| Titre : |
Investigations into the controlled drying of sheepskins : I. Establishment of the drying characteristics of the system |
| Type de document : |
texte imprimé |
| Auteurs : |
J. R. Yates, Auteur |
| Année de publication : |
1966 |
| Article en page(s) : |
p. 171-188 |
| Note générale : |
Bibliogr. |
| Langues : |
Américain (ame) |
| Catégories : |
Cuirs et peaux -- Séchage
Cuirs et peaux de moutons
Peaux brutes -- Teneur en eau
Température
Température de retrait
|
| Index. décimale : |
675 Technologie du cuir et de la fourrure |
| Résumé : |
The drying of sheepskins is followed in a commercial drying estab-lishment in order to ascertain what is the acceptable level of water content in a "dry" skin. A water content (dry weight basis) in the range 14-24 percent is acceptable. The time required to reach this level is found to vary tremendously with the prevailing climatic conditions. On a laboratory scale, the influence of temperature on drying rate is investigated, and from the drying rate curves at the different tempera-tures, the "apparent activation energy" of drying is calculated over the range of water contents investigated. The value of this activation energy is of the order of 5-8 Kcals/mole, and does not vary with the water content of the skin down to about ten percent but thereafter shows a marked rise. It is also dependent on the skin thickness. Drying results in a decreased amount of water uptake and an increase in the amount of extractable nitrogen on subsequent soaking, and an increase in the shrinkage temperature of the skin. |
| Note de contenu : |
- MATERIALS
- METHODS : Effect of climatic conditions on the drying process - Effect of temperature on draying rate - Effect of degree of drying on extractable nitrogen - Effect of degree of drying on subsequent water uptake - Measurement of shrinkage temperature at different water contents
- RESULTS AND DISCUSSION : Effect of changing climatic conditions on rate of drying - Effect of temperature on rate of drying - Calculation of "apparent activation energy of drying - Effect of degree of drying on subsequent water uptake - Effect of degree of drying on shrinkage temperature
- Table 1 : Actual water loss in Mg./Min. for series 2 skin
- Table 2 : "Apparent activation energies" of drying at different regain levels
- Table 3 : "Apparent activation energies" for low water content
- Table 4 : Analysis of variance of skin thickness and water cotent on "apparent activation energy"
- Table 5 : Extractable nitrogen in Mg/Gm dry WT. of skin, with the water content (d.w.b.)
- Table 6 : Analysis of variance and the industrial regression coefficients for the 15 sets of extractable nitrogen-water content data
- Table 7 : Variation of final water content after soaking for 72 hours at 1°C. With the initial water content
- Table 8 : Analysis of co-variance for the initial and final water contents of the skin samples, and the Bo coefficients for the six positions |
| En ligne : |
https://drive.google.com/file/d/1F6jLD8P9e_xXLbLTNjE2NbLGjGdH-d8J/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37941 |
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXI (Année 1966) . - p. 171-188
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Investigations into the controlled drying of sheepskins in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXI (Année 1966)
