Download Build well with waste

status of Environment and Related luues
VoI.2 No.9
Build well with waste
T
he construction industry in
India is growing fast. The
increase in the demand for
homes and commercial space has driven
the sector to a growth rate of 9.2 per cent
every year, against the global average of 5.5 per
cent. Of late, concerns have been raised over the
way residential apartments and commercial buildings are
designed and constructed. Most of these concerns pertain
to energy, environment, sustainable construction
methods and technology.
~
What is eco-friendly building material?
Eco-friendly construction material are those
that have a lower effect on human health
and the environment when compared
with competing products that serve
the same purpose.
Eco-Friendly
Construction
material
Eco-friendly construction
alternatives
Eco-friendly construction alternatives should necessarily
have the following properties:
+ Derived from renewable source: like agricultural
waste.
The most common raw material used in construction are
of waste product: use of fly ash, iron ore
+
Re-use
steel, cement, glass, aluminum, plastics, bricks, etc. All
these are energy-intensive material and need to be
tailings etc.
transported across vast distances leading to more energy
+ Easy availability: for material not locally available,
consumption. It is not possible to meet the ever-growing
transport costs could be significant, affecting costdemand for housing by using only traditional energyeffectiveness.
efficient material like mud, thatch, timber, bamboo, etc.
+ Reduction in air, land and water pollution: use of
a.l.w. h. i.ch
iiioiir.es.ul
iiiiii
ts. in
. less or no VOC emission,
or those which may not
Thus there is a need for ,.
Properties of eco-frlendly building materials and techniques
result in water and lor
optimum utilization 0
the available energy
Renewable source
air pollution.
resources and raw
\
JBiodegradable
+Durability & life span:
material to produce
material which are
simple, energy-efficient, ~~~.:;
d'Reuse/recycle
durable and require
environment-friendly
Eco-friendly materials
low maintenance
Embodied ~
and techniques
~
+
and sustainable building
energy...-v
~Aidsenergy
Energy efficient:
alternatives. It is in this
context that the eco~
A
~
efficiency in building
Those which require
friendly construction
"
1f
"'\
less energy for
Local availability
Durability and
d ti'
likepre•a
I'fa
proucon,
materl'al gal'n
Reduction in air, water
I span
importance.
and land pollution
cast slabs.
_______________.m
_a.ten
...·
~--------------------------------------~ +Bio-degradable:
The demand-supply gap
In the last 50 years, the country's population has risen
from 330 million to 1.07 billion. Between 1999 and 200 1,
there was a requirement for 4,61,600 million bricks and
24,700 million roof tiles, a need that could not be met.
Against a housing requirement of200 million units, only
175 million are currently available, leaving a huge gap
between the need and availability.
material constructed from farm waste etc.
+ Reuse / recycle: products like aluminum and iron can
be reused.
These alternatives may serve all or some of the above
mentioned criteria but generally they should be costeffective so as to be financially viable for a potential
customer. Cost-effectiveness may depend on a variety of
factors like availability of raw material, its use for other
According to India's national report, by 2021 the country would face a housing shortage of 44.9 million units
-
~hri. Subir Hart Singh, lAS,
Principal Secretary to Government
~ousing Department
~ikas Soudha
~angalore 560001
02-04-2007
MESSAGE
With increase in population, burgeoning urban growth and general improvement in the
standard of living of the people, the construction industry in the country is witnessing an
unprecedented growth. While glass-and-aluminium structures are often seen as signs of prosperity
and well-being, there are simple, energy-efficient, environment-friendly and sustainable building
alternatives available.
Eco-friendly construction materials derived from easily available, renewable sources that are
durable and bio-degradable is available as a less expensive option. Judiciously used, this allows the
discerning citizen to build aesthetically-pleasing and comfortable homes and other structures while
making a statement of his commitment to nurture environment.
In this backdrop, a word of caution to every citizen building his or her house is that they make
sure of proper and timely disposal of construction waste generated during building dream houses in an
environmentally friendly way.
~l
!A
(s!'ir~in~
purposes (competing uses), maintenance requirements
and durability.
Conventional eco-friendly building material
--Bamboo, bamboo-based particle board & ply board,
bamboo matting
.-Sun dried bricks
'-Pre-cast cement concrete blocks, lintels, slabs.
