Fossil carbon resources

Chemical exploitation of renewable raw materials has a long tradition. Before the utilization of the fossil carbon resources coal and petroleum, they were the exclusive source of organic raw materials. Even today, a wide range of chemicals is produced on this basis, e.g. natural rubber, cellulose, fatty acids, ethanol and essential oils, citric acid, enzymes and antibiotics. In terms of quantity, around 8% of organic chemicals are recovered from renewable raw materials. Of the 20 Mt of renewable raw materials used annually, oils and fats have the largest share, amounting to some 40% (Figure 3.55). 

Carhon in the environment is sequestered by plants/biomass in a 1-10 year time frame by photosynthesis using sunlight as the energy source - one year if agricultural crops are used and 10+ years for tree plantations. This is in balance with the rate and timescale of use of the plant/biomass resources to make chemicals and products, and ultimate disposal with release of carbon back to the environment. In contrast, the rate and timescale of carhon sequestration to fossil resources (oil, coal, natural gas) is millions of years, whereas the use and ultimate disposal is in the 1-10 year time frame. This makes the use of fossil carbon resources out of balance and unsustainable. This represents the fundamental, intrinsic value proposition for using biobased carbon from plant/biomass, agricultural crops/residues and algae as opposed to fossil carbon resources. 

Some raw materials of adhesives are derived from petrol. Therefore, if petrol resources are depleted, the production of adhesive cannot be maintained. This depletion is an ultimate situation, but even the price rise of petrol can give serious and negative impact to adhesive industries. An alternative option is the use of other fossil carbon resources such as coal. Coal is more abundant than petrol in terms of reserve. However, its carbon dioxide emission per unit is larger than that of petrol. Anyway, true sustainable societies cannot be realized while finite fossil resources such as petrol or coal are widely and often used. Energy consumed in the production process of adhesive and its curing process may be derived from fossil fuels too. 

Most polymers can be made from renewable resources at a cost. For example polyethylene, the major commodity polymer used in packaging, was one of the earliest biopolymers. For some years ethylene was manufactured from sugar by fermentation to alcohol, followed by dehydration to ethene and, if and when the economics of alcohol manufacture justify its use as a biofuel, the polyolefins will again become biopolymers. So far as resource depletion is concerned, if fossil carbon resources were used only for the manufacture of polymers and not for energy production, the former would last for approximately 300 years based on present estimates. By that time, polyolefins will in any case probably be manufactured from renewable resources anyway for purely economic reasons. At... 

Renewable carbon resources is a misnomer the earth s carbon is in a perpetual state of flux. Carbon is not consumed such that it is no longer available in any form. Reversible and irreversible chemical reactions occur in such a manner that the carbon cycle makes all forms of carbon, including fossil resources, renewable. It is simply a matter of time that makes one carbon from more renewable than another. If it is presumed that replacement does in fact occur, natural processes eventually will replenish depleted petroleum or natural gas deposits in several million years. Eixed carbon-containing materials that renew themselves often enough to make them continuously available in large quantities are needed to maintain and supplement energy suppHes biomass is a principal source of such carbon. 

The percentage of energy demand that could be satisfied by particular nonfossil energy resources can be estimated by examination of the potential amounts of energy and biofuels that can be produced from renewable carbon resources and comparison of these amounts with fossil fuel demands. 

The other important issue is the future of fossil energy resources. As with carbon dioxide emissions, future predictions are highly uncertain. They relate to many economic factors. For instance, an increase in oil price makes oil exploitable that previously was uneconomic. Figure 1.3 shows the results of different prognoses. 

The other option is to capture the C02 and to store it. The amounts of C02 are huge if we continue to use the fossil fuel resource base. It is estimated to be over 6.000 gigatonnes of carbon (GtC) [1], The most attractive opportunity for this is geological (Fig. 1.7). 

The present world energy supply system is facing three basic problems (1) limitation of fossil fuel resources, (2) climate change by carbon dioxide emission, and (3) insecurity by nuclear weapon competence and radioactive materials. The strategic goal therefore should be to transition to unlimited resources, use zero-emission fuels and accept no options for abuse. 

The present resources of drinking water and fossil carbon components are already seen as limited. Careful use and development of alternatives is now being pursued. Process intensification has the potential of requiring less energy and thereby requiring less fossil carbon as fuel. 

Annual Increase in Fossil Fuel C02 Emissions Recoverable Conventional Fossil Fuel Resources Total Carbon in the Atmosphere (1982)... 

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