Pressure calamities

He removes a pressure gauge on one tank, attaches a water hose to the opening and turns on the faucet. Two hours after he steals away, a calamity he never foresaw begins unfolding. The tank rumbles. Vapors pass into a vent tower. A large cloud of poison gas drifts out into the night. 

Over the last decade especially, calamities of weather and war have pressured petroleum and natural gas prices upward, and this has periodically shifted the cost of PO feedstocks in radical ways. Minimizing the amount of PO in a product is one way to soften the blow of major raw material cost changes [1-2]. 

The analysis of the oil has been reviewed by Lawrence [37 2]. Extraction of aniseed with S.CO2 has been reported by Calame and Steiner [13]. At a pressure of 300 bar and 40°C for extraction and a subsequent fractionation at 75 bar and 40°C they obtained a yield of 7%. The spice used had a steam distillation yield of 2.1%. 

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