Analisa Ketebalan Steam Chest sebagai Fungsi Breakthrough Time pada Steam Injection Process

The thickness of steam chest is found by integrating the steam velocity with respect to breakthrough time. The bigger rate of steam injection would form the thinner steam chest, which has affected to the cost required to production of steam that would be injected to the reservoir. There is a difference between the theoretical breakthrough time and steam chest calculations with the actual field situation. The difference occurs because in the theory used the ideal condition in which the heat efficiency is perfect, but in the actual field, there are many factors that cause the heat efficiency such as the slope of layers, reservoir heterogeneity, pressure gradient, and permeability distribution

Penentuan Oil Losses dan Faktor Koreksi Pada Jalur Pipa Pengiriman Minyak Mentah di Sumatera Selatan

Crude oil delivery system in South Sumatra by using the same pipes for oil companies raises the problem that is the loss of oil (oil losses) between Gathering Station as a delivery point with Center Production Gathering system.  At this time there has been a change in the crude oil shipping operations both in production volume and the number of business partners involved in the delivery of crude oil. Changes in crude oil shipments were caused either by the discovery of petroleum source of new, decreasing oil production, changes in the volume of oil delivered and others resulted in a correction factor of production calculated at an earlier time is not representative anymore and needed re-evaluation.Conducting a study on the factors reevaluation oil losses in some parts of the oil field consisting of several groups (Segment) to determine the correction factor based on the production of oil properties, operating conditions and delivery process are other factors that influence it. The correction factor consists of oil shrinkage,water and sediment,  emulsion and evaporation

Evaluasi Waktu Start Up pada Proses Peruraian Stillage secara Anaerobik Menggunakan Reaktor Fixed Bed dengan Zeolit sebagai Media Imobilisasi

Stillage was a waste containing high organic load and thus potentially as substrate anaerobic decomposition. However the complexity of the compounds contained therein has caused the decomposition process was slow.The study was conducted to evaluate the effect of substrate concentration to performance and the start up time required in fixed bed reactor with zeolite as immobilization media for stillage decomposition. The evaluation of the fixed bed reactor performance was executed by comparing experimental data and simulation result from the mathematical modelling as the standard under ideal condition for anaerobic stillage decomposition that has been compiled. The start up phase was conducted in the circulated batch system in two cycles with different substrate concentrations. Based on the evaluation, the first cycle with  the substrate concentration of 11.900 mg sCOD/L required 7-10 days to start up. If the first cycle had been conducted in more than 10 days, the condition was not optimum and it led to the death of microorganism. In the second cycle start-up phase with concentration  of the substrate of 17.600 mg/L sCOD in the reactor resulted in the failure of the system due to organic shock loading. From this study, it is obtained the  substrate with low concentration, 10.000 mg/L was good to start up

Effect of Temperature, pH, and Salinity on Adsorption of Textile Dye onto Biosilica

This research presents the adsorption of Direct Red-31 dye with biosilica adsorbent from rice husk ash. Direct Red-31 dye is azo dye, which is frequently used in textile industry. Rice husk ash is used as asdorbent, because of the abundant existence of rice husk in Indonesia and it is easy to get. This research was run in batch process with dye concentration 20 ppm and adsorbent mass 10 g/L. The research was performed with pH variation (2, 3, 4, 5,  and 6), variation of salt (NaCl, NaNO3, and Na2SO4) and temperature variation (35, 40, 45, 50, and 55 oC). From the research result, the optimum pH of the adsorption is at pH 2 with percent removal 83.949%. Adsorption process with addition of Na2SO4 salt increases the removal percentage to 87.714%. For the temperature effect analysis, the positive value of ΔG indicates the non spontaneous adsorption, the entalphy (ΔH) value of 11.8 kJ/mol indicates the adsorption was physical and endothermic. Entropy (ΔS) value of 0.03101 kJ/mol indicates structural changes on the surface of the adsorbent

