scholarly journals Membran Separasi Serat Berongga untuk Hemodialisis

2019 ◽  
Vol 7 (1) ◽  
pp. 27-36
Author(s):  
Krisna Lumban Raja
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Salt Water ◽  
Cross Flow ◽  
Polymer Chains ◽  
Current Status ◽  
Separation Membranes ◽  
Fiber Separation ◽  
Dead End ◽  
Wide Range

Polimer mempunyai aplikasi luas. Campuran heterogennya membentuk struktur fasa terpisah menjadi membran untuk membuat perangkat medis. Fungsi membran melakukan penghalangan selektif dengan aspek keragaman : tebal, struktur, diameter pori, muatan listrik, perpindahan partikel. Grup. Membran separasi adalah membran sintetis untuk pemisahan. Membuat membran separasi polimerik dibutuhkan kriteria polimer berdaya rekat rendah, berdaya tahan pembersihan tinggi, berkarakteristik rantai polimer saling cocok, harga murah, serta mudah diperoleh. Sifat kimia permukaan membran memberi konsekuensi pembasahan atau pencemaran yang mempengaruhi daya tahan membran. Konfigurasi membran separasi adalah silang aliran dan dead-end.Hukum Darcy merumuskan pemodelan yang pokok pada membran separasi dead end. Serat membran morfologinya keropos dan gaya pendorongnya perbedaan konsentrasi. Aliran nya silang dan modulnya menampung hingga 10.000 serat berdiameter 200 μm sampai 2500 μm. Pada dialisis, aliran darah dan dialisat berlawanan, agar pengeluaran zat-zat beracun maksimal. Aplikasi membran serat berongga untuk hemodialisis karena gagal ginjal kronis. Hakekat dialisis adalah memindahkan zat-zat racun dari metabolisme dan memperbaiki keseimbangan garam, air dan asam dalam darah. Status iptek terkini membran hemodialisis adalah pada ginjal buatan dari bahan hidup selain peralatan hemodialisis yang dapat berpindah-pindah, dibawa, dikenakan di badan, dan ditanam dalam tubuh.Kata kunci : Membran, Sintetis, Separasi, Hemodialisis, Serat berongga.AbstractPolymers have a wide range of uses. Their heterogenous blends form separated phase structures to become membranes for making medical devices. Membranes serve as selective barriers with various classifications such as thickness, structure, pore diameter, electric charged, particle transport, and in groups. A separation membrane is synthetically created for separation purpose. To make polymeric separation membranes require polymers that are low binding affinity, withstand the harsh cleaning conditions, suitable with properties of polymer chains, reasonable pricing, and easily obtainable. Two flow configurations of separation membranes are cross flow and dead-end filtrations. Darcy’s law formulates the main modeling equation for the dead end filtration. Hollow fiber separation membranes have porous morphology and driving force of concentration gradients. They have cross flows and their modules can contain up to 10.000 fibers ranging from 200 to 2500 μm in diameter. In dialysis, blood travels in the opposite direction with the dialysate to maximize the excretion of poisonous substances. A hollow fiber membrane application is for hemodialysis of chronic renal failure that causes physiological derangements. Actually dialysis is to remove toxic end-products of nitrogen metabolism and improve the balance of the salt, water, and acid-base derangements in blood. The current status of hemodialysis are the bio-artificial kidneys along with the development of mobile, portable, wearable and implantable hemodialysis devices.Keywords : Membrane, Synthetic, Separation, Hemodialysis, Hollow-fiber.

A New Short–Cut Design Method for Ultrafiltration and Hyperfiltration Cross–Flow Hollow Fiber Membrane Modules

2012 ◽  
Author(s):  
Wan Ramli Wan Daud
Keyword(s):  
Hollow Fiber ◽  
Driving Force ◽  
Hollow Fiber Membrane ◽  
Cross Flow ◽  
Extinction Curve ◽  
Membrane Area ◽  
Transfer Unit ◽  
Dead End ◽  
The Dead ◽  
The Difference

Although ultrafiltration and hyperfiltration have replaced many liquid phase separation equipment, both are still considered as “non–unit operation” processes because the sizing of both equipments could not be calculated using either the equilibrium stage, or the rate–based methods. Previous design methods using the dead–end and complete–mixing models are unsatisfactory because the dead–end model tends to underestimate the membrane area, due to the use of the feed concentration in the driving force, while the complete–mixing model tends to overestimate the membrane area, due to the use of a more concentrated rejection concentration in the driving force. In this paper, cross–flow models for both ultrafiltration and hyperfiltration are developed by considering mass balance at a differential element of the cross–flow module, and then integrating the expression over the whole module to get the module length. Since the modeling is rated–based, the length of both modules could be expressed as the product of the height of a transfer unit (HTU), and the number of transfer unit (NTU). The solution of the integral representing the NTU of ultrafiltration is found to be the difference between two exponential integrals (Ei(x)) while that representing the NTU of hyperfiltration is found to be the difference between two hypergeometric functions. The poles of both solutions represent the flux extinction curves of ultrafiltration and hyperfiltration. The NTU for ultrafiltration is found to depend on three parameters: the rejection R, the recovery S, and the dimensionless gel concentration Cg. For any given Cg and R, the recovery, S, is limited by the corresponding flux extinction curve. The NTU for hyperfiltration is found to depend on four parameters: the rejection R, the recovery S, the polarization β, and the dimensionless applied pressure difference ψ. For any given ψ and R, the recovery, S, is limited by the corresponding flux extinction curve. The NTU for both ultrafiltration and hyperfiltration is found to be generally small and less than unity but increases rapidly to infinity near the poles due to flux extinction. Polarization is found to increase the NTU and hence the length and membrane area of the hollow fiber module for hyperfiltration. Key words: Ultrafiltration; hyperfiltration; reverse osmosis; hollow fiber module design; crossflow model; number of transfer unit; height of a transfer unit

