Past Developments
:
It is a common experience in our country
that our thought-processes, and resulting technological
developments, are greatly influenced by their counterparts
in the developed world. And brick industry is no exception
to this rule. Therefore, while attempting to predict
the future of our brick industry, study of the European
(particularly English and German) and American brick
industries becomes inevitable. For this purpose, brief
account of some important events, trends, trade practices,
technological developments, etc. prevalent in the European
and American brick industries during the last three
centuries [ 1] is given below :
1) The Great Fire of London ( 1666
A.D. ) which devastated the city and resulted into the
Rebuilding Act of 1667, really gave a shot in the arm
of the then low-key English brick industry. The Act
banned use of wood ( being highly combustible ) and
recommended exclusive use of bricks and stones for reconstruction.
This resulted into an unprecedented demand for bricks
and made its use very popular ( and even a status symbol
!) all over England.
2) Brickmaking was a seasonal operation
then. The season began in April and ended in October.
Brick earth was dug in the Autumn and piled up in heaps
to 'weather', especially by the frost. In the Spring,
the material was tempered, i.e. trodden or turned with
spades to make it evenly plastic. Moulding was then
done on a table using either sand or water as a release
agent, and the surplus from the wooden mould was sliced
with a stick or a cutting wire on a bow. The moulded
bricks were carried to the drying ground (sometimes
between two small boards called pallets ) in 'herringbone'
pattern. When the first row was partly dry, a second
was laid across it and when that was ready, a third
and so on, until a height of ten courses was reached.
This pile of drying bricks was known as a 'hack'. Straw
covers were provided over the hacks to protect the drying
bricks from rain and excessive solar heat. Drying used
to take upto 6 weeks. The bricks were then fired in
'clamps' or 'scoves' or 'skotch kilns' using cinder,
coal and/or wood as fuel. The clamp size varied anywhere
between 20,000 and 100,000 and the firing took 2 to
6 weeks from cold to cold.
3) Red colour was aspired to by nearly
everyone planning to construct a brick house or add
a brick chimney to his timber house.
4) Horse-driven pugmill was the first
labour-saving piece of equipment which emerged at the
end of the 17th century. It was shaped like a barrel
containing a vertical shaft with projecting blades and
was used for blending of clays in wet state.
5) By the middle of the 18th century,
popularity of red colour started declining. Comments
such as "..... the colour is fiery and disagreeable
to the eye; it is troublesome to look upon it; and in
the summer, it has an appearance of heat which is very
disagreeable; for this reason it ( red brick ) is most
inappropriate in the country..." ** started appearing
and use of red bricks became unfashionable. Thereafter,
hues of pink, yellow-orange, yellow-brown, buff, green,
blue, etc. started appearing in the market, which were
generally described as 'grey'.
6) In 1784, Brick Tax was introduced
in England to help partly meet the expenses of the American
War of Independence. In the beginning, bricks of all
sizes attracted the same tax and therefore, there was
a tendency to produce as large a brick as possible,
even upto a size of 12" x 6" x 3¼".
However, the subsequent Act of 1803 put a double duty
on bricks of volume more than 150 cubic inches - which
made production of 10" x 5" x 3" size
bricks a very attractive proposition. Finally in 1850,
the Brick Tax was abolished altogether.
7) In America, until the end of the
18th Century, burnt bricks were imported from England,
which was considered profitable ballast on vessels which
had light cargoes. However, wood was the more common
choice of locals and English colonists for building
their houses and shacks (and this tradition continues
even today ).
8) Open-faced brick buildings lost
their charm in the beginning of the 19th century and
stone-dressed or stuccoed ( i.e. rendered ) walling
became the "in thing". This obviated the need
for producing and / or using good quality burnt bricks
along with sand-lime mortar, because, in the end, all
brick faces were to be plastered over. However, as the
quality of brickwork deteriorated, public opinion changed,
and in the end, by about 1860, unrendered brickwork
once again regained its lost popularity.
9) Till around the middle of the 19th
Century, brickfields were mainly the concern of reformists
and missionary clergymen because of the degenerate behavior
that went on in them. Child labour, drunkenness, unhygienic
working and living conditions and exploitation of all
sorts was order of the day. Few other industries of
the time could match the earthy and uncivilized 'image'
of the then brick industry. The owners of brickfields
were usually portrayed as 'brutish, troublesome, hard-drinking,
rollicking, dirty-tongued' mortals and the moulders
as 'ones who raised their families with the earnings
of their wives and children and spent their own income
entirely on drinking'. Work used to start at as early
as 4.30 a.m. and continue till 8 p.m., although 6.00
a.m. to 6.00 p.m. was the more common practice. Labourers
were paid by piece-rate and a moulder 'gang' could mould
anywhere between 1,500 and 3,500 bricks in a day, depending
upon its composition and strength. However, the quality
of the then English brick was far superior to its American
and German counterparts.
