Method of roasting biomass and control method thereof

The process of heat treatment of lignocellulosic biomass at maximum 300[deg] C under controlled atmosphere in the absence of oxygen, comprises mixing the biomass in a reactor through a hot gas flow, primarily drying the resulting biomass, and roasting the dried biomass (5), where biomass undergoes o...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: LEBOUTTE, DIDIER
Format: Patent
Sprache:eng ; fre ; ger
Schlagworte:
Online-Zugang:Volltext bestellen
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The process of heat treatment of lignocellulosic biomass at maximum 300[deg] C under controlled atmosphere in the absence of oxygen, comprises mixing the biomass in a reactor through a hot gas flow, primarily drying the resulting biomass, and roasting the dried biomass (5), where biomass undergoes one or more exothermic transformation reactions. The reactor is provided with a unit for conveying and controlling the forwarding speed v of the biomass through the reactor, a heating unit with gas flow, a unit for collecting steam and gas, and a unit for measuring the pressure in the reactor. The process of heat treatment of lignocellulosic biomass at maximum 300[deg] C under controlled atmosphere in the absence of oxygen, comprises mixing the biomass in a reactor through a hot gas flow, primarily drying the resulting biomass, and roasting the dried biomass, where biomass undergoes one or more exothermic transformation reactions. The reactor is provided with a unit for conveying and controlling the forwarding speed v of the biomass through the reactor, a heating unit with gas flow, a unit for collecting steam and gas, a unit for measuring the pressure in the reactor and the pressure of collected steam and gas, and a unit for measuring and controlling the temperature in the reactor. The forwarding speed v and temperature T of heating gas is adjusted according to recorded temperature to ensure: a separation in the time of steam emissions obtained from the drying of gas and pyrolysis gas obtained from the roasting; and a homogeneous and constant roasting at the end of the process. The roasting takes place in an accurate and reproducible interval at a place of the reactor on the forwarding path of the biomass. The reactor is a rotating furnace, a screw furnace or a multiple hearth furnace comprising a series of N 0floors (1) or circular baking plates (2) laid above one another in a steel envelope (3) lined with insulation, a vertical rotating shaft of rotating speed (omega ) laid along the furnace axis bearing arms (4) equipped with back support for mixing the load and moving through holes through each floor. The biomass is loaded at floor top and moving downwards to form a sturdy bed on each hearth and is heated by a hot gas flow to carry the hearth at a temperature for forced drying and roasting the biomass. The speed of rotation of the shaft and the temperature T of heating gas is controlled during complete roasting of the biomass at the floor N. The complete roa