Optimization of VOC removal using novel, low-cost sorbent sinks and active flows

Abstract

Volatile Organic Compounds (VOC) are air pollutants common to indoor environments like nail and beauty salons. In these locations, air quality is usually controlled through natural or mechanical ventilation. Previous studies investigated adsorbent materials to augment VOC removal. The objective of this study was to evaluate the VOC removal capability of a novel, low-cost plaster matrix treated with activated carbon (AC) using acetone as model VOC. The experiments were conducted in a closed chamber under passive and active flow conditions. Optimization parameters including mass of AC in sink mixture and external surface area (SA) of sink were studied. Two different mass removal rate equations (mass-normalized and surface area-normalized) were determined from experimental data, using nth-order general rate models with VOC concentration in air and VOC mass adsorbed as fit parameters. These equations were then used in a mathematical model to predict impact of sorbent sinks in a typical nail salon. In-situ regeneration of the sink via resistance heating was also investigated.Results showed that VOC removal by sorbent sinks increased with external surface area and with thickness to lesser extent. Active flow conditions also enhanced VOC removal from the air. The model results indicated that sorbent sinks provided significant VOC removal in a 1400 m3 nail salon but required a SA of approximately 25 m2. Estimated effective ventilation rates from the model ranged 3.32–9.03 mg m−2 h−1, similar to values reported in a previous study. Regeneration tests were inconclusive but indicated that some VOC adsorption may not be easily reversible.