Article Per Year (5 Year)
p-Index From 2019 - 2024
0
P-Index
This Author published in this journals
All Journal Reaktor
I. G. Wenten
Unknown Affiliation
Chemical Engineering, Chemistry & Bioengineering Control & Systems Engineering Energy Materials Science & Nanotechnology

Published : 4 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 4 Documents
Search

 1 
Aktivitas Mikroba Lumpur Aktif Konsentrasi Tinggi Pada Sistem Lumpur Aktif- Membran Budiyono Budiyono; T. Setiadi; I. G. Wenten
Reaktor Volume 07 No. 1 Juni 2003
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5279.071 KB) | DOI: 10.14710/reaktor.7.1.27-32

Abstract

Pengolahan air limbah dengan sistem kombinasi proses lumpur aktif dengan membrane telah banyak dimanfaatkan di beberapa negara maju. Sistem ini diketahui mampu beroperasi dengan konsentrasi lumpur aktif (MLSS, Mixed Liquor Suspended Solid) sangat tinggi sehingga menghasilkan sistem yang  kompak dengan efisiensi pengolahan tinggi. Penelitian ini mengkaji aktifitas mikroba yang terlibat dalam sistem. Aktifitas yang dikaji antara lain laju pemanfaatan oksigen spesifik (SOUR, specific oxygen uptake rate), parameter kinetika, serta laju pemanfaatan nitrogen dan fosfor.Proses pengolahan berjalan pada konsentrasi MLSS jauh di atas proses lumpur aktif konvensional, yaitu berturut-turut 18.400, 22.900, 24.300, dan 25.500 mg/l. Untuk mendapatkan konsentrasi MLSS tersebut, proses pengolahan beroperasi pada waktu tinggal cairan (HRT, hydraulic retention yime) 24 jam dan waktu tinggal sel (SRT, solid retention time) 8, 16, 24, dan 32 hari. Hasil penelitian menunjukkan bahwa mikroorganisme yang terlibat pada proses ini ditandai oleh mikroorganisme yang mempunyai laju pertumbuhan sangat lambat. Parameter kinetika yang diperoleh sebagai berikut: laju pertumbuhan maksimum spesifik (μmax) 0,024 jam-1, koefisien perolehan sel (Y)  0,515 (mg sel/ mg COD), konstanta setengah jenuh (Ks) 589 mg/l, dan laju kematian spesifik (b) 0,010 jam-1. Dengan semakin tinggi konsentrasi lumpur aktif, maka aktifitas mikroba akan semakin kecil.  SOUR yang diperoleh untuk SRT  8,16,2 dan 32 hari berturut-turut  sebesar 0,612; 0,357; 0,279; 0,207 gO2 / (gMLSS.hari). bila ditinjau dari segi operasionalisasi unit pengolahan limbah, maka proses pengolahan lumpur aktif – membran jauh lebih menghemat kebutuhan nitrogen dan fosfor untuk nutrient.Kata kunci : aktifitas mikroba, sistem lumpur aktif-membran, SOUR
Pemekatan gliserol dengan reserve osmosis I. N. Widiasa; Wisjnuprapto Wisjnuprapto; I. G. Wenten
Reaktor Volume 6 No. 1 Juni 2002
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5531.076 KB) | DOI: 10.14710/reaktor.6.1.8-15

