Drying characteristics of Buna-S rubber; Vacuum shelf drying, rotary vacuum drying, cabinet air drying, and through-circulation air drying

摘要

The results of these studies of the drying of buna-S crumb rubber may be summarized as follows;1. The most effective drying procedure of those investigated was through circulation air drying. This procedure produced by crumb in 1 to 11/2 hours whereas other procedures required extended drying periods;2. Constant rates of drying were correlated by empirical equations: Vacuum Shelf drying, Rc=0.00589t/P1 2-0.1238 31 Rotary vacuum drying, R1c=0.00358 tst/P12 -0.039433 Cabinet air drying, h=0.008V+4.75 35 Through circulation air drying, h=1.084V0.8 36;3. The falling rate data were correlated using reduced rate relations involving power functions. The general expression employed was Rr=Wkr 28 The falling rate drying by each procedure was characterized by an average value of k: Vacuum shelf drying, k = 1.30; Rotary vacuum drying, k = 1.03; Cabinet air drying, k = 1.68; Through circulation air drying, k = 1.93;4. Values of k were used with curves relating W r and dWr Rr to calculate the falling rate time of drying and moisture content-time data.