ICA_Feb 07.pdf - Roof & Facade

Energy
the fuel source to Orimulsion with positive results. Estimated fuel cost saving of an
existing conventional power plant is about 25% (compared to using fuel oil), after
necessary modifications to the base unit to meet environmental discharge limits.
For fast-developing countries, like China (PRC), energy needs and developments
are increasing at very steep rates, so their growth will be dependent on their ability to
cope with ever-increasing electrical demands. In order to satisfy such increasing power
demand, a country such as China (PRC) will need to import vast amounts of relatively
cheap alternative fuel to meet power-generation requirements. Though China has an
abundant supply of coal, the extraction rate could not cope with the raising demand and
safety of the coal mining industry remain as a major concern. Orimulsion seems to be
a viable solution to their energy needs.
However, two recent developments have somehow disrupted the production and
export of Orimulsion. First, the invasion of US army into Iraq and the subsequent
unrest caused the crude oil prices to shoot up beyond US$60 per barrel. It is believed
that the selling price of Orimulsion to the Chinese oil firms is approximately US$200
per ton. This makes Orimulsion, which is pegged to the price of coal, extremely
attractive, and the Venezuelan suppliers are quickly realising that they are subsidising
foreign power generation. Second, the recent internal labour unrest in Venezuela has led
to a major strike in PDVSA. Most of the engineers were fired as punishment, and so
Orimulsion fell out of favour with the key political leaders. As a result, the government
of Venezuela is trying to ‘wind down’ to the Orimulsion programme.
In fact, one of the production sites has already been shut, while the other remaining
site will likely follow suit by the end of December 2007. Most Orimulsion supply
agreement contracts have been terminated, and no new supply contracts of Orimulsion
will be signed. The only exception is the continuation of the supply of the emulsion fuel
to two of China’s (PRC) oil firms. This is due to the strong political ties among China,
Cuba, and Venezuela. The government of Venezuela explains their abrupt action by
indicating that the reserved used for Orimulsion production is actually identified as
‘extra-heavy crude oil’, not bitumen. Hence, it is not deemed a ‘precious reserve’. In the
coming years, it is not expected that the use of Orimulsion in Asia will re-surface,
unless there will be moderate adjustment to the pricing of the bitumen-based emulsion
fuel and the labour relationship between PDVSA and the government has improved.
Multiphase Superfine Atomised Residue (MSAR)
MSAR is a new stable oil-in-water emulsion fuel system developed by Akzo Nobel
Surface Chemistry AB of Sweden. MSAR has only less than two years of marketing
history, and it is not clear if there are confirmed customers outside Canada yet. This
product is protected by license agreements and patents held by Akzo Nobel and Colt
Technologies Inc. of Canada. Quadrise Canada has the exclusive rights for the use of
MSAR emulsion fuel technology in Canada.
The composition, stability and burning efficiency of MSAR are very similar to that
of Orimulsion. Both are expected to be practical and cost-effective alternative fuels
based on bitumen to replace fuel oil and natural gas. Both required FGD facilities to
remove the sulphur oxides formed when burning. However, MSAR technology offers
two major differences of production and operation aspects compared to Orimulsion.
Two advantages of using MSAR over Orimulsion include:
• The fuel can be customised from various feed stock, ranging from bitumen to heavy
hydrocarbons, offering an ideal disposal method for refinery heavy residue.
• It is manufactured on site, thereby avoiding transportation risks involved in shipping
the emulsion fuel to end users’ locations.
Basically the MSAR process involved setting up a compact production module at
customers’ site to generate the emulsion fuel via mixing local bitumen feed, water and
Petroleum distillation towers
surfactant. The product can then be stored away for power generation later. In the
MSAR process, the heavy oil residue / bitumen particles are milled to approximately
3 - 5 microns in diameter. This is somewhat smaller than the typical atomised droplets of
50 microns in fuel oil. It is also smaller to those produced in Orimulsion technology.
Currently, Quadrise Canada is marketing MSAR with an added advantage to potential
customers, and identifying security in supply is a consideration that must be pondered
when selecting bitumen-based emulsion fuels.
While this new option of bitumen-based fuels may not solve the availability of energysource
problems, it does look attractive for countries that operate huge refineries and
already have experience handling heavy residue and also have on-site FGD facilities. It
is no surprise that two state-owned refineries in India are believed to be interested in
such a model to reduce fuel cost. For the smaller power stations, this technology may
prove to offer no advantages due to the lack of adequate economical supply of bitumen/
heavy residue, or the savings may not be attractive compared to the required initial
capital investment.