Structural and non-structural modular elements
'-Calcined phospho-gypsum wall panels
'-Calcium silicate boards and tiles
'-Cellular light weight concrete blocks
'-Cementpaint
'-Clay roofing tiles
'-Water, polyurethane and acrylic-based chemical
admixtures for corrosion removal, rust prevention,
waterproofing
'-Epoxy resin system, flooring, sealants, adhesives and
admixtures
'-Ferro-cement boards for door and window shutters
'-Ferro-cement roofing channels
'-Fly-ash sand lime bricks and paver blocks
'-Gypsum board, tiles, plaster, blocks, gypsum plaster
fibre jute / sisal and glass fibre composites
'-Laminated wood plastic components
'-Marble mosaic tiles
'-MDFboards and mouldings
'-Micro concrete roofing tiles
'-Particle boards
'-Polymerised waterproofcompound
'-Portland pozzolana cement fly-ash / calcinated clay
based
'-Portland slag cement
2
~!>roximate
'-RCC door frames
'-Readymix cement concrete
'-Rubberwood fingerjoint board
'-Stonedust
'-Waterproofcompound, adhesive, polymer powder
Eco-friendly material / techniques and resource
centres
~ Bagasse board- BMTPC
}> Bricks from coal washery rejects CBRI, Roorkee
}> Building blocks from mine waste SERC
}> Burnt clay flyash bricks CBRI, Roorkee
}>Coircementboard CBRI,Roorkee
}>Compressed earth blocks BMTPC
}> EPS composites and door shutters CBRI, Roorkee
}> Fibre flyash cement boards BMTPC
}> Fibre-reinforced concrete pre-cast elements, wall
panels, blocks, manhole covers SERC
}> Fibrous gypsum plaster boards CBRI, Roorkee
}> Flyash cellular concrete, flyash cement brick, blocks
BMTPC
Kamataka Rajya Nirmana Kendra
(KARNIK), a Government ofKamataka
enterprise, is promoting cost-effective
building technologies through its
network of'Nirmiti Kendras' in the State.
It received a Government of India award
for utilization of fly ash as an innovative
building material on World Habitat Day
2006.
100 million tonnes of fly ash is generated in india's thermal power plant per annum
President A P J Abdul
KaJam's VISion of construction in tbe
Hon'ble
fntnre
''The building of the future will have
many new features of aesthetics and
convenience. Their energy sources will
be cleaner, based on solar power and
hydrogen. The glass panes of windows
and doors may have conducting polymers to regulate transmission of
solar rays into the room. The leakages during the monsoon will be a
thing of the past due to improved design and construction methods.
Above all, the time taken for construction ofhouses may be cut down to
several weeks or a few months instead of years. This would be
achieved thorough the use ofprefabricated structures and various other
factory-manufactured parts like advanced composite doors".
pollution. At present, fly ash is disposed
of by mixing it with bottom ash and large
quantities of water. The resultant slurry is
sluiced to settle in a setting pond. This
method makes heavy demand on land
and has the potential to cause ground
water pollution.
A remedy to this malady is to use fly ash
for the manufacture of bricks, Portland
pozzolana cement blocks, tiles, light
weight aggregates and hollow blocks.
Consisting mostly of silica, alumina and
iron, fly ash is a pozzolana a substance
containing aluminous and silicious
material that forms cement in the
presence ofwater. When mixed with lime
and water, it forms a compound similar to
Issues to be addressed by the construction industry include:
portland cement. The spherical shape of
. . Minirnizjng the use ofhigh energy material
the particles reduces internal friction
. . Use ofenvironment-friendly technologies
thereby increasing the concrete's
. . Minimize transportation ofmaterial
consistency. Improved workability also
. . Maximize the use oflocal material and resources
means less water is needed, resulting in
less segregation of the mixture. Though
. . Utilization of industrial and mine wastes for the production of
fly ash cement itself is less dense than
building material
portland cement, it results in a smoother
surface with sharper detail.
