| 摘要 |
The disclosure related in part to a novel and highly superior high bulk pulp formed of lignin-containing fibers, and to process conditions for manufacture of the pulp. The process involves selection of a lignin-containing fiber source, having a lignin content of at least about 10%, and thermomechanically pulping the fiber source under temperature/pressure conditions of 300 DEG F.-350 DEG F./50 psig-120 psig and a refiner energy utilization of about 8-35 HPT/ADT, using a double disc, counter rotating disc refiner. The thermomechanically produced fibers are characterized by a high degree of stiffness, and an extremely smooth surface, free of fine fibril formation and thus substantially non-self-bonding. The new pulp has a wide variety of specialty uses which are attractive in terms of both economics and technical performance, because of the exceptionally high bulk and other distinctive characteristics of the fiber. Novel and highly superior filter media, formed using the new pulp which filter media are particularly useful in the filtration of lube oil, fuel and air. The filter media are formed by a random lay-up of the lignin-containing fibers, typically with selected other pulp fibers having technical characteristics suitable for filter media utilization. Suitable lignin-containing fiber, produced under conditions of the invention, may be substituted with minimum effort for conventional technical fibers utilized in furnishes intended for filter media production. The new filter media are characterized by exceptionally high bulk, void volume and dust capacity-high critical characteristics of filter media, and provide equal or superior product performance at significant reductions in production cost and/or exceptional improvement in filtration performance at equivalent production cost. |
