Process for purifying raw gas from the gasification of solid fuels

Claim 1

In the production of a purified hydrogen and carbon monoxide-containing gas comprising the steps of treating a solid fuel at a pressure of 4 to 150 bars with a gasifying agent containing water vapor and oxygen to produce a raw gas containing hydrocarbons, sulfur compounds and dust in the amount of about 2 to 12 grams per standard cubic meter of dry gas and which is at a temperature of 400° to 700° C, the improvement which comprises spraying into the raw gas in a first scrubbing stage under a pressure of 4 to 150 bars highly dispersed scrubbing water at a temperature of 160° to 300° C thereby saturating the gas with water vapor, the scrubbing water containing less than 200 milligrams of solids per liter, 0.5 to 6 liters of scrubbing water being sprayed in per standard cubic meter of gas whereby the gas is cooled to a temperature of 0° to 20° C above the scrubbing water temperature, said first scrubbing stage being a cyclone scrubbing zone to which the raw gas is admitted tangentially to the inside surface of said zone, passing the gas into a second scrubbing stage at a pressure of 4 to 150 bars, spraying into said second stage in radial direction salt-free water with a temperature of 160° to 300° C containing less than 200 milligrams of solids in an amount of 0.1 to 0.3 liter per standard cubic meter of dry gas, removing from the second stage purified gas saturated with water vapor and containing 1 to 6 milligrams of solids per standard cubic meter, desulfurizing the gas after at least one of the first and second scrubbing stages and feeding the scrubbed and desulfurized gas into a power plant process.