13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model,...

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æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘  ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ 1  ÿ‡∑’¬π  –π—¬ 2 ™≠“πÿ™ · ß«‘‡™’¬√ 3 ·≈– ¬ÿ∑∏π“ Ø‘√–«≥‘™¬å°ÿ≈ 4 Abstract Tirawanichakul, S. 1 , Sanai, S. 1 , Sangwichien, C. 1 and Tirawanicahkul, Y. 2 Parameters for the analysis of natural rubber drying Songklanakarin J. Sci. Technol., May 2007, Suppl 2 : 335-346 The purpose of this research was to study and develop a mathematical model of essential parameters affecting drying process in terms of equilibrium moisture content (EMC), apparent density, percentage of void fraction, specific heat capacity and effective diffusion coefficient (D) for three kinds of natural rubber. Three raw natural rubber samples in this work used crumb rubber, rubber stick and rubber sheet with an initial moisture content ranging between 30 and 45% wet-basis that were normally used for producing the standardized Thai rubber (STR) block rubber and air dried rubber sheet (ADS). The results show that the apparent density and specific heat of all natural rubber samples were linearly dependent on the moisture content whilst the percentage of void fraction of natural rubber was inversely related to moisture content. The isotherm EMC equations formulated by the Herderson model for the crumb rubber and rubber stick were the best fitting with the experimental values, and for the rubber sheet. The isotherm EMC equation using the Halsey model was the most appropriable to the experimental results. In addition, the effective diffusion coefficients of all natural rubber materials, which were the function of drying temperature and π‘æπ∏åµâπ©∫—∫ 1 Department of Chemical Engineering, Faculty of Engineering, 2 Department of Physics, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90112 Thailand. 1 ª√.¥. (‡∑§‚π‚≈¬’æ≈—ßß“π) ºŸâ™à«¬»“ µ√“®“√¬å 2 π—°»÷°…“ª√‘≠≠“‚∑À≈—° Ÿµ√ «».¡.  “¢“«‘»«°√√¡‡§¡’ 3 Ph.D. (Chemical Engineering) ºŸâ™à«¬»“ µ√“®“√¬å ¿“§«‘™“«‘»«°√√¡‡§¡’ §≥–«‘»«°√√¡»“ µ√å 4 ª√.¥. (‡∑§‚π‚≈¬’æ≈—ßß“π) ºŸâ™à«¬»“ µ√“®“√¬å ¿“§«‘™“øî ‘° å §≥–«‘∑¬“»“ µ√å ¡À“«‘∑¬“≈—¬ ß¢≈“π§√‘π∑√å Õ”‡¿ÕÀ“¥„À≠à ®—ßÀ«—¥ ß¢≈“ 90112 Corresponding e-mail : [email protected] √—∫µâπ©∫—∫ 21 ‡¡…“¬π 2549 √—∫≈ßæ‘¡æå 27 °—𬓬π 2549

Transcript of 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model,...

Page 1: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈1 ÿ‡∑’¬π –π—¬

2 ™≠“πÿ™ · ß«‘‡™’¬√

3

·≈– ¬ÿ∑∏π“ Ø‘√–«≥‘™¬å°ÿ≈4

AbstractTirawanichakul, S.1, Sanai, S.1, Sangwichien, C.1 and Tirawanicahkul, Y.2

Parameters for the analysis of natural rubber dryingSongklanakarin J. Sci. Technol., May 2007, Suppl 2 : 335-346

The purpose of this research was to study and develop a mathematical model of essential parameters

affecting drying process in terms of equilibrium moisture content (EMC), apparent density, percentage of

void fraction, specific heat capacity and effective diffusion coefficient (D) for three kinds of natural rubber.

Three raw natural rubber samples in this work used crumb rubber, rubber stick and rubber sheet with an

initial moisture content ranging between 30 and 45% wet-basis that were normally used for producing the

standardized Thai rubber (STR) block rubber and air dried rubber sheet (ADS). The results show that the

apparent density and specific heat of all natural rubber samples were linearly dependent on the moisture

content whilst the percentage of void fraction of natural rubber was inversely related to moisture content.

The isotherm EMC equations formulated by the Herderson model for the crumb rubber and rubber stick

were the best fitting with the experimental values, and for the rubber sheet. The isotherm EMC equation

using the Halsey model was the most appropriable to the experimental results. In addition, the effective

diffusion coefficients of all natural rubber materials, which were the function of drying temperature and

π‘æπ∏åµâπ©∫—∫

1Department of Chemical Engineering, Faculty of Engineering, 2Department of Physics, Faculty of Science,

Prince of Songkla University, Hat Yai, Songkhla, 90112 Thailand.

1ª√.¥. (‡∑§‚π‚≈¬’æ≈—ßß“π) ºŸâ™à«¬»“ µ√“®“√¬å

2π—°»÷°…“ª√‘≠≠“‚∑À≈—° Ÿµ√ «».¡. “¢“«‘»«°√√¡‡§¡’

3Ph.D. (Chemical

Engineering) ºŸâ™à«¬»“ µ√“®“√¬å ¿“§«‘™“«‘»«°√√¡‡§¡’ §≥–«‘»«°√√¡»“ µ√å 4ª√.¥. (‡∑§‚π‚≈¬’æ≈—ßß“π) ºŸâ™à«¬»“ µ√“®“√¬å

¿“§«‘™“øî ‘° å §≥–«‘∑¬“»“ µ√å ¡À“«‘∑¬“≈—¬ ߢ≈“π§√‘π∑√å Õ”‡¿ÕÀ“¥„À≠à ®—ßÀ«—¥ ߢ≈“ 90112

Corresponding e-mail : [email protected]

√—∫µâπ©∫—∫ 21 ‡¡…“¬π 2549 √—∫≈ßæ‘¡æå 27 °—𬓬π 2549

Page 2: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 336

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

drying time, were in range of 10-6-10-7 m2/hr. However, prediction of the evolution of moisture content of

thin-layer drying under the condition of drying temperatures of 40-70oC (rubber stick and rubber sheet) and

100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying

temperature and drying time.

Key words : effective diffusion coefficient, equilibrium moisture content, mathematical model,natural rubber

∫∑§—¥¬àÕ

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ÿ‡∑’¬π –π—¬ ™≠“πÿ™ · ß«‘‡™’¬√ ·≈– ¬ÿ∑∏π“ Ø‘√–«≥‘™¬å°ÿ≈

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‰¥â·°à §à“§«“¡™◊Èπ ¡¥ÿ≈ §à“§«“¡Àπ“·πàπª√“°Ø ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“» §à“§«“¡√âÕπ®”‡æ“– ·≈–§à“

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‡Õ ∑’Õ“√凰√¥µà“ßÊ ®“°º≈°“√∑¥≈Õß æ∫«à“ §à“§«“¡Àπ“·πàπª√“°Ø·≈–§«“¡√âÕπ®”‡æ“–¢Õ߬“ß∑—Èß 3 ·∫∫

¡’§à“‡æ‘Ë¡¢÷Èπµ“¡§«“¡™◊Èπ‡√‘Ë¡µâπ„π≈—°…≥–‡™‘߇ âπ √âÕ¬≈–™àÕß«à“ߢÕßÕ“°“»·ª√º°º—π°—∫§à“§«“¡™◊Èπ¢Õ߬“ß ·≈–

¡°“√§«“¡™◊Èπ ¡¥ÿ≈‰Õ‚´‡∑Õ¡ ”À√—∫‡»…¬“ß°âÕπ·≈–¬“߇ âπ „π√Ÿª·∫∫ ¡°“√¢Õß Henderson ·≈–¬“ß·ºàπ

§◊Õ ¡°“√¢Õß Halsey “¡“√∂Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’∑’Ë ÿ¥ πÕ°®“°π’Èæ∫«à“§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√ଗߺ≈¢Õß

¬“ß∑—Èß 3 ™π‘¥ ¡’§à“Õ¬Ÿà„π™à«ß 10-6-10

-7 m

2/hr ‚¥¬‡ªìπøíß°å™—π°—∫Õÿ≥À¿Ÿ¡‘∑’Ë„™â„π°“√Õ∫·Àâß ·≈–°“√‡ª≈’ˬπ·ª≈ß

§«“¡™◊Èπ¢Õß°“√Õ∫·Àâß™—Èπ∫“ߢÕ߬“ß∑—Èß 3 ™π‘¥ „π™à«ßÕÿ≥À¿Ÿ¡‘ 40-130oC (¬“߇ âπ·≈–¬“ß·ºàπ) ·≈–™à«ß

Õÿ≥À¿Ÿ¡‘ 100-130oC (‡»…¬“ß°âÕπ) “¡“√∂Õ∏‘∫“¬‰¥â¥â«¬ ¡°“√Õ∫·Àâß·∫∫‡Õ¡æ‘√‘§—≈´÷Ë߇ªìπøíß°å™—π°—∫Õÿ≥À¿Ÿ¡‘

