Combination of in situ iodization and Haloferax spp. bacteria enrichment in salt crystallization process

Salts that meet the standard quality are enriched with micronutrients, such as potassium iodate, at least 30 ppm. The iodization can be carried out directly in crystallization ponds (in-situ iodization) in salt fields. This paper reports the effectiveness of in-situ iodization technology combined with the enrichment of Halophilic bacteria consortium and Haloferax spp. to produce bio-based NaCl salt. The brine was first crystallized under sunlight exposure for approximately five days with water temperatures of 32-39 °C and an average wind speed of 2.8-6.0 m/s in each pond with a dimension of 20 × 20 m. Following this, the performance of these bacteria was analyzed in terms of the resulting final concentration of KIO₃ (ppm), NaCl concentration (v/v), and water content (v/v). Results showed that the treatment with in situ iodization and Haloferax spp. successfully produce better bio-based salt quality in terms of KIO₃ level, NaCl purity, and water contents. Moreover, the method did not produce aqueous and solid wastes, unlike in the conventional salt industry. The optimum condition was found at 50 ppm of KIO₃ with the addition of Haloferax spp. SEM analysis shows that the treatment using Haloferax spp. resulted in a larger rectangular and harder crystal salt than the controls.