| 摘要 |
<p>1294460 Mg(OH), recovery COMBUSTION ENG Inc 29 Dec 1969 [31 Dec 1968] 63127/69 Heading C1A Mg(OH) 2 is recovered from an MgSO 4 containing sludge produced (see Specification 1,178,109) by reaction of combustion gases containing SO 2 with MgO, followed by scrubbing by introducing a soluble calcium salt to precipitate CaSO 4 , separating at least part of the magnesium salt solution produced and reacting it with Ca(OH) 2 to precipitate Mg(OH) 2 and form a solution of soluble calcium salt which may be used in the first stage of the process. The preferred calcium salt is CaCl 2 . Any MgSO 3 in the initial sludge may be oxidized to MgSO 4 before carrying out the extraction. The resulting Mg(OH) 2 may be calcined to MgO. Addition of the Ca salt and/or the oxidizing agent may take place in the scrubber. Reference has been directed by the Comptroller to Specification 1,178,109.</p> |
