Preliminary Study of Dry Sorbent Injection and Limestone Forced Oxidation Comparison for Coal Fired Steam Power Plant Retrofit

To meet SO₂ emission new regulation, Indonesian CFSPP shall be upgraded with a new desulfurizer equipment (if not there before) or increase the capture ability (existing equipment). SO₂ concentration required in the previous regulation was maximum 750 mg/Nm³, and then revised with the new regulation with the numbers of 550 mg/Nm³ (existing power plant) and 200 mg/Nm³ (new power plant). Couple desulfurization methods were studied, they are dry sorbent injection (DSI) using sodium bicarbonate (NaHCO₃) and limestone forced oxidation (LSFO). With using Palu 3 CFSPP coal basis, specific SO₂ concentration was estimated. From the study it was concluded that LSFO is cheaper in sorbent consumption cost than DSI. It was proven estimation of both desulfurization methods to comply 550 mg/Nm³ regulation, LSFO will cost $ 53.18 per hour and the sorbent price will be $ 0.12/kg SO₂ while DSI will cost $ 743.13 per hour and $ 1.68/kg SO₂. Despite expensive, DSI is easier method to be applied in existing power plant meanwhile LSFO is more difficult due to need of massive equipment, big space, and more capital cost.