Abstract

Pemisahan enzim dan pemekatan produk masih menjadi kendala utama dalam aplikasi proses hidrolisis minyak/lemak secara enzimatis untuk skala industry. Dalam makalah ini akan dipaparkan kemungkinan proses reserve osmosis tekanan rendah untuk roses pemekatan larutan gliserol. Tiga tipe membrane reserve osmosis yang tersedia di pasaran dari Millipore, yakni R-15A (poliamida), R-25A (poliamida), dan R-45P (polisulfon tersulfonasi), telah digunakan. Hasil yang diperoleh menunjukkan bahwa fluks permeat meningkat secara linear terhadap tekanan operasi. Selain itu, tekanan operasi juga meningkatkan selektivitas umpan. Secara umum, membrane R-15A memberikan selektivitas yang lebih baik dibandingkan dengan membrane R-25A dan membrane R-45P, tetapi memberikan fluks yang lebih rendah. Untuk umpan dengan konsentrasi gliserol kurang dari 60.000 ppm, membrane R-25A lebih direkomendasikan karena memberikan fluks lebih dari 40% fluks air murni dan rejeksi masih di atas 85%. Prningkatan nilai Cm dan k terhadap kenaikan operasi menunjukkan bahwa kondisi percobaan masih di daerah kendali tekanan. Kata kunci : hidrolisis minyak, pemekatan gliserol, reserve osmosis
Experimental And Mathematical Modeling Studies Of Liquid-Liquid Membrane Contactor H. Susanto; I. G. Wenten
Reaktor Volume 5 No.2 Desember 2001
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (5801.676 KB) | DOI: 10.14710/reaktor.5.2.71-78

Abstract

Experimental and modeling studies of the effect of tempetarature on liquid-liquid membrane contactor (LLMC) have been done. The experiments were conducted by varying temperature of 25 up to 80 0C, cross flow velocity from 0.02 to 0.05 m/s and feed concentration of 0, 5000 and 30,000 mg/l. In these experiments microporous hydrophobic hollow fiber polypropylene membrane with 0.2 μm was used as a contacting device. The modeling has been done by compiling mathematic equation of mass and  heat transfers in liquid-liquid membrane contactor. Both the experimental and modeling result show, the increase in feed temperature increase  the flux of pure water exponentially, whereas the flux decrease with increasing the permeate temperature. The feed temperature increase at higher temperature result in hogher flux increase. The concentration of pure water result in the range of 1.8 to 5.6 mg/l depending on feed concentration.Keywords : membrane contactor, modeling
Two Dimentional Numerical Models Of Hollow Fiber Membrane Contactor N. Aryanti; Y. Bindar; I. G. Wenten
Reaktor Volume 6 No. 2 Desember 2002
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (6292.075 KB) | DOI: 10.14710/reaktor.6.2.77-84

Abstract

Membrane contactor is separation processing unit using membrane as a contacting device. The major advantage of membrane contactor relies on its high contact area compared to conventional scrubber. One of the important applications of membrane contactor is to reduce emission of acid gases. In this work, modeling of membrane contactor is conductedto describe concentration distribution along fiber length used to predict effective fiber length by solving mass conservation equation. Solving of mass conservation equation required information of fluid flow  distribution obtained by solving continuity and momentum equation simultaneously. The finite volume method is used to obtain the solution. Modeling of fluid flow was carried out by adding Darcy`s and Brinkman-Darcy flow models into Navier-Stokes equation. The momentum and continuity equation  are solved for two-dimentional cylindrical coordinate. The result of velocity profile at axial direction were validated with Pangrle et.al. (1992) experimental data. The comparison shows that consideration using Brinkman-Darcy flow model give agood agreement with experimental data in which maximal axial velocity achieved is 0,047 m/s for this model and 0,05 m/s for experimental data.the concentration profile at radial direction using Darcy and Brickman-Darcy flow models have also been investigated. Furthermore, concentration profile at axial direction using the both two flow models indicate a decrease of concentration along fiber length. The comparison between models and experimental data by Subhakti and Azmier (1997) agree very closely to the Brinkman- Darcy flow model. The prediction of effective  fiber length was conducted based on minimum economical flux oe\f membrane contactor. The calculation gives the effective fiber length obtained is 0.19 m at gas concentration, gas flow rate, and sorbent concentration of 0.02 mol/L, 0.8 m/s and 0.256 M respectively.Keywords : modeling, membrane contactor, Darcy, Brinkman-Darcy
Co-Authors Budiyono Budiyono H. Susanto I. N. Widiasa N. Aryanti T. Setiadi Wisjnuprapto Wisjnuprapto Y. Bindar