| 摘要 |
PCT No. PCT/GB91/00896 Sec. 371 Date Jan. 13, 1994 Sec. 102(e) Date Jan. 13, 1994 PCT Filed Jan. 5, 1991 PCT Pub. No. WO91/19145 PCT Pub. Date Dec. 12, 1991Apparatus for drying a wet material such as sewage sludge comprises a drum (11) mounted for revolution about a horizontal axis and containing interconnected inner (22) and outer (21) concentric spirals containing a continuously-recirculatable charge of particulate heat exchange/pulverizing medium in each coil of the spirals. Sludge is introduced at one end and mixed with the heated charge; the charge and sludge traverse the length of the drum together through the outer spiral while drying takes place; the dried material is removed at the other end and the charge transferred to the inner spiral for transmission to the first end while re-heating takes place by ducted heated air. |
