Overview of Brick Industry in Kathmandu Valley, Nepal
its relevance to VSBK technology
ranks as one of the most picturesque countries in the world, free
from the vagaries of modern days technological developments. However
with the penchant to keep pace along with the developed world, a
pall of crisis is slowly and steadily looming large in the form of a
highly polluting atmosphere. Apart from
Brick Kiln, Nepal
numerous brick kilns dotting the landscape are major sources of
obnoxious emissions. Being well aware of the future consequences,
Swiss Agency for Development and Cooperation along with SKAT
Consulting and Development Alternatives with active support from His
Majesty's Government of Nepal is reintroducing a "cleaner and
greener" brick production technology – the "Vertical Shaft Brick
digging its roots in Nepal, numerous refinement and upgradation
generated in India perfected a scaleable model, ready to be
replicated anywhere in the world. In comparison with conventional
brick producing means this technology boasts of lower emission
standards, reduced energy consumption and economically viable means
of brick production, besides creating a socially equitable status
amongst the brick community.
are still and will continue to be the preferred walling material due
to their abundan availability and pleasing nature widespread use of
fired clay is also dependent on the availability of clay deposits
for brick making found on agricultural land situated in valley
floors and estuaries. Availability of water and market vicinity
augment the operation of large number of brick kilns in the
types of brick making technologies are practiced in the Kathmandu
valley. These vary from simple intermittent type manual operations
to continuous type and semi-mechanized ones. The simplest technology
was introduced in Nepal in the early 1950’s and slowly replaced the
traditional clamp kilns. An attempt to modernize the brick
technology was made by the Nepal Government with technical and
financial assistance of the People’s Republic of China in 1970 by
introducing the Hoffman kiln technology. However, due to high
initial investment cost and requirement of trained staff, this
technology did not become popular in the private sector.
successful adaptation of Vertical Shaft Brick Kiln technology in
China, it was introduced into Nepal in 1991 under a GATE – GTZ
programme together with Ceramics Promotion Project. The energy
saving potential was clearly demonstrated having an energy
consumption of 1 MJ/Kg of fired brick. Thereafter another two shaft
unit was set up in the Terai region. These shut down for lack of
sector in Kathmandu valley, whose functioning and growth is directly
linked to construction activity, is presently in the eye of a storm.
Negative rate of growth in construction activity in past few years
has resulted in a proliferation of brick kilns, which have
reappeared in the Valley with spectacular speed raising serious
concerns about the deteriorating air quality. It has been reported
that brick kilns, producing in excess of 350 million bricks are the
major single source of SO2 and SPM in the environment of Kathmandu
valley; contributing over 60 percent of the emissions. The solutions
to this problem must take into account the following competing
factors that are at work.
demand for burnt bricks continues to grow fuelled by an increased
demand for housing in the Kathmandu valley. The customers have
preference for burnt brick as the primary walling material; even
though alternatives such as concrete blocks are increasingly being
used for boundary and partition walls
increase in supply of burnt bricks is ensured by willing
entrepreneurs who jump at any opportunity for making quick profits.
The entry barrier for new opportunistic traders is low.
government of Nepal is aware of the serious environmental problems
created by the brick kilns. The efforts are intensified by
environmental watchdog organizations and activists, who are going
hands with communities to limit the growth of kilns and force them
to "clean up" or "close down". The government has set into motion
the task of setting environmental performance standards for kilns
but enforcement, even of existing legislation, continues to be weak.
of VSBK Technology
search for appropriate technology solutions as an alternate to
conventional Bulls Trench Kiln and open clamps led to the VSBK
technology as a possible alternative.
Shaft Brick Kiln (VSBK) is an energy efficient and environment
friendly technology for fired clay brick production. It essentially
consists of one or more rectangular, vertical shafts within the kiln
structure. The shafts are 1 to 1.25 metres wide with nominal lengths
varying between 1 to 2 m. Shaft heights can be varied to hold from 8
to 13 batches depending on green brick crushing strength. The inside
surface is a brick wall lined with refractory bricks to minimize
heat loss. Gap between the shaft and outer kiln wall is filled with
insulating materials – burnt bricks and burnt coal ash etc.