Drinking water production by coagulation-microfiltration and adsorption-ultrafiltration

1998 ◽  
Vol 37 (10) ◽  
pp. 135-146 ◽  
Author(s):  
Akira Yuasa
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Hollow Fiber ◽  
Cross Flow ◽  
Ceramic Membranes ◽  
Cellulose Acetate Membrane ◽  
Water Recovery ◽  
Dead End ◽  
Iron Manganese ◽  
Gac Adsorption

Microfiltration (MF) and ultrafiltration (UF) pilot plants were operated to produce drinking water from surface water from 1992 to 1996. Microfiltration was combined with pre-coagulation by polyaluminium chloride and was operated in a dead-end mode using hollow fiber polypropylene and monolith type ceramic membranes. Ultrafiltration pilot was operated in both cross-flow and dead-end modes using hollow fiber cellulose acetate membrane and was combined occasionally with powdered activated carbon (PAC) and granular activated carbon (GAC) adsorption. Turbidity in the raw water varied in the range between 1 and 100 mg/L (as standard Kaolin) and was removed almost completely in all MF and UF pilot plants to less than 0.1 mg/L. MF and UF removed metals such as iron, manganese and aluminium well. The background organics in the river water measured as KMnO4 demand varied in the range between 3 and 16 mg/L. KMnO4 demand decreased to less than 2 mg/L and to less than 3 mg/L on the average by the coagulation-MF process and the sole UF process, respectively. Combination of PAC or GAC adsorption with UF resulted in an increased removal of the background organics and the trihalomethanes formation potential as well as the micropollutants such as pesticides. Filtration flux was controlled in the range between 1.5 and 2.5 m/day with the trans-membrane pressure less than 100 kPa in most cases for MF and UF. The average water recovery varied from 99 to 85%.

Desalination with a cascade of cross-flow hollow fiber membrane distillation devices integrated with a heat exchanger

AIChE Journal ◽  
2010 ◽  
Vol 57 (7) ◽  
pp. 1780-1795 ◽  
Author(s):  
Hanyong Lee ◽  
Fei He ◽  
Liming Song ◽  
Jack Gilron ◽  
Kamalesh K. Sirkar
Keyword(s):  
Heat Exchanger ◽  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Cross Flow ◽  
Membrane Distillation ◽  
Fiber Membrane

Steady three-dimensional flows past hollow fiber membrane arrays – cross flow arrangement

2018 ◽  
Vol 96 (12) ◽  
pp. 1272-1287 ◽  
Author(s):  
Mustafa Usta ◽  
Michael Morabito ◽  
Mohammed Alrehili ◽  
Alaa Hakim ◽  
Alparslan Oztekin
Keyword(s):  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Flow Behavior ◽  
Membrane Surface ◽  
Three Dimensional ◽  
Cross Flow ◽  
Coefficient Of Performance ◽  
Fiber Membrane ◽  
Cfd Simulations ◽  
Flow Configuration

Hollow fiber membrane (HFM) modules are among the most common separation devices employed in membrane separation applications. Three-dimensional steady-state computational fluid dynamics (CFD) simulations are carried out to study flow past hollow fiber membrane banks (HFMB). The current study investigates the effects of flow behavior on membrane performance during binary mixture separations. Carbon dioxide (CO2) removal from methane (CH4) is examined for various arrangements of HFMs in staggered and inline configurations. The common HFM module arrangement is the axial flow configuration. However, this work focuses on the radial cross-flow configuration. The HFM surface is a functional boundary where the suction rate and concentration of each species are coupled and are functions of the local partial pressures, the permeability, and the selectivity of the HFM. CFD simulations employed the turbulent k–ω shear stress transport (SST) model to study HFM performance for Reynolds numbers, 200 ≤ Re ≤ 1000. The efficiency of the inline and staggered arrangements in the separation module is evaluated by the coefficient of performance and the rate of mass flow per unit area of CO2 passing across the membrane surface. This work demonstrates that the module with staggered arrangement outperforms the module with the inline arrangement.

Sign in / Sign up

Export Citation Format

Share Document