Horizontally-Oriented Gasifier with Lateral Transfer System
A method and apparatus is described for the efficient conversion of carbonaceous feedstock including municipal solid waste into a product gas through gasification. More specifically, a horizontally-oriented gasifier having one or more lateral transfer system for moving material through the gasifier is provided thereby allowing for the horizontal expansion of the gasification process such that there is sequential promotion of feedstock drying, volatization and char-to-ash conversions.
1 - 9 . (canceled)
10 . A method for converting a carbonaceous feedstock to an off-gas and ash, comprising the steps of:
a) establishing three regional temperature zones in a gasifier; wherein a first zone has a temperature which promotes drying, a second zone has a temperature which promotes volatization and a third zone has a temperature which promotes char-to-ash conversion;
b) providing carbonaceous feedstock to the first zone and maintaining the carbonaceous feedstock at the first zone for a period of time to obtain a substantially dried reactant material;
c) passing the substantially dried reactant material to the second zone for a period of time such that volatile components of the substantially dried reactant material are volatilized to form off-gas; and
d) passing residual char from the second zone to the third zone for period of time such that the char is converted to additionally off-gas and ash.
11 . The method of claim 10 , wherein movement of reactant material through the gasifier is controlled based on pile height or pile profile.
12 . The method of claim 10 , comprising inputting process additives into the gasifier.
13 . The method of claim 10 , wherein the method is subject to feedback control.
14 . The method of claim 12 , wherein the method is subject to feedback control.
15 . The method of claim 10 , further comprising the step of converting the ash to slag.
16 . The method of claim 10 , wherein the gasifier is a horizontally oriented gasifier.
17 . The method of claim 10 , further comprising reformulating the off-gas.
18 . The method of claim 17 , wherein reformulating the off-gas comprises treating the off-gas with plasma heat.
19 . The method of claim 10 , further comprising treating the off-gas with a cyclonic oxidizer.
20 . The method of claim 10 , wherein the carbonaceous feedstock is municipal solid waste.
21 . The method of claim 12 , wherein the process additives are hot air and/or steam.