LPG

Calor gas, Calor propane The trade name for a liquified petroleum gas (LPG) sold in cylinders for domestic and industrial healing. Calor gas is the name used for commercial butane while commercial propane is sold as Calor propane. 

Typical chromatogram obtained with a sebaconitrile column (mixture ofrefe rence containing LPG components). 

As their name implies, these products are used essentially for jet aircraft they can also be used in stationary turbines, which are themselves adaptable to a large variety of fuels such as natural gas, LPG, diesel fuel, and heating oil. 

Utilization of LPG as motor fuel represents only a tiny fraction of the market, on the order of 30,000 t/an in France out of a total 3,000,000 t that is, about 1%. Globally, the fraction of LPG used in the transportation industry is on the order of 5% the other applications are essentially petrochemicals (25%) and the heating fuel sectors (70%). However noticeable openings in the LPG-fuel markets in some countries such as Japan (1.8 Mt), the United States (1.3 Mt), the Netherlands (0.9 Mt), Italy (0.8 Mt) and in certain regions (Latin America, Africa, and the Far East) have been observed for specialized vehicles such as taxis. 

LPG, stored as a liquid at its saturation pressure, is vaporized and introduced as vapor in conventional spark ignition motors. These motors are not modified with the exception of their feed system. Moreover, in the majority of cases, dual fuel capabilities have been adapted, that is, the vehicle can use either LPG or liquid fuel. 

The potential advantages of LPG concern essentially the environmental aspects. LPG s are simple mixtures of 3- and 4-carbon-atom hydrocarbons with few contaminants (very low sulfur content). LPG s contain no noxious additives such as lead and their exhaust emissions have little or no toxicity because aromatics are absent. This type of fuel also benefits often enough from a lower taxation. In spite of that, the use of LPG motor fuel remains static in France, if not on a slightly downward trend. There are several reasons for this situation little interest from automobile manufacturers, reluctance on the part of automobile customers, competition in the refining industry for other uses of and fractions, (alkylation, etherification, direct addition into the gasoline pool). However, in 1993 this subject seems to have received more interest (Hublin et al., 1993). 

Finally, there are some limits regarding LPG fuels butadiene content (0.5 wt. % maximum, ISO 7941), the absence of hydrogen sulfide (ISO 8819) and copper strip corrosion (class 1, ISO 6251) which are not usually problems for the refiner. 

This category comprises conventional LPG (commercial propane and butane), home-heating oil and heavy fuels. All these materials are used to produce thermal energy in equipment whose size varies widely from small heaters or gas stoves to refinery furnaces. Without describing the requirements in detail for each combustion system, we will give the main specifications for each of the different petroleum fuels. 

LPG is divided into two types of products commercial propane and commercial butane, each stored as liquid at ambient temperature and corresponding vapor pressure. 

Calculational methods. Associating the analysis, the knowledge of the property-structure relationships, and the calculation methods has made possible the replacement of costly and arduous test methods by quicker tests whose results are linked by calculations to the characteristic under study. Some examples are the cetane number, in some cases, the octane number, or the characteristics of LPG (refer to Chapter 3). 

Product Characteristics Commercial butane Commercial propane LPG motor fuel (from NF EN 589) (see AFNOR document M 40-003)... 

In addition to reformate, reforming provides hydrogen, an important byproduct, and a small quantity of gas and LPG. 

Compound Feedstock, weight % Alkylate, weight % LPG, weight % Losses, weight %... 

Properly speaking, steam cracking is not a refining process. A key petrochemical process, it has the purpose of producing ethylene, propylene, butadiene, butenes and aromatics (BTX) mainly from light fractions of crude oil (LPG, naphthas), but also from heavy fractions hydrotreated or not (paraffinic vacuum distillates, residue from hydrocracking HOC). 

Feedstocks are natural gas, refinery fuel gas, LPG and paraffinic naphthas. After elimination of CO2, the last traces of contaminants are converted to methane (methanation) or eliminated by adsorption on molecular sieves (PSA process). 

The hydrocracking process is characterized by a very low gas production and a low LPG yield especially when operated for maximum distillates. Byproducts in this operating mode are ... 

Fractions treated by this process are light products from the primary distillation LPG to Kerosene, or light products from thermal and catalytic cracking (visbreaking, coking, FCC). 

Vapor pressure of LPG NFM 41-010 ISO 4256 ASTM D 1267 Pressure in a sample bomb held at predetermined temperature... 

Volatility of LPG NFM 41-012 ISO/DIS 6620 ASTM D 1837 Measurement of residue temperature after 95% evaporation... 

The products could be classified as a function of various criteria physical properties (in particular, volatility), the way they are created (primary distillation or conversion). Nevertheless, the classification most relevant to this discussion is linked to the end product use LPG, premium gasoline, kerosene and diesel oil, medium and heavy fuels, specialty products like solvents, lubricants, and asphalts. Indeed, the product specifications are generally related to the end use. Traditionally, they have to do with specific properties octane number for premium gasoline, cetane number for diesel oil as well as overall physical properties such as density, distillation curves and viscosity. 

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