·≈–‡«≈“∑’Ë„™â„π°“√Õ∫·Àâß

¬“ßæ“√“∏√√¡™“µ‘‡ªìπº≈‘µ¿—≥±å®“°∏√√¡™“µ‘ ¬“ßæ“√“®—¥‡ªìπæ◊™‰√à‡»√…∞°‘®∑’Ë ”§—≠Õ—π¥—∫Àπ÷ËߢÕߪ√–‡∑»‰∑¬ ‚¥¬ª√–‡∑»‰∑¬‡ªìπºŸâ àßÕÕ°¬“ßæ“√“√“¬„À≠à∑’Ë ÿ¥„πªï 2546 ¡’æ◊Èπ∑’˪≈Ÿ°¬“ß 12.5 ≈â“π‰√à ¡’º≈º≈‘µ¬“ߪ√–¡“≥ 2.90 ≈â“πµ—π (°√¡«‘™“°“√‡°…µ√, 2547) ¥—ßπ—Èπ®÷ß¡’§«“¡®”‡ªìπ®–µâÕß¡’°“√æ—≤π“»—°¬¿“æ¥â“π°“√º≈‘µ·≈–ß“π«‘®—¬æ◊Èπ∞“π¥â“π¬“ßæ“√“Õ¬à“ßµàÕ‡π◊ËÕß‚¥¬¡’‡ªÑ“À¡“¬À≈—° §◊Õ °“√‡æ‘Ë¡º≈º≈‘µ¬“ßæ“√“·≈–§«∫§ÿ¡§ÿ≥¿“欓ߢÕߪ√–‡∑»„Àâ Õ¥§≈âÕß°—∫Õÿª ߧå¢ÕߺŸâ∫√‘‚¿§∑—Ë«‚≈° ·≈– “¡“√∂·¢àߢ—π„πµ≈“¥µà“ߪ√–‡∑»‰¥â º≈‘µ¿—≥±å¬“ßæ“√“∑’Ë¡’°“√ àßÕÕ° ‰¥â·°à ¬“ß·ºàπ√¡§«—π ¬“ß·∑àß¡“µ√∞“π‡Õ ∑’Õ“√å (Standardized Thai Rubber, STR) ·≈–πÈ”¬“ߢâπ‡ªìπµâπ

¬“ß∏√√¡™“µ‘ “¡“√∂π”¡“„™â‰¥â∑—Èß„π√Ÿª¢ÕßπÈ”¬“ß

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Page 3: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

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Cousin ·≈–§≥– (1993) ‰¥â∑”°“√»÷°…“°“√Õ∫·Àâ߇»…¬“ß∏√√¡™“µ‘ (Natural Crumb Rubber) æ∫«à“™à«ß

°“√Õ∫·Àâß¡’ 3 ™à«ß ™à«ß·√°™—Èπ¬“ß®–Õ‘Ë¡µ—«¥â«¬πÈ” Õÿ≥À¿Ÿ¡‘¢ÕßÕ“°“»·≈–‡¡Á¥¬“ß®–‡∑à“°—∫Õÿ≥À¿Ÿ¡‘¢Õß°√–‡ª“–‡ªï¬°„π™à«ß∑’Ë 2 ‡°‘¥°“√Õ∫·Àâß·∫∫Õ—µ√“§ß∑’Ë (constant rate)Õÿ≥À¿Ÿ¡‘ §«“¡™◊Èπ —¡æ—∑∏å¢ÕßÕ“°“»·≈–ª√‘¡“≥πÈ”„π¬“ß≈¥≈ßÕ¬à“ß√«¥‡√Á« ™à«ß∑’Ë 3 ®–‡ªìπ™à«ßÕ—µ√“Õ∫·Àâß≈¥≈ß(Falling rate)

Naon ·≈–§≥– (1993) ∑”°“√∑¥≈ÕßÕ∫·Àâ߬“ß∏√√¡™“µ‘·≈–æ—≤π“·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å‡æ◊ËÕÀ“ ¿“«–∑’ˇÀ¡“– ¡ ”À√—∫Õ∫·Àâ߬“ß∏√√¡™“µ‘ ‚¥¬„™â‡§√◊ËÕßÕ∫·Àâß¢π“¥ 3x1x2 ≈∫.‡¡µ√ §«“¡‡√Á«≈¡ 0-5 ‡¡µ√/«‘π“∑’Õÿ≥À¿Ÿ¡‘Õ“°“» 20-150oC §«“¡™◊Èπ —¡æ—∑∏å 0-100% ®“°º≈°“√∑¥≈Õß æ∫«à“ Õ—µ√“°“√Õ∫·Àâß®–¢÷ÈπÕ¬Ÿà°—∫Õÿ≥À¿Ÿ¡‘‡«≈“°“√Õ∫·Àâß ·≈–§à“§«“¡™◊Èπ —¡æ—∑∏å §à“ —¡ª√– ‘∑∏‘Ï°“√∂à“¬‚Õ𧫓¡√âÕπ (h) ®–¢÷ÈπÕ¬Ÿà°—∫Õÿ≥À¿Ÿ¡‘¢Õß«— ¥ÿ·≈–Õÿ≥À¿Ÿ¡‘¢ÕßÕ“°“»‡¡◊ËÕ‰¥â§à“æ“√“¡‘‡µÕ√åµà“ßÊ ®“°°“√Õ∫·Àâß™—Èπ∫“ß ·≈–π”§à“æ“√“¡‘‡µÕ√å‡À≈à“π—Èπ‰ª∑”π“¬Õ—µ√“°“√Õ∫·Àâß™—ÈπÀπ“¥â«¬·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å æ∫«à“º≈®“°·∫∫®”≈Õß„°≈⇧’¬ß°—∫º≈°“√∑¥≈Õß ‚¥¬°”À𥧫“¡™◊Èπ ÿ¥∑⓬À≈—ß°“√Õ∫·Àâ߇∑à“°—∫ 0.8% ·≈–®“°°“√π”·∫∫®”≈Õ߉ª„™â‡ª√’¬∫‡∑’¬∫‡§√◊ËÕßÕ∫·Àâß Trolley ·∫∫°÷ËßÕ—µ‚π¡—µ‘∑’Ë„™â„πÕÿµ “À°√√¡æ∫«à“„Àâº≈„°≈⇧’¬ß°—π∑—Èߥâ“𧫓¡™◊Èπ Õÿ≥À¿Ÿ¡‘ §«“¡™◊Èπ —¡æ—∑∏å ·≈–æ≈—ßß“π∑’Ë„™â„π°“√Õ∫·Àâß

∏π‘µ ·≈–§≥– (2542) ‰¥â»÷°…“·≈–À“·π«∑“ß°“√Õ∫·Àâß∑’ˇÀ¡“– ¡¢Õ߇¡≈Á¥„π¡–¡à«ßÀ‘¡æ“πµå·∫∫∂“¥À¡ÿπ‚¥¬ √â“߇§√◊ËÕßÕ∫·Àâ߇¡≈Á¥„π‡¡≈Á¥¡–¡à«ßÀ‘¡æ“πµå·∫∫∂“¥À¡ÿπ·≈–æ—≤π“·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å º≈°“√‡ª√’¬∫‡∑’¬∫°“√∑¥≈Õß·≈–·∫∫®”≈Õß æ∫«à“ ·∫∫®”≈Õß “¡“√∂∑”𓬰“√Õ∫·Àâ߉¥â¥’ ‚¥¬∑’ËÕ—µ√“°“√Õ∫·Àâß®–„°≈⇧’¬ß°—∫°“√∑¥≈Õß ·≈–„π°“√Õ∫·Àâߧ«√§”π÷ß∂÷ߧÿ≥¿“æ¢Õߺ≈‘µ¿—≥±å ‡«≈“∑’Ë„™â„π°“√Õ∫·Àâß·≈–æ≈—ßß“π∑’Ë„™â„π°“√Õ∫·Àâß

Wetchacama ·≈–§≥– (2002) ‰¥â∑”°“√»÷°…“À“·∫∫®”≈Õßæ“√“¡‘‡µÕ√åÕ∫·ÀâߢÕß¡–¡à«ß·™àÕ‘Ë¡ æ∫«à“§«“¡™◊Èπ ¡¥ÿ≈≈¥≈ßµ“¡Õÿ≥À¿Ÿ¡‘ ¡°“√¢Õß BET (1938)Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’∑’Ë ÿ¥ º≈°“√∑¥≈ÕßÕ∫·Àâß¡–¡à«ß·™àÕ‘Ë¡· ¥ß„Àâ‡ÀÁπ«à“ —¡ª√– ‘∑∏‘Ï°“√·æ√à‡æ‘Ë¡¢÷Èπµ“¡Õÿ≥À¿Ÿ¡‘¢Õß°“√Õ∫·Àâß §«“¡Àπ“·πàπ≈¥≈ßµ“¡§«“¡™◊Èπ‡√‘Ë¡µâπ

Page 4: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 338

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

·≈–§«“¡√âÕπ®”‡æ“–‡æ‘Ë¡¢÷Èπµ“¡ª√‘¡“≥§«“¡™◊Èπ‡√‘Ë¡µâπ¥â«¬Tabatabaee ·≈–§≥– (2004) ‰¥â∑”°“√»÷°…“°“√

Õ∫·Àâß™—Èπ∫“ß·≈–≈—°…≥–‡©æ“–¢Õß°“√ rewetting ‡¡≈Á¥¢â“« “≈’ æ∫«à“ ¡°“√¢Õß Page (1949) “¡“√∂Õ∏‘∫“¬°“√Õ∫·Àâß™—Èπ∫“ß·≈–°“√ rewetting ¢â“«‰¥â¥’∑’Ë ÿ¥

