Chemical Engineering Commons^™

Impact Of Sludge Treatment Processes On Estrogen Concentration In Wastewater Sludge, Erica Marti

College of Engineering: Graduate Celebration Programs

Endocrine-disrupting compounds (EDCs), such as estrogen, are known to be present in the aquatic environment at concentrations that affect fish and other wildlife. For example, juvenile male fish exposed to estrogen will synthesize vitellogenin, which is a female-specific protein. Estrogen exposure is also linked to sex reversal, intersexuality, and inhibition of gonadal growth (Jobling et al., 1996).

Wastewater treatment plants are major contributors of EDCs into the environment. EDCs end up in wastewater as a result of natural excretion from the body or being washed off the skin. WWTPs are not designed to remove these substances. As a result, EDCs …

Tolerance Limit For Trucks With Excess Load In Transport Regulation In Indonesia, Sigit Pranowo Hadiwardoyo, Raden Jachrizal Sumabrata, Mohammed Ali Berawi

Makara Journal of Technology

Reliability of a road is mandatory since damaged will impede the traffic. Destruction is caused by various factors; one of the most important factors is excess load. Overload may give the load of each axle of a vehicle exceeds the determined standard. This condition occurs in trucks exceeding the load limit. In designing the structure of a road based on the method of Directorate General of Highways Ministry of Public Works of the Republic of Indonesia, axle load calculated in equivalent-number, or known as equivalent axle load (EAL), of 8.16 tons of standard axle. Total equivalent-number over the service life …

Earthquake Damage Intensity Relationship For Residential Houses In West Sumatra, Febrin Anas Ismail, Abdul Hakam, Fauzan Fauzan

Makara Journal of Technology

The Sumatra 30 September 2009 earthquake has damaged hundred thousand buildings in West Sumatra Province. The earthquake is located in 100 km offshore of Padang City, the Capital City of the province. Survey has been conducted to assess the damage of the building in few days after the earthquake. In this survey, the damage of buildings are categorised into 3 level that are heavily, moderate and slightly damages. This paper explores the level damage of building and then the intensity of the shaking in the affected area. Then based on the coordinate of every building location, the buildings are scattered …

Evaluation Of Universitas Indonesia’S Recharge Pond Performance And Potential Utilization For Raw Water Source, Nyoman Suwartha, Resky Agaslian Pramadin

Makara Journal of Technology

Evaluasi Kinerja Waduk Resapan UI dan Potensi Pemanfaatannya sebagai Sumber Air Baku. Waduk resapan Universitas Indonesia (UI) telah dibangun sejak 5 tahun yang lalu. Namun kegiatan monitoring dan evaluasinya sangat minim dilakukan. Tujuan dari studi ini adalah untuk mengetahui laju resapan, dan untuk mengevaluasi kondisi kuantitas dan kualitas air waduk resapan selama musim kemarau dan penghujan. Pengukuran kedalaman muka air, intensitas curah hujan dan penguapan dilakukan untuk menentukan ketersediaan air, laju resapan, dan imbangan air waduk. Sejumlah air permukaan diambil dari waduk resapan dan sungai di tiga titik sampling untuk mengetahui kondisi kualitas air eksisting. Hasil studi menunjukkan tidak ada …

Effect Of Methanol Induction And Incubation Time On Expression Of Human Erythropoietin In Methylotropic Yeast Pichia Pastoris, Adi Santoso, Neng Herawati, Yana Rubiana

Makara Journal of Technology

Erythropoietin (EPO) is a glycoprotein hormone consists of 165 amino acids and has molecular mass of 30,400 Daltons. The large quantities of these hormone required to satisfy clinical demand are currently met by recombinant expression in mammalian cell, namely chinese hamster ovary (CHO). Pichia pastoris has become popular yeast based protein production systems to substitute mammalian expression systems. P. pastoris is capable to use methanol as sole carbon and energy source. In this study, recombinant human EPO (rhEPO) protein obtained by expressing the hEPO gene in methylotropic yeast P. pastoris, strain X33. The present work was carried out to study …

Fuel Saving Strategy In Spark Ignition Engine Using Fuzzy Logic Engine Torque Control, Aris Triwiyatno, Sumardi Sumardi