Provisions for peep holes for thermocouple probes are provided along
the shaft height to monitor the position of fire as well as
temperature profile of the kiln. Rectangular rows of dried green
bricks and crushed fuel (coal) are carefully stacked into batches,
and are continuously loaded from the top of the shaft. Each batch
typically contains four layers of bricks set in a predetermined
heating cycle for the green bricks is raw material specific
(pre-heating, vitrification and cooling down) and is normally
completed within 24-30 hours. A batch of bricks is loaded and
unloaded every 2-3 hours; requiring round the clock operations and
supervision. Unique features of VSBK are:
High energy efficiency
Environment friendly operations
Uniform quality of production
of VSBK in Nepal
to the ever increasing demand of bricks, around 250-300 moveable
chimney and clamp kilns dot the Kathmandu valley,
Brick Kiln (VSBK), Nepal
a single most, major source of environmental pollution in the
valley. The resultant emission of harmful gases like SO2, CO2, CO,
NOX and respiratory particulate matter severally affect the
surrounding habitat and also contribute to global warming. It also
has detrimental effects on the flora and fauna affecting the means
of nurturing sustainable livelihoods.
emanated during the firing process has made old handicrafts,
exquisite temples and other archeological treasures dusty and dull.
The only silver lining in this problematic cloud is the awareness
created in the minds of people searching for a better and cleaner
environment. Hsis Majesty’s Government of Nepal has passed orders to
close all the movable chimney BTK’s and has advised the brick owners
to switch over into new technologies fulfilling all the energy and
environmental regulations. Kathmandu valley is a bowl shaped area
surrounded by high mountains. The only possible way to save the
habitat is either dissipate the obvious smoke beyond the
valley; which is "mission impossible" due to the more
than 1000m high mountains or adopt technologies which reduce
the SPM content considerably creating a "Green Valley".
fulfill the second criteria various options like VSBK, gas and
electric fired tunnel kilns, roller hearth kilns are available.
However judging from the investment and case of operation, VSBK is
the most appropriate brick firing technology for Kathmandu valley
–Nepal. The most important factors which merit credit over all the
modern available technologies are:
gives unmatched flexibility of operation, good quality and
substantial saving in energy consumption. It economizes on fuel
costs achieving savings of between 30-50 percent when compared with
other brick firing technologies such as clamp, moveable chimney or
fixed chimney BTK’s.
► Economic viability
Brick production using
VSBK technology is a profitable business due to substantial fuel
savings. Initial investment although is high compared to fixed
chimney BTK of similar capacity, but it can be recovered in a single
season operation through fuel savings only. Operating capital
requirement is very low and returns are within 2 days compared to 24
days in BTK’s.
► Environmental friendliness
Installation and operation of VSBK requires very little land.
Construction of multiple shaft production units further enhances the
ratio of land use to production output. As VSBK firing only requires
coal or lignite, deforestation of rural areas can be controlled.
Additionally benchmark operation of VSBK lead to highly reduced
emissions compared to clamps or moveable / fixed chimney BTK’s.
for Energy Conservation
Maintenance of the
Kathmandu valley, higher fuel savings are likely due to poor regard
to quality. Significantly the bricks in Kathmandu are only 55 mm
thick and through use of internal fuel, further savings may also be
possible using VSBK technology. The specific consumption of bricks
fired using the VSBK technology is likely to be 1 MJ/Kg of brick or
late than Never
Nepal project has in the short space of five months, been successful
in setting up two pilot kilns. Preliminary energy and ecnvironmental
monitoring exercises indicate saving of approximately 30% energy and
an 80% reduction in emission of suspended particulate matter.
now being drawn up to further customise the VSBK technology package
to suit local conditions and refine the strategy for more widespread
advent of the VSBK Nepal project, we sincerely hope to see a
"Green and Clean" Kathmandu in the next couple of years; helping
our future to nourish and grow in a healthy environment.
Back to Contents