<AREA SHAPE=RECT COORDS="6,87,24,105" HREF="!Separating raw natural gas from crude oil obtained from a well is the first step in recovering sulfur. After the gas has been separated, it is transferred to a cleaning plant. There, a complex purification process removes hydrogen sulfide from the gas.">
<AREA SHAPE=RECT COORDS="6,245,24,262" HREF="!Conversion of the hydrogen sulfide to sulfur occurs in a Claus kiln. Air and water are added to this combustion chamber, and the hydrogen sulfide is heated to form a mixture of sulfurous gases and water vapor. Much of the sulfur condenses to liquid form. The remaining waste gas is removed and incinerated.">
More than half of the sulfur used today is recovered from sulfur compounds in oil and natural gas through <I>Claus conversion.</I> This diagram shows the basic steps involved in this process.<NP>
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World Book diagram by Zorica Dabich</P>
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