Prarancangan Pabrik Kimia Magnesium Sulfat dari Magnesium Karbonat dan Asam Sulfat Kapasitas 50.000 ton/tahun

FIKA RACHMADIAN PUTRI, Yuni Kusumastuti, S.T., M.Eng

2014 | Skripsi | TEKNIK KIMIA

Prarancangan pabrik magnesium sulfat dari asam sulfat dan magnesium karbonat ini bertujuan untuk mengkaji lebih lanjut kelayakan pabrik untuk didirikan. Pabrik dirancang dengan kapasitas 50.000 ton/tahun dan beroperasi secara kontinyu selama 330 hari/tahun dan 24 jam/hari. Secara umum tahapan proses produksi magnesium sulfat heptahidrat terdiri dari reaksi anrara dolomit dan asam sulfat, kristalisasi dan pemurnian produk. Produk magnesium sulfat heptahidrat dengan kemurnian 99% sebanyak 50.000 ton/tahun memerlukan dolomit sebanyak 51.476,72 ton/tahun, asam sulfat 98% sebanyak 23.930,21 ton/tahun. Bahan pembantu yang diperlukan adalah air sebanyak 57.410,71 ton/tahun. Sebagai penunjang, unit utilitas menyuplai kebutuhan air sebanyak 198.051,77 ton/tahun, solar sebanyak 4849,8278 ton/tahun dan listrik sebesar 595 kwh. Pabrik akan didirikan di Kawasan Industri Gresik, Jawa Timur, dengan lahan seluas 40.000 m2. Jumlah pekerja sebanyak 213 orang. Berdasarkan perhitungan evaluasi ekonomi, pabrik magnesium sulfat heptahidrat ini tergolong low risk dengan Fixed Capital Cost sebesar Rp 67.942.14.158,57 + $ 11.689.588,07 ; Working Capital Cost sebesar Rp 70.448.502.187,65 + $ 6.617.787,70; Pada kapasitas produksi 100%, nilai ROI sebelum pajak diperoleh sebesar 26,03%; POT sebelum pajak adalah 2,78 tahun; BEP 48,78%; SDP 22,96% dan DCFRR 26,11%. Berdasarkan nilai-nilai di atas, dapat disimpulkan bahwa pabrik ini menarik secara ekonomi dan layak untuk dikaji lebih lanjut.

Preliminary design of this magnesium sulfate plant is inteded to asses the feasibility of this plant.. This plant is designed with capacity of 50.000 tons/year and to be operated continously 330 days/year and 24 hours/days. In general, magnesium sulfate heptahydrate manufacturing stages process goes as follows: reaction between dolomite and sulphuric acid, crystallization and purification. In order to gain the magnesium sulfate heptahydrate product as designed capacity with 99%(w/w) purity, 51.476,7200 tons/year of dolomite and 23.930,21 tons/year of 98%(w/w) sulfuric acid are required as main raw material. Moreover, the supporting material required is 57.410,71 tons/year of water. As a support, utility plant unit supplies water as much as 198.051,77 tons/year, 4849,8278 tons/year of diesel oil and 595 kwh of electricity. The plant will be established in Gresik Industrial Area, East Java, with 40.000 m2 area and employs 213 people. Based on economic evaluation, this plant is classified as low risk plant with fixed capital required equal to 67.942.14.158,57 + $ 11.689.588,07; and working capital equal to Rp 70.448.502.187,65 + $ 6.617.787,70; At 100% production rate, obtained ROI before tax is 26,03%; POT before tax is 2,78 years ; BEP at 48,78%; SDP at 22,96% and 26,11% of DCFRR. From those points, it can be concluded that preliminary design of this magnesium sulfate plant is worth to be studied further

Kata Kunci : asam sulfat, magnesium karbonat, magnesium sulfat, prarancangan pabrik