Tirawanichakul ·≈– Tirawanichakul (2004)‰¥â»÷°…“ª√‘¡“≥§«“¡™◊Èπ ¡¥ÿ≈¢Õ߇»…¬“ß´÷Ë߇ªìπ«—µ∂ÿ¥‘∫„π°“√º≈‘µ¬“ß·∑àß‡Õ ∑’Õ“√å ¿“¬„µâ ¿“«–§ß∑’Ë∑’ËÕÿ≥À¿Ÿ¡‘ 35-60oC §«“¡™◊Èπ —¡æ—∑∏å 10-90% ®“°º≈°“√∑¥≈Õ߉¥âπ” ¡°“√À“§à“§«“¡™◊Èπ ¡¥ÿ≈ 4 ¡°“√ ∑”°“√‡ª√’¬∫‡∑’¬∫‚¥¬æ‘®“√≥“§à“§«“¡·ª√ª√«π 2 µ—« §◊Õ SSE (sum ofsquares error) ·≈– SD (Standard deviation) æ∫«à“ ¡°“√¢Õß Halsey (1948) ‡ªìπ ¡°“√∑’ˇÀ¡“– ¡∑’Ë ÿ¥∑’Ë®–„™â„π°“√∑”π“¬§à“§«“¡™◊Èπ ¡¥ÿ≈¢Õ߬“ß ´÷Ëßæ∫«à“°“√§“¬§«“¡™◊Èπ¢Õ߬“ß —¡æ—π∏å°—∫Õÿ≥À¿Ÿ¡‘·«¥≈âÕ¡∑’˧«“¡™◊Èπ —¡æ—∑∏å§ß∑’Ë πÕ°®“°π’Ȭ—ßæ∫«à“Õ—µ√“°“√Õ∫·Àâߢ÷Èπ°—∫√–¬–‡«≈“·≈–Õÿ≥À¿Ÿ¡‘Õ∫·Àâß

®“°º≈ß“π«‘®—¬∑’Ë°≈à“«¡“¢â“ßµâπ √ÿª‰¥â«à“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ‰¥â·°à §à“§«“¡™◊Èπ ¡¥ÿ≈ §à“§«“¡Àπ“·πàπª√“°Ø‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“» §à“§«“¡√âÕπ®”‡æ“– ·≈–§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√৫“¡™◊È𠇪ìπµâ𠇪ìπæ“√“¡‘‡µÕ√å∑’Ë„™â ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâß ‡æ◊ËÕ„™â»÷°…“À“·π«∑“ß°“√Õ∫·Àâß∑’ˇÀ¡“– ¡∑—Èß„π¥â“πæ≈—ßß“π §ÿ≥¿“æ∑—Èß∑“ß°“¬¿“æ·≈–∑“߇§¡’ ”À√—∫º≈‘µ¿—≥±åπ—ÈπÊ ‰¥â¥’ Õ¬à“߉√°Áµ“¡°“√»÷°…“À“æ“√“¡‘‡µÕ√åæ◊Èπ∞“π ”À√—∫°“√Õ∫·Àâ߬“߇™à𠇻…¬“ß°âÕπ ¬“ß·ºàπ¥‘∫ √«¡∑—Èߺ≈‘µ¿—≥±å¬“ß∏√√¡™“µ‘‡™à𠬓ß∂⫬ ¬“߇ âπ ‡À≈à“π’Ȭ—߉¡à¡’√“¬ß“π‰«â ¥—ßπ—Èπß“π«‘®—¬π’È®÷ß¡’«—µ∂ÿª√– ߧå‡æ◊ËÕ»÷°…“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘ ‰¥â·°à §à“§«“¡™◊Èπ ¡¥ÿ≈§à“§«“¡Àπ“·πàπª√“°Ø ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“» §à“§«“¡√âÕπ®”‡æ“– ·≈–§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√à ·≈–æ—≤π“·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å¢Õß ¡°“√Õ∫·Àâß™—Èπ∫“ß ”À√—∫¬“ß·µà≈–™π‘¥ ‡æ◊ËÕ„™âÀ“·π«∑“ß°“√Õ∫·Àâß∑’ˇÀ¡“– ¡¿“¬„µâ ¿“«–¢ÕßÕ“°“»·«¥≈âÕ¡Àπ÷ËßÊ µàÕ‰ª

«‘∏’°“√«‘®—¬

·∫àßÕÕ°‡ªìπ¢—ÈπµÕπ ¥—ßπ’È

1. °“√‡µ√’¬¡§«“¡™◊Èπ∑’Ë„™â„π°“√∑¥≈Õß

¬“ß∏√√¡™“µ‘∑’Ëπ”¡“∑¥≈Õß ‰¥â·°à ‡»…¬“ß°âÕπ ¬“ß·ºàπ ¬“ß‡ âπ µ—¥‡ªìπ™‘Èπ‡≈Á°Ê „Àâ¡’¢π“¥„°≈⇧’¬ß°—∫‚√ßß“ππ”¡“‡µ√’¬¡§«“¡™◊Èπ¢Õ߬“ß‚¥¬°“√æàπ≈–ÕÕßπÈ” ‡°Á∫‰«â„π¿“™π–ªî¥ ·™à§â“ߧ◊π‰«â 1-2 «—π ‡æ◊ËÕ„À≥⧫“¡™◊Èπª√–¡“≥20-65% ¡“µ√∞“π·Àâß ·≈â«®÷ßπ”ÕÕ°¡“∑¥≈Õß

°àÕπ∑”°“√∑¥≈Õßπ”¡“À“§«“¡™◊Èπµ“¡¡“µ√∞“π¢Õß AOAC (1995)

2. °“√∑¥≈ÕßÀ“§«“¡™◊Èπ ¡¥ÿ≈·∫∫§“¬§«“¡™◊Èπ

𔇻…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ ª√–¡“≥ 30-50 °√—¡ ‰ª∫√√®ÿ„πµ–·°√ß√Ÿª∑√ß°√–∫Õ° ·≈â«π”‰ª·¢«π‰«â„π¢«¥ ∫√√®ÿ “√≈–≈“¬‡°≈◊ÕÕ‘Ë¡µ—«µà“ßÊ §◊Õ LiCl, NaCl,KNO

3, MgCl

2.6H

2O, Mg(NO

3)2.6H

2O, (NH

4)2.SO

4

ªî¥Ω“¢«¥„Àâ·πàπ ∑”Õ¬à“ß≈– 2 ¢«¥ ‚¥¬µâÕß√–«—߉¡à„Àâ “√≈–≈“¬‡°≈◊Õ —¡º— °—∫µ–·°√ß ªî¥Ω“¢«¥„Àâ·πàπ π‘∑𔉪„ à„πµŸâÕ∫´÷Ëߧ«∫§ÿ¡Õÿ≥À¿Ÿ¡‘‰¥â ‚¥¬„™âÕÿ≥À¿Ÿ¡‘ 30oC‡ªìπ‡«≈“ 10-30 «—π ‡æ◊ËÕ√Õ„Àâ√–∫∫‡¢â“ Ÿà ¡¥ÿ≈∑“ߧ«“¡™◊Èπ√–À«à“߬“ß°—∫ “√≈–≈“¬‡°≈◊ÕÕ‘Ë¡µ—« ·≈â«®÷ß𔉪À“§à“§«“¡™◊Èπ ¡¥ÿ≈ À≈—ß®“°π—Èπ∑”°“√∑¥≈Õ߇™àπ‡¥‘¡·µà‡ª≈’ˬπÕÿ≥À¿Ÿ¡‘‡ªìπ 35, 40, 45, 50, 55 ·≈– 60oC µ“¡≈”¥—∫

3. °“√À“§«“¡Àπ“·πàπª√“°Ø

∑¥≈Õß‚¥¬π”µ—«Õ¬à“ß∑’ˇµ√’¬¡‰¥â®“°À—«¢âÕ 1 ∑’褈Ҥ«“¡™◊Èπµà“ßÊ ¡“„ à„π¿“™π–√Ÿª∑√ß°√–∫Õ°∑’Ë¡’ª√‘¡“µ√250 ≈∫.´¡. ‚¥¬§àÕ¬Ê „ à®π‡µÁ¡¿“™π– ·≈â«π”‰ª™—ËßπÈ”Àπ—° ·≈–§”π«≥À“§«“¡Àπ“·πàπª√“°Ø‡©≈’ˬ¢Õß·µà≈–§à“§«“¡™◊Èπ¢Õßµ—«Õ¬à“ß ·≈–∑”°“√∑¥≈Õß´È”∑’Ë·µà≈–§«“¡™◊Èπ 3 §√—Èß

§”π«≥§à“§«“¡Àπ“·πàπª√“°Øµ“¡ ¡°“√ (1)

ρ = mVb

(1)

‡¡◊ËÕ ρ §◊Õ §«“¡Àπ“·πàπª√“°Ø¢Õߢ⓫‡ª≈◊Õ°,°°./≈∫.‡¡µ√

m §◊Õ §«“¡™◊Èπ‡√‘Ë¡µâπ¢Õߢ⓫‡ª≈◊Õ°,% ¡“µ√∞“π·Àâß

Vb§◊Õ ª√‘¡“µ√¿“™π–, ≈∫.‡¡µ√

Page 5: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

«. ߢ≈“π§√‘π∑√å «∑∑.

