(under subclass 233) Apparatus having means to positively force the flow of digestion chemicals through the material being treated.
(1) Note. The material is usually forced through a separate conduit, which conduit may be entirely in the digester or may be outside of the digester proper.
(2) Note. This subclass does not provide for circulation of the treating chemical or stock material within the digester by heating means alone where the circulation is not through the separate conduit or orifice such as, for example circulation caused by the introduction of steam alone. For such subject matter search subclass 250 below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
243+, for apparatus in which the circulation is caused by mechanical stirring of the contents of the digester.