Makara Journal of Technology

In the case of injection gasoline engine, or better known as spark ignition engines, an effort to improve engine performance as well as to reduce fuel consumption is a fairly complex problem. Generally, engine performance improvement efforts will lead to increase in fuel consumption. However, this problem can be solved by implementing engine torque control based on intelligent regulation such as the fuzzy logic inference system. In this study, fuzzy logic engine torque regulation is used to control the throttle position entered by the driver to achieve optimal engine torque. An engine torque vs. throttle position and engine speed mapping …

An Agri-Food Supply Chain Model To Enhance The Business Skills Of Small-Scale Farmers Using Corporate Social Responsibility, Wahyudi Sutopo, Muh. Hisjam, Yuniaristanto Yuniaristanto

Makara Journal of Technology

In general, small-scale vegetable farmers experience problems in improving the safety and quality of vegetables for supplying high-class consumers in modern retailers. Farmer Group and/or Cooperative (FGC) should be able to assist its members to meet the relevant provisions of modern retail on product specifications, delivery terms, and internal business requirements. This study proposed an agri-food supply chain (ASC) model that involves the corporate social responsibility (CSR) activities to enhance the business skills of the FGC as supplier of modern retailer. Multi-objective optimization programming is developed to determine the amount and timing of supply, level of farmers training skills, quality …

Corrosion Rate Of Carbon Steel For Flowline And Pipeline As Transmission Pipe In Natural Gas Production With Co2 Content, Andi Rustandi, Muhammad Adyutatama, Enriko Fadly, Norman Subekti

Makara Journal of Technology

The purpose of this research is to investigate the corrosion rate of carbon steel as flowline and pipeline in natural gas production with CO2 content. The influence of variety of conditions that represent the actual conditions in practice such as CO2 partial pressure and solution composition, particularly NaCl percentage were performed. Research conducted by polarization test and simulation methods using PREDICTTM software. The result of this research is used to illustrate the level of corrosion rate of typical carbon steel i.e. API 5L X-52 occurred in natural gas pipelines due to the effect of dissolved CO2. From the experiments obtained …

Modification Of Flow Structure Over A Van Model By Suction Flow Control To Reduce Aerodynamics Drag, Harinaldi Harinaldi, Budiarso Budiarso, Warjito Warjito, Engkos Achmad Kosasih, Rustan Tarakka, Sabar Pangihutan Simanungkalit, I Gusti Made Fredy Lay Teryanto

Makara Journal of Technology

Automobile aerodynamic studies are typically undertaken to improve safety and increase fuel efficiency as well as to find new innovation in automobile technology to deal with the problem of energy crisis and global warming. Some car companies have the objective to develop control solutions that enable to reduce the aerodynamic drag of vehicle and significant modification progress is still possible by reducing the mass, rolling friction or aerodynamic drag. Some flow control method provides the possibility to modify the flow separation to reduce the development of the swirling structures around the vehicle. In this study, a family van is modeled …

Age, Gender, And Muscle Strength: A Study Based On Indonesian Samples, Henny Henny, Hardianto Iridiastadi, Iftikar Zahedi Sutalaksana

Makara Journal of Technology

Age and gender have been commonly used as a main criterion in accepting a job aplicant, but it is usually not clear how these affect job performance. While a number of recent studies have been done that describe the relationships between age, gender, and participants capacity (e.g., muscle strength), the results have been inconclusive. In Indonesia, in particular, such issues have been rarely investigated, and it is still important to study the issue since the relationships between these factors are population-specific. This study aimed at describing the relationships between age and muscle strength among workers for both genders. Ninety-six male …

Circularly Polarized Microstrip Array Antenna For Ground Segment In Quasi-Zenith Satellite System, Fitri Yuli Zulkifli, Eko Tjipto Rahardjo

Makara Journal of Technology

In satellite communication system, antenna plays an important role. Therefore, the antenna must meet some requirements, such as high gain, circular polarization, and good directivity. In this paper, a four element linear array triangular patch microstrip antenna with cross slot is designed to be used for Quasi-Zenith satellite system. A simulation study as well as experimental study was carried out. The simulation showed that the 3 dB axial ratio bandwidth of 87 MHz (2.569-2.656 GHz) is achieved while the measured results showed 96 MHz (2.556-2.652 GHz). The linear array of 4 element antenna has a gain of 13.73 dB and …