Adsorpsi Ion Logam Kromium (Cr (Vi)) Menggunakan Karbon Aktif dari Bahan Baku Kulit Salak

Heavy metals are elements which are produced in industrial waste. This heavy metal waste causes pollution to the environment if the content of heavy metals contained therein exceeds the threshold. The toxic’s properties are extremely dangerous for humans if it accumulates in the human body. One of the heavy metals that are produced  is chromium. Several chemical and biological methods to remove heavy metals contained in the waste have been found. The adsorption method is one of the efficient and effective ways to treat heavy metal waste. In this study, activated carbon was prepared from salacca peel. Effects of pH, adsorbent dosage and Cr(VI) concentration on the adsorption of hexavalent chromium were investigated. The results were analyzed with Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich adsorption isotherm models. And kinetic of the adsorption was performed based on pseudo first order, pseudo second order, and intraparticle diffusion equations. From the research, it is known that the optimum conditions for the Chromium(VI) adsorption occurs at pH 2. The adsorption capacity of salacca peel based activated carbons for the removal of hexavalent chromium was found to be 123 mg/g. And the best adsorption isotherm which can represent the adsorption equilibrium is Langmuir isotermal adsorption model. Moreover the data indicated that the adsorption kinetics follow the pseudo second orde

Conversion of Ligno-cellulosic Biomass Waste into Cellulose Nano-Fibril (CNF) Biodegradable Film for Bioactive Food Packaging

Indonesia is rich in tropical fruit. However, many tropical fruits face a post-harvesting problem related to the short shelf-life of fruits due to the high respiration, transpiration, and decaying by fungi. To solve this problem, it is necessary to prolong the shelf-life of tropical fruit by applying bioactive food packaging which can prevent fruit from decaying and rotting. Among the prospective bioactive food packaging is biodegradable film made of cellulose nanofibril (CNF). CNF is new nanomaterial containing thin fiber from cellulose. This material forms transparent gel, thus it is easily to be modified into biodegradable film which is homogenous, safe, environmentally friendly, and renewable. CNF nanomaterial can be derived from lingo-cellulosic material through the process of lingo-cellullose degradation followed by homogenization using fluidization process. This process results in CNF transparent gel which can be readily modified as biodegradable film. This biodegradable film is then can be applied to the tropical fruits to prolong their shelf-life. CNF bioactive food packaging has high mechanical strength and high protection against oxidation process. This paper comprehensively reviews the advanced technology of upgrading lingo-cellulosic biomass waste into CNF biodegradable film and the technic of applying it as bioactive fruit packaging

Peran Perguruan Tinggi dalam Penurunan Emisi Gas Rumah Kaca Melalui Pengelolaan Sampah Kantin

Higher education institutions can play a role in reducing greenhouse gas emissions through solid waste management. One of the solid waste sources in the campus is a canteen. Surabaya University (Ubaya) is one of the higher education institutions in Surabaya has two canteens that generate waste everyday. In the canteen waste is separated into food waste, food cardboards and plastic bottles. Food waste and food cardboards has not processed yet. A research related to the potential utilization of canteen waste need to be  conducted. The aims of the research are  determining the amount of organic waste generation in Ubaya canteen and calculating the greenhouse gas that can be derived if organic waste is processed into biogas. The scope of calculation was CH4 generation. The research is conducted in the Keluwih Canteen.  The estimation of canteen waste is taken for ten days. The surveys conducted during November 2017. The calculation of green house emission from solid waste was referred to Intergovernmental Panel on Climate Change (IPCC)  2006 guidelines.  The results of the research indicated that the average quantity of food waste is 6,3 kgs per day, 5  kgs per day of food cardboards and  Surabaya University can contribute to reduce green house gas emission (CH4) about 0,85 kg CH4 per day

