Water removal from anti-agglomerate LDHIs
View Patent ↗A method of controlling corrosion in a subsea pipeline is disclosed which includes supplying a low dose inhibitor stream (LDHI) comprised of a quaternary amine and drying with a desiccant.
1. A method for controlling corrosion in an umbilical comprising:
providing an first instance low dose hydrate inhibitor (LDHI) stream, the LDHI stream containing water;
determining a first maximum allowable water content of the LDHI stream;
determining that water content in the LDHI stream exceeds the first maximum allowable water content;
drying the LDHI stream based upon the water content in the LDHI stream exceeding the first maximum allowable water content, so as to form a dried LDHI stream; and
injecting the dried LDHI stream into the umbilical.
2. The method of claim 1 further comprising:
filtering the LDHI stream or the dried LDHI stream before injecting the LDHI stream or the dried LDHI stream into the umbilical.
3. The method of claim 1 further comprising before the injecting step but after the drying step:
monitoring the water content in the dried LDHI stream.
4. The method of claim 1 , further comprising:
determining a second maximum allowable water content of the LDHI stream; and
after drying the LDHI stream but before injecting the dried LDHI stream, determining that the water content in the dried LDHI stream exceeds the second maximum allowable water content.
5. The method of claim 4 , wherein the second maximum allowable water content is 0.5 volume % water.
6. The method of claim 1 wherein the step of drying the LDHI stream is performed by contacting the LDHI stream with an external desiccant.
7. The method of claim 6 , wherein the external desiccant comprises a desiccant selected from the group consisting of: clay, silica gel, a molecular sieve, calcium oxide, calcium sulfate, activated charcoal, calcium chloride, a metal salt, activated alumina, aerogel, benzophenone, calcium hydride, cobalt(II) chloride, copper(II) sulfate, lithium chloride, lithium hydride, lithium bromide, magnesium, magnesium sulfate, magnesium perchlorate, a sodium-potassium alloy, phosphorus pentoxide, potassium, potassium carbonate, sodium, sodium chlorate, sodium chloride, sodium hydroxide, sodium sulfate, sodium-benzophenone, sucrose, sulfuric acid, and any combination thereof.
8. The method of claim 7 , wherein the clay is a Mont-morillonite clay.
9. The method of claim 7 , wherein the molecular sieve is a synthetic zeolite.
10. The method of claim 1 , wherein the first maximum allowable water content is 0.9 volume % water.