Summary
Orimulsion production and sales to China and Japan was gaining very strong
momentum in since early 2000. However, this program was halted abruptly elsewhere,
and China is currently the only customer that will have the supply agreement contract
honoured till end 2007. The continued supply of Orimulsion looks unlikely unless the
price is adjusted to reflect its true value currently. MSAR is another option for big
refineries in Asia. It is manufactured on-site and does not have as many supply or
transportation problems and restrictions. However, this technology is costly at initial
stages as a process hardware unit (capital investment) is required to be installed before
benefits can be realised. Indian refineries are keen on taking up such options because of
the advantage via economy-of-scale.
The use of bitumen as alternate energy source in Asia has begun, and its usage will
definitely grow as it provides an option to fight increasing fuel costs. As it turns out, the
most-likely users willing to make the switch are also the biggest fuel consumers. ❏
This article was submitted by Mr. Goh Hong Hoo, Senior Lecturer, Nangyang Polytechnic, School
of Chemical and Life Sciences who is an expert in bitumen and petroleum-related products.
A Bit About Bitumen
NATURAL Bitumen is a mixture of organic liquids that consists of very large
hydrocarbon molecules, mainly comprising of multiple cyclic aromatics. It is
black, highly viscous and sticky. In other words, it is basically thick oil that does
not flow at moderate temperatures or cannot be pumped without being heated
or diluted. Many geologists believe that the natural bitumen deposits are formed
from the remains of ancient, microscopic algae and other prehistoric once-living
plants. These organisms died, and their remains were deposited in the mud on
the bottom of oceans or lakes where they once thrived. Under the pressure and
heat of burial deep in the earth, the remains were transformed over time into
crude petroleum materials and bitumen.
Geographically, bitumen is found throughout the world. The greatest
potential resources are identified mainly in Venezuela, Canada and Russia.
However, the actual available sources could be much larger. It is believed that
many possible bitumen deposit occurring locations are not documented, unless
they can meet economical extraction/market conditions. Hence, it will not be a
surprise if more bitumen / heavy oils reserves are declared later. The bitumen
deposits in Orinoco Oil Belt, a part of the Eastern Venezuela basin, represent
nearly 50% of the world documented and extractable bitumen reserves at 1.2
trillion barrels. In Alberta, Canada natural bitumen deposits represent up to about
35% of the world reserves. Logically, these two countries have the most active
research programmes to extract bitumen, and they also to make full use of their
reserves potential.
Bitumen is primarily used for paving roads. Other conventional uses include
general waterproofing products (including boats), roofing felt and for sealing
flat roofs. Bitumen emulsions are two-phase systems consisting of bitumen, water
and one or more additives to assist in the formation and stabilisation of the
emulsion. Such emulsions help to avoid the requirement of heating since they
are ready to use products. As a result, there is less atmosphere pollution and less
heating energy used for laying and maintenance of roads. Recent technological
development also allow bitumen emulsions to be used as a commercial boiler
fuel in power plants in Canada, China, Japan and Germany. Such bitumen-based
fuel is formed via mixing bitumen with fresh water and an alcohol-based
surfactant. The resulting mixture has properties very similar to the conventional
fuel oil or natural gas, thus making it easier to be transported and combusting
fully in air.
Raw bitumen has proportionally more carbon atoms than hydrogen atoms.
Elemental analysis of bitumen shows that most contain 82 to 88% Carbon; 8 to
11% hydrogen; 1 to 6% sulphur and 0 to 2 % of oxygen and nitrogen. This heavy
carbon weightage property makes bitumen having a tendency to generate heavy
particulates in the effluent when burned. Bitumen may be waxy, and also contains
several heavy metals such as vanadium, nickel, chromium, mercury, lead and
arsenic, selenium and other toxic elements. It is whole soluble in carbon disulfide.
The chemical composition of bitumen is extremely complex. A complete analysis
of bitumen would be very laborious and also impractical, if not possible. In
general, however, it is possible to separate bitumen into saturates, aromatics and
resins.
Bitumen is also produced in bottom-residue fraction of the fractional
distillation of crude oil in the refineries. It appears as the heaviest fraction and
with the highest boiling point. From the properties described above, it is not
difficult to imagine that there will be an array of problems compared to other
petroleum-based energy sources with respect to exploitation, transportation,
storage and refining of bitumen. This is reflected in the relatively high cost
involved in extraction and processing bitumen, as well as the physical limitations
of production capacity. ❏
ICA Volume 1 Issue 1 2007 9