| 摘要 |
In a vertical digester for producing chemical pulp, or other vessel for treating a slurry of comminuted fibrous cellulosic material, the cost of manufacturing the shell is significantly reduced by eliminating the external step increases in the digester shell. The digester shell has a substantially constant internal diameter from just below the inlet to just above the outlet, screen assemblies being provided by an internal transition (e.g. conical) having an angle of convergence of less than 40 DEG (e.g. about 10-25 DEG ) above each screen assembly so that the slurry flows through the transition without bridging or hang-up, and a step increase, or other increase, in diameter back to the first diameter after the screen assembly. |
