Development of the Oxygen Donor Gasifier for Conversion of Wood to Synthesis Gas for Eventual Production of Methanol

Summary

The Oxygen Donor Gasifier consists of two reactors containing fluidised beds which are exchanged between the reactors in a continuous flow.

The wood is fed into the Gasifier which contains calcium sulphate and calcium oxide in its bed. The calcium sulphate is reduced to calcium sulphide providing the oxygen to gasify the wood. The gases leaving the Gasifier are cleaned in cyclones, cooled in a waste heat boiler, and finally cooled and cleaned in a direct water spray. Part of this gas is used to fluidise the Gasifier, the remainder being the product Synthesis Gas.

The stone from the Gasifier is transferred to the Oxidiser where the calcium sulphide is oxidised by air back to the sulphate. The hot flue gases leaving the Oxidiser are cleaned, and used to preheat the incoming air, the remainder of the heat in the flue gases can be used to predry the wood feed.