ªï∑’Ë 29 (©∫—∫摇»… 2) æ.§. 2550 : ∫—≥±‘µ»÷°…“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ·≈–§≥–339

4. °“√À“√âÕ¬≈–™àÕß«à“ߢÕßÕ“°“»

π”µ—«Õ¬à“ß∑’ˇµ√’¬¡‰¥â®“°À—«¢âÕ 1 ∑’褈Ҥ«“¡™◊Èπµà“ßÊ¡“„ à„π¿“™π–√Ÿª∑√ß°√–∫Õ°∑’Ë¡’ª√‘¡“µ√ 250 ≈∫.´¡.‚¥¬§àÕ¬Ê „ à®π‡µÁ¡¿“™π–·≈–‡µ‘¡πÈ”≈ß„π¿“™π–®π‡µÁ¡∫—π∑÷°ª√‘¡“µ√πÈ”∑’Ë„™â‰ª ·≈–∑”°“√∑¥≈Õ߇™àπ‡¥’¬«°—ππ’È°—∫µ—«Õ¬à“߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ ∑ÿ°Ê §à“§«“¡™◊Èπ∑’ˇµ√’¬¡‰«â„π¢âÕ 1 ·≈â«π”º≈∑’ˉ¥â§”π«≥À“√âÕ¬≈–™àÕß«à“ߢÕßÕ“°“» ·≈–∑”°“√∑¥≈Õß´È”∑’Ë·µà≈–§«“¡™◊Èπ 3§√—Èß

§”π«≥§à“√âÕ¬≈–™àÕß«à“ߢÕßÕ“°“»µ“¡ ¡°“√ (2)

ε = VOil

Vb

×100 (2)

‡¡◊ËÕε §◊Õ §à“ —¥ à«π™àÕß«à“ߢÕßÕ“°“», %V

oil§◊Õ ª√‘¡“µ√πÈ”¡—π, ≈∫.‡¡µ√

Vb

§◊Õ ª√‘¡“µ√¿“™π–, ≈∫.‡¡µ√

5. °“√∑¥≈ÕßÀ“§à“§«“¡√âÕπ®”‡æ“–

𔇻…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ ®“°¢âÕ 1 π”¡“À“πÈ”Àπ—°·Àâß ·≈–„ ൗ«Õ¬à“ß≈ß„π·§≈Õ√’¡‘‡µÕ√å∑’Ë∑√“∫πÈ”Àπ—°·πàπÕπ ·≈–„™âπÈ”°≈—ËπÕÿ≥À¿Ÿ¡‘‡√‘Ë¡µâπ 65oC πÈ”Àπ—°40 °√—¡ „ à≈߉ª„π·§≈Õ√’¡‘‡µÕ√å ªî¥Ω“ °«π„À⇢⓰—π„À⥒ —߇°µ§à“Õÿ≥À¿Ÿ¡‘∑’Ë®ÿ¥ ¡¥ÿ≈ ∫—π∑÷°º≈ ·≈–∑”°“√∑¥≈Õß´È”∑’Ë·µà≈–§«“¡™◊Èπ 3 §√—Èß

∑”°“√§”π«≥À“§à“§«“¡√âÕπ®”‡æ“–¥â«¬ ¡°“√∑’Ë (3)

cp = −[mccc (Teq − Tci ) + mwcw (Teq − Twi )]

mp (Teq − Tpi )(3)

‡¡◊ËÕ cp

§◊Õ §«“¡√âÕπ®”‡æ“–¢Õߢ⓫‡ª≈◊Õ°, kJ/kgoCcc

§◊Õ §à“§«“¡®ÿ§«“¡√âÕπ®”‡æ“–¢Õß·§≈Õ√’¡‘‡µÕ√å,kJ/kgoC

cw

§◊Õ §à“§«“¡®ÿ§«“¡√âÕπ®”‡æ“–¢ÕßπÈ”, kJ/kgoCm

c§◊Õ ¡«≈¢Õß·§≈Õ√’¡‘‡µÕ√å, °°.

mp§◊Õ ¡«≈¢Õß«— ¥ÿ, °°.

mw§◊Õ ¡«≈¢ÕßπÈ”, °°.

Teq

§◊Õ Õÿ≥À¿Ÿ¡‘∑’Ë ¿“«– ¡¥ÿ≈, oC

Tci

§◊Õ Õÿ≥À¿Ÿ¡‘¢Õß·§≈Õ√’¡‘‡µÕ√å∑’Ë ¿“«–‡√‘Ë¡µâπ,oC

Twi

§◊Õ Õÿ≥À¿Ÿ¡‘¢ÕßπÈ”∑’Ë ¿“«–‡√‘Ë¡µâπ, oCT

pi§◊Õ Õÿ≥À¿Ÿ¡‘¢Õß«— ¥ÿ∑’Ë ¿“«–‡√‘Ë¡µâπ, oC

6. °“√∑¥≈ÕßÕ∫·Àâß™—Èπ∫“ß

∑”°“√∑¥≈ÕßÕ∫·Àâßµ—«Õ¬à“ß∑’ˇµ√’¬¡§«“¡™◊Èπ‰«â„π¢âÕ 1 ¡“∑¥≈ÕßÕ∫·Àâߥ⫬Õÿª°√≥åÕ∫·Àâß∑’Ëæ—≤π“‚¥¬ ÿ¿«√√≥ ·≈–§≥– (2537) §«“¡™◊Èπ‡√‘Ë¡µâπ¢Õßµ—«Õ¬à“ßÕ¬Ÿà„π™à«ß 30-65% ¡“µ√∞“π·Àâß ”À√—∫‡»…¬“ß°âÕπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 100-130oC §«“¡‡√Á«≈¡ 1.5-2.5 ‡¡µ√/«‘π“∑’ ·≈– ”À√—∫¬“ß·ºàπ ¬“ß‡ âπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 40-70oC §«“¡‡√Á«≈¡ 1.5-2 ‡¡µ√/«‘π“∑’ ¢âÕ¡Ÿ≈∑’˵âÕß∫—π∑÷°§◊Õ πÈ”Àπ—°¢Õßµ—«Õ¬à“ßæ√âÕ¡µ–·°√ßÕ∫·Àâß Õÿ≥À¿Ÿ¡‘Õ“°“»√âÕπ Õÿ≥À¿Ÿ¡‘Õ“°“»·«¥≈âÕ¡°√–‡ª“–‡ªï¬° ·≈–°√–‡ª“–·Àâß ∫—π∑÷°º≈°“√∑¥≈Õß∑ÿ°Ê 5 π“∑’ „π™—Ë«‚¡ß·√° ∑ÿ° 10 π“∑’ „π§√÷Ëß™—Ë«‚¡ß∂—¥‰ª ·≈–∑ÿ°§√÷Ëß™—Ë«‚¡ß„π™—Ë«‚¡ßµàÕÊ ‰ª ®π°√–∑—Ë߉¥â§à“§«“¡™◊Èπ ÿ¥∑⓬ª√–¡“≥4% ¡“µ√∞“π·Àâß ®÷ßÀ¬ÿ¥°“√∑¥≈Õß

∑ƒ…Æ’

§«“¡™◊Èπ ¡¥ÿ≈ §◊Õ ‡¡◊ËÕπ”‡Õ“«— ¥ÿ∑’Ë¡’‚§√ß √â“ß¿“¬„π‡ªìπ√Ÿæ√ÿ𠇙àπ π”‡¡≈Á¥æ◊™‰ª«“߉«â„πÕ“°“» «— ¥ÿπ—ÈπÕ“®®–§“¬ (desorption) §«“¡™◊Èπ„Àâ°—∫Õ“°“» À√◊Õ¥Ÿ¥´—∫(adsorption) §«“¡™◊Èπ®“°Õ“°“» ·≈–‡¡◊ËÕ«“߉«â‡ªìπ‡«≈“π“πÊ «— ¥ÿπ’È®–¡’§«“¡™◊Èπ§ß∑’˧à“Àπ÷Ë߇√’¬°«à“§«“¡™◊Èπ ¡¥ÿ≈(Equilibrium Moisture Content, EMC) √Ÿª·∫∫ ¡°“√§«“¡™◊Èπ ¡¥ÿ≈∑’ˇ≈◊Õ°„™â‡æ◊ËÕÕ∏‘∫“¬§«“¡™◊Èπ ¡¥ÿ≈¢Õß«— ¥ÿ „π™à«ß§«“¡™◊Èπ —¡æ—∑∏å 0-100% ∑’ËÕÿ≥À¿Ÿ¡‘µà“ßÊ ”À√—∫„πß“π«‘®—¬π’È¡’¥—ßπ’È

¡°“√¢Õß Chung and Pfost (1967)

ln RH = (A

RTabs

)exp(−BMeq ) (4)

¡°“√¢Õß Henderson (1952)

1− RH = exp(−ATabs MeqB ) (5)

Page 6: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 340

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

¡°“√¢Õß Halsey (1948)

RH = exp(−A

RTabs

Meq )B(6)

‡¡◊ËÕ A, B, C, D §◊Õ §à“§ßµ—«„π ¡°“√ ´÷Ëߢ÷Èπ°—∫Õÿ≥À¿Ÿ¡‘·≈–™π‘¥¢Õß«— ¥ÿ

Meq

§◊Õ §«“¡™◊Èπ ¡¥ÿ≈, ‡»… à«π À√◊Õ% ¡“µ√∞“π·Àâß

R §◊Õ §à“§ßµ—«¢Õß°ä“´ ‡∑à“°—∫ 8.314kJ/kmol-K

RH §◊Õ §«“¡™◊Èπ —¡æ—∑∏å¢ÕßÕ“°“»,‡»… à«π

Tabs

§◊Õ Õÿ≥À¿Ÿ¡‘ —¡∫Ÿ√≥å, K

¡°“√Õ∫·Àâß §◊Õ ¡°“√∑’ËÕ“®‡¢’¬π¢÷Èπ‚¥¬„™â∑ƒ…Æ’À√◊Õº≈°“√∑¥≈ÕßÀ√◊Õ∑—Èß ÕßÕ¬à“ߪ√–°Õ∫°—π ‡æ◊ËÕπ”¡“„™â∑”π“¬Õ—µ√“°“√Õ∫·Àâßµ≈Õ¥®π∂÷ߺ≈¢Õßµ—«·ª√µà“ßÊ ∑’Ë¡’º≈µàÕ°“√Õ∫·Àâߺ≈‘µ¿—≥±åπ—ÈπÊ ¡°“√Õ∫·Àâß∑’Ëπ‘¬¡„™â°—π ‰¥â·°à ¡°“√Õ∫·Àâß∑“ß∑ƒ…Æ’ (Theoreticaldrying equation) ¡°“√Õ∫·Àâß°÷Ëß∑ƒ…Æ’ ·≈– ¡°“√Õ∫·Àâß·∫∫‡Õ¡æ‘√‘§—≈

