Mercury & Arsenic Removal
Market prices of crudes or condensates from arsenic and mercury contaminated reservoirs will remain in the near future much lower than those of uncontaminated feedstocks, justifying their increasing utilization.
During the past 20 years the utilization of a more diverse feedstock supply containing metal impurities has led to operating problems such as corrosion of aluminium alloys in steam crackers cold boxes and serious increases in catalyst poisoning caused by mercury and arsenic. In addition, the impact of mercury, arsenic and lead on the environment and the health of personnel will become a key issue in the coming years and focus will be made on means to remove them.
The RAM™ process provides the ultimate solution, transforming contaminated liquid feedstocks value from negative to positive. The financial leverage afforded by this process is considerable since a large part of petrochemical plant or refinery profitability results from the cost of the feedstock alone.
Axens technologies for removing arsenic and mercury from liquid feedstocks rely on expertise cumulated over years that give Axens the status of a major market player in this field.
Depending on the diverse Hg and As species present in naphtha, crude oil or condensate cuts, Axens can offer several types of simple and robust processes to address the market demand:
- The RAM II process is ideally suited to simultaneous removal of arsenic, mercury and lead from contaminated liquid feedstock upstream of aromatics plants or steam-cracking units. RAM is designed to remove organic and ionic mercury which may represent up to 50% of the reported mercury in liquid streams when other adsorbent technologies only remove elemental mercury. Typical results are excellent with less than 3 ppb of each contaminant in the process effluent (the threshold limit for analysis) with estimated values of 1 ppb.
- The RAM III process is a cheap variant of the RAM II process that can be profitably integrated to any hydroprocessing technology and is particularly well suited to reforming and isomerization pretreatment units.
The RAM technology is industrially proven at very low mercury and arsenic content in the process effluent (less than 1 ppb of each contaminant) complying with the required specifications for processing of contaminated feedstock in conventional refinery or steam cracking plants.