Patent ID: 8703021

Claim:
A method of operating a slagging gasifier using a carbon feedstock and a CaO additive comprising: maintaining the slagging gasifier at a temperature of from about 1200° C. to about 2000° C., and a pressure of from about 300 psi to about 1000 psi, and an oxygen partial pressure of from about 10 −6 to about 10 −11 atmospheres; injecting a carbon feedstock into the gasifier at a feedstock injection rate, where the carbon feedstock is comprised of ash forming species, and where the ash forming species are comprised of less than about 25 wt. % SiO 2 , greater than about 20 wt. % V 2 O 5 , and less than about 20 wt. % CaO; injecting a CaO additive into the gasifier at an additive injection rate, where the CaO additive is comprised of CaO, thereby injecting a quantity of CaO and thereby generating a combined chemical composition in the gasifier, where the combined chemical composition consists of the ash forming species and the quantity of CaO; and establishing the feedstock injection rate and the additive injection rate such that the combined chemical composition is comprised of less than about 25 wt. % SiO 2 , greater than about 20 wt. % V 2 O 5 , and greater than about 20 wt. % CaO.