Concurrent Engineering Of Tolerance Synthesis And Process Selection For Products With Multiple Quality Characteristcs Considering Process Capability, Mohamad Imron Mustajib

Makara Journal of Technology

The existences of variances that are very difficult to be removed from manufacturing processes provide significance of tolerance to the product quality characteristics target of customer functional requirement. Furthermore, quality loss incurred due to deviation of quality characteristics of the target with a specified tolerance. This article discusses the development of concurrent engineering optimization model of tolerance design and manufacturing process selection on product with multiple quality characteristics by minimizing total costs in the system, namely total manufacturing cost and quality loss cost as functions of tolerance, also rework and scrap costs. The considered multiple quality characteristics have interrelated tolerance …

Pineapple Liquid Waste As Nata De Pina Raw Material, Agus Sutanto

Makara Journal of Technology

This research aims to study the quantity, quality, ecological and economic feasibility of nata de pina production (NP) from pineapple liquid waste (PLW). The design of the study employs complete random design (CRD) with three treatments: PLW without nutrients addition (A), PLW nutrients addition (B), and PLW stored for six months with nutrients addition (C). The nata de pina’s production factors measured were weight, thickness, fiber content, color, brightness, and residual waste. The highest weight was reached in treatment B (899 grams), followed by treatment A (616.4 grams), and C (477.8 grams). The thickness of NP of the height and …

Modeling Of A New Structure Of Precision Air Conditioning System Using Secondary Condenser For Rh Regulation, Aries Subiantoro, Nasruddin Nasruddin, Feri Yusivar, Muhammad Idrus Al-Hamid, Bagio Budiardjo

Makara Journal of Technology

A dynamic mathematical model for a new structure of precision air conditioning (PAC) has been developed. The proposed PAC uses an additional secondary condenser for relative humidity regulation compared to a basic refrigeration system. The work mechanism for this system and a vapour-compression cycle process of the system are illustrated using psychrometric chart and pressure-enthalpy diagram. A non-linear system model is derived based on the conservation of mass and energy balance principles and then linearized at steady state operating point for developing a 8th-order state space model suited for multivariable controller design. The quality of linearized model is analyzed in …

Optimizing Fermentation Medium To Produce Cyclosporin A Using Response Surface Methodology, Rofiq Sunaryanto

Makara Journal of Technology

Response surface methodology (RSM) is a three factorial model which illustrates the relationship between one or more independent variables. RSM can be used to optimize the fermentation medium for the production of Cyclosporin A from the isolate Tolypocladium inflatum. The optimal point of the response surface area is predicted by using a seconddegree polynomial model and applying the statistic model obtained from the central composite design (CCD). The results of optimizing the fermentation medium for Cyclopsorin using the three independent variables of glucose, casein, and KH2PO4 show that all three of the independent variables affect the production of Cyclosporin A. …

Effects Of Adding Acid Plant Sulfur On Heap Leaching, Jibin George

Masters Theses and Doctoral Dissertations

Mining industry is heavily invested in mining various precious metals from their natural ore deposits. Copper ore deposits are found across the world and heap leaching of copper has been implemented effectively for years. The ore is broken down to copper ions and elemental sulfur in the heap. Acid plants are used in mines to replenish the raffinate leaching the heaps which consists of sulfuric acid. Molten sulfur carried in rail cars to the acid plant is often accidentally spilled on the ground. The contaminated sulfur cannot be added to the acid plant and has been disposed of as hazardous …

Development Of Strategies To Minimize The Release Of Trace Elements From Coal Waste Sources, Mohammad Rezaee

Theses and Dissertations--Mining Engineering

To assess strategies aimed at minimizing the release of trace elements and the impact of disposal of coal waste materials on the environment, two long-term leaching experiments of up to five months duration were performed using waste materials from two plants cleaning high and low sulfur bituminous coal. The tests evaluated the mobility of major trace elements under different disposal scenarios: (i) a static leaching test designed to simulate the quiescent conditions encountered by coal waste material stored under water in a stable impoundment, and (ii) a dynamic test to simulate waste materials exposed to the atmosphere, either in variable …

Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice

USF Tampa Graduate Theses and Dissertations

Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …

Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.

Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …

Effect Of Copper Addition On Mechanical Properties And Electrical Conductivity Of Pp/C-Cu Bipolar Plate Composites, Anne Zulfia, Taufik Abimanyu, Verina Warga Dalam

Makara Journal of Technology

Effect of Copper Addition on Mechanical Properties and Electrical Conductivity of PP/C-Cu Bipolar Plate Composites. Bipolar plate is a major component in PEM fuel cell which possess main function of collecting and removing electrons from anode to cathode. Therefore, materials for bipolar plates produced must have high electrical conductivity. To obtain bipolar plate materials which is cheap, lightweight and high conductivity, so it is developed bipolar plates material based on PP/C-Cu composite. PP/C-Cu composites has been made by mixing all materials then compounding, rheomix, hot blending and hot press. Cu (Copper) has been used various from 0.1 wt%, 1 wt% …

Application Of Empirical Orthogonal Function Models To Analyze Shoreline Change At Bangkalan Madura, Darius Arkwright, Suntoyo Suntoyo

Makara Journal of Technology

Bangkalan’s shoreline, especially on the opposite side of Surabaya, has been evaluated to determine the morphological changes due to wave attack, near-shore current, long-shore sediment transport and coastal configuration. This research aims to determine the dominant patterns of variation of Bangkalan’s shoreline change, expressed by Eigen-function in empirical orthogonal function (EOF) models. That was started with data collection such as oceanographic data (wave and tidal), bathymetry and topographic map and sediment data. All data was used for forecasting two-monthly shoreline. Coordinate of two-monthly shoreline was used as input of EOF model. The first Eigen mode is a profile of shoreline …

The Effectiveness Of Anaerobic Baffled Reactor And Rotating Biological Contactor In Batik Wastewater Treatment, Augustinus Ignatius Kristijanto, Widhi Handayani, Purwanti Asih Anna Levi

Makara Journal of Technology

Batik is one of popular arts of Indonesia. The batik industries in Sragen, Central Java, are prepared to compete in global market. In order to realize that objective, batik products should fulfill some qualifications, one of which is “environmental friendliness”. As batik production is usually generating wastewater which pollutes the environment, the technology of wastewater treatment should be developed to solve the problem. This preliminary study has been done to assess the effectiveness of anaerobic baffled reactor (ABR) and rotating biological contactor (RBC) in batik wastewater treatment. In 40 days of treatment period, the ABR performance in reducing pollutants showed …

Physical Characterization And Desulfurization Of Biobriquette Using Calcium-Based Adsorbent, Mahidin Mahidin, Asri Gani, Khairil Khairil

Makara Journal of Technology

Combustion of coal and co-combustion of their co-fuel contribute to gas emissions. Among the gas emissions are SOx, NOx, CO and CO2. Introduction of calcium based adsorbent is addressed to absorb SO2 that release to the atmosphere during the combustion process. Objective of the research is at first to observe the physical characteristics of biobriquettes as a function of briquette compositions (coal to palm kernel shell ratios) and Ca/S ratios (Ca in adsorbent and S in briquette) using a natural adsorbent (shellfish waste). The second objective is to investigate desulfurization characteristics as a function of Ca/S ratios and desulfurization temperatures …

Medium Density Fibreboard Made Of Acetylated Sludge From Paper Mill, Luthfi Hakim, Evalina Herawati, I Nyoman Jaya Wistara

Makara Journal of Technology

Medium Density Fibreboard Made of Acetylated Sludge from Paper Mill. Research of using sludge as raw material for making medium density fibreboard (MDF) was useful to create additional value of sludge. The objective of the research was to evaluate physical properties, mechanical properties, and durability of MDF from acetylated sludge in 4 levels of acetate anhydride (0%, 3%, 5%, and 7%) with 3 replicates. The MDF was made using dry process. After materials were mixed with adhesives, they were pressed using hotpress under 170 oC temperature and 45 Pa pressure for 25 minutes. The size of the MDF sample was …

Cassava Pulp As A Biofuel Feedstock Of An Enzymatic Hydrolysis Proces, Djuma’Ali Djuma’Ali, Nonot Soewarno, Sumarno Sumarno, Dyah Primarini, Wahono Sumaryono

