Page 677 - Radiation Safety
P. 677
OIL AND GAS INDUSTRY
• Reservoir rock contains small amounts of
natural uranium and thorium and daughters.
One daughter, radium, is water soluble -
dissolves in the reservoir water.
• Reservoir water is rich in calcium, barium
and strontium ions. Injection water is rich in
sulphate ions. When they mix, precipitation
of calcium, barium and strontium sulphate
occurs.
• Pressure and temperature drops also
promote precipitation.
• This causes a layer of scale to form inside
production tubing and process vessels.
22