¡°“√Õ∫·Àâß∑“ß∑ƒ…Æ’ ®–æ‘®“√≥“ Õß√Ÿª∑√ߧ◊Õæ‘®“√≥“‡ªìπ√Ÿª∑√ß°≈¡·≈–·ºàπ·∫π°«â“ß ‚¥¬®–„™â‡æ’¬ß “¡‡∑Õ¡·√°¢Õß ¡°“√°“√Õ∫·Àâß ¥—ßπ’È

√Ÿª∑√ß°≈¡

MR = 6π 2

exp−π 2 Dt

r02

+ 14

exp

−4π 2 Dtr0

2

+ 19

exp

−9π 2 Dtr0

2

(7)√Ÿª∑√ß·ºàπ·∫π°«â“ß

MR = 8π 2

exp−π 2 Dt

12

+ 19

exp

−9π 2 Dt12

+ 125

exp

−25π 2 Dt12

(8)‡¡◊ËÕ r

0§◊Õ √—»¡’¢Õ߬“ß∑¥≈Õß = 0.0025 ‡¡µ√

l §◊Õ §«“¡Àπ“§√÷ËßÀπ÷ËߢÕ߬“ß∑¥≈Õß =0.00325 ‡¡µ√

D §◊Õ §à“ —¡ª√– ‘∑∏‘Ï°“√·æ√ଗߺ≈, µ√.‡¡µ√/™¡.

MR §◊Õ Õ—µ√“ à«π§«“¡™◊Èπ, ‰√âÀπ૬ ‡¢’¬π‡ªì𧫓¡ —¡æ—π∏å√–À«à“ߧ«“¡™◊Èπ‰¥â«à“

MR =M − Meq

Min − Meq

‡¡◊ËÕ M §◊Õ §«“¡™◊Èπ„π°“√∑¥≈Õß, ‡»… à«π¡“µ√∞“π·Àâß

Min

§◊Õ §«“¡™◊Èπ‡√‘Ë¡µâπ, ‡»… à«π¡“µ√∞“π·ÀâßM

eq§◊Õ §«“¡™◊Èπ ¡¥ÿ≈, ‡»… à«π¡“µ√∞“π·Àâß

¡°“√Õ∫·Àâß°÷Ëß∑ƒ…Æ’ (Semi-theoretical dryingequation)

¡°“√∑’Ëπ‘¬¡„™â°—π¡’√Ÿª·∫∫¥—ßπ’È§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√à (D) ·≈–§à“§ßµ—«¢Õß°“√Õ∫

·Àâß (k) ‡ªìπ§à“§ß∑’Ë¢Õß ¡°“√·µà≈– ¡°“√¥—ß°≈à“«®–‡ªìπ ¡∫—µ‘‡©æ“–¢Õߺ≈‘µ¿—≥±åÀπ÷ËßÊ ¿“¬„π™à«ß ¿“«–Õ“°“»Õ∫·Àâß∑’Ë∑”°“√∑¥≈Õ߇∑à“π—È𠧫“¡ —¡æ—π∏å¢Õß§à“§ß∑’ËÕ∫·Àâßπ’È¡—°π‘¬¡„™â ¡°“√Õ“√å√’‡π’¬ ‡™àπ‡¥’¬«°—∫§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√ଗߺ≈ ¥—ßµàÕ‰ªπ’È

MR = exp(−kt)

‡¡◊ËÕ A ·≈– B §◊Õ §à“§ßµ—«¢Õß ¡°“√, ¢÷ÈπÕ¬Ÿà°—∫™π‘¥¢Õߺ≈‘µ¿—≥±å

k §◊Õ §à“§ßµ—«¢Õß ¡°“√, s-1

Tabs

§◊Õ Õÿ≥À¿Ÿ¡‘Õ∫·Àâß, K

¡°“√Õ∫·Àâ߇աæ‘√‘§—≈ (Empirical drying equa-tion)

¡°“√Õ∫·Àâ߇աæ‘√‘§—≈ §◊Õ ¡°“√∑’Ë √â“ß®“°¢âÕ¡Ÿ≈°“√∑¥≈Õß ”À√—∫º≈‘µ¿—≥±å „π™à«ßÕÿ≥À¿Ÿ¡‘™à«ß§«“¡™◊Èπ —¡æ—∑∏å ·≈–§«“¡‡√Á«¢ÕßÕ“°“»Õ∫·ÀâßÀπ÷ËßÊ æ∫«à“ “¡“√∂„™â∑”π“¬Õ—µ√“°“√Õ∫·Àâ߉¥â¥’ ·µà¡’¢âÕ®”°—¥„π‡ß◊ËÕπ‰¢°“√Õ∫·Àâß∑’˵âÕß°“√µâÕßµ√ß°—∫ ¿“«–°“√∑¥≈Õß

”À√—∫„πß“π«‘®—¬π’È ®“°º≈°“√∑¥≈ÕßÕ∫·Àâß™—Èπ∫“ß “¡“√∂π”¢âÕ¡Ÿ≈°“√∑¥≈Õ߉ª √â“ߧ«“¡ —¡æ—π∏å„π‡™‘ß§≥‘µ»“ µ√å„π√Ÿª·∫∫ ¡°“√Õ∫·Àâß°÷Ëß∑ƒ…Æ’ ·≈– ¡°“√Õ∫·Àâ߇աæ‘√‘§—≈

Page 7: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

«. ߢ≈“π§√‘π∑√å «∑∑.

ªï∑’Ë 29 (©∫—∫摇»… 2) æ.§. 2550 : ∫—≥±‘µ»÷°…“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ·≈–§≥–341

º≈°“√∑¥≈Õß·≈–«‘®“√≥å

1. °“√À“§«“¡™◊Èπ ¡¥ÿ≈·∫∫§“¬§«“¡™◊Èπ

®“°º≈°“√∑¥≈ÕßÀ“§«“¡™◊Èπ ¡¥ÿ≈¢Õ߇»…¬“ß°âÕπ„π™à«ßÕÿ≥À¿Ÿ¡‘ 30-60C ·≈–°“√‡¢’¬π‚ª√·°√¡«‘‡§√“–Àå ¡°“√∂¥∂Õ¬‚¥¬«‘∏’°”≈—ß ÕßπâÕ¬∑’Ë ÿ¥ ‚¥¬„™â√Ÿª·∫∫ ¡°“√§«“¡™◊Èπ ¡¥ÿ≈¢Õß Henderson (1952) ¡°“√Halsey (1948) ¡°“√¢Õß Chung ·≈– Pfost (1967)·≈– ¡°“√¥—¥·ª≈ߢÕß Kaleemullah (1952) º≈∑’ˉ¥âπ”· ¥ß‰«â„π√“¬ß“ππ’È ®–‡ª√’¬∫‡∑’¬∫√Ÿª·∫∫ ¡°“√§«“¡ ¡¥ÿ≈ 3 √Ÿª·∫∫ ¡°“√∑’Ë„°≈⇧’¬ß‡∑à“π—Èπ

®“°°“√∑¥≈Õ߇¡◊ËÕπ”¢âÕ¡Ÿ≈¡“À“§à“§ß∑’Ë„π ¡°“√µà“ßÊ ¥â«¬«‘∏’∑“ߧ≥‘µ»“ µ√å æ∫«à“ ·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å¢Õß Henderson (1952) „Àâº≈°“√§”π«≥„°≈⇧’¬ß°—∫º≈°“√∑¥≈ÕߢÕ߇»…¬“ß°âÕπ ·≈–¬“߇ âπ¡“°∑’Ë ÿ¥ · ¥ß¥—ß Figure 1 ·≈– 2 ·≈–‰¥â ¡°“√· ¥ß§«“¡ —¡æ—π∏å√–À«à“ߧ«“¡™◊Èπ ¡¥ÿ≈ §«“¡™◊Èπ —¡æ—∑∏å·≈–Õÿ≥À¿Ÿ¡‘¥—ßπ’È

‡»…¬“ß°âÕπ

1− RH = exp(−0.002936 74 Tabs Meq0.775623 )

R2 = 0.8663 MRS = 0.0280

¬“߇ âπ

1− RH = exp(−0.069350 Tabs Meq0.736921 )

R2 = 0.8907 MRS = 0.0033

”À√—∫¬“ß·ºàπ ¡°“√·∫∫®”≈Õߧ«“¡™◊Èπ ¡¥ÿ≈∑“ߧ≥‘µ»“ µ√å¢Õß Halsey (1948) „Àâº≈°“√§”π«≥„°≈⇧’¬ß°—∫º≈°“√∑¥≈ÕߢÕß¡“°∑’Ë ÿ¥ · ¥ß¥—ß Figure 3 ·≈–‰¥â ¡°“√· ¥ß§«“¡ —¡æ—π∏å¢Õߧ«“¡™◊Èπ —¡æ—∑∏å¢ÕßÕ“°“»Õÿ≥À¿Ÿ¡‘·≈–§«“¡™◊Èπ ¡¥ÿ≈ ¥—ßπ’È

¬“ß·ºàπ

RH = exp(−11.08492

RTabs

)Meq−0.886330 )