Building technologies meeting these principles could become
Mechanized manufacture of fly ash lime
sustainable and facilitate sharing or resources especially in using
bricks has already been undertaken in
energy more efficiently. This could minimize damage to the
many
parts of the country. The aim is to
environment.
utilize bulk quantities of fly ash and help
bridge the huge shortfall of bricks and
other building material required by the
}> Flyash lime cellular concrete CBRI, Roorkee
construction industry. At present in India, fly ash is being
}> Flyash lime gypsum brick BMTPC
used to manufacture ash blocks, floor tiles, terrazzo tiles,
cellular lightweight concrete (CLC), MCR tiles, door and
}> Insulating bricks from rice husk ash Central Glass
window
frames, interlocking blocks and flowerpots.
and Ceramic Research Institute, Kolkata
}> Jute fibre polyester BMTPC
}> Non-erodable mud plaster CBRI, Roorkee
}> Ploytiles CBRI, Roorkee
}>Timber from trees such as poplar, rubber, eucalyptus
BMTPC
}> Precast wall and roofing components CBRI, Roorkee
}> Prefab brick panel system CBRI, Roorkee
Let's now take a look at some of the eco-friendly
construction material which are in use in India.
Fly ash bricks
Almost 70 per cent ofthe total power generated in India is
through coal-based plants. This translates into 70 million
tones of fly ash generation every year and the production
may increase in the years to come. Management offly ash
is a huge problem as it is light weight and can travel by air
and result in reduced agricultural productivity and water
Fly ash products
There are about 50,000 tile and brick industries in the country.
3
Agro wastes generated in India (million tonnes / year)
90
Million tonnes / year
80
90
70
60
50
40
20
30
14
20
12
11
2
0
Series1
Bagasse
Rice husk
Jute
90
20
14
Rice wheat Groundnut
Straw
shell
12
11
1.4
1.6
10
Saw mill
waste
Coconut
husk
cotton stalk
2
1.6
1.4
Source: www.ics.trieste.it
4
A model house from unconventional building material
Cost comparison of buildings constructed
by conventional method and by using
Iron ore waste tailings products
Nam. of building
Pilot plant
Demonstration unns
•
•b
2. D.
dra
a Model house
Model house in R&D centre, Surathkal
Total
Totolcostof
Total cost of
building
constructed
using iron-ore
wut8talling
products
building If
constructed
Over'llil
savings
33.08.000
.01 of
conventlona'
prod....
36.00.000
135000
169000
1,49.000
1.87.000
34000
38.000
1.33.000
37 000
1.67.000
4123000
34.00.000
398000
2.92.000
The house has clean lines and a compact design. It looks like any other well-designed urban, low-cost housing
effort. What is different however is that it has been constructed out of unconventional building material. The doors
are made out of a wood substitute, the walls from iron tailing blocks, and the ceiling sports rafters made from ferrocement. A living room, a bedroom, a kitchen and bath-toilet make up the accommodation available in the house.
The house can comfortably accommodate a family of four members (see table for cost comparison between
constructing
with iron ore waste tailing products and conventional products).
,
The model house has demonstrated that iron tailing products work well; additionally, the technology can also be
replicated wherever there is a requirement for low-cost housing options. It offers, thus, a ray of hope for the
housing sector and economically backward sections of society.
bonded particle board which can bring down the use of
cement and brick. The cement board uses only 60 per cent
of cement and the remainder 40 per cent is eucalyptus
flakes and other agricultural waste. These boards can
withstand the damage caused by fIre and earthquake and
are waterproof too. They have four times the strength of
ordinary cement and require less water to set. Bricks
made from agricultural wastes are bio-degradable and
lastionger.
muddy red residue consists of alumina, iron oxide,
titanium oxide and small quantities of silica, calcium
oxide and alka\i. India generates over 4 million tonnes
of this by-product annually which is not otherwise put
to any use. Red mud is usually disposed of in ponds.
During the monsoon months this could lead to
contamination of ground water.
Red mud utilization
and 11.3 per cent liguin from its jute component Gute is
15 per cent of the total volume of the shutter).
RFPC is particularly suitable for door shutters, ensuring
siguifIcant savings in initial as well as maintenance
costs. There is a huge market for composite doors and
panels, with the potential waiting to be tapped both in
developing and developed countries.
Red mud jute fibre polymer composite: RFPC is a
substitute for wood-based panel products. It is made up
of easily available raw material like red mud, polymers
and natural fIbres. During aluminum production,
bauxite ore is digested with caustic soda, when most of
the aluminum passes into solution as aluminate. The
Sisal plant
RFPC composite contains ferric oxide, alumina and
titanium oxide from red mud, 82.5 per cent cellulose
Sisal fibre
-
Red mud jute fibre polymer products
Estimated agricultural waste generated in India exceeds 500 million tones Jler year.
