Supercritical water technology

Peterson AA, Vogel F, Lachance RP, Froling, M, Antal MJ Jr, Tester JW. Thermochemical biofuel production in hydrothermal media a review of sub- and supercritical water technologies. Energy Environ Sci. 2008 1 32-65. 

Recent Progress in Transformation of Lignocellulosics to Fuels and Chemicals by Supercritical Water Technology... 

In order to use biomass in an environmentally friendly manner, various chemical-free approaches for lignin extraction have been applied. Pure subcriticai water and supercritical water technologies (Aquasoiv) have recently received increasing attention based on earlier research [41,44 7, 56-65]. Subcriticai water and supercritical water behave very differently... 

With respect to dense phase fluids, supercritical water has been shown to be a very effective reaction medium for oxidation reactions [8, 9]. Despite extensive research efforts, however, corrosion and investment costs form major challenges in these processes because of the rather extreme operation conditions required (above 647 K and 22.1 MPa) [10]. StiU, several oxidation processes for waste water treatment in chemical industries are based on supercritical water technology (see, e.g., [11]). 

Jian Jin, Xiaodong Li, Yong Chi, Jianhua Yan, Heavy metals stabilization in medical waste incinerator fly ash using alkaline assisted supercritical water technology. Waste Management Research 28... 

The two fluids most often studied in supercritical fluid technology, carbon dioxide and water, are the two least expensive of all solvents. Carbon dioxide is nontoxic, nonflammable, and has a near-ambient critical temperature of 31.1°C. CO9 is an environmentally friendly substitute for organic solvents including chlorocarbons and chloroflu-orocarbons. Supercritical water (T = 374°C) is of interest as a substitute for organic solvents to minimize waste in extraction and reaction processes. Additionally, it is used for hydrothermal oxidation of hazardous organic wastes (also called supercritical water oxidation) and hydrothermal synthesis. 

FIG. 22-25 Hydr othermal-oxidation process (also called supercritical water oxidation) for wastewater purification. (Cowtesy Eco-Waste Technologies.)... 

Supercritical technology, 23 242,13 449 Supercritical water (SCW) properties, waste detoxification and, 14 108 Supercritical water oxidation (SCWO), 24 16-17... 

Figure ES-2 is a block diagram of the Eco Logic technology process. The primary treatment destroys the agent and the energetic materials by hydrolysis with caustic or water. Flowever, the hydrolysis products (hydrolysates) must be further treated prior to final disposal. For this secondary step, Eco Logic proposes to use a transpiring-wall supercritical water oxidation (SCWO) reactor design. The following major operations are included ...

NRC. 2001d. Assessment of Supercritical Water Oxidation Technology Development for Treatment of VX Hydrolysate at the Newport Chemical Agent Disposal Facility. Letter Report of the Committee on Review and Evaluation of the Army Chemical Stockpile Disposal Program. Washington, D.C. Board on Army Science and Technology. 

Recently, the supercritical fluid treatment has been considered to be an attractive alternative in science and technology as a chemical reaction field. The molecules in the supercritical fluid have high kinetic energy like the gas and high density like the Uquid. Therefore, it is expected that the chemical reactivity can be high. In addition, the ionic product and dielectric constant of supercritical water are important parameters for chemical reaction. Therefore, the supercritical water can be realized from the ionic reaction field to the radical reaction field. For example, the ionic product of the supercritical water can be increased by increasing pressure, and the hydrolysis reaction field is realized. Therefore, the supercritical water is expected as a solvent for converting biomass into valuable substances (Hao et al., 2003). 

T0750 Stevens Institute of Technology, Trench Bio-Sparge T0751 Stevenson Palmer Engineering, Inc., PHOSter T0756 Supercritical Water Oxidation—General... 

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