Extraction of sulphur by Frasch Method
sulphur is extracted by HERMAN FRASCH METHOD
PRINCIPLE
The basic principle of Frasch Method is that sulphur is melted underground and pumped up to the surface of the earth.
DETAILS OF PROCESS
SYSTEM CONFIGURATION
A bore is made to the underground deposits of sulphur and three concentric pipes are sunk into the bore.
OUTER PIPE
The outer most pipe has diameter of 20 cm is sunk upto the deposits .This pipe is an inlet for super heated water.
MIDDLE PIPE
The 2nd pipe of 10 cm diameter is held a little above the surface of sulphur deposits. This pipe is outlet for molten sulphur.
INNER PIPE
The inner most pipe is used to blow hot compressed air into the deposits of sulphur.

 
METHOD
Superheated steam at 170oC under 16 atmp is pumped down the outer most pipe . Since melting point of sulphur is 113oC , it is melted and collects at the bottom. Hot compressed air is blown down the inner most pipe to produce foam of molten sulphur . This foam rises through the annular space between the inner most pipe and the next