Korean Chem. Eng. Res., Vol. 42, No. 1, February, 2004, pp. 115-120 Electric Heating * 133-791 17 * 431-711 1588-14 (2003 10 14! "#, 2003 12 20! $%) An Experimental Study for Hydrate Dissociation Phenomena and Gas Flowing Analysis by Electric Heating Method in Porous Rocks Wonmo Sung, Hoseob Lee and Hojoon Yang* Department of Geoenvironmental System Eng., Hanyang University, 17, Haengdang-dong, Sungdong-gu, Seoul 133-791, Korea *Technical Department Korea National Oil Company, 1588-14, Gwanyang-dong, Dongan-gu, Anyang, Gyonggi-do 431-711, Korea (Received 14 October 2003; accepted 20 December 2003) electric heating! "# $ % &'( )* +,-./&' 012 3 4 56789 :;<, 9 = > 56 3?;. => 56 @ => )* A %, +,-./&' B./C DEF G H IJ;. 56 K(, => +,-./&' LMN =>C +,-./O P QRS./C DEF G T. U5V W 3 4X. => )* DE Y9 IJZ K(, => [3\ T]./9 ^_ LM` ab H c' d ex. fz g=>h ab Hh ijk =>C l 8. DE i mq no pqhh rh d kst. uv, w Z./56 wx )S ab DE lp yz {D O }~ DE i'h Z d kst. Abstract In this study, an experimental apparatus has been designed and set-up to analyze the dissociating phenomena of hydrate in porous rock using electric heating method supplied at downhole. The electric heat injecting experiments have been performed to investigate the heat transfer within the core, the dissociating phenomena of hydrate, and the productivities of dissociated gas and water. These experiments were under constant heat injecting method as well as preheating methods. From the experimental results, it is seen that dissociation of hydrate is accelerated with heat. The injected heat is consumed for the dissociation and also it is lost together with outflow of the dissociated gas and water. From the investigation of gas producing behavior for various heat injecting methods, as the injected heat is greater, dissociation is accelerated faster at outlet and hence the initial gas production becomes higher. Also, it is shown that the initial gas productivity under the constant heating method is better, however, the heat is low because of smaller amount of the produced gas comparing to the amount of heat injected. In the experiments of preheating method, it was seen that gas production only initial stage is different with the preheating time, but the producing behaviors of gas production are similar. Key words: Hydrate, Formation and Dissociation Experiment, Electric Heating, Gas Production Behavior 1.. McGuire[1], Bayles [2], Kamath Godbole[3], To whom correspondence should be addressed. E-mail: wmsung@hanyang.ac.kr Selim [4]!" #$%& Verigin [5]' Yousif [6, 7]!" ()*' +,-./ 01 ()2 3456 7 8 95: ' 89;<2 345:= >? @AB' + 4CD $% [8, 9]. ()* #$%' E9 F G H IJ KL M N O PQ R S9 89T UV. W9X 4CD $% 115
