[Abdurahman, 2(11): November, 2013] ISSN: Impact Factor: 1.852

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1 IJESRT INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY Elucidate the Separatin Mechanisms f Cntinuus Micrave Radiatin Systems (CMWRS) Using Crude Oil Emulsins N.H.Abdurahman*1, N.H.Azharib2, Y.M.Rslic3 *1,3 Faculty f Chemical and Natural Resurces Engineering, University Malaysia Pahang 2 Faculty f Industrial Sciences and Technlgy, University Malaysia Pahang nur2000_99@yah.cm Abstract The crude il is an indispensable surce f energy. During the transprtatin, lifting and prcessing f il, ater-il emulsins are frequently created. The traditinal methds f eliminating these emulsins are based n utilizatin f high heat, chemicals, and electrical energy t frce the emulsin t separate int ater and hydrcarbn phases are disadvantages frm bth ecnmic and envirnmental perspectives. In this rk, a cntinuus micrave radiatin system as develped and applied successfully fr separatin f heavy crude il emulsins. In this study, a cntinuus micrave demulsificatin methd as utilized in a 50-50%, and 20-80% f ater-in-il emulsins ith varied micrave expsure time. Temperature prfiles f ater-in-il emulsins inside a cylindrical cntainer ere measured. The temperature rise at a given lcatin as linear. The rate f temperature increase f emulsins decreased at higher temperature due t decreasing dielectric lss f ater. Due t its fast, vlumetric, and selective heating, micrave heating can be used an alternative demulsificatin methd fr aterin-il emulsins. Keyrds: Cntinuus micrave, separatin, / emulsins, radiatin, stability, elucidate Intrductin Micraves are electrmagnetic aves ith a frequency f 300 MHz t 300 GHz, crrespnding t avelengths f 1 mm t 1 m. Beynd 30 GHz; the micrave frequency range verlaps ith the radi frequency. Because f the nature f micraves, they are gverned by the Federal Cmmunicatins Cmmissin (FCC). In Nrth America, the nly alled frequencies fr industrial use are 915, 2450, 5800 and 22,000 MHz (Dumbaugh et al, 2001). Fr use in Labratry reactins, a frequency f 2450 MHz is preferred, since this frequency has adequate penetratin depth fr mst labratry reactin cnditins. Micrave energy is receiving a cnsiderable amunt f attentin frm researchers fr a ide spectrum f applicatins (Belanger et al., 2008; Whittaker, 2009; Will et al., 2004). The fundamentally different methd f transferring energy frm the surce t the sample is the main benefit f utilizing micrave energy hen cmpared t cnventinal thermal prcessing. The crude il cntaining ater is harmful t the transprtatin, refinery, and quality f the prducts s that demulsificatin is ne f the key steps in varius sectrs f the il industry, including crude il transprtatin, petrleum refinery, as ell as il prductin. T principal appraches f demulsificatin are chemical and physical methds. The chemical methd is the additin f prper demulsifier t the emulsin and typical physical treatment techniques include heating, electrical, ultrasnic, r mechanical methd such as centrifugatin. The heating alng ith the additin f the demulsifier (thermal chemical methd) and electrical techniques are mst ppular methds, but these methds have many disadvantages: per-asting, a large additin f the demulsifier, bad ater quality, and envirnmental pllutin. Micrave has dran much mre attentin as a clean and efficient energy in recent years; many papers reprted by (Fang, et al., 1995, 1988; Xia et al., 2003; Liu et al., 2005; Chih et al., 2002; Vladana et al., 2006) have reprted the advantages f this ne technlgy after it as first tested by Klaila (1978) and Wlf (1986). Hever, the reprts abut the practical applicatin f micrave demulsificatin are very limited up t n. Materials and Methds In this study, Elba dmestic micrave ven mdel: EMO 808SS, its rated per utput is 900 atts and its peratin frequency is 2450 MHz as mdified and cnverted frm batch prcess system t a cntinuus