** Quoted from " Complete Body
of Architecture," 1766, by Isaac Ware
10) The second-half of the 19th century
saw the birth of numerous brickmaking machines and firing
techniques, fuelled mainly by the ever -increasing demand
for bricks and shortage of skilled labour. Britain's
brick production doubled during the period 1850 and
1900 and the industry could operate year-round and provide
steady employment. Initially, the mechanisation drive
met with more commercial failures than successes. Also,
machines were looked upon as job-stealers and several
attempts of sabotage ( like dropping a steel spanner
into a grinder or blowing-up a steam engine ) were reported.
However, the initial aversion to mechanisation and fear
of failure soon gave way to openness and finally, a
preference for advanced / state-of-the-art technologies.
11) A list of major inventions during
the 19th century is given below in chronological order
[ 1, 2 & 3 ] :
1813 - Manually operated soft-mud moulding
machine developed by Kinsley
(England )
1828 - Development of piston or box-type
horizontal reciprocating
extruders
1840 - First tunnel kiln patented by
Yordt in Flensburg ( Denmark )( However, the
kiln became techno-commercially viable only after 1947
)
1849 - Extruded hollow brick developed
by Henry Roberts ( England )
1854 - Vertical extruder with die developed
by Carl Schlickeysen ( Germany )
1856 - Annular continuous kiln developed
by Friedrich Eduard Hoffmann, an Austrian by
birth, patented in Germany in 1858. It was circular
in shape with a chimney in the
centre surrounded by a semi-circular vaulted channel
divided into 12 chambers.
1860 - Semi-dry process for pressing
shale dust developed at Accrington ( England )
1865 - Development of horizontal auger
(or worm) extruder and mobile cutter, the latter
developed by Gebruder Sachsenberg (Germany )
1867 - First chamber dryer built at
Mensing ( Germany ) ( However, the dryer
attained wider acceptance only after 1894, when the
finger car was
invented by Keller in Germany )
1870 - Re-press for wire-cut bricks
developed by Bennett and Sayer ( England )
1876 - Bull's trench kiln design patented
by W.Bull, an Engineer ( England )
1927 - Habla kiln invented by Alois
Habla (Germany)
Present Technology Status :
Technically, burnt clay bricks fall
under the category of 'Heavy-Clay Products' forming
a major part of the 'Ceramic Industry'. Heavy-clay products
are those that are mainly made from a single clay or
similar mineral with very little additions of other
raw materials. They are principally used in structural
work, hence they are often called 'Structural Clay Products'.
The first heavy-clay machinery in India
was introduced at Jeppu ( near Mangalore ) in 1865 -
around the same time it started gaining popularity in
Europe. However, during the last 150 years or so, our
Brick Industry has made very little real progress w.r.t.
development and / or adoption of 'appropriate' technological
solutions. This is despite the fact that -
(a) the roof tile production process
- which is the torch-bearer of the heavy-clay technology
in India - has taken firm roots in all parts of the
country ( e.g. Calicut - Southern India, Balaghat -
Central India, Morbi - Western India, Allahabad - Northern
India, Raniganj - North-Eastern India and Samalkot -
Eastern India ) and
(b) a number of dedicated Government
R & D Institutions and Promotional Agencies are
rendering yeoman service to the industry.
The present production of burnt clay
bricks in India is estimated at about 120 billion bricks
per year coming from at least 1,00,000 brickfields (
of which at least 40,000 are moving / fixed chimney
/ Hoffmann / High-draught kilns ) scattered all over
the country. Although Ceramic Products like glazed tiles,
crockery, sanitary ware, refractory bricks, etc. are
being made with the most advanced / state-of the-art
technologies, the state of the brickmaking technology
in India is far from being satisfactory. The present
work culture of our brick industry is no different than
the one that existed in Europe during the mid-19th century,
as mentioned earlier. Majority of the units still employ
age-old hand-moulding, sun-drying and clamp, scove or
moving chimney kiln burning methods. Use of roller crushers,
extruders and Hoffmann kilns for brickmaking has remained
restricted to the Mangalore-Calicut coastal belt only,
while use of fixed chimney kilns and high-draught kilns
is mainly prevalent in the Northern and North-Eastern
and some Southern States.
There have been attempts in the recent
past to set up oil and coal-fired tunnel kilns in Kannur
and Erode districts of Kerala and Tamil Nadu, respectively.
However, they are yet to report commercial successes.
