Prarancangan Pabrik Asam Hidrofluorat dari Asam Sulfat dan Fluorspar dengan Kapasitas 30.000 Ton/Tahun

Ichsanul Fahri Khusaini, Ir. Wahyu Hasokowati, M.A.Sc., IPM.

2023 | Skripsi | TEKNIK KIMIA

Asam hidrofluorat merupakan senyawa yang banyak digunakan sebagai obat-obatan, herbisida, hingga berbagai macam prekursor organik dan inorganik, seperti Na3AlF6 (cryolite) dan AlF3 (aluminium trifluorida), PTFE (teflon), fluoropolymers, fluorocarbons, dan refrigeran berupa freon. Kebutuhan asam hidrofluorat meningkat 2,9% setiap tahun. 

abrik ini dirancang dengan kapasitas 30.000 ton/tahun dan beroperasi secara kontinyu selama 24 jam sehari dalam 330 hari/tahun.  Bahan baku utama yang digunakan berupa batuan fluorspar dan asam sulfat masing-masing sebanyak 29.624,83 ton/tahun dan 38.016 ton/tahun. 

Bahan baku batuan fluorspar dan asam sulfat direaksikan dalam reaktor rotary kiln pada suhu 200 derajatC dan tekanan 1 atm dengan media pemanas berupa udara panas yang bekerja secara direct heating. Produk yang dihasilkan berupa gas asam hidrofluorat dan gypsum sebagai produk samping. Produk gas asam hidrofluorat masih mengandung impurities sehingga perlu dilakukan pemurnian dengan beberapa tahapan yaitu kondensasi bertingkat, absorbsi, dan distilasi. Produk asam hidrofluorat memiliki kemurnian 99,93?n disimpan dalam kondisi cair dengan tekanan 5 atm.

Pabrik direncanakan akan berdiri di Kawasan Industri JIIPE, Kecamatan Manyar, Kabupaten Gresik, Provinsi Jawa Timur. Pabrik ini akan dibangun dengan luas lahan sebesar 3,8 Ha serta membutuhkan 320 orang karyawan. Kebutuhan listrik pabrik ini sebesar 1,12 MW yang akan disediakan oleh PT PLN Kabupaten Gresik. Kebutuhan untuk air ini disuplai dari air laut sebesar 17.366,38 kg/jam serta kebutuhan udara sebesar 19.021,33 kg/jam.

Evaluasi ekonomi diperoleh Fixed Capital sebesar Rp245.054.306.939,26 + US$17.253.344,50; Working Capital sebesar Rp5.927.502.981,03 + US$8.943.070,46; Manufacturing Cost sebesar Rp95.418.340.670,32 + US$63.829.375,64; General Expenses sebesar Rp22.161.693.815,96 + US$13.273.392,65; Total Production Cost sebesar Rp117.580.034.486,28 + US$77.102.768,30; serta nilai Sales sebesar US$100.054.181,47.  

Berdasarkan evaluasi ekonomi yang dilakukan, pabrik ini memiliki Return on Investment before tax sebesar 44,67%; RoI after tax sebesar 26,80%; Payout Time before tax sebesar 1,83 tahun; POT after tax sebesar 2,72 tahun; DCFRR sebesar 24,65%; Break Even Point sebesar 41,37%; dan Shut Down Point sebesar 24,31%. Berdasarkan analisis parameter kelayakan ekonomi diatas, maka disimpulkan bahwa Pabrik Asam Hidrofluorat dari Asam Sulfat dan Fluorspar ini layak dan menarik secara ekonomi untuk dikaji lebih lanjut.

Hydrofluoric acid is a compound that is widely used as a drug, and herbicide, to various organic and inorganic precursors, such as Na3AlF6 (cryolite) and AlF3 (aluminum trifluoride), PTFE (Teflon), fluoropolymers, fluorocarbons, and refrigerants in the form of freons. The need for hydrofluoric acid increases by 2,9% every year.

This plant is designed with a capacity of 30,000 tons/year and operates continuously 24 hours a day for 330 days/year. The primary raw materials used were fluorspar and sulfuric acid, respectively 29.624,83 tons/year and 38.016 tons/year.

The raw materials for fluorspar and sulfuric acid are reacted in a rotary kiln reactor at a temperature of 200 derajatC and a pressure of 1 atm with a heating medium in the form of hot air which works by direct heating. The products produced are hydrofluoric acid gas and gypsum as side products. The hydrofluoric acid gas product still contains impurities, so purification needs to be carried out in several stages, namely multilevel condensation, absorption, and distillation. The hydrofluoric acid product has a purity of 99.93% and is stored in a liquid state at a pressure of 5 atm.

The factory will be established in the JIIPE Industrial Area, Manyar District, Gresik Regency, East Java Province. This factory will be built with a land area of 3.8 hectares and requires 320 employees. The electricity requirement for this factory is 1.15 MW which PT PLN Gresik Regency will provide. The need for this water is supplied from seawater of 17,366.38 kg/hour and air demand of 19,021.33 kg/hour.

The economic evaluation gives a Fixed Capital of Rp245.054.306.939,26 + US$17.253.344,50; Working Capital is Rp5.927.502.981,03 + US$8.943.070,46; Manufacturing Cost is Rp95.418.340.670,32 + US$63.829.375,64; General Expenses is Rp22.161.693.815,96 + US$13.273.392,65; Total Production Cost is Rp117.580.034.486,28 + US$77.102.768,30; and Sales is US$100,054,181.47. 

Based on the economic evaluation conducted, this factory has a Return on Investment before tax is 44,67%; RoI after tax is 26,80%; Payout Time before tax value is 1.83 years; POT after tax is 2.72 years; DCFRR is 24,65%; Break Even Point at 41,37%; and Shut Down Point at 24,31%. Based on the analysis of the economic feasibility parameters above, it is concluded that the Hydrofluoric Acid Plant from Sulfuric Acid and Fluorspar is economically feasible and attractive for further study.

Kata Kunci : Asam Hidrofluorat, Asam Sulfat, Fluorspar, Gypsum