R2 = 0.8827 MRS = 0.1027

‡¡◊ËÕ Tabs

§◊Õ Õÿ≥À¿Ÿ¡‘Õ“°“»Õ∫·Àâß, Kt §◊Õ √–¬–‡«≈“, ™—Ë«‚¡ßk, n §◊Õ §à“§ßµ—«MRS §◊Õ Mean residue square value

MRS =(MRpredicted,i − MRobserved,i )

2

i=1

N

∑N

2. §«“¡Àπ“·πàπª√“°Ø¢Õ߬“ß∏√√¡™“µ‘

®“°º≈°“√∑¥≈Õߧ«“¡Àπ“·πàπª√“°Ø ·≈–

Figure 1. Comparison of equilibrium moisture

content at relative humidity 10-95%

between experimental data and model

of crumb rubber at temperature 30oC

Figure 2. Comparison of equilibrium moisture

content at relative humidity 10-95%

between experimental data and model

of rubber stick at temperature 45oC

Page 8: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 342

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

«‘‡§√“–Àå ¡°“√∂¥∂Õ¬‚¥¬«‘∏’°”≈—ß ÕßπâÕ¬∑’Ë ÿ¥ “¡“√∂À“§«“¡ —¡æ—π∏å√–À«à“ߧ«“¡Àπ“·πàπª√“°Ø°—∫§«“¡™◊Èπ¢Õ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ‰¥â¥—ßπ’È

§«“¡™◊ÈπÕ¬Ÿà„π™à«ß 20-65% ¡“µ√∞“π·Àâßρ

‡»…¬“ß°âÕπ = 250.79+2.0892 M R2 = 0.9839 MRS = 0.0012

ρ¬“ß·ºàπ

= 274.20+2.6535 M R2 = 0.9262 MRS = 0.007

ρ¬“߇ âπ

= 256.48+2.5710 M R2 = 0.9637 MRS = 0.017

‡¡◊ËÕ ρ §◊Õ §«“¡Àπ“·πàπª√“°Ø¢Õß, °°./≈∫.‡¡µ√

M §◊Õ §«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘,% ¡“µ√∞“π·Àâß

æ∫«à“ §«“¡Àπ“·πàπª√“°Ø°—∫§«“¡™◊Èπ¢Õ߬“ß∏√√¡™“µ‘®–¡’§à“‡æ‘Ë¡¢÷Èπ„π≈—°…≥–‡™‘߇ âπ ÷Ëß¡’√Ÿª·∫∫ ¡°“√‡™àπ‡¥’¬«°—∫√Ÿª·∫∫ ¡°“√¢Õßß“π«‘®—¬∑’Ë¡’°“√»÷°…“¡“·≈â« (Wetchacama et al., 2000; ÿ¿«√√≥ ·≈–§≥–,2537; Õ√ÿ≥’ ·≈–§≥–, 2533)

3. ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“»¢Õ߬“ß∏√√¡™“µ‘

µ“¡∑’ˉ¥â«‘‡§√“–Àå„πÀ—«¢âÕ 2 ‡ªìπ°“√æ‘®“√≥“ª√‘¡“µ√√«¡∑—ÈߢÕ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ ·≈–ª√‘¡“µ√¢ÕßÕ“°“»∑’Ë·∑√°µ—«Õ¬Ÿà ¥—ßπ—Èπ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“»°Á®–·ª√º—π°—∫§«“¡™◊Èπ¢Õ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ â𠇙àπ°—π ®“°°“√«‘‡§√“–Àå ¡°“√∂¥∂Õ¬‡æ◊ËÕÀ“§«“¡ —¡æ—π∏å√–À«à“߇ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“»°—∫§«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘ ‰¥âº≈¥—ßπ’ȧ◊Õ

§«“¡™◊ÈπÕ¬Ÿà„π™à«ß 20-65% ¡“µ√∞“π·Àâßε

‡»…¬“ß°âÕπ = 100.40-0.3168 M R2 = 0.9819 MRS = 0.005

ε¬“ß·ºàπ

= 103.55-0.7097 M R2 = 0.9518 MRS = 0.007

ε¬“ß‡ âπ

= 93.953-0.3555 M R2 = 0.9197 MRS = 0.004

‡¡◊ËÕ ε §◊Õ §«“¡Àπ“·πàπª√“°Ø¢Õ߬“ß, °°./≈∫.‡¡µ√M §◊Õ §«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘,

% ¡“µ√∞“π·Àâß

®“°°“√»÷°…“ æ∫«à“ ‡¡◊ËÕ§«“¡™◊Èπ¢Õ߇»…¬“ß°âÕπ¬“ß·ºàπ ·≈–¬“߇ âπ ‡æ‘Ë¡¢÷È𠇪Õ√凴Áπµå™àÕß«à“ߢÕßÕ“°“»®–¡’§à“≈¥≈ß„π≈—°…≥–‡™‘߇ âπ · ¥ß¥—ß Figure 5 µ“¡≈”¥—∫ ´÷Ëß¡’√Ÿª·∫∫ ¡°“√‡™àπ‡¥’¬«°—∫√Ÿª·∫∫ ¡°“√¢Õßß“π«‘®—¬∑’Ë¡’°“√»÷°…“¡“·≈â« ( ÿ¿«√√≥ ·≈–§≥–, 2537;Õ√ÿ≥’ ·≈–§≥–, 2533)

4. §à“§«“¡√âÕπ®”‡æ“–¢Õ߬“ß∏√√¡™“µ‘

®“°°“√»÷°…“æ∫«à“ ‡¡◊ËÕ§«“¡™◊Èπ¢Õ߇»…¬“ß°âÕπ ¬“ß·ºàπ ¬“ß‡ âπ ·≈–¬“ß∂⫬ ‡æ‘Ë¡¢÷È𠧫“¡√âÕπ®”‡æ“–®–¡’§à“‡æ‘Ë¡¢÷Èπ„π≈—°…≥–‡™‘߇ âπ · ¥ß¥—ß Figure 6 ®“°°“√

Figure 3. Comparison of equilibrium moisture

content between experimental data and

expected data of rubber sheet at rela-

tive humidity of 10-95% and temper-

ature of 37.5oC

Figure 4. Comparison of apparent density of

natural rubber at various moisture

contents.

Page 9: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

«. ߢ≈“π§√‘π∑√å «∑∑.

ªï∑’Ë 29 (©∫—∫摇»… 2) æ.§. 2550 : ∫—≥±‘µ»÷°…“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ·≈–§≥–343

«‘‡§√“–Àå ¡°“√∂¥∂Õ¬‡æ◊ËÕÀ“§«“¡ —¡æ—π∏å√–À«à“ߧ«“¡√âÕπ®”‡æ“–°—∫§«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘ ‰¥âº≈¥—ßπ’ȧ◊Õ

§«“¡™◊ÈπÕ¬Ÿà„π™à«ß 20-65% ¡“µ√∞“π·Àâßcp‡»…¬“ß°âÕπ

= 3.3808+0.0993M R2 = 0.9633 MRS = 0.009

cp¬“ß·ºàπ

= 0.3905+0.0570M R2 = 0.9585 MRS = 0.015

cp¬“߇ âπ

= 1.9500+0.0171M R2 = 0.8153 MRS = 0.004

‡¡◊ËÕ cp

§◊Õ §«“¡√âÕπ®”‡æ“–¢Õ߬“ß, kJ/kgoC

M §◊Õ §«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘,% ¡“µ√∞“π·Àâß

´÷Ëß ¡°“√§à“§«“¡√âÕπ®”‡æ“–π’È ®–™à«¬„Àâ∑√“∫∂÷ߧ«“¡ “¡“√∂„π°“√®ÿ§«“¡√âÕπ¢Õ߬“ß∏√√¡™“µ‘∑’褈Ҥ«“¡™◊Èπµà“ßÊ ·≈–¡’ª√–‚¬™πåµàÕ°“√«‘‡§√“–Àå∂÷ß°√–∫«π°“√∂à“¬‚Õ𧫓¡√âÕπ„À⬓ß∏√√¡™“µ‘ ´÷Ëß¡’√Ÿª·∫∫ ¡°“√‡™àπ‡¥’¬«°—∫√Ÿª·∫∫ ¡°“√¢Õßß“π«‘®—¬∑’Ë¡’°“√»÷°…“¡“·≈â«(Wetchacama et al., 2000; ÿ¿«√√≥ ·≈–§≥–, 2537;Õ√ÿ≥’ ·≈–§≥–, 2533)

5. ¡°“√Õ∫·Àâß

®“°°“√∑¥≈ÕßÕ∫·Àâß™—Èπ∫“ߢÕ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ „π™à«ß§«“¡™◊Èπ‡√‘Ë¡µâπ 30-65% ¡“µ√∞“π·Àâß ”À√—∫‡»…¬“ß°âÕπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 100-130C§«“¡‡√Á«≈¡ 1.5-2.5 ‡¡µ√/«‘π“∑’ ·≈– ”À√—∫¬“ß·ºàπ ¬“ß‡ âπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 40-70C §«“¡‡√Á«≈¡ 1.5-2 ‡¡µ√/«‘π“∑’ æ∫«à“ §«“¡™◊Èπ≈¥≈߇¡◊ËÕ‡«≈“°“√Õ∫·Àâ߇æ‘Ë¡¢÷Èπ‡¡◊ËÕπ”¡“§”π«≥À“Õ—µ√“ à«π§«“¡™◊Èπ “¡“√∂· ¥ß§«“¡ —¡æ—π∏å√–À«à“ßÕ—µ√“ à«π§«“¡™◊Èπ°—∫‡«≈“ ‡¡◊ËÕ«‘‡§√“–À姫“¡ —¡æ—π∏å√–À«à“ßÕ—µ√“ à«π§«“¡™◊Èπ°—∫‡«≈“ æ∫«à“√Ÿª·∫∫ ¡°“√‡Õ¡æ‘√‘§—≈ “¡“√∂Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’∑’Ë ÿ¥

”À√—∫‡»…¬“ß°âÕπ ¡°“√¥—¥·ª≈ߢÕß Hendersonand Pabis (1961) · ¥ß¥—ß Figure 7 “¡“√∂Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’ ¥—ß ¡°“√

MR = a exp(−kt)

‡¡◊ËÕ k = 0.0021T2 - 0.4504T + 25.489R2 = 0.9606

a = -0.0001T2 + 0.0204T + 0.0197R2 = 0.9583

MRS = 1.22

”À√—∫¬“ß·ºàπ ·≈–¬“߇ âπ ¡°“√¢Õß Page(1949) “¡“√∂Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’· ¥ß¥—ß Figure 8·≈– 9 ·≈–¥—ß ¡°“√

MR = exp(−ktn )

Figure 5. Comparison of percentage of void

fraction in the bed of natural rubber at

various moisture contents.