Makara Journal of Technology

Cassava pulp, a low cost solid byproduct of cassava starch industry, has been proposed as a high potential ethanolic fermentation substrate due to its high residual starch level, low ash content and small particle size of the lignocellulosic fibers. As the economic feasibility depends on complete degradation of the polysaccharides to fermentable glucose, the comparative hydrolytic potential of cassava pulp by six commercial enzymes were studied. Raw cassava pulp (12% w/v, particle sizeμm) hydrolyzed by both commercial pectinolytic (1) and amylolytic (2) enzymes cocktail, yielded 70.06% DE. Hydrothermal treatment of cassava pulp enhanced its susceptibility to enzymatic cleavageas compared to …

Alos/Palsar Image Processing Using Dinsar And Log Ratio For Flood Early Detection In Jakarta Based On Land Subsidences, Dodi Sudiana, Mia Rizkinia

Makara Journal of Technology

Flood that occurred in Jakarta is not only influenced by rainfall, urban planning system and drainage alone, but also may be involved land subsidence (LS). LS is possible in because Jakarta stands on top of layers of sediments and the presence of ground water consumption in very large quantities. In this research, the Advanced Land Observing Satellite (ALOS)/Phased Array type L-band Synthetic Aperture Radar (PALSAR) data was processed to determine the level of LS in Jakarta area and its relation to flood potential area. Differential interferometry method (DInSAR) was performed on two PALSAR data with different acquisition years, i.e. 2007 …

Analytical And Computational Simulation Approaches To Design Low Energy Glass Block, Floriberta Binarti, Agustinus Djoko Istiadji, Prasasto Satwiko, Priyo Tri Iswanto

Makara Journal of Technology

Analytical and Computational Simulation Approaches to Design Low Energy Glass Block. An environmentally friendly process was developed to produce a low embodied energy glass block from waste glasses. The energy efficiency of the glass block is represented by its thermal conductance (U)

Improvement Of High Temperature Oxidation Of Low Carbon Steel Exposed To Ethanol Combustion Product At 700 °C By Hot-Dip Aluminizing Coating, Mohammad Badaruddin

Makara Journal of Technology

Low carbon steel (AISI 1005) was coated by hot-dipping into a molten Al-10% Si bath at 700 °C for 18s. After hotdipping treatment, the coating layers consisted of Al, Si, FeAl3, τ5-Fe2Al8Si, and Fe2Al5. The bare steel and the aluminized steel were isothermally oxidized at 700 °C in ethanol combustion product at atmospheric pressure for 49 h. The aluminized steel shows good performance in high temperature oxidation because the formation of Al2O3 layer on the coating surface. The growth of iron oxide nodules on the surface coating was accelerated by rapid outward diffusion of Fe-ions due to the presence of …

Establishment Code Hand Palm (Palm Code) 2d Gabor-Based Method, I Ketut Gede Darma Putra, Wira Bhuana, Erdiawan Erdiawan

Makara Journal of Technology

Establishment Code Hand Palm (Palm Code) 2D Gabor-Based Method. Palmprint is relatively new in physiological biometrics. Palmprint ROI segmentation and feature extraction are two important issues in palm print recognition. This paper introduces two steps in the center of mass moment method for ROI segmentation that will be applied in the Gabor 2D filter to obtain palm code as palmprint feature vector. Normalized Hamming distance was used to measure the similarity degrees of two feature vectors of palmprint. The system was tested using database 1000 palmprint images generated from 5 samples from each of the 200 persons randomly selected with …

Flutter Analysis Of Rx-420 Balistic Rocket Fin Involving Rigid Body Modes Of Rocket Structures, Novi Andria

Makara Journal of Technology

Flutter Analysis of RX-420 Balistic Rocket Fin Involving Rigid Body Modes of Rocket Structures. Flutter is a phenomenon that has brought a catastrophic failure to the flight vehicle structure. In this experiment, flutter was analyzed for its symmetric and antisymmetric configuration to understand the effect of rocket rigid modes to the fin flutter characteristic. This research was also expected to find out the safety level of RX-420 structure design. The analysis was performed using half rocket model. Fin structure used in this research was a fin which has semispan 600 mm, thickness 12 mm, chord root 700 mm, chord tip …