British Gas/Lurgi (BGL) Slagging Gasifier
The BGL slagging gasifier is an extension of the Lurgi pressure gasification technology developed by British Gas and Lurgi with the ash discharge designed for slagging conditions. Initial work took …
Twin Fluid-Bed Steam Gasification The SilvaGas Process
This two-stage atmospheric biomass gasification process was developed by Battelle, and the first commercial demonstration unit with a feed capacity of 200t/d was built in Burlington, Vermont. Commercialization of the …
Agglomerating Fluid-Bed Processes
The idea behind agglomerating fluid-bed processes is to have a localized area of higher temperature where the ash reaches its softening point and can begin to fuse. The purpose of …
Marine Cropping
A possible solution to large-scale biomass production in an environmentally acceptable manner could be plantations of salt-water organisms in desert areas, Table 4-18 Typical Properties of Bio-Oil Property Typical Values …
The EAGLE Gasifier
The EAGLE Gasifier is an oxygen-blown two-stage dry-feed reactor currently under development by the Electric Power Development Company in Japan. A 150 t/d pilot plant has been built and commenced …
Process Performance
A comparison between the performance of the Lurgi dry ash and the BGL gasifier is given in Table 5-5. The much lower steam and somewhat lower oxygen consumption of the …
Pyrolysis Processes
As discussed in Section 4.3, the logistics of biomass collection will in general limit biomass gasification facilities to a maximum of 30-40 MWth. In order to overcome this limitation in …
Development Potential
Many fluid-bed gasification processes have been and are being developed, but none of them incorporate the use of a heat carrier (sand and/or ash and/or char) in such a way …
WASTES
“Waste” as a gasification feedstock covers a wide range of materials, both solid and liquid. Some materials, which we include in this section, could as easily have been included under …
OIL GASIFICATION AND PARTIAL OXIDATION OF NATURAL GAS
Technologies for the gasification of liquid and gaseous feeds were developed at the end of the 1940s by Texaco and in the early 1950s by Shell. These two technologies have …
Ruhr 100
Another development of the Lurgi dry-bottom gasifier was the high-pressure Ruhr 100 gasifier which was designed for operation at 100 bar. Apart from its high - pressure capability, the reactor …
Other Liquid Feedstocks
Orimulsion. Orimulsion is the trade name for an emulsified bitumen-water mixture produced from the bitumen fields in the Orinoco belt of Venezuela. Orimulsion consists of about 70% bitumen and 30% …
ENTRAINED-FLOW GASIFIERS
As discussed at the beginning of this chapter, the principal advantages of using entrained-flow are the ability to handle practically any coal as feedstock and to produce a clean, tar-free …
Solid Waste
One of the difficulties with refuse is the variability of its chemical composition. For a study comparing various refuse incineration and gasification processes, the State Environmental Office of Nordrhein-Westfalen developed …
The Texaco Gasification Process
The Texaco Gasification Process was developed in the late 1940s. Early research efforts focused on producing syngas from natural gas to produce liquid hydrocarbons via Fischer-Tropsch technology. The first commercial-scale …
FLUID-BED GASIFIERS
The history and development of coal gasification and fluid-bed technology have been intimately linked since the development of the Winkler process in the early 1920s. Winkler’s process operated in a …
Natural Gas
Compared with the variety of aspects needing evaluation when dealing with liquid feeds, natural gas is relatively simple, and the principle issues to be considered are more of an economic …
General Considerations
Dry-Coal Feed Gasifiers As discussed in Chapter 2, dry-coal feed gasifiers have the advantage over coal - water slurry feed gasifiers in that they can operate with almost the minimum …
Syngas and Hydrogen Applications
For synthesis-gas application the situation is somewhat different. In this case the moles of H2+CO per unit feedstock have to be optimized. The effect of the operating conditions on this …
Gasification
Ultimate Analysis
For the ultimate analysis the percentages of carbon, hydrogen, oxygen, sulfur, and nitrogen are determined. In the past, oxygen was sometimes reported as “by difference.” If at all possible this …
Feedstocks
Feedstocks for gasification may vary from natural gas to heavy oil residues and coal. Furthermore, waste streams and biomass may be used. In order to carry out proper calculations it …
The Kinetics of Gasification and Reactor Theory
The kinetics of gasification is as yet not as developed as is its thermodynamics. Homogeneous reactions occurring, for example, in the gas phase can often be described by a simple …
COMPANION WEBSITE
As an accompaniment to this book, we have built a website (www. gasification. higman. de), which includes a number of computer programs arising out of the work involved in preparing …
Other Minerals in Coal
Beyond the elements described above, which are provided with every ultimate analysis of coal, it will be found that a substantial part of the periodic table can be shown to …
Moderator
The most common moderator used in gasification processes is steam. The steam must have a minimum temperature corresponding to that of saturated steam at the pressure prevailing in the gasifier, …
Devolatilization
The first step, heating up of the coal particles, is in one sense the simplest part of the process. Nonetheless, the speed at which it takes place has an influence …
Introduction
The manufacture of combustible gases from solid fuels is an ancient art but by no means a forgotten one. In its widest sense the term gasification covers the conversion of …
Other Properties Heating Value
The heating value is obtained by combustion of the sample in a calorimeter. If not available, the heating value can be calculated with, for example, the Dulong formula (Perry and …
Equations
Forgetting for the moment the presence of other compounds and elements such as sulfur, nitrogen, argon, ash, and so on, the following equations will apply in virtually all gasification processes. …
Volatiles Combustion
The devolatilization of coal produces a variety of species, including tars, hydrocarbon liquids, and gases, including methane, CO, C02, H2, H20, HCN, and so forth. (Smoot and Smith 1985). This …
HISTORICAL DEVELOPMENT OF GASIFICATION
The development of human history is closely related to fire and therefore also to fuels. This relationship between humankind, fire, and earth was already documented in the myth of Prometheus, …
Caking and Swelling Properties
Another important property of a coal is the swelling index. The swelling index is determined by heating a defined sample of coal for a specified time and temperature, and comparing …
Variables
Again ignoring sulfur, nitrogen, and others initially, it is necessary to define eight variables for the heterogeneous case and seven for the homogeneous one to provide a mathematically soluble problem. …
Char Gasification
The slowest reactions in gasification, and therefore those that govern the overall conversion rate, are the heterogeneous reactions with carbon, namely the water gas, Boudouard, and hydrogenation reactions already discussed …