Figure 6. Comparison of specific heat of natural

rubber at various moisture contents

Page 10: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 344

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

”À√—∫¬“ß·ºàπk = -0.00563T + 2.17806 R2 = 0.9997n = 0.00384T - 1.00227 R2 = 0.9971MRS = 0.877

”À√—∫¬“߇ âπk = -4.499x10-5T2 + 0.0345T-6.3161

R2 = 0.9967n = -8.848x10-5T2 + 0.0606T-9.9479

R2 = 0.9986MRS = 0.737

Figure 7. Relationship between moisture ratio and drying time of crumb rubber at initial

moisture content of 30-65% dry-basis for drying temperatures of 100-130oC.

‡¡◊ËÕ T §◊Õ Õÿ≥À¿Ÿ¡‘Õ“°“»Õ∫·Àâß, Ct §◊Õ √–¬–‡«≈“, ™—Ë«‚¡ßk,n §◊Õ §à“§ßµ—«

6. §à“ —¡ª√– ‘∑∏‘Ï°“√·æ√৫“¡™◊Èπ

®“°°“√∑¥≈ÕßÕ∫·Àâß™—Èπ∫“ߢÕ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ „π™à«ß§«“¡™◊Èπ‡√‘Ë¡µâπ 30-65% ¡“µ√∞“π·Àâß ”À√—∫‡»…¬“ß°âÕπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 100-130C§«“¡‡√Á«≈¡ 1.5-2.5 ‡¡µ√/«‘π“∑’ ·≈– ”À√—∫¬“ß·ºàπ ¬“ß‡ âπ „™âÕÿ≥À¿Ÿ¡‘Õ∫·Àâß 40-70C §«“¡‡√Á«≈¡ 1.5-2 ‡¡µ√/«‘π“∑’ ‚¥¬°“√„™â√Ÿª·∫∫ ¡°“√Õ“√å‡√‡π’¬ ‰¥âº≈¥—ßπ’È

Figure 8. Relationship between moisture ratio

and drying time of rubber sheet at initial

moisture content of 30-65% dry-basis

for drying temperatures of 50 and 70oC.

Figure 9. Relationship between moisture ratio

and drying time of rubber stick at initial

moisture content of 30-65% dry-basis

for drying temperatures of 50-70oC.

Page 11: 13supawan parameters 335-346100-130oC (crumb rubber) could be explained by the empirical model, which was the function of drying temperature and drying time. Key words : effective

«. ߢ≈“π§√‘π∑√å «∑∑.

ªï∑’Ë 29 (©∫—∫摇»… 2) æ.§. 2550 : ∫—≥±‘µ»÷°…“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ ”À√—∫°“√«‘‡§√“–Àå°“√Õ∫·Àâ߬“ß∏√√¡™“µ‘

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ·≈–§≥–345

‡»…¬“ß°âÕπ

D = 41.3857exp−6158.473T + 273.15

R2 = 0.971 MRS = 0.037

¬“ß·ºàπ

D = 4 ×10−5 exp−1192.368T + 273.15

R2 = 0.923 MRS = 0.044

¬“߇ âπ

D = 52.96805exp−6078.694T + 273.15

R2 = 0.913 MRS = 0.015

‚¥¬§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√ଗߺ≈ (D) ¢Õ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ â𠇪ìπøíß°å™—π°—∫Õÿ≥À¿Ÿ¡‘ ·≈–¡’§à“‡æ‘Ë¡¢÷Èπ‡ªìπ·∫∫‡Õ°´å‚ª‡ππ‡™’¬≈

√ÿªº≈°“√∑¥≈Õß

1. §«“¡™◊Èπ ¡¥ÿ≈¢Õ߇»…¬“ß°âÕπ ¬“ß·ºàπ ·≈–¬“߇ âπ ®–¡’§à“‡æ‘Ë¡¢÷Èπ ‡¡◊ËÕ§«“¡™◊Èπ —¡æ—∑∏å‡æ‘Ë¡¢÷Èπ„π™à«ßÕÿ≥À¿Ÿ¡‘ 35-60C ‡¡◊ËÕπ”¡“«‘‡§√“–ÀåÀ“√Ÿª·∫∫ ¡°“√∑’ˇÀ¡“– ¡ æ∫«à“ ¡°“√¢Õß Henderson (1952) Õ∏‘∫“¬º≈°“√∑¥≈ÕߢÕ߇»…¬“ß°âÕπ·≈–¬“߇ âπ ‰¥â¥’∑’Ë ÿ¥ à«π¬“ß·ºàπ ¡°“√¢Õß Halsey (1948) “¡“√∂Õ∏‘∫“¬º≈°“√∑¥≈Õ߉¥â¥’∑’Ë ÿ¥

2. §«“¡Àπ“·πàπª√“°Ø¢Õ߬“ßµ—«Õ¬à“ß∑—Èß 3 ™π‘¥¡’§à“‡æ‘Ë¡¢÷Èπµ“¡§«“¡™◊Èπ‡√‘Ë¡µâπ „π™à«ß§«“¡™◊Èπ 20-65%¡“µ√∞“π·Àâß ¡°“√§«“¡ —¡æ—π∏å°—∫§«“¡™◊Èπ‡ªìπ≈—°…≥–‡™‘߇ âπ

3. ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“»¢Õ߬“ßµ—«Õ¬à“ß∑—Èß3 ™π‘¥ ¡’§à“≈¥≈ßµ“¡ª√‘¡“≥§«“¡™◊Èπ‡√‘Ë¡µâπ „π™à«ß§«“¡™◊Èπ 20-65% ¡“µ√∞“π·Àâß ¡°“√§«“¡ —¡æ—π∏å°—∫§«“¡™◊Èπ‡ªìπ≈—°…≥–‡™‘߇ âπ

4. §«“¡√âÕπ®”‡æ“–¢Õ߬“ßµ—«Õ¬à“ß∑—Èß 3 ™π‘¥ ¡’

§à“‡æ‘Ë¡¢÷Èπµ“¡§«“¡™◊Èπ‡√‘Ë¡µâπ „π™à«ß§«“¡™◊Èπ 20-65%¡“µ√∞“π·Àâß ¡°“√§«“¡ —¡æ—π∏å°—∫§«“¡™◊Èπ‡ªìπ≈—°…≥–‡™‘߇ âπ

5. Õ—µ√“ à«π§«“¡™◊Èπ ”À√—∫‡»…¬“ß°âÕπ ®–¡’§à“≈¥≈߇¡◊ËÕ‡«≈“·≈–Õÿ≥À¿Ÿ¡‘¢Õß°“√Õ∫·Àâ߇æ‘Ë¡¢÷Èπ √Ÿª·∫∫ ¡°“√Õ∫·Àâß™—Èπ∫“ß∑’Ëπ”¡“„™â„π°“√Õ∏‘∫“¬º≈°“√∑¥≈Õß· ¥ß„π√Ÿª·∫∫¢Õß ¡°“√‡Õ¡æ‘√‘§—≈ ·≈– ¡°“√°÷Ëß∑ƒ…Æ’

6. §à“ —¡ª√– ‘∑∏‘Ï°“√·æ√৫“¡™◊Èπ ”À√—∫‡»…¬“ß°âÕπ ¬“ß·ºàπ ¬“ß‡ âπ · ¥ß„π√Ÿª·∫∫ ¡°“√Õ“√å‡√‡π’¬ ·≈–‡ªìπ§à“ —¡ª√– ‘∑∏‘Ï°“√·æ√ଗߺ≈®–‡ªìπøíß°å™—π°—∫Õÿ≥À¿Ÿ¡‘ ·≈–¡’§à“‡æ‘Ë¡¢÷Èπ‡ªìπ·∫∫‡Õ°´å‚ª‡ππ‡™’¬≈