5
-
Indo-Norwegian Environment Programme
Indo-Norwegian Environment Programme (INEP) is a
collaborative venture between the Government of India and the
Government of Norway. Through an agreement with the
Department of Economic Affairs, the two governments have
initiated pilot project in two Indian states, namely Karnataka and
Himachal Pradesh. The pilot programmes are designed to create
awareness on, and demonstrate corrective actions for serious and
~ent environment issues.
A project taken up in Karnataka under the INEP has addressed
Iron ore waste tailings problem in an effective way. As part of
this programme, the R&D Centre of the Karnataka Regional
R&D Centre, NITK, Surathkal
Engineering College at Surathkal has undertaken a project to
Key contributors .nd tMlr rot. for 1M Im. .m....lon of Iron
develop a technology for using the abundantly-available iron ore
0 ... lailing baed building products.
as raw material in the construction industry. The products already
...,."
manufactured include bricks, tiles and other material. The
of pIrt of 1hc ftmd
following products were developed at the R&D Centre with iron
ore waste tailings:
• Coloured bricks
• Roofmg tiles
• Glazed roofing tiles
• Bricks
• Studio pottery
• Hollow blocks
• Wall tiles
• Pavement bricks
• Floor tiles
Outcome of the project:
> Environ Charitable Trust' a special purpose vehicle for
technology transfer, entrepreneur development and
dissemination of information set up under Deputy
Commissioner, Dakshina Kannada and Udupi.
> Environmental protection and ecological balance by
converting industrial waste into useful building material
> Over coming the paucity of clay
> Preservation of topsoil for agricultural purposes.
> Promotion of scope for rura1 based industries.
> Transfer of technology to existing and new entrepreneurs.
Techno development in Iron Ore Waste Tailings based
building products such as Roofing tile, Decorative tile, Bricks,
Demo house constructed at
Pavement blocks, Wall tiles, Floor Tiles.
Nirmithi Kendra, Dakshina #Cannada
> Spinn off technologies like custom designed RCC & FCC
using Iron ore waste tailings products
rafters developed.
RFPC can also be used for furniture, flooring, electrical
switch box and insulation sheets for housing.
Plastic waste as building material:
With constant urbanization and industrialization, the
problem of discarded items and their disposal through
garbage has become a cause for concern. Items like
plastic bags and related material abound in garbage
dumps. The solution lies in recycling of plastic waste
after segregation.
Mixed and multilayer plastics containing several grades
of plastic material can be made into pallets. The pallets
can take the shape of tile flooring, waste containers,
planks, profiles, railway sleepers etc.
6
Plastic that cannot be further recycled can be used with
fillers for processing composites useful for applications
like fence posts, park benches, pallets and street furniture
as substitute to timber and concrete products.
Recycled PET: Unsaturated polyester resin from
recycled PET can replace the conventional high cost resin
for use in GRP products, polymer concrete / polymer
mortar, and industrial floorings.
Phospho-gypsum as building material:
Phospho-gypsum is waste generated by phosphoric acid,
ammonium phosphate and hydrofluoric acid-producing
plants. The fluoride content of phosphor-gypsum is a
source of land and water pollution. It is possible to
profitably utilize this pollutant for making cement,
In Kamataka, the requirement of clay for the tile and brick industries is about 3 million tonnes per annum,
Products developed at the R&D centre with iron ore waste tailings.
Interlocking Pavers
Hollow Blocks
Wall tiles
Penholders
gypsum board, partitions, ceiling tile, artificial marbles
and fiberboards.
Phospho-gypswn can be gainfully utilized in the
manufacture of expansive or non-shrinking cement,
super-sulphated and anhydride cement, simultaneous
manufacture of cement and sulphuric acid, as a hydraulic
binder, as set controller in the manufacture of Portland
cement, as mineraliser and in making gypswn plaster
boards and slotted tiles.
Pre-cast concrete frames:
Pre-cast concrete frame is one of the substitutes for
timber. Traditionally timber has been a vital building
material. Excessive deforestation is leading to an
Decorative pottery
ecological imbalance which could spell large-scale
disaster for mankind. In fact, adverse effects of
deforestation are already being felt in many parts of the
globe. It is necessary to take urgent steps to conserve our
forests. A substantial portion of wood is consumed in the
construction industry directly or indirectly. It is
imperative to reduce the consumption of timber in
building applications by identification, development and
promotion of alternate material which can partially /
completely substitute wood.
