Simulation and Operation Cost Estimate for Phenol Extraction and Solvent Recovery Process of Coal-Gasification Wastewater

Abstract

To further reduce the total phenols of coal-gasification wastewater which comes from the Lurgi pressurized coal-gasification process, methyl isobutyl ketone (MIBK) instead of diisopropyl ether (DIPE) is used as the extraction solvent in the process to remove the phenols. To obtain process parameters for an industrial trial, process simulations with a treatment capacity of 100 ton/h wastewater are carried out. The simulation results show that with the use of MIBK as an extraction solvent, the total phenol concentration of coal-gasification wastewater can be reduced from 5410 ppm to less than 200 ppm. The operation cost estimate shows that using MIBK as an extraction solvent to extract and remove phenols from coal-gasification wastewater has good economic feasibility. With the process parameters obtained from the simulation, an industrial trial is implemented and satisfactory agreement is found. With the total phenol concentration reduced to below 200 ppm in the pretreatment, the coal-gasification wastewater can be decontaminated in the subsequent biological treatment.

Measurement, correlation and COSMO-SAC prediction of liquid-liquid equilibrium for the ternary systems, mesityl oxide + o-, m-, p-cresol + water, at 333.2K and 353.2 K

“…Such method has been used to treat industrial phenolic wastewater in USA [17], South Africa [17] and China [17][18][19]. The key problem to design a liquid-liquid extraction process is to develop an appropriate extractant with low water solubility, low price and high efficiency to separate cresols from water.…”

Measurement and thermodynamic modeling of ternary (liquid + liquid) equilibrium for extraction of o-cresol, m-cresol or p-cresol from aqueous solution with 2-pentanone

“…(Liquid + liquid) extraction has been used to treat phenolic wastewater in industry [2]. And it should be noted that, after the extraction process, a solvent stripping process is usually used to recover the solvent from the aqueous phase to avoid significant solvent loss, and the extraction solvent's concentration in the aqueous phase could be reduced to below 0.001 % (mass percent) [8] after the stripping process.…”

Thermodynamic and mechanistic studies on recovering phenol crystals from dilute aqueous solutions using pervaporation–crystallization coupling (PVCC) system

“…Among these techniques, adsorption with activated carbon or polymers appears to be competitive for treating wastewater at low phenol concentrations (usually o 1000 mg/L) in terms of rate of adsorption and frequency of regeneration of the adsorbents. Solvent extraction is an important technique widely investigated for disposal of high phenol concentrations (Jiang et al, 2003;Yang et al, 2013). Emulsion liquid membranes (Ho et al, 1982;Park et al, 2006) and supported liquid membranes (Yun et al, 1992;Nosrati et al, 2011) have also been investigated because of their advantages of low energy consumption and low operating cost.…”