COAL TAR WASTE UTILIZATION BY CRACKING INTO FUEL SOURCE AND ITS SEPARATION USING FRACTIONAL VACUUM DISTILLATION METHOD AND ITS KINETIC STUDY

• Main Author: Ratnaningsih, Wahyu
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/53623
• Institution: Institut Teknologi Bandung

Coal tar is a hazardous and toxic waste, a by-product of coal gasification processes. Coal tar is a liquid waste produced in industrial fields such as steel, power plant, and cement industry. Coal tar is a black liquid , has a sharp and unpleasant odor, and it is a source of soil contamination because of its difficulty to perform degradation. Hence, it is a necessary to conduct coal tar utilization since this feedstock is abundant. Coal tar has a complex structure contains various kinds of hydrocarbon compounds with different functional groups as it seen as a potential source for fuel. Utilization of coal tar is needed, since coal tar is part of hazardous and toxic waste according to Government Regulation of the Republic of Indonesia No 101 of 2014 on Hazardous Waste Management, with the type of coal industry / processing through pyrolysis-coke production besides of its potential. This research is aimed to utilize coal tar by by cracking it into fuel source and to separate the fuel fraction using fractional vacuum distillation method. Coal tar characterization was needed as a preliminary research such as coal tar density (g/cm3), flash point (?), moisture content (%), and ash content (%). The low temperature lignite coal tar obtaining from iron and steel-based industry PT. XS Cilegon was pyrolysed using catalyst activated natural zeolite (2:10) at various temperatures of 350 ?, 400 ?, 450 ?, and 500 ?. The vapor flows through as a result of the heat and then were condensed in condenser at temperature of 20 ?. The pyrolysis product was distilled using Vigroux column at various reduced pressure of 160 mmHg, 140 mmHg, and 120 mmHg and various temperature of 340 ?, 370 ?, 400 ?, and 430 ?. Distillation kinetics were studied by distillation using various temperature at certain pressure starting from the temperature of the first distillate is formed, with a distillation time interval of 2.5 minutes until there is no formed distillate. Distillate is then collected in a bottle and the yield is calculated. The obtained fractions were analyzed using gas chromatography-mass spectroscopy (GC-MS), and the number of cetane index, flash point, pour point, viscosity, and sulfur were determined. The rate constant of middle oil recovery were determined using kinetic theory approach. Coal tar waste obtaining from steel production industry PT. XS has the density of 1.09 g / cm3, flash point of >180 ?, 25.34% of moisture content, and 1.41% of ash content. GC-MS results showed that the compounds in coal tar were dominated by polyaromatic hydrocarbons. The optimum operation condition for coal tar pyrolysis was obtained at temperatur of 450? with 79.55% yield and calorific value of 9509.95cal/g. The highest obtained distillation fraction of coal tar were middle fraction with calorific value of 11930.57 cal/g, density of 1.04 g/cm3, kinematic viscosity of 2.32 mm2/s, flash point of 104 ?, pour point of -19 ? and sulfur content of 0.6%. The dominant compounds of middle fraction were naphthalenes and its derivatives with the amount of 78.58% based on GC-MS result. The rate constant of middle oil recovery were increased with the increasing of temperature and the decreasing of pressure. The rate constant equation of middle oil recovery using Arrhenius equation at distillation pressure of 160 mmHg, 140 mmHg, and 120 mmHg were k= 4.6 × e(-(2449.6/T)), k= 4.4 × e(-(2413.2/T)), and k= 6.7 × e(-(1686.4/T)) respectively, with various temperature of 340 ?, 370 ?, 400 ?, and ? were k= 1.56 × 107× e(-(11232.5/T)), k= 5.07 × 106× e(-(10312.9/T)), k= 2.34×105× e(- (7261.7/T)), and k= 1.43×103× e(-(3989.1/T)) respectively. Based on economic analysis using Cost Benefit Analysis, coal tar utilization as an alternative fuel is beneficial with Net Present Value (NPV) Rp108.543.760.456, Benefit Cost Ratio (BCR) 2.97, Internal Rate of Return (IRR) 49.18%, and Payback Period (PP) 3.33.