116 89 YZ5[ R \] ^=G / _ `'1 Q? $%a 4CD,-. bg c d' _X 4CD / e fg O PQ dhi jkz U V. lm7 ()*' #$%2 no pqr #$% Q? 89 YZ5:X ()*G /8 89a \]s \]i2 tu5[. vwpq MxyG7 z { Tk #$% # } ~=$%R $ & 8,G ƒ s $3.& \] G7/ # ˆ \ UV. lm7 # ˆ2 Š = >? \] G =G /" # \ NŒ Œ Ž d'p. G7 =P #$%(electric heating) 2 " x,- G7 89 u } 89a / 5 y u2 ˆ Nf š, " #$% 89y ˆ 2 qn 7 #$%G lœ 89 u } \]dh2 žxÿ š. 2. / #$% ˆ NŒ 5 / bpq 1 Fig. 1G &. ˆ Nf M N PQ Q k (Fig. 2),-./ 01 ();<2 1 *" x/ ª«(sus 316) T. k/ y% } y end plugg /8, r *4a x/ X sleeveg /8 X a.?=7 sleeve ± (G /8 kg ²³Tk $%a yb k R yt1 ". ±( yb =, G µt2 Œ K1 i * " 1 95%/ kerosene { T. Fig. 2G & ¹ º +»i? ¼½P ¾U 7 =, 2 À 1 k Á t2 lm LÂ> ÃT 3 / Ä ŒT X, #$%G lœ k / 01 À 1 RTD Å7 Ä k M 2.5 cm ¼e >ŒX Fig. 1. Schematic diagram of total system. Fig. 2. Schematic diagram of coreholder. 42 1 2004 2. Æ" k ÇU/ 01 À = >? end plugg RTD Å7 N³š, y G7 =P #2 \5:= >? È 4 É%š. È/ $%#Ê } 01 45 VG7 220 VË 345[ 3(=G /8 ; a. ˆ G7 { a k /»i 1 fìp `'1 X Íx" ; Z Berea { 2 { š, Î 15.4 cm, ÏO 3.76 cm/ = X ÐÑ 24%, `'1 248.6 md.» i } 89'!G k ;G ÒÓ,0 0 Ô=G / 8 01 ka. ˆ G7 { a»i Air Products{/ 1 99.995%/ X 1 @A,. 1.5 wt%/ Õ4&Ö 2 { š. (), 01, =, ˆ '! À T Ø ŸÙ ŸÙÚÛ 5 G /8 ˆ5¼ À Tk,Na. ŸÙÚ Û 5 G À T ˆ ŸÙG 8 Ü ' 2 ˆ5š, () / OÝ Š Þª¼e 2 psiq 5 {? Ü š. ( )Ü G { a 5 01µtG 8 Ü Tk 0.25% / ß1 à. 01 áâ ã0.01 KQ ASTM X ² 0 1ä š, yêg 87 1,000 ml/revolution/ Ê G Š Þª¼e 10 ml/ wet gas meter š. =, 2-10 kω / e, UŸ å8 Ü š. 3. 3-1. #$%G /" 89 u2 ž= >8, æ, kg»i5: ˆ 2 ç' + qš. k G k èx v " ±(2 8é ê Z ëì {? = ' + í 2 î". kg 1.5 wt%/ Õ4&Ö ' @A Ô5ï ð Ä41 ñ. ˆ G7 ^= Ä41 0.71? ˆ 2 qš. ò»()ü ó È () @A $%n ô»i2 YZ5:X, ä«a $% G1 ()34 u õ r»i' öùa. ˆ 0 u G7 ˆ qt s ()34 MJ" žÿù. ( )34 øùür,»i5g eÿ!g 1/180/ ú Äû T= üýg P;< G7 () * T 89þ ü w ()/ uÿ u & ¹. Æ &/ ŸÙ =, / 3 4., ç' f" f1i x= üýg 1i Õ4&Ö Ä4Tk Ð G»iTr u P =, L a. u=/ ˆ ' 2 å8 Àa () } =, / 34 Fig. 3G & ¹ º +. Fig. 32 øùür G7 " º +»i G lm $%()Q 5.3 MPaG7 () 2.76 MPa *? ò»u G 1En2, =, 5 ŠX 17.7 kωë uÿn2.»iˆ öùtx &r / ½Y2 ~ 5ï7 Ü z Ç/»i5:X " " k bg Ív" Ä ñ= >8 annealing ' 2 ˆ5š. '»ia 895:= >8 01 279.16 KË uÿ5 ê ˆ ; <Q 273.76 K _ 7 5»i5: ' 2 2 ˆ5š. Ÿu / 1 Ý á =¼G =ê34 G /" annealing ' 2 îx s, " ' ˆ N;<2 wµ / 1 X (Yousif, 1991). 3-2. G7 =P #$%G /" 8
117 Fig. 3. Pressure and resistance behaviors during hydrate formation. 9 u } 89a / y u' \] dhi2 ž= > " ˆ 2 qš. #$% y $3/ 895ï ^= \]i2 tu5:= >" #(preheating)' «PQ #$% Q? 89 YZ5:X y1 tu d' ;{= >" «#$%(continuous heating)2 qš. # 8.8 W/ #2 10, 20, 40! $%" ê y / #k a 89() 2.4 MPa yˆ 2 qš, «#$ % 8.8 W/ #2 $%n' 5G y / #k 89y ˆ 2 qš. Æ" #$%G /" d' Ü ŸÈ fì, ž = >? #$% õ áï (G /" 89ˆ 1 qš. æ, (' #$%G /" 89y ˆ ' G7 À a ()', Ä Fig. 4-6G &. WG7 º + (G /" ˆ 5 y%/ () y / () ' vœ 9 5¼, t(fig. 4) #$%(Fig. 5, 6)G f8 áâ 2. y%/ () `'1 248.6 md Fig. 5. Pressure and resistance behaviors during hydrate dissociation under continuous heating method. Fig. 4. Pressure and resistance behaviors during hydrate dissociation under only depressurization method without injecting