Dalam kajian ini, penapisan aliran silang yang menggunakan membran PVDF telah dilaksanakan untuk operasi permisahan sintetik air sisa minyak. Kajian ini bertujuan untuk mempelajari kesan kadar aliran dan kepekatan sintetik air sisa minyak terhadap prestasi membran yang sejajar dengan fenomena pengotoran. Tiga kepekatan iaitu 200 mg/L, 500 mg/L dan 2000 mg/L telah digunakan untuk membran penapisan yang beroperasi selama 4 jam untuk memerhatikan profil kemerosotan fluks. Bagi setiap kepekatan, membran penapisan telah masing-masing dilakukan untuk kadar aliran 0.2 LPM, 0.4 LPM dan 0.6 LPM. Ia adalah diperhatikan bahawa penapisan kek adalah mekanisme utama pengotoran yang terlibat. Dengan analisasi SEM dan FTIR yang telah dijalankan, lapisan kek adalah lebih tebal pada sistem yang beroperasi pada kepekatan tinggi dan kadar aliran rendah. Apabila kepekatan meningkat daripada 200 mg/L kepada 500 mg/L, fluks peresapan telah mengalami kemerosotan yang disebabkan oleh peningkatan rintangan kek. Sebaliknya, bagi kepekatan 2000 mg/L, rintangan keseluruhan membran telah berjaya dikurangkan oleh sebab peningkatan keliangan kek. Fenomena ini telah disebabkan oleh agregat minyak yang bersaiz lebih besar. Untuk peningkatan kadar aliran pula, prestasi membran telah dipertingkatkan dalam semua kepekatan dengan penambahbaikan fluks penyerapan dan pengurangan ketebalan lapisan kek. Taburan ketebalan lapisan kek di atas keseluruhan membran adalah tidak serata dan ianya telah dipengaruhi oleh kadar ricih yang diwujudkan dalam membran ruang. Profil had laju yang dibina oleh COMSOL telah mengesahkan kesan peningkatan kadar ricih dalam mengurangkan ketebalan lapisan kek, dan dengan itu meningkatkan fluks peresapan. Unjuran had laju telah dilaksanakan dengan bantuan COMSOL. Kadar aliran 0.89 LPM dan kadar ricih 178.40 s-1 telah dikenalpastikan sebagai magnitud minimum untuk mengurangkan fenomena pengotoran dari perspektif keseluruhan kawasan membran.
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Cross flow microfiltration (MF) of synthetic produced water using polyvinylidene fluoride (PVDF) membrane was performed in this work to study the effect of feed flow rate and synthetic produced water concentration on membrane performance which corresponded with the fouling phenomenon. Three feed concentrations of 200 ppm, 500 ppm and 2000 ppm were prepared for the MF which operated for 4 hours to observe the flux declination profile. For each of the feed concentration, the MF had been done for feed flow rate of 0.2 LPM, 0.4 LPM and 0.6 LPM, respectively. It was observed that cake filtration is the dominated fouling mechanism involved in the study. With the Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analyses done, thicker cake layer were observed on the system operated at increased feed concentration and reduced feed flow rate. With the increased concentration from 200 ppm to 500 ppm, the permeation flux had been reduced due to the increased cake resistance. In contrast, for 2000 ppm feed, the reduced overall membrane resistance was due to the improved cake porosity attributed to larger-sized oil aggregates. On the other hand, the increment of feed flow rate has enhanced the membrane performance in all feed concentrations with improved permeation flux and reduced cake layer thickness. The cake layer thickness distribution was not equal inside the membrane chamber and was highly affected by the shear stress established within the chamber. The velocity profile established via COMSOL simulation has further validated the effect of increased shear rate in reducing the cake layer thickness, and thus improving the permeate flux. Velocity projection had been done with the aids of COMSOL in identifying feed flow rate of 0.89LPM and shear rate of 178.40s-1 are minimal magnitude to alleviate the fouling phenomenon from the perspective of overall membrane effective area.
Fouling study of cross flow membrane filtration for synthetic produced water separation / Tan Jun Zhe