PENGARUH PENAMBAHAN LIMBAH BIOMASSA TERHADAP STRUKTUR KARBON BIOKOKAS MENGGUNAKAN BATUBARA NON COKING

• Main Author: Rizal Muharam, Syamsul
• Format: Theses
• Language: Indonesia
• Subjects: Metalurgi
• Online Access: https://digilib.itb.ac.id/gdl/view/54279
• Institution: Institut Teknologi Bandung

Metallurgical coke is a porous carbon material from coking coal at high temperatures (900-1200oC) which has 3 main functions i.e. thermal function, chemical function, and physical function. The existence of coking coal has decreased and raising price of coking coal. Steel production has increase every year so as to produce CO2 gas emission around 2.0–2.3 Giga ton/year. Indonesia has coal deposit 39,891 Bt and Indonesia has forestry area reached 147 Million hectares it’s expected Indonesia can produce 146,7Mt of biomass per year. Based resources of coal and biomass in Indonesia and to reduce greenhouse gas emission and to reduce import dependency of metallurgical coke, the creation of bio-coke by non coking coal blending with biomass can be an alternative solution to be applied. In this study, non coking coal will be blended with several variation (5, 10, 15, 20, and 25%) of carbonized biomass waste like coconut shell and rice husk at 500oC with -60 mesh size and adding 25% molasses as binder. All sample was blended and briquetted with load pressure 300 kg/cm2 by re-carbonized at 1000oC for 1 hour to produce 2 kind solid materials as coconut shell bio-coke (BTK500) and rice husk bio-coke (BSP500). Each bio-coke sample characterized by proximate, ultimate, and calorific value analysis, compressive strength analysis for coke strength testing, and to measure the quality of bio-coke by FTIR analysis for functional group, XRD analysis for carbon structure, and SEM analysis for morphology of bio-coke surface. Experiment results shown that bio-coke have yield range 55,75%-64,18% (BTK500) and 55,89%-69,08% (BSP500). Bulk density from each sample of biocoke range from 1,17-1,3 g/cm3 (BTK500) and 1,18-1,39 g/cm3 (BSP500). For calorific value of bio-coke range 6281,68 – 6583,51 cal/g (BTK500) and 4898,81 – 5557,44 cal/g (BSP500) respectively. In addition, for compressive strength results decrease along with increasing of biomass addition have range from 23,68 – 11,68 MPa (BTK500) and 20,21 – 9,83 MPa (BSP500). In quality test, FTIR analysis shows change in peak intensity of functional group in bio-coke respectively by wavenumber 3800 cm?1 (Al-O), 3725 cm?1 (Al-O), 3425 cm?1 (-OH), 2930 cm-1 (- CH2), 2380 cm?1 (CO2), 1580 cm?1 (C=C), 1430 cm-1 and 1240 cm-1 (-CH3), 1080 cm?1 (Si-O), 790 cm?1 (-CH3) and 470 cm?1 (SI-O-Al). All analysis bio-coke of XRD show the interlayer spacing (d002) of the aromatik structure range 3,52 ? 3,62 Å, for the stacking height of crystal (Lc) 9,96 ? 10.87 Å, crystallite size (La) 35,18 ? 37,87 Å, and ratio of aromatization bio-coke 0,42 – 0.48. while the SEM analysis shows that all bio-coke product has coarse and grainy irregular surface morphology with cracks and pores formed the present of many and large size pore will decrease compressive strength value. So, that the compatibility to metallurgical coke is approaching but not still not reached yet.