An Innovative Approach for Modeling Ultrasonic-assisted Drying

Drying is a simultaneous heat and mass transfer process which involves significant energy consumption. For sustainable processing practice, ultrasonic-assisted drying is often implemented. In order to assist in process design and optimization, a physically-meaningful drying model is useful. The REA (reaction engineering approach), which has been shown to be accurate to model several challenging drying cases, is implemented here to model the ultrasonic-assisted drying with various intensities. The relative activation energy (ΔEv,b) generated from one accurate drying experiment is used to model the ultrasound-assisted drying with various intensities. The results of modeling match very well with the experimental data. The REA is accurate to model the ultrasonic-assisted drying under various intensities (i.e. 8, 12, 21, 29 and 31 kW/m3). The mechanisms of ultrasonic-assisted drying can be explained well by the REA. A landmark for process intensification of drying process has been set up by the REA. The model can be readily adopted in industrial settings for process design and optimization

Karakterisasi Bio-Oil dari Hasil Pirolisis terhadap Biomasa

The utilization of biomass as a source of new and renewable energy is being carried out. One of the technologies to convert biomass as an energy source is pyrolysis which is converting biomass into more valuable products, such as bio-oil. Bio-oil is a liquid which produced by steam condensation process from the pyrolysis of coconut shell. The composition of biomass such as hemicellulose, cellulose and lignin will be oxidized to phenol, alcohol, and acetate acid as the main content of the bio-oil. The experiments typically occurred at the atmospheric pressure in a laboratory furnace at temperatures ranging from 300 to 550oC with a heating rate of 10oC/min and a holding time of 1 hour at the pyrolysis temperature. The Gas Chromatography-Mass Spectroscopy (GC-MS) was used to analyze the bio-oil components. The obtained bio-oil has the viscosity of 1.185 cp (coconut husk), 1.133 cp (coffee husk), 1,094 cp (sawdust); the density of 1.008 g/cm3 (coconut husk), 0.994 g/cm3 (coffee husk), 0.98 g/cm3 (sawdust);the caloric value of 3500kcal/kg (coconut husk),4200 kcal/kg (coffee husk), 1500 kcal/kg (sawdust); and the moisture content of 16% (coconut husk),31% (coffee husk),13% (sawdust). The analysis of GC-MS result showed that the bio-oil from coconut husk contained ethyl ester (37.60%), phenol (40.01%); bio-oil from coffee husk contained acetic acid (26%), phenol (34%); and bio-oil from sawdust contained acetaldehyde (26.15%), acetic acid (20.90%)

Pengaruh Suhu Dan Komposisi Minyak Jagung Pada Pembuatan Lilin Klowong Terhadap Pewarnaan Batik

Batik is one of the most highly developed Indonesian art forms that had been designated by UNESCO as a Masterpiece of oral and intangible Heritage of Humanity. It uses techniques of wax resist dyeing applied to the whole cloth and can be made by using canting or printing.Once the design applied on the cloth, then it is ready to be waxed and the staining of the batik cloth depends on the quality of the wax. Therefore, batik wax is considered as the main material to make batik, especially for handmade batik in which the pattern and carve applied directly by the artisans.  Vegetable oil is to improvement viscosity level in liquidity of batik waxes and to knowing the effect of the dyed batik.This research aims to knowing the composition of the required yellow paraffin waxes batik and to knowing the effect of the composition of the yellow paraffin dyed batik. This study uses qualitative and quantitative methods with material measurement techniques, and test a questionnaire to evaluate the response of the respondents to the sharpness of the color produced. In the process of making batik wax, the composition of the materials used are Lilin tawon, damar mata kucing, gondorukem, yellow parafin, and  vegetable oils. In this research, yellow paraffin as an independent variable with variations in different compositions (10 g, 15 g, 20 g and 25 g). To test the composition of the wax batik then made 4 different samples, each sample has a different composition yellow paraffin. To view a sample of the batik conducted several tests, including testing the sharpness of color, smearing of colors, as well as washing with soap, while the qualitative testing done by kuisioer to test visually, from the test results of samples both quantitative and qualitative data show that the results of batik using sample C gives better results than other samples