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Bandung, Indonesia

Wenten I.G.,ITB
Desalination | Year: 2016

Reverse osmosis (RO) is a pressure driven membrane process which has been widely applied and recognized as the leading technology of desalination process. Improvement in RO technology including advanced membrane material, module and process design, and energy recovery has led to cost reduction which in turn gaining interest to its commercial applications. RO is now being used in various applications including selective separation, purification, and concentration processes. In food industry, RO is applied for concentration of fruits and vegetable juices, pre-concentration of milk and whey, and dealcoholization of alcoholic beverage. For area which has large source of natural humic water or peat water, RO can be applied to produce clean water for community water supply. RO was also investigated for organic mixture separation and CO2 regeneration from essential oil extraction using supercritical fluid. The application of RO as a final step of wastewater treatment for water reuse and valuable component recovery seems to be promising in wastewater reclamation. In this paper, the applications of RO, its advantages, and limitations are discussed. In addition, challenges and perspective of RO membranes are pointed out. © 2015 Elsevier B.V.

Komalasari M.,ITB | Sunendar B.,Advance Material Processing Physics Departement Research and Applies Physical
Advanced Materials Research | Year: 2013

Nanotechnology is one of the key technology had been developed since in all fields including textile industries for medical, hygienic, and technical textiles. Particle size with nano had been indicated in particular for the application of controlled release material for functional textiles. TiO2 nano powder has remarkable photo-catalytic and semiconductor as material for various advanced technology fields of application such as UV Protection. In this research the synthesis of TiO2 nanoparticle and characterization had been conducted successfully by sol-gel method. The starch was used as a template to get nanoparticles structure. TiO2 sol with narrow particle size distribution using TiCl4 as the starting material. The sol was prepared by a process where HCl was added to a gel of hydrated titanium oxide to dissolve it. The effect of preparation parameters were investigated, by deionized water: HCl 1 M was slowly added to TiCl4 at 5 0C. In this study the production of anatase or rutile TiO2 nanostructured powder by forced hydrolysis of aqueous Ti (IV) chloride solution and concentration from 0,3, 0,5 then 1 M. TiO2 sphere were fabricated by a facile and low - cost stable starch assisted by sol-gel method. Aqueous solution of starch was added and then heated in temperature 800C and aqueous solution of ammonium hydroxide was added to adjust pH to 8. After aging period of time, the white precipitate was filtered and then calcined in temperature 5000 C. The as-obtained samples were characterize,kjnhjd by SEM (Scanning Electron Microscope), UV-vis diffuse reflectance spectroscopy, X-Ray Diffraction (XRD) and Brunauer Emmett Teller (BET) analysis. The particle size is less than 100 nm and if it uses template particle TiO2 more uniform distribution and spherical shape with particle size 170 - 200 nm. Crystalinity particle is 4 - 19 nm and the phase structure of anatase and rutile. The energy band gap semiconductor TiO2 synthesis is 3.1 to 3.7 eV. Surface area without template starch 40.655 m2/g, with total for volume 0.278 cm3/g and pore size of 27 nm, and used template starch surface area 35.488m2/g with total for volume 0.196 cm3/g and pore size of 22 nm. Based on this research, the best a crystal phase for UV protection application is rutile phase. © (2013) Trans Tech Publications, Switzerland.

Khoiruddin,ITB | Widiasa I.N.,Diponegoro University | Wenten I.G.,ITB
Journal of Food Engineering | Year: 2014

This paper reports performance of an electrodeionization (EDI) system during removal of inorganic contaminants in sugar refining process. Diluate compartments of EDI stack were filled with mixed ion-exchange resins (strong acid cation-exchange and strong base type I anion resins). Experiments were then conducted at both batch and continuous operation mode. The results showed that EDI is able to remove inorganic contaminants as well as colour body from sugar solutions. At relatively high sugar concentration, significant decrease in ions removal is observed. The increase of current density and applied voltage had little impact on ions removal and lead to current efficiency and pH reduction. The colour removal may be associated to complex bond (organic-inorganic) breakage due to water dissociation inside the diluate compartment. © 2014 Elsevier Ltd. All rights reserved.

Wenten I.G.,ITB | Khoiruddin,ITB | Arfianto F.,Badak Natural Gas Liquefaction Co. | Zudiharto,Badak Natural Gas Liquefaction Co.
Desalination | Year: 2013

In this paper, a bench scale RO/EDI system for high pressure boiler feed water is reported. Technical and economical aspects were evaluated to determine whether RO/EDI system is feasible to replace existing ion exchange bed. The EDI module used in this study was all filled electrodeionization type with mixed bed ion exchange filler. All product quality of demin water produced by RO/EDI during bench scale test shows good water quality (conductivity: 0.3-0.4μs/cm; pH: around 6.3; silica: 0.00-0.01ppm; and Na: <0.003ppm), even better than existing demin water system specification (conductivity: <5μs/cm; pH: 6.5-8.5; silica: <0.12ppm; and Na: <0.3ppm), except pH. Dissolved CO2 in water (HCO3 -) is a suspected substance which is present in RO/EDI product water that influences the pH. The specific water cost of RO/EDI was US$0.53/m3 lower than existing ion exchange beds, US$0.66/m3. The main operating costs were membrane replacement and electricity cost. Long term performance of the RO/EDI system showed stable and high product quality even during periods when the feed solution has relatively high conductivity. © 2013 Elsevier B.V.

Wayansengara I.,Bandung Institute of Technology | Mulia A.,ITB | Asrurifak M.,Research Center for Disaster Mitigation | Hutabarat D.,ITB
12th International Conference on Applications of Statistics and Probability in Civil Engineering, ICASP 2015 | Year: 2015

This paper presents recent efforts in the development of risk-targeted ground motions for the Indonesian Earthquake Resistance Building Code SNI 1726-2012. Recently, in 2010, the Indonesian seismic hazard map was revised by our Indonesian Team from the 2002 map to a new hazard map. The revised map has adopted the most recent data and current state of knowledge in probabilistic and deterministic seismic hazard assessment methodologies, and through the use of the most recent ground motion predictive equations. So-called risk-targeted ground motions (RTGM) have also been developed. The risk-targeted ground motions for Indonesia are calculated as spectral response accelerations that result in 1% probability of building collapse in 50 years through a similar methodology as conducted by Luco et al. (2007). The authors do so by adopting generic fragility curves with alogarithmic standard deviation, β, value considered to be representative of Indonesian buildings. The risk-targeted ground motions mapped for the whole of Indonesia have been developed for short and 1.0 second spectral periods. These maps have become the risk-targeted maximum considered earthquake (MCER) maps in the new SNI 1726-2012.

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