Methods for refining brine in the ammonia-soda process?
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May I ask everyone: The raw material used in the ammonia-soda process at my workplace is underground brine. Currently, in the design phase, we’re deciding whether to employ the “lime-ammonium bicarbonate method” or the “soda ash-caustic soda method” for brine purification. The calcium removal tower used in the former method requires frequent cleaning, while the latter method involves relatively high treatment costs. In our company (well-bittern salt production), the brine purification method used was the soda ash-caustic soda method; later, the lime-flue gas method was adopted (as we have our own thermal power plant). Considering both the process stability and production costs, which brine purification method should be utilized? Thank you
I humbly request guidance from all the seniors! I need the moderator’s help
The brine at my former workplace was rock salt; the brine purification process utilized the two-alkali method, as the company itself produced soda ash and caustic soda. Therefore, from both economic and applicability perspectives, the two-alkali process was chosen. (Soda ash enterprises) Is your company a soda ash manufacturer? However, since it is a plant employing the ammonia-soda process, lime is readily available. But it’s unclear where ammonium bicarbonate can be sourced from. If it too is inexpensive and easily obtainable, its use is recommended. In terms of production stability, the two-alkali process has an advantage; this is something you need to weigh and consider. I suggest considering the following aspects when selecting a process: 1. The raw materials are inexpensive and readily available ； 2. Stable and easy to operate ； 3. The process is smooth and seamless.
This post was last edited by mkp369 on 2014-11-23 at 16:18. The ammonium carbonate-lime method is a technically established process; in this process, the off-gas from the carbonation tower is directed to a calcium-removal tower (for brine purification). Our company’s alkali plant is currently under construction, so I believe this process isn’t very suitable. Therefore, I would like to ask: our unit is a salt plant; we have used the lime-flue gas method before, and both types of alkali production methods are currently in use, with satisfactory results. However, I fail to understand why the ammonium carbonate-lime method—a variant of the ammonia-soda process—is employed for brine purification. Cleaning the calcium-removal tower is also troublesome, and the operating conditions are poor. Moreover, this method has adverse effects on subsequent processes after purification.
1# zhf5988478 The choice of method for refining brine using the ammonia-alkali process is primarily determined by the level of calcium and magnesium content in the raw salt; when the calcium and magnesium content is high, the use of lime and ammonium carbonate is more appropriate, while when the content is low, the lime-soda method is more suitable.
This post was last edited by mkp369 on 2014-11-23 at 16:19. What are the standards for the levels of calcium and magnesium? The combined calcium and magnesium content in my unit is around 5–6 g/L
This post was last edited by mkp369 on 2014-11-23 at 16:19. The information I’ve seen indicates that the soda lime method is more scientific; the ammonium carbonate lime method involves a complex process and requires a high investment of 5–8 million. Moreover, the purified brine contains no ammonia, which is beneficial for the carbonation process as well
It should be the carbonization process; moreover, the working environment is poor and the labor intensity is high!
Let’s share information on brine purification! Thank you
The advantage of the lime-ammonium carbonate method is that a portion of the ammonia in the carbonation off-gas can be recovered in the calcium removal tower. Additionally, it has low alkali consumption; after all, both two-alkali processes require the use of caustic soda or soda ash. To refine brine using flue gas, to what extent must that flue gas be treated?! !