Green business of NR needs exploitation
By Dr N Yogaratnam
|
Dr N
Yogaratnam |
The elastomer market is dominated by renewable natural rubber and
non-renewable fossil-fuel-derived synthetic rubber, in some applications
they are substitutes and in others, complements. Tyre production
accounts for over 50% of elastomer consumption and 60% of natural rubber
consumption. The current share of natural rubber in total tyre
production is unlikely to change much. Rubber cannot realistically be
replaced in tyre production, nor can tyres themselves be replaced by a
different product. Many general rubber products also appear very
difficult to displace or replace.
Taxonomy
One key factor in the relationship between any activity and the
environment is that it is impossible to consider any individual activity
without reference to the overall consequences; nevertheless, it is
useful to introduce a taxonomy. In the case of the rubber industry it is
helpful to break down the activities which impinge upon the environment
into those associated with (1) the production of the raw material, (2)
the transformation of the raw material into finished products, (3) the
use of such products in service, and (4) the final recycling or disposal
of the products. Many studies relating to the last-named, such as
investigations of the scrap tyre problem, fail to recognize the
importance of the other elements which may either amplify or mitigate
the problem. It is inevitable that we tend to base our analysis upon
natural rubber, frequently in comparison with synthetic rubber, but many
of the factors (such as factory emissions, product service and ultimate
disposal) apply to all elastomers.
Renewable vs non renewable
In most discussions on the environment, resources are divided into
renewable and non-renewable categories. The former includes most natural
products. The latter includes most mineral resources, although many of
these are recyclable, and fossil fuels. Some countries tend to consider
their large hydroelectric capacity as a green resource. Fossil fuels are
not only non-renewable, but their combustion contributes to increases in
global carbon dioxide levels and a possible greenhouse effect which may
lead to higher ocean levels and the loss of global land mass.
The present pattern of consumption of natural and synthetic rubber
remains a relatively constant 40% and 60% respectively, of the total
elastomer consumption. The main advantage of SR is that it can be
mass-produced to meet a wide range of specifications, although in
reality more than 80% of SR products could be produced using NR. Certain
industrial products, however, require the unique properties of NR with
the largest single market being the tyre industry, which accounts for
ca. 70% of world NR consumption. NR is the strongest of all rubbers and
has excellent dynamic properties (e.g. resistance) which accounts for
the fact that aircraft tyres comprise 100% NR. In other aspects such as
tolerance to environmental damage (e.g. by ozone and oils) NR competes
less favourably with SR.
In addition to its unique dynamic properties, NR has the advantage
that it is a renewable, non-polluting source of elastomer as opposed to
SR, which is manufactured from crude oil. Furthermore, in a world where
increasing consideration is given to the environmental costs of
production, NR compares much more favourably with SR.
For example, production of 1 t of NR requires 15 to 16 Gj of energy
compared to 108 to 174 Gj for SR, depending on the grade of SR produced.
In addition to the high energy costs, SR production is also a source of
pollution whereas NR cultivation has few detrimental effects on the
environment. It is the processing rather than cultivation of NR that has
the potential to pollute, although this can be minimised through
effective process management.
CO2 business
There has been increasing national and international concern over the
accumulation of Green House Gasses (GHG) particularly CO2 and its effect
on global warming. CDM of UNFCCC provides opportunity to seek
remunerations for the environmental services provided by NR plantations.
A rubber tree can fix about one MT of CO2 carbon during its 30-year
cycle. A hectare of rubber will therefore provide about 300 MT of CO2
for trade. The total land extent of rubber in Sri Lanka is forecast to
increase to 140,000 ha by year 2021 and to 153,000 ha from the present
extent of 127,000 ha. Therefore, by year 2021 the total CO2 available
for trade in Sri Lanka would be about 42,000,000 MT and by 2031, would
be about 45, 900,000 MT of CO2, if all rubber plantations are made
eligible to receive credits for the environmental services provided by
the rubber industry.
Also, rubber trees add about 23 MT/ha of CO2 to the soil through
annual leaf fall, but part of which decomposes and re-cycled to the
atmosphere. About 23 Mt of carbon(84 MTof CO2) are removed from the tree
as latex yield in 30 years, most of which are used in value addition and
therefore retained and not lost. Unlike hydropower or similar projects
for emission reduction, planting trees for CO2 sequestration is subject
to environmental changes and hence exhibit some uncertainty. The present
market rate for a MT of CO2 varies from US$ 5 to 20.
