SIROTHERM

Thermally regenerable ion-exchange resins or Sirotherm resins refer to a novel ion-exchange process which makes use of hot water as regenerant A comprehensive... 

Sirotherm is the ICI Australia Limited Trade Mark for thermally regenerable ion-exchange resins and associated plant... 

Sirotherm resins tend to be slowly oxidized by dissolved oxygen in raw water at the elevated temperature of regeneration this may be controlled by vacuum... 

As sirotherm resins are selective for higher valency cations (e.g., calcium and magnesium), it is difficult to remove both the cations which cause hardness in the same column 223.240) j q yjg resin capacity more economically, it is desirable to operate two columns in series, the first removing calcium and magnesium salts and the second removing potassium and ammonium salts. 

Typical performance data achieved in a laboratory scale with a single fixed-bed column are shown in Table 16. The performance data indicate that the sirotherm resin can produce water of salinity as low as 50 to 100 mg/1 dissolved salts. The operating capacity of the resins restricts the economic upper range of salinities to be treated between 2000 and 3000 mg/1. The resins can be used to treat hard water, although to remove salts of both divalent and monovalent cations the process should... 

Demineralization by ion exchange usually involves chemical regeneration of the resins with strong acid or alkali solutions. Weaker electrolyte regenerants are sometimes employed such as solutions of carbon dioxide, ammonia, or lime as demonstrated by various novel processes such as Desal and Carix for the partial demineralization, or desalination, of brackish waters. The increased dissociation of the salt forms of weakly functional cation and anion exchange resins at increased temperatures is the basis of the Sirotherm process which uses alternate... 

Ion exchange desalination - DESAL , SIROTHERM Membrane desalination - Reverse Osmosis, Electrodialysis Continuing fixed bed counterflow development Condensate polishing systems Ion Chromatography analysis, and Pellicular resins Polymeric adsorbents... 

Operating data indicate that Sirotherm TR-20 reins can produce waters of salinities as low as 50-100 ppm dissolved dalts, the economic upper range of salinities in feed water being restricted to 2000-3000 ppm. The resins are expected to find application in the demineralization of mildly brackish surface and underground waters for industrial and municipal use and as a roughing stage in the production of high-quality boiler feed water. 

Examples of major ion-exchange applications are listed in Table 13.2-1. The fidds of water treatment, effluent treatment, and pollution control are predominant and there have been many recent advances. For example, the partial demineralization of brackish water using the Sirotherm process has been developed in Australia and this is probably one of the most innovative developments in recent years. Important apfrii-cations in the fields of medicine, pharmacology, chemical processing, catalysis, and analytic techniques are also mentioned. The remainder of this section describes some impoitam applications in detail. 

Resins, U.S. Pat. 3,875,085 (1975). Anionic/cationic IPNs in semi-I form. Ion exchange resins weak acid, weak base. Phase separation synthesis. Improvement on Sirotherm process. 

Solid reagents in finely divided form are ideal for accelerating reaction rates, and can be conveniently handled by a composite particle or magnetic filler approach. The need to improve upon the inherently slow reactions in the SIROTHERM process has spawned a series of continuous versions of adsorption and coagulation processes, which radiate from the common magnetic particle axis. Of the ones described, the SIROFLOC clarification process has been the most successful, with the installation of full-scale plants in three countries. 

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