Chevron's Technology Marketing invites you to contact our New Business Development group to learn about licensing our MERCAWAY℠ process technology as well as MERCAWAY technical services provided to our licensees.
MERCAWAY process technology is a straightforward process for reducing mercury (Hg) content in crude oil and condensate using easily understood chemistry and well-proven unit operations.
There are four key steps in the MERCAWAY processing system as follows:
The Desanding Step is accomplished using a hydrocyclone to achieve removal of sand and other particulates. The Desanding Step reduces the filtration load and improves cycle length. Depending on the nature of the produced crude/condensate stream, this step may be omitted.
The Reaction Step is conducted by introducing a treat chemical bearing at least one Hg reactive sulfur (S). The treat chemical dosage required can be readily determined using laboratory test methods for the crude or condensate to be treated. The reaction takes place in a stirred reactor at modest temperature and pressure.
The key reaction is
Hg° + S donating compound → HgS
The Filtration Step uses a pressurized precoat filtration system with operating cycle expected to range from 12–48 hours depending on feed and other filtration variables. In the current application, diatomaceous earth (DE) is added first as a filter precoat and later a finer grain DE is added to the feed to achieve filtration to 0.7μ. DE addition rate is determined during the laboratory testing phase. Filtration has proven to provide 98% removal of HgS. The Hg containing filter cake is discharged at the end of every cycle for environmentally acceptable disposal.
The Polishing Step is conducted in a fixed absorbent bed for further reduction of Hg content of the crude. This step may be unnecessary if acceptable levels of Hg removal are achieved after the Filtration Step.