Salt Separation During Supercritical Water Oxidation of Human Metabolic Waste: Fundamental Studies of Salt Nucleation and Growth

Oxidation kinetics of ammonia and ammonia-methanol mixtures in supercritical water in the temperature range 530-700.degree.C at 246 bar

“…The fundamentals of salt nucleation, precipitation, and growth in supercritical water are currently being studied by Armellini and Tester (1990). In this paper, the oxidation kinetics of ammonia and ammonia-methanol mixtures in supercritical water are presented and discussed.…”

Utilization of geopressured resources in the oxidation of organic waste in supercritical water. Phase I, Final report

“…The heat of oxidation raises the temperature of the system to about 600 0 C (1100 0 F). Due to the low solubility of inorganic salts in supercritical water (about 200 ppm or less) (Armellini and Tester, 1990, 1991a, 1991b, solid salt forms and falls to the lower section of the reactor, where it is cooled and quenched with water, creating a concentrated (organic-free) brine that would be mixed with brackish water and reinjected back to the geopressured well. Power is generated by the expansion of the products of the SCWO process through a series of multi-stage turboexpanders.…”

“…In addition, we plan to develop models for the precipitation of salt in a reacting supercritical water stream using data obtained by our research group (Armellini and Tester, 1990, 1991a, 1991b. Salt separation is a key engineering design consideration in the operation of the SCWO process (Hong et aL, 1989).…”

“…Earlier in the mid-1970's, investigators in chemical engineering at MIT actually reduced the concept to practice in the first patent (Amin, Reid and Modell, 1978) which led to the establishment of a new company, MODAR, Inc. in 1980 and a series of additional patents on the process itself (Modell, 1982(Modell, , 1985. Our research group was the first to actually measure kinetic rate constants for the oxidation of methane, carbon monoxide, ammonia, hydrogen, ethanol, and methanol in supercritical water (Helling and Tester, 1986Webley and Tester, 1988Webley et aL, 1990Webley et aL, , 1991 Holgate and the first to observe salt formation and separation in mixed supercritical water jets in an optically accessible cell (Armellini and Tester, 1990, 1991a, 1991b. A comprehensive review of the technology has been prepared in a collaborative effort of the MIT group, MODAR, and ABB Lummus Crest (Tester et aL, 1992).…”

Supercritical Water Oxidation of Solid Particulates

“…SCWO achieves similar conversion at a lower temperature, essentially eliminating the formation of NO x and SO 2 . However, corrosion of the reactor [Mitton et al, 1994] and the formation of sticky salts [Armellini and Tester, 1990] can be a problem in a SCWO system.…”