Pre-cast concrete frames are made out of cement, sand
aggregates and steel reinforcement. Fly ash and blast
furnace slag can also be used as raw material.
Commercial levels ofproduction can be taken up at a low
level of investment and with minimal labour training.
Advantages ofpre-cast concrete frames:
'-Conservation offorestreserves oftimber
'-Tennite-proof
'-Highquality and durable
'-Much cheaper than timber alternatives
'-Minimal requirement of raw material and high rate of
production
'-Water and fireproof
Gypsum board:
Lakkya dam in Kudremukha, completely
filled with iron ore waste tailings
Gypsum board is the generic name for a family of paneltype products consisting of a non-combustible core,
primarily of gypswn, with a paper surfacing on the face,
back, and long edges. Gypswn board is often called
drywall, wallboard, or plasterboard and differs from
The world's urban population is growing 2.5 times faster than the rural po!'ulation.
7
products such as plywood,
hardboard, and fiberboard
because of its noncombustible core.
Gypsum is a mineral found
in sedimentary rock
formations in a crystalline
form knows as calcium
sulfate dehydrate. One
hundred pounds of gypsum
rock contains
approximately 21 pounds
of chemically combined
water.
Gypsum rock is
mined or quarried and then
crushed. The crushed rock
is then ground into a fine
powder and heated to about 350 degrees F, driving off
three fourths of the chemically-combined water in a
process called calcining. The calcined gypsum is then
used as the base for gypsum plaster, gypsum board and
other gypsum products.
To produce gypsum board, the calcined gypsum is mixed
with water and additives to form slurry which is fed
between continuous layers of paper on a board machine.
As the board moves down a conveyer line, the calcium
sulphate recystallizes or rehydrates, reverting to its
original rock state. The paper becomes chemically and
mechanically bonded to the core. The board is then cut to
length and conveyed through dryers to remove any free
moisture.
Gypsum is also used as a raw material for some of the
products briefed as below:
Glass reinforced gypsum boards:
In building material, I wood can partially be replaced by
the use of glass reinforced gypsum (GRG). It is made
from glass fibre distributed evenly in gypsum matrix to
yield boards of 2m x 1m size with a thickness of4mm and
beyond. The material is pseudo-ductile in nature with a
flexural strength in the range of 20-35 Mpa and impact
strength of 10-26 N/mrn2. The boards can be utilized for
making door and window panels, false ceilings, partitions,
furniture, etc. These can be easily cut, drilled and other
wood working operations carried out as with the
conventional wood working tools. GRG boards can be
painted, polished and decorated by conventional means.
GRG offers advantages over wood and other
conventional board material, such as:
Pre-cost concrete frames
"'" It can be made to the required size and thickness
thereby reducing labour, wastage and jointing cost.
"'"Being isotropic in nature, it has eqnal strength in all
directions.
~ Any ornamental design can be incorporated at
nominal cost.
"'"GRG panels are about 50 per cent cheaper than teak
wood: the cost also compares favourably with
plywood and particle boards. Industrial wastes like
phosphor-gypsum and fibres from waste glass cu11ets
can be utilized to further reduce the cost.
Medium density fibre boards:
Various types of agro and agro-industrial wastes are
converted into fibers of the required size. The material is
mixed with a thermosetting binder and pressed in a
hydraulic press under specified conditions oftemperature,
pressure and time and the resultant boards are trimmed to
the required size. The product is waterproof, termite
resistant and fire resistant.
Source:
[1] Convertiog waste to wealth-Published by INEP
[2] Article of Dr.Rajendra Jagdale, Director-General,
Science & Techoology Park, University ofPune
[3] Wikipedia.org
[5] www.ics.trieste.it
[4]TERI
ENVISTeam:
Chakravarthi Mohan K.A.S., Co-ordinator, ENVIS
Centre,
Vijay Bhat, Programme Manager, INEP,
K.N. Koushik, IT Assistant.
ENVIS Centre - Karnataka
Department of Forests, Ecology & Environment, Govemment of Kamataka
010 Indo Norwegian Environment Programme, 2nd noor, Parisara Bhavan ,
No 49, Church street Banga/ore - 560 001. /{amataka
Ph: 080-2559 1515
email: [email protected] URL: http://www.parisaramahiti.kar.nic.in