2 prcess and used as shn in Figures 1 and 2 respectively. Figure 1- Cntinuus micrave prcess Figure 2- Cntinuus micrave prcesses Three thermcuples type (K-IEC-584-3) ere cnnected t Pic-TC-08 data lggers, and then the thermcuples cnnected t the settling tank. The data lgger as cnnected t Pc; ith Pic Lg Rs.08.3 sftare. The thermcuples ere inserted in the settling tank t different lcatins tp, middle, and bttm f the emulsin sample t measure lcal temperatures. Sample Preparatin and Prcedures The crude il samples ere btained frm Petrnas refinery at Melaka city, 50-50%, and 20-80% ater-in-il emulsins ere prepared. Emulsins ere prepared in 900 ml graduated beakers, ith ranges by vlume f the ater and il phase. The micrave radiatin as set t different per settings. The ater phase is distilled ater. The emulsins ere agitated vigrusly using a standard three blade prpeller at speed f 2000 rpm and temperature 30 C fr 15 minutes. The cncentratins f ater in samples ere 20-50% by vlume. The vlume f ater settled t the bttm as read frm the scale n the beaker ith different times. The prepared emulsins ere used t check fr / r / emulsins. All emulsins investigated ere type f ater-in-il emulsins (il cntinuus phase). Surfactant used in this study is sdium carbnate (Na 2 CO 3 ).The sample placed in a feed tank and used a pump t pull the samples t the Elba dmestic micrave ven mdel: EMO 808SS fr radiatin. Three thermcuples ere inserted in the settling tank f emulsin sample at different lcatins, tp, middle, and bttm. The emulsin samples ere heated ith micrave radiatin fr 20, 40, 60, 80, 100, 120, 140, 160, 180, and 200 secnds. Temperature prfiles f emulsins inside a cylindrical cntainer during cntinuus micrave heating at 2450 MHz ere recrded by Pic-TC-08 data lgging. Micrave Radiatin A number f studies ere carried ut n micrave heating (MW) f il and ater systems. Micrave heating because f its vlumetric heating effects, ffers a faster prcessing rate, als micrave has anther unique feature ther than h it interacts ith matter, is its penetrating per. Micrave distributes energy ithin the bulk f mst materials, rather than just n it surface. Any heat prduced at the surface must then be cnducted r cnvicted int the material. Micrave, because the ave length is relatively lng and the methd f interactin s mild, can penetrate deeply int a substance. Penetratin energy depsitin by micrave vercmes many surfacelimiting characteristics f nrmal heating. The purpse f heating ater-in-il (/) emulsins ith micrave radiatin is t separate ater frm il. Therefre, hen ater-in-il emulsin is heated ith micrave radiatin, t phenmenns ill ccur; the first ne is the increase f temperature, hich causes reductin f viscsity and calescence. The result is separatin f ater ithut additin f chemicals (Fang, at al., 1988, 1989). Accrding t Stke s la Eq (1), if il is the cntinuus phase, the settling velcity f ater drplets is given by: 2 ( ρ ρ ) gd ν = (1) 18 µ here D is the diameter f the drplets. The viscsity f il very sensitive t temperature, as temperature increases, viscsity decreases much faster than the density difference, ( ρ ρ ) des, the result hen viscsity decreases, the drplets size increases. Therefre, micrave heating increases the velcity f ater ( ν ), and accelerates the separatin f emulsin. The higher temperature and ler viscsity make the cagulatin prcess easier. The results are larger particle

3 diameter D, and rapid separatin. Since micrave heats materials vlumetrically, it is pssible t calculate the vlume rate f micrave heat generatin frm energy balance equatin (2) as: ha Aσ 4 4 dt gmw= ( Tm Ta ) + [( Tm ) ( Ta ) ] + ρc p V V dt (2) The abve equatin assumes that the rate f heat transfer frm emulsified ater drplets t the cntinuus phase (il) is very rapid; therefre, ater and il practically have the same temperature. The right hand side f Equatin (2) cmprises f three terms, cnvective heat transfer, irradiative heat due t micrave, and cnductive heat in the sample respectively. Frm results f this study, the effect f radiative term is very small as ell as cnvective term. Since the sample cntainer (glass) has l dielectric cnstant, therefre, its heat generated assumed t be negligible. Fr calculatin f vlume rate f heat generatin in Equatin (2), the density ( ρ ), and ( C frm mixing rules Eqs. (3) & (4) as: ρ ρ φ + ρ ( 1 φ ) C m = p = Cp, φ + Cp, (1 φ) m p ) f the emulsins calculated (4) The vlume rates f micrave heat generatin f the 50-50% and 20-80% ater-in-il emulsins calculated frm temperature measurements and Equatin (2) ere shn in Tables 1 & 2 respectively. While viscsity data ere shn in Table 3. (3) Radiatin time, sec Table1. Experimental results f cntinuus micrave heating (50-50% / emulsins) (Micrave per is: 900W) Rate f Rate f Heat Dielectric Dielectric T =25.6 Temp. generatin cnstant lss C increase q T, MW tan δ = C dt/dt, r,50 50% r,50 50% cal C/sec 3 sec cm r r Table2. Experimental results f cntinuus micrave heating (20-80% / emulsins) (Micrave per is: 900W) Rate f Rate f Heat Dielectric Dielectric Radiatin T =25.6 Temp. generatin cnstant lss r time, sec C increase q T, MW tan δ = C dt/dt, cal r,20 80% r r,20 80% C/sec 3 sec cm

