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All Journal IPTEK The Journal of Engineering
Agung Subyakto
Institut Teknologi Sepuluh Nopember
Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Engineering Mechanical Engineering

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21 Bar Yoshimin Boiler Maintenance with Controlling Residual Phosphate Agung Subyakto; Afan Hamzah; Agus Surono
IPTEK The Journal of Engineering Vol. 6 No. 3 (2020)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j23378557.v6i3.a8117

Abstract

Boiler as the steam generator is usually utilized as a turbine drive and other industrial processes. Boiler needs good treatment and surveillance to keep its best performance. Boiler water (BW) and boiler feed water (BFW) quality control is essential in boiler maintenance since it preserves boiler from crust, corrosion, and carry over, moreover, it also prevents boiler pipe to break. Boiler maintenance in sugar refinery factory is carried out by controlling the quality of BFW, Chemical injection (inner maintenance) and blowdown of boiler water. BFW mineral content (SiO2 , total hardness) is maintained as small as possible using a softener (cation resin) or demineralization unit (cation and anion resin). Chemical injection is performed by the addition of soda in order to control the pH of boiler water. Phosphate addition aims to tie up total hardness level which is caused by concentration process of water boiler and slipped of hard water from BFW. Blowdown process has purpose to reduce crust and corrosion caused by mineral concentrate inside boiler. The experiment was conducted by controlling pH of BFW from 7.5-8.5, maximum total hardness at 3 ppm, maximum SiO2 concentration at 3 ppm and maximum Total Dissolve Solid (TDS) at 100 ppm while BW was controlled its pH at 10.5-11, maximum total hardness at 20 ppm, maximum SiO2 concentration at 50 ppm, maximum Total Dissolve Solid (TDS) at 2000 ppm, and residual phosphate ion between 4 – 10 ppm. The experiment time was adjusted as a milled day or about for 140 days. The result of the experiment showed that the treatment had a good impact on the condition of the boiler drum pipe.
Utilization of HVS Paper Waste for The Manufacture of Oxalic Acid Agung Subyakto; Fiqrotul Wasiyah; Linaniyyatul Masruroh
IPTEK The Journal of Engineering Vol. 7 No. 2 (2021)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j23378557.v7i2.a10067

Abstract

The purpose of this research is to determine the effect of time and temperature on the manufacture of oxalic acid from HVS paper waste by removing ink and alkali melting methods The research methodology began with the first stage, namely pre-treatment and then paper hydrolysis, weighing 600 grams of HVS paper waste. The HVS paper waste was put into a three-neck flask and 200 mL of 40% NaOH was added. The tools are assembled and set the time and temperature used. The time used is 60 minutes at a temperature of 55°C, 65°C, 75°C and 95°C, then a three-neck flask is heated. After heating is complete the solution is cooled. The filtrate was filtered into a 500 mL beaker glass then the remaining sediment was washed with hot aquadest into a beaker containing up to 400 mL of filtrate. The procedure was repeated for variations in time of 70, 80 and 90 minutes at temperatures of 55°C, 65°C, 75°C and 95°C, respectively. The second stage is crystallization of oxalic acid, pipette of the filtrate as much as 25 mL obtained from the hydrolysis results then added 10% CaCl2 to form a white precipitate of calcium oxalate. The precipitate was filtered then added 100 mL of H2SO4 4N so that the precipitate would break down into oxalic acid and calcium sulfate, then filtered and washed the remaining sediment using 96% ethanol. The filtrate is heated to a temperature of 70°C. The filtrate is cooled in ice water for about 24 hours to form oxalic acid crystals in the form of white needle crystals. The third stage is the calculation of the weight of oxalic acid (gr). The fourth stage is testing for oxalic acid using permanganate titration. Oxalic acid crystals were weighed as much as 0.3 grams then added 10 mL of distilled water and put into 250 mL Erlenmeyer, added 10 mL of H2SO4 4N. The solution is heated to a temperature of 60-70°C. In a hot state, the solution is titrated with 0.1 N potassium permanganate until the solution appears a pink color that does not disappear for 30 seconds. The fifth stage is the calculation of the yield (yield) of oxalic acid. The sixth stage is the melting test. The time and temperature in producing oxalic acid from the graph can be seen that the average temperature that produces the most oxalic acid is at 80 minutes and 65°C, which is 3.9 grams. The analysis results show that the melting point obtained is between 100-101 ° C. This happens because the oxalic acid in the research indicates that the oxalic acid corresponds to the actual melting point of oxalic acid based on the Indonesian National Standard (SNI), namely 101-102°C.
The Production of Gelatin from Snapper Scales (Lutjanus camphecanus Sp.) through Enzymatic Pretreatment Warlinda Eka Triastuti; Suprapto; Elly Agustiani; Lailatul Qomariyah; Agung Subyakto; Treisnaning Widasgantri; Marchel Abednego Septa K
IPTEK The Journal of Engineering Vol. 8 No. 1 (2022)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j23378557.v8i1.a12860

Abstract

Fish wastes such as fish bones and scales have a potential to be used as a gelatin source. It can be used as an alternative material to replace pork or bovine which ordinarily conflicted with religion issue. Gelatin from fish has different characteristics compared with mammalian source. It has several advantageous properties such as high amount of hydrophobic amino acids, less proline and hydroxy proline, lower gelling ability, and melting point. In this study, gelatin was produced from fish waste especially snapper scales using the bromelain enzyme at the pre-treatment stage to improve its characteristic. The snapper scales soaking in hot water at 80 degrees Celsius for about 30 minutes to remove the fat which attached the scales. A pre-treatment has been conducted using bromelain enzyme solution at various concentrations of 1 percent, 2 percent, 3 percent, 4 percent and 5 percent for 6 hours to remove non-collagenous proteins and loosen the bonds of the fish scales. The next step is demineralization using a 15 percent concentration of citric acid solution for 3 days. The ossein formed in the demineralization stage was then hydrolyzed at 50 degrees Celsius and 70 degrees Celsius for 9 hours with stirring at 300 rpm. The best gelatin yield was obtained from the pretreatment of bromelain enzyme solution with a concentration of 3 percent at a hydrolysis temperature of 70 degrees Celsius with a yield of 9.13 percent, pH value of 3.86, water content of 8 percent, ash content of 0.80 percent. FTIR spectra shows the presence of functional groups correspond to gelatin formation, such as carbon, hydrogen, hydroxyl group (O-H), carbonyl group (C=O), amine group (N-H) and alkene group (C=C). The heavy metal content test showed that the gelatin contained no heavy metal content of lead (Pb), mercury (Hg), cadmium (Cd) and arsenic (As).
Co-Authors Afan Hamzah, Afan Agus Surono Elly Agustiani Fiqrotul Wasiyah Lailatul Qomariyah Linaniyyatul Masruroh Marchel Abednego Septa K Suprapto Treisnaning Widasgantri Triastuti, Warlinda Eka