Fuel properties pyrolysis liquids

The quality of the product is of primary importance in developing a recycling technology converting plastics into fuels by pyrolysis. Today the characterization of a liquid fuel from any sources is obviously based on the qualification methods and standards of fuels from mineral oil. The properties of the pyrolysis-derived fuels from plastics are expected to be similar to conventional fuels (energy content, viscosity, density, octane and cetane number, flash-point, etc.). However, in addition to the familiar ranking values it is necessary to know more about the chemical composition of the plastic pyrolysis oil, because of the peculiarities as follows ... 

TABLE 8.11 Typical Properties of No. 6 Fuel Oil and Liquid Fuel from Flash Pyrolysis of Refuse-Derived Fuel ... 

A successful introduction of a new liquid fuel on the energy market will be very difficult because of the low quality of the present pyrolysis liquid. The adverse properties of pyrolysis liquids as fuel are well known [1, 2, 3, 4, 5]. Work is being carried out especially in Europe to improve its fuel quality. 

The relationships among hydroconversion of the coal liquids, sulfur distribution, and other important fuel properties still need to be evaluated. They are part of the S W-Gulf development program now under study. This paper summarizes some of the preliminary investigations carried out as a prelude to the development program. Data on reactions by which aromatic molecules are converted to gas are reviewed and correlated consideration is also given to the formation of aromatic molecules during pyrolysis of hydrocarbons. 

Oasmaa, A. c Peacocke, G.V.C. (2010) VTT. Technical Research Centre of Finland, Espoo, Finland. Properties and fuel use of biomass derived fast pyrolysis liquids, vol. 731. VTT, Publication. 

Oasmaa A. Fuel oil properties of wood-based pyrolysis liquids [Doctoral thesis]. Jyvaskyla, Finland University ofjyvaskyla. Laboratory of Apphed Chemistry. 2001. 46 p. 

Table 17. Properties and Analysis of Liquid Fuel and No. 6 Fuel Oil Liquid fuel produced by flash pyrolysis using char recycle (Fig. 10).

Investigators have used the words carbon and soot to describe a wide variety of carbonaceous solid materials, many of which contain appreciable amounts of hydrogen as well as other elements and compounds that may have been present in the original hydrocarbon fuel. The properties of the solids change markedly with the conditions of formation and, indeed, several quite well-defined varieties of solid carbon may be distinguished. One of the most obvious and important differences depends on how the carbon is formed carbon may be formed by a homogeneous vapor-phase reaction it may be deposited on a solid surface that is present in or near the reaction zone or it may be generated by a liquid-phase pyrolysis. 

The liquids require a hydrorefining step to stabilize their reactive properties, to reduce the asphaltenes and preasphaltenes, to reduce sulfur, nitrogen, and oxygen, and to make the liquids more distillable. The extent of hydrorefining depends on the end use of liquids—fuel oil or chemical feedstocks. The objective of this work is to evaluate the hydrorefining processibility of ORC flash pyrolysis coal tar as a part of the tar characterization task. Results of the initial phase of catalyst screening tests are reported in this chapter. 

Bio-oil from rapid pyrolysis is usually a dark brown, free-flowing liquid having a distinctive smoky odor. It has significantly different physical and chemical properties compared to the liquid from slow pyrolysis processes, which is more like a tar. Bio-oils are multicomponent mixtures comprised of different size molecules derived primarily from depolymerization and fragmentation reactions of the three key biomass building blocks cellulose, hemicellulose, and lignin. Therefore, the elemental composition of biooil resembles that of biomass rather than that of petroleum oils. Basic properties of biooils are shown in Table 33.7. More detail on fuel-related characteristics is provided in the literature.571... 

Boucher, M. E., Chaala, A., and Roy, C., Bio-oils obtained by vacuum pyrolysis of softwood bark as a liquid fuel for gas turbines. Part I Properties of bio-oil and its blends with methanol and a pyrolytic aqueous phase. 

This book covers thermal and catalytic pyrolysis processes that produce liquid fuels (or other useful chemicals) from waste plastics. The book provides a comprehensive overview of the main commercial plastics pyrolysis processes, the types of plastics that can be processed, the properties of the respective fuels produced and the key variables influencing the pyrolysis of plastics such as temperature, residence time, pressure and catalyst types. 

Pyrolysis of biomass is a thermochemical conversion technology of solid biomass into a liquid ( pyrolysis oil , bio-oil ). This liquid can be used as a fuel with properties comparable to (crude) mineral oils. The pyrolysis process itself is not subject to this paper, the technology is described in (6), where there is also given a equation for calculating the cost of the pyrolysis oil depending on plant size and feedstock price. 

Criteria for evaluating the suitability of biomass for a pyrolysis conversion process to obtain solid, liquid and gaseous fuels are developed based on the properties of the pyrolysis products. 

Moses C., (1994) "Fuel-Specification Considerations for Biomass Liquids". Proceedings Biomass Pyrolysis Oil Properties and Combustion Meetings T.A. Milne, ed., National Renewable Energy Laboratory. Golden, CO, NREL-CP-430-7215, pp. 362-282. 

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