4 Dielectric cnstant and dielectric lss f ater used in this rk ere given by [Vn Hippel, 1954] as flls: r = T (5) r (6) = T Vn Hippel (1954) prpsed equatins fr dielectric prperties f varius petrleum ils, in this regards, dielectric cnstant and lss tangent f crude il fr this study calculated frm the equatins bel. (7) r = T tan 4 δ = (0.527T ) *10 (8) Table 3 shs viscsity data fr 50-50% and 20-80% ater-in-il emulsins respectively. Table 3: Viscsity data fr 50-50% and 20-80% / emulsins Temperature Shear rate C (sec -1 ) Viscsity (Pa.s) % / % / Shear stress (dyne/cm 2 ) Results and Discussin The micrave heating prcess as examined fr 50-50% and 20-80% f crude il emulsin samples. Transient temperature prfiles f ater-in-il emulsins during a cntinuus micrave heating ere measured. The results f calescence beteen liquid drplets f 50-50% and 20-80% ater-in-il emulsins ere shn in Figures 3 and 4 respectively. All experimental results shed that micrave radiatin is very effective in separatin f ater-in-il emulsins. Figures 3 and 4 illustrated that, micrave radiatin can raise the temperature f emulsin, reduce the viscsity, increase the velcity and accelerate separatin prcess as suggested by Equatin (1). It is fund that the sdium carbnate (Na 2 CO 3 ) as very efficient in stabilizing ater-in-il emulsins. The percent f calesced r separated ater is pltted against the time f sedimentatin. It bserved that, the 50-50% / as separated faster than 20-80% des, this may attributed due t high vlume fractin fr 50-50% ( φ = ) cmpared t 20-80%. ( φ = ). It fund that the percentage f calesced ater drplets decreases ith the cncentratin f the sdium carbnate (Na 2 CO 3 ).

5 Heating rate ( C/s) % / 20-80% / 0.2 Figure 3: Separatin f ater frm 50-50% ater-in-il emulsin Figure 4: Separatin f ater frm 20-80% ater-in-il emulsin emulsins The temperature increasing rates f irradiated samples, dielectric cnstant, dielectric lss, lss tangents, and vlume rates f heat generatin fr 50-50% and 20-80% / emulsins ere shn in Tables 1 and 2 respectively. The rate f temperature increase as calculated frm temperature increase divided by radiatin time. It is bserved that, the rate f temperature increase dt ( ) is inversely prprtinal t the increase dt in temperature T ; this as expected result since the dielectric lss f ater is small. The rates f temperature increase fr 50-50% and 20-80% / illustrated in Figure 5. Equatin (2) used t calculate the vlume rate f heat generatin, frm the calculatins; it fund that the cntributins f the heat lss by cnvective heat transfer and radiative heat lss ere very small, hile the cntributin f heat accumulatin in the emulsin is significant Temperature ( C) Figure 5: Rates f temperature increase fr 50-50% and 20-80% / emulsins In applicatin f Equatin (2) fr calculatin f vlume rates f heat generatin, the emulsin density ( ρ m ) and heat capacity ( cp m ) ere calculated frm mixture rules Equatins (3) and (4) respectively. It is bserved that, the dielectric prperties f emulsins affected by temperature in this regards, Figure 6 shs dielectric lsses fr 50-50% and 20-80% / emulsins. It is clear frm the figure, dielectric lss fr 20-80% / less than fr 50-50% this may attributed t the high temperature f 20-80% cmpared ith temperature f 50-50% /. Dielectric lss % / 50-50% / Temperature ( C) Figure 6: Dielectric lss vs. Temperatures fr 50-50% and 20-80% / emulsins The shear rate, shear stress, and viscsity f the emulsin samples ere measured ith Brkfield (DV- III) Rhemeters given in Table3. The viscsity, µ f an emulsin diminishes hen the vlume fractin f the dispersed phase φ is reduced.