heat. Fig. 6. Pressure and resistance behaviors during hydrate dissociation under preheating for 10 min. kg1 í X y / ()34G w! & & K Ž Ð G»ia yby å " 2? ˆxP k/ `'1 _ u = üý. lm7 y%/ () y / ()' î/ y{" î2 & r #È 89a Ž ¾U s u= $' #$% ()*Ü 89 %9 Zq 2. Æ" «#$%' #2 fì8ür, «#$% # G f8 Ü &œ 5¼G y () y%/ ()G '½n2. «#$%/ y% ()34 (' #G /" ()34 E9 eè KX «PQ #$%G /8 7 7È n2. Fig. 4-6G7, 34 øùür,, ( ^=Ü Ž2 89T = üý. #$%G /" 0134 Çu2 ž= >? y / # KX(²)5 ) v #Ê2 ä«$%? À a k/ òí0 Korean Chem. Eng. Res., Vol. 42, No. 1, February, 2004
118 q" OÝG 294.1 K 3 K 1 â 1. #$% y 1 \]a / \]G /" «PQ # ˆ \= üý. #$%G /" 89a / \]i2 ž= >? «#$%RG /" 10, 20, 40! #" ê ( ˆ, #$%õ (RG /" 89y ˆ 2 qš,?=7 À a \]Ê2 Fig. 8-12G 15š. (G /" \]Ê 3423Q Fig. 8 øùür, \]^= 45 Ë k/ Ð2 "L yt 4 89 G lm `'i 5X ü 89a y 2. «#$%G /" \]Ê 3423 Q Fig. 9 øùür, #$% Q8 89 Y ZTk \]^= ytx «PQ #$% Q? 89 / yi2 tu5ï \] 5 ê 200 Ë œ 2 G f8 \]Ê 62. #2 10, 20 Fig. 7. The comparison of the core temperatures between the closed system and continuous heating system. 1 «#$%G /" 89yˆ M À a k / òí01 Fig. 7G &. k / òí01 À = >? #$%G7 5.1 cm 10.3 cm jkz V(Fig. 2/ 2, 3 * RTD Å7)G7 À a 01 ]+òíš. Fig. 7G & ¹ º + ^=G ²)5 ' «#$% ˆ, OÝ, #$ % Q? 01 eè uÿn2. ê 89y ˆ 2 q" «#$%/ OÝ $%a # \]a G / 8 Ts7 ²)5 G f8 k/ òí01 77È ~ +L-2..È \]^=G 89G a #' 89 X #' no eè &/& Q8 ^= 01Ü š 5 ~ Çu & 02 ß Q. Æ" #$% Q? #$% ò»u G 1E 01 ²)5 / OÝG 297.1 KQ w8 89y ˆ 2 Fig. 9. Gas production continuous heating method. Fig. 8. Gas production under depressureization method. 42 1 2004 2 Fig. 10. Gas production under preheating for 40 min.
119 Fig. 11. Gas production under preheating for 20 min. Fig. 13. Comparison of gas recoveries for different heating methods. Fig. 12. Gas production under preheating for 10 min., 40 " ê (G /" 89y ˆ 5 À a \]Ê 3423Q Fig. 10G7 Fig. 12 øùür, {G $% a #G /8 y / 01 uÿ? 89TX ü 89a ˆ ^= \] 2, #5¼ Î ^= \]Ê 62..È 40! #2 " OÝ Q Fig. 10 \]^=G \]Ê 10 ' 20 #" OÝG f8 7 4-98& X \] 5 ê 200 &r7 \] î/ #Ù 2. #$% Q8 k/ 01 uÿts7 î/ 89Tk vw Ä4a kg7/ yˆ ' y{ " Çu2 & 92. \]Ê/ 232 fì? & : Fig. 132 øùür, 40! #" OÝ ^=G N z Ç/ \]TX Šö;P\]Ê N & 1. { </ kg7 ˆ qtk & ¹ =v d'7 G7 " º + 89y ˆ G $%a #G /8 k/ b01 Fig. 14. Comparison of water recoveries for different heating methods. uÿ? 89T = üý. «#$%G /8 À a \]Ê2 øùür, ^= \]Ê R Šö;P \]Ê ç2. $%a #ÊG f8 \ ]a / Ç L GH dhi _ç2 / ". lm7 «#$% $%a # 89 k/ 01 uÿ5: T=1 R k $3 T # zl dhi jk-2. Æ" #G7 #2 10 ' 20 " OÝ fì8ür # 5¼ âg /8 ^= \]ÊR â >? bpq ;P\]Ê y{" Çu2 & 92. ˆ q G $%a #Ê/ âg /8 y G ƒ / 89 1G lm `'1 Ems ^= \]ÊG7R â >? ê/ y () âg /8 \= üý. no \]a / ;P\]Ê Fig. 14G &. Fig. 14 øùür, «#$% " OÝ # " OÝÜ ^=/ \] Korean Chem. Eng. Res., Vol. 42, No. 1, February, 2004
