MDEA absorber flash gas
MDEA absorber flash gas
(OP)
We have an MDEA absorber to remove CO2/H2S in a natural gas stream. The MDEA co-absorbs a small amount of hydrocarbons in the absorber that is mostly flashed off from the rich solvent in the flash column. The normal flash gas from the flash column is, say, 1000 Nm3/h, based on a natural gas feed flowrate of 1000 kNm3/h.
The question if is natural gas feed stream is reduced to zero, does the flash gas flowrate stay about the same (1000 Nm3/h), assuming the lean solvent rate to the absorber stays the same? According to our process licensor, the flash gas rate should stay about the same (ie. the lean solvent will constinue to abosrb the same amount of hydrocarbons from the feed gas). However, I have my doubts as I would expect the mass transfer rate to decrease substantially if the feed gas rate is reduced to zero.
The question if is natural gas feed stream is reduced to zero, does the flash gas flowrate stay about the same (1000 Nm3/h), assuming the lean solvent rate to the absorber stays the same? According to our process licensor, the flash gas rate should stay about the same (ie. the lean solvent will constinue to abosrb the same amount of hydrocarbons from the feed gas). However, I have my doubts as I would expect the mass transfer rate to decrease substantially if the feed gas rate is reduced to zero.





RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
RE: MDEA absorber flash gas
2) After the feed gas stop longer than its retention time , the mass transfer will change ( in flow can not equal to out flow) , then your understanding is correct.
3) Normally eventhough thae gas stop but lean amine still doing absorbtion since their still has gas in the column, but acid gas H2S/CO@ already reduce but metahne or orther gas can co-absorb and produce its off gas, the the rate/composition will change as your understanding.