Silica scale precipitation prevention method null from geothermal

摘要

PURPOSE: To prevent the formation of silca scales in the geothermal water transport pipe and underground permeable layer by efficiently producing dil. sulfuric acid from the geothermal noncondensable gas recovered along with geothermal water and adding the obtained dil. sulfuric acid to the geothermal water. ;CONSTITUTION: A noncondensable gas 1 having a low content of H₂S discharged from a geothermal power plant is pressurized by a blower 2 and supplied to an adsorption tower 4a to adsorb H₂S, and the remaining gaseous N₂ is discharged outside the system from a passage 7. Meanwhile, an adsorption tower 4b after adsorption is purged with gaseous N₂ by driving a vacuum pump 9, and the gaseous H₂S is reduced in volume, concentrated and recovered. The gaseous H₂S is burned in a combustor 13 and converted to SO₂, the SO₂ is cooled, supplied to a catalyst bed 18 and converted to SO₂, and the SO₂ is absorbed in water in a water absorption tower 20 and recovered as dil. sulfuric acid. The dil. sulfuric acid is added to the geothermal water to prevent the formation of silica scales in a geothermal water transport pipe and the underground permeable layer 29.;COPYRIGHT: (C)1994,JPO