Fossil replacement

Triglyceride oils have declined since the 1980s and have been replaced by petroleum-derived products. However, as fossil fuels deplete the supply of petrochemicals, triglyceride-based oils are available as a renewable resource. 

Alternative feedstocks for petrochemicals have been the subject of much research and study over the past several decades, but have not yet become economically attractive. Chemical producers are expected to continue to use fossil fuels for energy and feedstock needs for the next 75 years. The most promising sources which have received the most attention include coal, tar sands, oil shale, and biomass. Near-term advances ia coal-gasification technology offer the greatest potential to replace oil- and gas-based feedstocks ia selected appHcations (10) (see Feedstocks, coal chemicals). 

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. 

Percent of cobs and stalks collected and used as fuel within system to replace fossil fuel inputs. 

The Fossil Power Plants of the 1990s and into the early part of the new millennium will be the Combined Cycle Power Plants, with the gas turbine as being the centerpiece of the plant. It is estimated that between 1997-2006 there will be an addition of 147.7 GW of power. These plants have replaced the large Steam Turbine Plants, which were the main fossil power plants through the 1980s. The Combined Cycle Power Plant is not new in concept, since some have been in operation since the midl950s. These plants came into their own with the new high capacity and efficiency gas turbines. 

A secondary benefit is that efficiency gains in fossil fuel generation also reduce all types of harmful emissions, even carbon dioxide—the greenhouse gas suspected by many as a major culprit of climate change. A 45 percent efficient plant releases approximately 40 percent less COn per megawatt-hours of electricity produced than a 25 percent efficient plant that it might be replacing. 

Large-scale crude oil exploitation began in the late nineteenth century. Internal combustion engines, which make use of the heat and kinetic energy of controlled explosions in a combustion chamber, were developed at approximately the same time. The pioneers in this field were Nikolaus Otto and Gottleib Daimler. These devices were rapidly adapted to military purposes. Small internal-combustion motors were used to drive dynamos to provide electric power to fortifications in Europe and the United States before the outbreak of World War I. Several armies experimented vith automobile transportation before 1914. The growing demand for fossil fuels in the early decades of the twentieth centuiy was exacerbated by the modernizing armies that slowly introduced mechanization into their orders of battle. The traditional companions of the soldier, the horse and mule, were slowly replaced by the armored car and the truck in the early twentieth century. 

In the 1970s it was generally supposed that nuclear fission would replace fossil fuels (oil, natural gas, coal) as an energy source. That hasn t happened. The most evident reasons are ... 

Where replacement of pretreatment and purification equipment is required, RO is often the technology of choice to supplant softeners, dealkalizers, and demineralization units, whether the boiler is a 100 psig unit for HVAC, an aging 1,000 MW fossil-fuel power plant, or a 2,000+ MW supercritical supplying power and district heat. 

Our complex modern life style was made possible by the discovery and refining of fossil fuels, fuels that are the result of the decay of organic matter laid down millions of years ago. The natural gas that heats our homes, the gasoline that powers our automobiles, and the coal that provides much of our electrical power are fossil fuels. Vast reserves of petroleum, the source of liquid hydrocarbon fuels such as gasoline and coal, exist in many areas of the world. However, although large, these reserves are limited, and we are using them up at a much faster rate than they can be replaced. 

As we moved away from natural and manual inputs to produce crops, other inputs of machinery, fertilizer, pesticides, herbicides and fuel, many of a chemical nature, commercial or cultural energy was used as a replacement. The commercial or cultural energy has come primarily from a fossil fuel base. The approximate amount of energy to provide for these inputs is given in Table I. 

Note MPW is Mixed Plastic Waste MSW ca is municipal solid waste and comparable material Typical capacities considered are 50 ktpa to 200 tpa Theoretical potential if most blast furnaces and cement kilns in the EU start to replace regular fossil resources by MPW ... 

Coal used in power stations has the potential to be partly replaced by fuels derived from pre-treated plastics and paper waste, reducing both dependency on fossil fuels and reliance on landfill. APME reports on a project in the Netherlands which it co-sponsored to develop a substitute fuel from plastics. The environmental assessment of the project compared the environmental impacts of coal substitution with other plastics recovery methods, including gasification in feedstock recycling and energy recovery from plastics waste in cement kilns. The study also compared coal substitution with the generation of power from burning biomass. 

Currently there is an urgent need to develop hydrogen storage materials for mobile and stationary appHcations. This trend is accelerated by the hydrogen fuel cell technology that could, within the next decades, replace fossil fuel resources such as oil and gas. 

A reaction A S bond breaking - bond forming (1365 kJ) + (- 1840 kJ) — -475 kJ The large negative A E for this reaction is one of the reasons why molecular hydrogen is a candidate to replace fossil fuels, as described in our chapter opener. 

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