Hot gas clean

The use of hot gas clean-up methods to remove the sulfur and particulates from the gasified fuel increases turbine performance by a few percentage points over the cold clean-up systems. Hot gas clean-up permits use of the sensible heat and enables retention of the carbon dioxide and water vapor in the... 

Squires, A. M., The City College Clean Fuels Institute Programs for (i) Gasification of Coal in High-Velocity Fluidized Beds (ii) Hot Gas Cleaning, Symp. Clean Fuels from Coal, I.G.T., Chicago (1975c)... 

Graham, R.G. and R. Bain, 1993. Biomass Gasification Hot Gas Clean-up. Report Submitted to IEA Biomass Gasification Working Group, Ensyn Technologies/NREL, 44 pp. 

Sulphur poisoning of nickel catalysts in catalytic hot gas cleaning conditions of biomass gasification... 

If the end use requires that the product gas remain at high temperature, at or slightly below the gasifier exit temperature, then some method of hot gas cleaning will be needed for tar elimination. Wet scrubbing is still an option, however, there will be a severe thermodynamic penalty from cooling and reheating the conditioned product gas, reduc-... 

The aim of this paper is to study the behavior of a earbonaceous material in PAH abatement in hot gas cleaning in real conditions, e.g. power stations where moisture and CO2 are present. Therefore, the Phe adsorption isotherms eontaining different steam and CO2 concentrations were obtained and fitted to different theoretical models. 

The DWSA installation can be divided into two main parts. The first part consists of an air preheater, fluidised bed reactor, solid fuel dosing vessel with on-line mass determination system and a hot gas cleaning section, containing a cyclone and a ceramic candle filter (Schumacher type). In the fluidised bed reactor the solid fuel is gasified with air to produce a low calorific value (LCV) gas that is cleaned of fly ash and unreacted solid carbonaceous material. Air and also additional nitrogen can be preheated and is introduced into the reactor by four nozzles just above the distributor plate. The reactor is electrically heated in order to maintain a constant temperature over bed as well as freeboard section. The solid fuel is fed into the bed section in the bottom part Just above the distributor by a screw feeder from beside. The hot gas cleaning section ensures a good gas-solid separation efficiency, with filter temperatures of about 500 C. 

For systems based on hot gas cleaning, the tars are only considered problematic if they condense during the transport from the gasifier to the end-user equipment, e.g. the gas turbine. 

Internal inspection of the turbine and combustors is carried out after every test run and we can now say that the hot gas clean-up is operating most satisfactory and no damage to the delicate parts of the turbine etc has been observed. 

Several cleaning techniques exist for the removal of these contaminants (1,2). These techniques can be subdivided into the three classes hot gas cleaning, dry scrubbing/removal techniques and wet scrubbing/removal techniques. Table 1 was used as a structure for the discussion in this workshop. On the basis of this table, the following discussion topics were chosen ... 

This topic is covered by a large 5FP EU project (NNE5 99 00923). This topic did not raise a discussion but is seen as an important field of R D in particular for the development of hot gas cleaning in biomass-IGCC. 

Develop the catalytic removal of NH3 which is important particularly in hot gas cleaning for IGCC application of fuel gases (activities are being performed in 5FP EU project) ... 

Ikenaga, N., Ohgaito, Y., Matsushima, H., and Suzuki, T. Preparation of zinc ferrite in the presence of carbon material and its application to hot-gas cleaning. Fuel, 2004, 83, 661. 

Sulfur Poisoning of Nickel-based Hot Gas Cleaning Catalysts in Synthetic Gasification Gas... 

In the hot gas clean-up system of a coal-burning fluidized bed power plant, acoustic agglomeration could be installed after the first cleaning cyclones and followed by a high efficiency cyclone. The power required to operate the acoustic agglomerator is about 0.02-0.5<7o of the power plant output. This means that for a 250 MW power plant several hundred kilowatts of acoustic power are needed. Compared with the acoustic power output of a four-engine jet aircraft... 

P. SimeU, Catalytic hot gas cleaning of gasification gas. Espoo 1997, VTT Publications 330 Technical Research Center of Finland Finland, 1997. 

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