Effective oil/water separation continues to be a majorrnchallenge in heavy oil (HO) production operations and oftenrninvolves high capital costs (large, heated vessels) and highrnoperation costs (heat, fouling, upsets, chemicals). Applicationrnof new electrostatic dehydration technologies has the potentialrnto have a major impact in reducing these costs. A systematicrnevaluation of four electrostatic dehydration technologies wasrnperformed using lab, bench scale, and pilot scale (40 gallons)rntesting. Four heavy oils ranging from 8 to 21 API were used.rnPerformance criteria measured were effective emulsionrnseparation rate (vessel throughput), separated oil and brinernquality, water droplet size distribution for inlet and outletrnemulsions, and comparison with field data (as available) forrnolder electrostatic technologies. Traditional bottle tests werernperformed for reference. A 2 to 4 fold increase in emulsionrntreating rate was observed for some of the heavy oils using thernnewer electrostatic technologies relative to the traditionalrnAlternating Current (AC) method with the same output qualityrnof crude and brine. Relative cost data per barrel of emulsionrnprocessed were developed from system cost estimates andrnthroughput data developed in the pilot tests. Treatment withrnacid to bring the separated brine into a 6 to 6.5 pH range had arnvery beneficial effect on the oil/water separation for some ofrnthe heavy oils with high TAN.
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