A Simple One-Dimensional Model for Investigation of Heat and Mass Transfer Effects on Removal Efficiency of Particulate Matters in a Venturi Scrubber

Abstract

<span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>In the present study a mathematical model is developed in order to examine the effects</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>of heat and mass transfers on removal efficiency of particulate matters in venturi type</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>scrubbers. The governing equations including the variations of the particulate</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>concentration, gas temperature, droplet temperature, diameter, and velocity are</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>obtained based on the conservation laws and are solved numerically. In order to</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>validate the model, necessary data was measured and collected in a commercial cement</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>plant that uses these types of scrubbers in air pollution control applications. A good</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>agreement between plant data and the model predictions is noticed in general. The</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>results obtained from the model reveal that the existance of temperature difference</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>between the gas and the liquid droplets decreases the overall removal efficiency of</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>particulate matters. This is due to sudden reduction ofrelative velocity between the gas</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>and droplets which is resulted from the existence ofheat and mass transfers between the</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>two fluids, especially in the throat section. In addition, the effects ofvarious operating</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>parameters on the extent ofreduction in the removal efficiency are examined. This study</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>confirms that in most industrial applications ofventuri scrubbers it is necessary to use a</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>direct or an indirect cooling tower in order to decrease the gas temperature before</em> <span style="font-size: 10pt; color: #000000; font-style: normal; font-variant: normal;"><em>entering the venturi.</em></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><br style="font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" /><br class="Apple-interchange-newline" /></span>