| 摘要 |
<p>Anhydrous Na2CO3 of high density is prepd. by thermal decomposition of NaHCO3 or a NaHCO3-contg. cpd., by adding the NaHCO3 to a reactor contg. a slurry of Na2CO3 which is circulated over a heat eschanger and held at a temp. of over 135 ddg.C, and the anhydrous Na2CO3 formed in suspension is removed and separated from the mother liquor. the reactor and the heat ex changer are situated w.r.t. each other such that the static height H of the aq. slurry above the heat exchanger satisfied relationship (I) in which t=wall temp. of the heat exchanger, deg.C; s=the content of any salts present besides carbonate and bicarbonate, calculated as NaCl in wt.%; p=the vapour press. developed by the system in bar; and d=the density of the aq. slurry in g/cm3.</p> |