More recently, 13 Vertical Shaft Brick Kilns ( VSBKs
) have been designed, constructed and made operational
at Datia, Tekanpur and Gwalior (M.P.), Mohuda and Asurmunda
( Orissa ), Palakkad ( Kerala ), Pune, Nimbut and Amravati
( Maharashtra ), Varansi and Bareily ( Uttar Pradesh
). By far, they appear to be the fastest, cleanest and
most fuel-efficient kilns developed for firing upto
15,000 bricks per day. Of late, a few improved versions
of fixed chimney / high-draught kilns (incorporating
arrangements to increase the existing heat-transfer
rates, decrease the heat losses and contain pollution
more effectively ) have also been put to commercial
tests.
Present Entrepreneur Psychology :
The present psyche of the Indian brick
fraternity can be best described by the term 'mechanisation
phobia'. The phobia is due to the techno-commercial
failures of a large number of semi-mechanised / mechanised
brick plants set up so far. The main reason for these
failures has been the lack of insight on the part of
entrepreneurs as well as machinery suppliers and technology
providers as to 'what makes a brick plant click in the
real world'. Most people mistake the brick industry
for one, which involves mere mechanical operations,
while in reality; it is a unique process industry. Therefore,
an unbiased evaluation of technical feasibility (including
raw material testing ) and economic viability ( including
reliable market survey and proper selection & training
of personnel ) of a project is a must for guaranteed
commercial success.
On one hand, this fear psychosis, coupled
with the high cost of capital in the country, is making
the entrepreneurs extremely cautious towards mechanisation.
While on the other, the recent 'Brick Regulation '96'
of the Ministry of Environment & Forests is forcing
them to convert their existing clamps / moving chimney
kilns into cleaner and more fuel-efficient kilns. Also,
factors like fast depletion of deposits of 'good' brickearth,
ever increasing problems of labour management, decreasing
profit margins, etc. are inducing entrepreneurs to consider
immediate adoption of affordable, cost-effective, dependable
and simple technologies.
Shape Of The Things To Come :
Since the early seventies, the world
is becoming increasingly aware of the ill effects of
smoke, acid rain, desertification, 'green-house phenomenon',
extinction of rare species, disintegration of the ozone
shield, etc. on our environment. This has lead to 'sustainable
development' becoming the buzzword of the day. In line
with this thinking, all long-term developments in our
brick industry are expected to be influenced by the
'principle of sustainability' alone. 'Sustainable development'
means 'development that meets the needs of the present
without compromising with the ability of future generations
to meet their own needs'. Even though we in India are
equally concerned about (and feel responsible for) the
well-being of our future generations and our planet,
the omnipresent scarcity of resources and influence
of the traditional thought is bound to limit our choices
to solutions of 'appropriate technology' alone in the
short run.
These short and long-term trends are
described below in brief.
Short-term Trends ( 2000 to 2010 )
:
1) Seasonal operation to continue,
by and large, upto 2005 followed by gradual replacement
with all-the-year-round operation
2) Adoption of 'functionally useful'
products and production systems without much concern
for aesthetic / decorative considerations
3) Wide-spread use of clay preparation
machinery, simple extruders, drying sheds and material
handling equipment
4) Introduction of hot floor dryers
and chamber dryers
5) Conversion of existing moving chimney
kilns of more than 15,000 bricks per day capacity into
fixed chimney / high draught / Hoffmann kilns
6) Conversion of existing open clamps
and annular kilns of less than 15,000 bricks per day
capacity into vertical shaft kilns
7) Continuous improvement in design
and operation of fixed chimney, vertical shaft and high
draught kilns ( including use of setting equipment/
fork-lifts / trolleys, etc. for loading / unloading
)
8) Entry of open-cured semi-dry-pressed
calcium silicate bricks (including flyash bricks ) and
soil bricks
Long-term Trends ( 2011 - 2050 ) :
1) All-the-year-round operation
2) Strict compliance with environment
regulations and quality standards
3) Product diversification (facia bricks,
brick pavers, hollow blocks, split tiles, etc.)
4) Stiff competition to burnt clay
bricks from calcium silicate bricks
5) Introduction and anchoring of stiff-extrusion
and semi-dry pressing technologies
6) Wide-spread use of chamber and tunnel
dryers
7) Introduction and anchoring of tunnel
kiln and process automation systems
References :
[1] Woodforde John & Paul Routledge/Kegan,
Bricks to Build a House, 1976
[2] Bender Willi, 'From Craftsmanship to Industry -
The Development of Brick
-making Technology in the 19th Century', Tile &
Brick International
( No.1,2,3 & 4 ), 1996
[3] Searle Alfred B., Modern Brickmaking, 1931
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