Supercritical Water Oxidation (SCWO) for Poly(ethylene terephthalate) (PET) Industry Effluents

Abstract

Supercritical water oxidation (SCWO) provides high destruction efficiencies for a wide variety of hazardous wastes at low reactor residence times. This paper studies the feasibility of the SCWO process for the treatment of the esterification wastewater from the poly(ethylene terephthalate) (PET) industry, for which the major contaminant product is ethylene glycol. Both the feed and the liquid-phase product were analyzed in terms of total organic carbon (TOC) to determine the efficiency of the process. Effluent from the PET industry contained 16000 mg/L TOC, equivalent to 4 wt % ethylene glycol. Experiments were carried out in a pilot plant equipped with a pressure shell and a cooled-wall reactor. The effects of temperature and oxidant concentration on removal efficiency were investigated. Tests were performed in the range of 550−750 °C at a pressure of 23 × 106 Pa. Results showed elimination efficiencies of up to 99.9% at 630 °C and residence times of less than 50 s. The scale-up of this plant has been simulated using the software Aspen Plus.

Supercritical water oxidation: A technical review

“…A scheme of the cooled-wall reactor's behavior is shown in Figure 7. The cooled-wall reactor was developed in a 30 kg/h pilot plant and tested with industrial wastes such as cutting oils and PET effluents, 20,87,88,126 obtaining excellent results. In 2001, the cooled-wall reactor was scaled-up to work in a demonstration SCWO plant located in the site of the firm CETRANSA in Santovenia de Pisuerga (Valladolid, Spain), with a treatment capacity of 200 kg/h of waste.…”

Destruction of an industrial wastewater by supercritical water oxidation in a transpiring wall reactor

“…In the last few years, some commercial applications have been studied [3,4] and computer models have been developed in order to scale-up [5]. * Our group have been working in the SCWO process since 1994, developing a cool wall reactor for SCWO in a 30 kg/h pilot plant and tested it with industrial wastes such as cutting oils and PET effluents [6][7][8] obtaining excellent results. In addition, a demonstration plant [9,10] located in an industrial site in Santovenia de Pisuerga (Valladolid, Spain) was constructed to treat 200 kg/h of waste.…”

Reacting flow simulations of supercritical water oxidation of PCB-contaminated transformer oil in a pilot plant reactor

“…Supercritical water oxidation (SCWO) is thus considered to be one of the most promising technologies for treating toxic industrial wastes that cannot be handled by means of the conventional endof-pipe technologies (Cocero et al, 2000, Veriansyah et al, 2005, Brunner, 2009). …”