| Abstract:
Mazandaran wood and paper industry is an integrated and the largest manufacturer of paper in the Middle East. Chemical and energy recovery of black liquor is one important aspect of wood pulping which has been intensively studies. Liquor concentration is the most important step in chemical and heat recovery which is used in Mazandaran wood and paper industry. In this work, liquor concentrator unit was simulated by Hysys software. Then, simulation results were compared with factory data and acceptable results were obtained. In the next step, the effect of operating conditions of the two main feed streams was studied. The results showed that with increasing of weak liquor temperature, the concentration of outgoing liquor flow increases as per 40° C increasing of temperature, as much as 28% of the condensed value was increases. Also, by 10 kPa increase of the weak liquor pressure, approximately 39% of condensed value decreases. By increasing the pressure and flow rate of steam, concentration of outgoing liquor increases, while, increasing for flow rate was sharply increased followed by lower rate of increase. The effect of steam temperature on the concentration of outgoing liquor at different pressures must be checked individually.
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