydrated compounds and related mineralogies form out of flyash constituents upon activation with cement or lime and gypsum, no further reactivity is evident either internally or with extraneous media like ground and air laden chemicals. This results in dimensional stability and enhanced weather resistance of pozzolanic products.

Pozzolanic applications have been well established as durable materials of construction for the last 2 – 3

millennium and Fly Ash Concrete is nothing but an improved version of this established pozzolanic chemistry.

Environment FriendlyNotwithstanding the techno-economic virtues, Fly Ash bricks comply with the criteria for

environmentally friendly products and eligible for Carbon Emission Reduction earnings in terms of Kyoto Protocol on account of the main raw material being an industrial by-product and the manufacturing process being devoid of sintering or auto-claving is totally energy conservative.

What made Fly Ash brick/block attractive?

a) Fly Ash bricks do not lose strength unduly even on soaking in water continuously. Hence plastering is optional rather than necessary.

b) On account of size accuracy, plastering can be rationalized adding additional savings on cement.

c) Well cured fly ash bricks absorb 4 – 12% of water only.

d) On account of less absorption, rationalization of plastering & mortar, a finished fly ash brick wall is lighter and cheaper in

comparison to finished clay brick wall.

e) Fly ash bricks can be made to order with engineering properties comparable to cement concrete, befitting for specialized applications such as canal lining, dam construction, water tanks, etc.

Why the Ministry of Environment & Forests, Government of India published the notification no : S. O. 763 (E) dated : 14th. September, 1999 ?

“ Whereas it is necessary to protect the environment,

conserve top soil and prevent the dumping and disposal of flyash discharged from coal or lignite based thermal power plants on land ;

And whereas, there is a need for restricting the

excavation of top soil for manufacture of bricks and promoting the utilization of flyash in the manufacture of building materials and in construction activity.”

How flyash bricks and blocks are suitable alternative to ordinary burnt clay bricks ?

The manufacture of flyash bricks and blocks does not

require excavation of top soil and utilizes flyash generated by thermal power stations instead.

Flyash as all knows has its own problems of disposal

and is otherwise a social menace with recycling through production of building materials being the preferred utilization.

Flyash bricks and blocks being chemically bonded does not require sintering and dispenses with the need for coal – a non-renewable fossil fuel. Further, as need for burning the bricks and blocks is absent, the manufacturing process is totally environment friendly and contributes substantially to reduction of carbon di-oxide emission - a harmful greenhouse gas which is responsible for global warming.

Flyash bricks and blocks have the following advantages over ordinary burnt clay bricks :-

Better finishHigh StrengthLess water absorptionNo efflorescenceLower unit weight and less load on foundationReduced energy consumptionNo excavation of top soil – which is otherwise suitable

for cultivationLower cost of bricks and blocksLess mortar consumption

Why is the flyash brick/block industry suffering in the State of West Bengal ?

The notifications published by the Ministry of

Environment & Forests, Government of India for 100% utilization of flyash bricks, blocks and tiles for all construction works within a radius of 100 kilometres of a coal/lignite based thermal power plant is not being adhered to by both the Government and private construction agencies in the absence of monitoring by statutory authorities and/or imposition of penal provisions as provided by law. Even thermal power plants generating the flyash do not use flyash bricks, blocks and tiles mandatorily in all its construction works.

The flyash bricks and blocks industry is burdened with unfair tax regime vis-à-vis the clay brick manufacturers, who can get away with evasion of VAT, Central Excise, ESI, PF and other statutory duties or taxes inspite of doing enormous harm to the environment through excavation of top soil, consumption of non-renewable coal and emission of carbon di-oxide.

Some other bottlenecks that are acting as hurdles to the development of this sun-rise industry in West Bengal are as under :-

a) Entrepreneurs are entering the business on a hype of making “fast money” devoid of knowledge about the process technology and marketing constraints.

b) There is less consciousness and focus on product quality leading to a wide variation in attributes amongst different manufacturers.

c) Cannibalisation amongst manufacturers due to inadequate demand for the product and very slow evolution of market in absence of use by Government departments and agencies under their control.

d) Buyers need to be realistic while drawing up specification and price so that manufacturers are not compelled to compromise on the binder, which constitutes 60 – 70 percent of raw material cost of the product.

Nature always summons for transformations in material science and that is how balance is atoned in resource availability to fulfill the varietal needs of human race. Though talk of habits and attunements are popular arguments, particularly in countries like India while responding to advent of innovative products, need forces to compromise first and get appeased next.

The availability and use of clay is exactly at such crossroads.

Lack of technological and material alternates held up clay users all these years inspite of dire necessities and pressures. The profuse availability of fly ash on one hand and FAL-G technology on the other have emerged to offer respite on clay front. Hence it is time to say good-bye to clay bricks and welcome flyash brick manufacturing with a big hand for its techno-economic virtues.

THANK YOU