ß“π«‘®—¬π’ȇªìπ°“√»÷°…“À“æ“√“¡‘‡µÕ√å∑’Ë®”‡ªìπ„π°“√«‘‡§√“–Àå°“√Õ∫·ÀâߢÕ߬“ß∏√√¡™“µ‘ ¿“¬„µâ‡ß◊ËÕπ‰¢°“√Õ∫·Àâß∑’ËÕÿ≥À¿Ÿ¡‘µà“ßÊ º≈°“√∑¥≈Õß·≈– ¡°“√·∫∫®”≈Õß∑“ߧ≥‘µ»“ µ√å “¡“√∂𔉪„™âª√–‚¬™πå„π°“√∑”𓬰“√Õ∫·ÀâߢÕ߬“ߥ‘∫∏√√¡™“µ‘ ‰¥â·°à ‡»…¬“ß°âÕπ ¬“ß·ºàπ¥‘∫ ¬“ß·ºàπ√¡§«—𠇪ìπµâπ º≈°“√∑¥≈Õ߉¥â∑”°“√∑¥≈Õߧ√Õ∫§≈ÿ¡™à«ß§«“¡™◊Èπ‡√‘Ë¡µâπ¢Õ߬“ß∏√√¡™“µ‘„π™à«ß∑’Ë¡’°“√„™âß“π®√‘ß (§«“¡™◊Èπ‡√‘Ë¡µâπ 20-65% ¡“µ√∞“π·Àâß) ·≈–Õÿ≥À¿Ÿ¡‘∑’Ë„™â„π°“√Õ∫·Àâߧ√Õ∫§≈ÿ¡∑—È߬“ß·ºà𵓰·Àâß (Õÿ≥À¿Ÿ¡‘µË”°«à“ 70oC) ¬“ß·ºàπ√¡§«—π (Õÿ≥À¿Ÿ¡‘40-60oC) ·≈–°“√Õ∫·Àâ߬“ß·∑àß¡“µ√∞“π‡Õ ∑’Õ“√å(Õÿ≥À¿Ÿ¡‘ Ÿß°«à“ 100oC) ´÷Ëß®—¥‡ªìπ ‘π§â“ÕÕ°∑’Ë ”§—≠¢Õߪ√–‡∑»‰∑¬Õ¬à“ßÀπ÷Ëߥ⫬ æ∫«à“ æ“√“¡‘‡µÕ√åµà“ßÊ ‰¥â·°à§à“§«“¡™◊Èπ ¡¥ÿ≈ §à“§«“¡Àπ“·πàπª√“°Ø ‡ªÕ√凴Áπµå™àÕß«à“ߢÕßÕ“°“» §à“§«“¡√âÕπ®”‡æ“– ¡°“√Õ∫·Àâß™—Èπ∫“ß ”À√—∫¬“ß·µà≈–™π‘¥ “¡“√∂𔉪„™â‡ªìπ¢âÕ¡Ÿ≈æ◊Èπ∞“π„π°“√æ—≤π“·≈–®”≈Õß√–∫∫Õ∫·ÀâߢÕ߬“ß·µà≈–™π‘¥ ‡æ◊ËÕ„À≥â·π«∑“ß°“√Õ∫·Àâß∑’ˇÀ¡“– ¡¿“¬„µâ ¿“«–¢ÕßÕ“°“»·«¥≈âÕ¡Àπ÷ËßÊ ‚¥¬∑“ߧ≥–ºŸâ«‘®—¬‡Õ߉¥â¡’‚§√ß°“√«‘®—¬∑’˵àÕ‡π◊ËÕß®“°ß“π™ÿ¥π’ȧ◊Õ °“√»÷°…“§«“¡‡ªìπ‰ª‰¥â¢Õß°“√Õ∫·Àâ߬“ß·ºàπ¥â«¬≈¡√âÕπ√à«¡°—∫Õ‘πø√“‡√¥ (ß∫ª√–¡“≥·ºàπ¥‘π ªï æ.». 2549) ·≈–‚§√ß°“√«‘®—¬ °“√Õ∫·Àâß∑’ˇÀ¡“– ¡¢ÕßÕÿµ “À°√√¡º≈‘µ¬“ß·∑àß‡Õ ∑’Õ“√å ( ”π—°ß“π°Õß∑ÿπ«‘®—¬·Ààß™“µ‘ ( °«.) ªï æ.». 2548-2549) ´÷Ëß∑—Èß Õß‚§√ß°“√«‘®—¬π’È®”‡ªìπµâÕßÕ“»—¬æ“√“¡‘‡µÕ√å‡À≈à“π’È„π°“√À“·π«∑“ß°“√Õ∫·Àâß∑’ˇÀ¡“– ¡µàÕ‰ª

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Songklanakarin J. Sci. Technol.

Vol. 29 (Suppl.2) May 2007: Grad. Res. 346

Parameters for the analysis of natural rubber drying

Tirawanichakul, S., et al.

°‘µµ‘°√√¡ª√–°“»

„π°“√«‘®—¬§√—Èßπ’ȉ¥â√—∫∑ÿπÕÿ¥Àπÿπ°“√«‘®—¬·≈–«‘∑¬“-π‘æπ∏å√–¥—∫∫—≥±‘µ»÷°…“ ¡À“«‘∑¬“≈—¬ ߢ≈“π§√‘π∑√åª√–®”ªïß∫ª√–¡“≥ 2548 ·≈–∑ÿπ®“° ”π—°ß“π π—∫ πÿπ°Õß∑ÿπ«‘®—¬ ª√–®”ªï 2548 µ≈Õ¥®π‡§√◊ËÕß¡◊Õ·≈–Õÿª°√≥å„π°“√∑¥≈Õßµà“ßÊ ¢Õß¿“§«‘™“«‘»«°√√¡‡§¡’ ¿“§«‘™“«‘»«°√√¡‡§√◊ËÕß°≈ ·≈–¿“§«‘™“øî ‘° å ¡À“«‘∑¬“≈—¬ ߢ≈“-π§√‘π∑√å «‘∑¬“‡¢µÀ“¥„À≠à ·≈–∫ÿ§≈“°√∑à“πµà“ßÊ ∑’ˇ°’ˬ«¢âÕß ‰¥â·°à ºŸâ™à«¬»“ µ√“®“√¬å‰æ‚√®πå §’√’√—µπå ”π—°ª√– “πß“π™ÿ¥‚§√ß°“√«‘®—¬ "°“√æ—≤π“Õÿµ “À°√√¡¬“ßæ“√“" §ÿ≥ ¡æ√ æ߻墮√ ∑à“πºŸâ®—¥°“√∫√‘…—∑Õ—≈≈“¬¥å‡∑§‡ÕÁ𮑇π’¬√‘ß ®”°—¥ ‡¢µ∫÷ß°ÿà¡ °√ÿ߇∑æ¡À“π§√ ·≈–§ÿ≥∑πß»—°¥å ‡ π“ߧπ‘°√ ∑à“πºŸâ®—¥°“√‚√ßß“π¬“ß·∑àß∫√‘…—∑‡´“∑å·≈π¥å√’´Õ√å´ ®”°—¥ “¢“∂È”æ√√≥√“¬ ®—ßÀ«—¥π§√»√’-∏√√¡√“™ ®π∑”„Àâ°“√¥”‡π‘πß“π«‘®—¬§√—Èßπ’È ”‡√Á®≈ÿ≈à«ß‰ª‰¥â¥â«¬¥’ §≥–ºŸâ«‘®—¬¢Õ¢Õ∫§ÿ≥¡“ ≥ ∑’Ëπ’È

‡Õ° “√Õâ“ßÕ‘ß

°√¡«‘™“°“√‡°…µ√. 2547. ∂“π°“√≥å°“√º≈‘µ·≈–°“√µ≈“¥¬“ß. ‡Õ° “√«‘™“°“√¬“ßæ“√“ ª√–®”ªï 2547 ‡≈à¡∑’Ë20. °√¡«‘™“°“√‡°…µ√ °√–∑√«ß‡°…µ√·≈– À°√≥å.

∏π‘µ «— ¥‘χ «’ ¡™“µ‘ ‚ ¿≥√≥ƒ∑∏‘Ï Õ¥‘»—°¥‘Ï π“∂°√≥°ÿ≈·≈–‡ªïò¬¡»‘≈ªá ∑Õß∑‘æ¬å. 2542. °“√Õ∫·Àâ߇¡≈Á¥„π¡–¡à«ßÀ‘¡æ“πµå¥â«¬‡§√◊ËÕßÕ∫·Àâß·∫∫À¡ÿπ. «.‡°…µ√-»“ µ√å («‘∑¬.). 33: 159-169.

¡™“µ‘ ‚ ¿≥√≥ƒ∑∏‘Ï. 2540. °“√Õ∫·Àâ߇¡≈Á¥æ◊™·≈–Õ“À“√∫“ߪ√–‡¿∑. §≥–æ≈—ßß“π·≈–«— ¥ÿ ¡À“«‘∑¬“≈—¬‡∑§‚π‚≈¬’æ√–®Õ¡‡°≈â“∏π∫ÿ√’.

ÿ¿«√√≥ Ø‘√–«≥‘™¬å°ÿ≈ ·≈–¬ÿ∑∏π“ Ø‘√–«≥‘™¬å°ÿ≈. 2537.Õÿª°√≥åÕ∫·Àâ߇¡≈Á¥æ◊™™—Èπ∫“ß: æ“√“¡‘‡µÕ√å¢Õß°“√Õ∫·Àâß™—Èπ∫“߇π◊ÈÕ„π‡¡≈Á¥¡–¡à«ßÀ‘¡æ“πµå. «. ߢ≈“-π§√‘π∑√å. «∑∑. 16(4): 381-392.

Õ√ÿ≥’ ºÿ¥ºàÕß ¡™“µ‘ ‚ ¿≥√≥ƒ∑∏‘Ï ·≈–«“√ÿ≥’ ‡µ’¬. 2533.°“√»÷°…“§à“æ“√“¡‘‡µÕ√å ”À√—∫«‘‡§√“–Àå°“√Õ∫·Àâ߇¡≈Á¥¢â“«‚æ¥. «‘»«°√√¡ “√. 4: 95-101.

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