Additional carbon trading benefits from rubber include; a) Rubber
wood as a source of renewable energy, replacing fossil fuel, provides
equivalent CO2 for trading,b) In power generation, 3kg of biomass is
required to compensate one kg of fossil fuel. Therefore, the biomass of
a hectare of rubber at the end of 30 years would replace 64 MT of fossil
fuel, c) The emission reduction potential by biogas generated from
rubber factory effluent is around 12,000 MT per year, and d) Power
factor correction and factory modernization for electricity saving in
rubber processing industries also qualifies for carbon trading by
emission reduction
Soil conservation
Trees such as rubber play an important role in conservation of soil
and water resources, they not only provide a long-term canopy, which
protects the soil from erosion by wind and rain, but they also root over
a greater area, depth and duration than short-term crops and so help
bind and protect the soil. Litter fall from trees adds organic matter to
the soil, which improves the surface soil properties so that rainfall
infiltration is increased and surface run-off is reduced.
In Sri Lanka, rubber tends to be cultivated on land where few crops,
other than tea, can be grown commercially and in the major rubber
growing areas as much as 50% of the rubber lands have slopes of between
45 to 60%. Although tea is also grown on steep land, it fails to offer
the same degree of protection to the soil as rubber, with an average
soil loss of 35 MT ha-1 yr-1 compared to just 10 MT ha-1 yr-1 for
rubber.
In terms of soil conservation, the properties of rubber plantations
have been likened to that of native forests. Forests can recycle about
8.33 t of dry litter per year as compared to 3.7 to 7.7 t yr-1 in rubber
plantations; it is only in the older rubber lands where nutrient
recycling via litter approaches that of native forest ecosystems.
Agronomy
NR does not impoverish the land upon which it is grown. Fertiliser
inputs are very low and the surrounding soil appears to be enriched by
the abundant leaf fall. Furthermore, biodiversity remains remarkably
high in rubber plantations in marked contrast to most forms of
monoculture. Excellent agronomic techniques assist in the conservation
of the environment within rubber plantations. Measures include
terracing, slit pitting, bunding and mulching and the growth of
leguminous cover plants between the rows to assist with nitrogen
fixation. Biomass burning is now discouraged during replanting.
Moreover, it is possible to grow a wide variety of crops during the
tree’s immature period, further enhancing its environmental credentials.
Forest conservation
The rapid loss of forest cover in Sri Lanka had been a major cause of
concern in terms of the environmental impact. The forested area in Sri
Lanka has declined from 70% in 1900 to less than 23% in early 2000,
which translates into an annual rate of deforestation of more than
40,000 ha yr-1. This compares with a replanting rate of only 2000 ha
yr-1. Parallel with the decline in forested area has been the rapid
increase in population, rising from 11.5 to 18.5 million over the same
time period.
Green tyres
Studies show that 20 to 30 per cent of a vehicle’s fuel consumption
and 24 per cent of road vehicle CO2 emissions are tyre-related. Green
tyres can reduce fuel consumption by five to seven per cent and have a
shorter cost amortisation period in comparison to other fuel-saving
technologies in cars. To help calculate the potential savings motorists
can make, Lanxess has launched a new fuel savings calculator, and says
it serves as “a particularly valuable accessory in these times of record
fuel prices.”
India
As Europe prepares for a mandatory tyre labelling regime, India may
follow suit. In tyre labelling, it is imperative for manufacturers to
spell out details concerning fuel consumption, wet grip and noise
classification. This is seen as an important part of the drive towards
cleaner emissions.
“India has an aggressive agenda in reducing carbon dioxide emissions
like the rest of the world. It is here that tyre makers have a leading
role to play especially with their kind of strong knowhow,” it has been
said.
As one of the world's leading suppliers of specialty chemicals,
Lanxess has been supporting the cause of green tyres. While Europe (and
South Korea) will be the first to kick off labelling towards the end of
this year, other countries will have to fall in line eventually. “Our
experience is that when it comes to tyre regulations, it is applicable
to all especially when it involves exports to Europe. The market is
globalising and that is why tyre labelling is as important in regions
like India,” says an Indian tyre expert.
Not too many car owners realise that tyres contribute to 20-30 per
cent of fuel consumption in an automobile. This means that every fifth
visit to a gas station is attributed to the tyre's rolling resistance.
“This is nothing but the tyres heating up during use. That wasted
energy can be reduced with high performance, innovative materials,” he
explains. Tyre labelling is important as “it makes the performance
visible.” To a layman, a tyre represents a black, round object when
there is so much more within in terms of technology. Further, labelling
gives the buyer the chance to understand better what a tyre is all
about.
“Customers need to know what they are spending their hard money on.
Green tyres have enormous potential in reducing fuel consumption,” he
has said. This becomes even more relevant in the current scenario of
high global crude oil prices.
Study undertaken
Lanxess carried out a study in Europe where it looked at 12,500 km of
average driving per year. It was seen that with green tyres, the fuel
savings were nearly €100 alone annually. “If you pay an additional €50
for a green tyre, you recover your investment in 25,000 kilometres or
two years,” it has been said.
Despite the current crisis in Europe which is literally putting the
heat on the automobile industry, tyre makers are gearing up for the
labelling transition. There is a voluntary drive already under way in
Japan, while Brazil and the US are also working on this initiative.
|