120 Table 1. The comparison of energy efficiencies for different heating methods Heating Method 100 min 500 min 1,000 min Output (kj) Energy efficiency Output (kj) Energy efficiency Output (kj) Energy efficiency Continuous heating 25.71 0.49 52.39 0.20 52.39 0.10 Preheating for 10 min 9.78 1.85 46.69 8.84 59.70 11.31 Preheating for 20 min 16.89 1.60 56.22 5.32 67.81 6.42 Preheating for 40 min 56.82 2.69 68.70 3.25 75.65 3.58 No heating 9.21 48.38 53.01 Ê @ Ž2, «PQ #$% Q" 01uÿ / Vi1? y1 tut = üý. Æ", # " OÝ fì8ür 40! #" OÝ #! 89Tk \? \]^=G / \]Ê 62. G7 =P #$%2 ",- G7 / #E u' G lœ 89 u2 ˆ Nf Ͻ ä }?»i' =P #$ %G /" 89ˆ 2 q? ç' + $A2 ñ2. (1) #$%G /" 89y ˆ G7 À a ()3 4 232 ž" $', #$%2 " OÝ y%/ ()' y / ( ) +L 9 5¼ $%a # z OÝv Ž & 1. kg ƒ 89T P J 2 / Ž #$%G /8 89 YZ 2. (2) #$%G /" 0134 ž" $', «#$%G /" 8 9y 5 89G /" #?R LBm y T G /8 $%a # ˆT Ž2, \]^=G $%a # $ 89G Tk k/ 01 T Ž À T. (3) #$%G lœ \]i2 ž" $', #2 $%ng lm ^=/ \]Ê ~T,.È ^=G $%a #Ê C y D/ 89 YZ5ï7 ^=/ \]i ~ 2. ;P\]Ê2 fì" $', «#$% ^= \ ]i ÇER $%a #ÊG f8 \]T / Ç L G H dhi _ç2 $%a # k $3 T Ç z= üý. (4) #G /" 89ˆ 5, #5¼G lm \]Ê ^= GR â >? bpq \]î y{" Çu2 & 92. #G /8 y G7 89T 1G lm ^=/ \]GR â >? ê/ y () âg /87R \T= üý. (5) #$%G /" 89y ˆ G7 \]a / Ç «#$ %G /" OÝ N z \]a Ž & 1, «PQ #$% Q? / 01 uÿ G lm / y1 ~ š= üý. Fý 2001G1 "HC+ZI U/ ðg /? T J B(KRF-2001-041-E00507). 1. McGuire, P. L., Recovery of Gas from Hydrate Deposits using Conventional Technology, paper SPE/DOE 10832 presented at the Unconventional Gas Recovery Symposium, Pittsburgh, PA, May, 373-387 (1982). 2. Bayles, G. A., Sawyer, W. K., Anada, H. R., Reddy, S. and Malone, R. D., A Steam Cyclic Model for Gas Production from a Hydrate Reservoir, Chem. Eng. Comm., 47(2), 225-245(1986). 3. Kamath, V. A. and Godbole, S. P., Evaluation of Hot Brine Stimulation Technique for Gas Production From Natural Gas Hydrates, JPT, 39(11), 1379-1388(1987). 4. Selim, M. S. and Sloan, E. D., 1990, Hydrate Dissociation in Sediment, SPERE, May, 245-251(1990). 5. Verigin, N. N., Khabibullin, I. L. and Khalikov, G. V., Linear Problem of the Dissociation of the Hydrates of Gas in a Porous Medium, Izvest. Akad. Nauk. SSR, Mekhanika Zhidkosti Gaza, 1. 174-177(1980). 6. Yousif, M. H., Li, P. M., Selim, M. S. and Sloan, E. D., Depressurization of Natural Gas Hydrate in Berea Sandstone Cores, J. Inclusion Phenomena & Molecular Recognition Chem., 8, 71-88(1990). 7. Yousif, M. H., Abass, H., Selim, M. S. and Sloan, E. D., Experimental and Theoretical Investigation of Methane-Gas-Hydrate Dissociation in Porous Media, SPERE, Feb., 69-76(1991). 8. Sung, W. M., Lee H. S., Kim, S. J. and Kang, H., Experimental Investigation of Production behaviors of Methane Hydrate Saturated in Porous Rock, Energy Sources, 25(8), 845-856(2003). 9. Seo, Y. T., Kang, S. P. and Lee, H., Experimental Determination and Thermodynamic Modeling of Methane and Nitrogen Hydrates in the Presence of THF, Propylene Oxide, 1,4-Dioxane and Acetone, Fluid Phase Equilibria, 189(1-2), 99-110(2001). 42 1 2004 2