6 Viscsity (Pa.s) Figure7: Viscsity vs. temperature fr 50-50% and 20-80% / emulsins Figure 7 shs the viscsity f / versus temperature, it s clear frm the Figure 7; emulsins ere very sensitive t temperature. As temperature increases, the viscsity decreases fast. The viscsities fr 50-50% and 20-80% fr / emulsins are shn in Figure 8. Increases in the internal phase vlume fractin lead t an increase in bth the viscsity and the degree f shear thinning. Viscsity (Pa.s) Figure 8: Viscsity vs. Shear rate fr 50-50% and 20-80% / emulsins Cnclusins A cntinuus micrave heating system as develped and successfully examined n crude il emulsins. This study has shn that micrave radiatin can be an effective tl t separate ater frm dispersed ater-in-il emulsins. Micrave heating prvides a ne ptin in breaking ater-in-il emulsins and enhances gravity sedimentatin t separate the emulsins int ater and il layers. Micrave separatin technlgy des nt require chemical additin. Cnsequently, it is an attractive alternative t the cnventinal methd hich smetimes requires a heavy dsage f chemicals. The temperature rise and vlume rate f heat generatin f emulsins induced by micrave radiatin can be calculated frm basic dielectric prperties. References 50-50% / 20-80% / Temperature ( C) Shear Rate (sec -1 ) 50-50% / 20-80% / [1] Belanger, R. M.; Pare, L. R. J.; Pn, O.; Fairbridge, C.; Mutyala, S. (2008). Survey f recent industrial applicatins f micrave energy. Jurnal f Micrave Per & Electrmagnetic Energy 4(4): [2] Chin-Chieh Chan; Yeng-Ching Chen. (2002). Demulsificatin f W/O emulsins by micrave radiatin. J. Separatin Science and Technlgy, 37 (15): [3] Dumbaugh, H. W.; Laless, N. W; Malmendier, W. J.; Wexell, R.D. (2001). Extractin f il frm il shale and tar sand. Canadian Patent, , Sept, [4] Fang, C. S.; Chang, B. K. L; Lai, P. M. C.; Klaila, W. J. (1988). Micrave demulsificatin. J. Chem. Eng. Cmmun., 73: [5] Fang, C. S.; Lai, P. M. C. (1995). Micrave heating and separatin f ater-in- il emulsin. Jurnal f Micrave Per and Electrmagnetic Energy. 30 (1): [6] Klaila, W. J. Micrave and apparatus fr cntrlling fluency f high viscsity hydrcarbn fluids. U. S. Patent 4,067,683, (1978) January 10. [7] Liu, X. Y.; Chu, W. H. (2005). Micrave technlgy and the experimental f demulsificatin. J. Daging Petrleum Institute, 29 (3): [8] Vladana, Rajakviic; Dejan Skala. (2006). Separatin f ater-in-il emulsins by freeze/tha methd and micrave radiatin. J. Separatin and Purificatin Technlgy, 49: [9] Vn Hippel, A.R. (1954). Dielectric Materials and Applicatins. 3 rd printing. Massachusetts Institute f Technlgy Cambridge, Massachusetts. The M.I.T. Press [10] Wlf, N. O. (1986). Use f micrave radiatin in separating emulsins and dispersins f hydrcarbns and ater. U. S Patent 4,582,629, (1986) April 15. [11] Whittaker, G. A. accessed n Jan, 29, [12] Will, H.; Schlz, P.; Ondruschka, B. (2004). Hetergeneus gas-phase catalysis under Micrave irradiatin-a ne multi-mde micrave applicatr. Tpics in Catalysis 29, 2004, [13] Xia, L. X.; Ca, G. Y.; Lu, S. W. (2003). Demulsificatin f W/O emulsins stabilized by petrleum r resin. J. Oilfield Chemistry, 20 (1):