Abstract: A method for controlling the gas recycle loop of an ozone bleaching process wherein an ozone generator produces an ozone containing gas from an oxygen containing feed gas and delivers the ozone containing gas to an ozone reactor at a variable flow rate responsive to reactor ozone demand. Pulp is bleached with the ozone containing gas, thereby producing an exhaust gas having a flow rate that varies in response to the flow rate of the ozone containing gas delivered to the ozone reactor. The exhaust gas is then recovered and its flow rate is modified within the recycle loop so that an amount equivalent to reactor ozone demand is returned to the ozone generators. The oxygen content of the oxygen containing feed gas is monitored at or near the inlet of the ozone generator and an amount of fresh oxygen is supplied to the oxygen containing feed gas to obtain a predetermined level of oxygen therein.

Abstract: A folded sheet article (20) comprises a sheet (22) of material having mutually transverse sets of concertina folds (24, 26) and two diagonally opposite stiff portions (28, 30) at respective corner segments (32, 34) of the sheet (as disclosed in the inventor's prior U.S. Pat. No. 5,156,898) and has a pocket (40) at at least one of the segments (32, 34). Pocket (40) may be formed separately, may comprise the stiff portion (28), which may be folded back onto itself to form the pocket (40), or may (alone or together with said portion (28)) be formed from the sheet (22). The stiffening may be provided by a removable card (58) in pocket 40). Such card (58) may bear coded information (60) related to information (62) borne by sheet (22). Pocket (40) may have an egress retarder (64) to retard egress of a card (58).

Abstract: A sheet of material having a first set of concertina folds and, so as to be transverse to these when the sheet is folded with these folds, a second set of concertina folds, the sheet being provided with two diagonally opposite holding portions at segments thereof, which segments are at or near diagonally opposite corners of the sheet and defined by folds and/or edges thereof, one of the holding portions being stiff and the opposite holding portion having a part extending beyond the remainder of the sheet when folded, so as to be suitable to be held in a binder; the part may be pre-bound in a book or may have punch-holes, suitable for a ring-binder; the material, part from the stiff portion, may be of paper-like plastics material that is tear-resistant.

Abstract: Sheet means (10) comprises a sheet of material (12) having mutually transverse sets of concertina folds (14, 16), sealing means (18, 20) to seal the same in a folded condition and defined opening means (18, 20), e.g. a marked and/or weakened break line (54) at which the sealing means can be opened, attachment means (36) for attaching the sheet means (10) to an article (28), diagonally opposite segments (22) of said sheet (12) being adapted one for attachment to the article and the other to be pulled free to open the sheet fully with a single movement once the sealing means have been opened. The penultimate section (80) and ultimate section (86) may project respectively beyond opposite sides (82, 88) of the underlying sections to allow adhesive strips (18, 20) to affix directly to the article (28) or only the ultimate thickness (segment) (26) may be extended (at 90) and so project.

Abstract: A sheet of paper or like material having a first and a second set of concertina folds with the second set of folds being transverse to the first set when the sheet is folded. The sheet is provided with two stiff portions at diagonally opposite corner segments of the sheet, so that the sheet can be unfolded with a single movement and possibly using only one hand to grasp and unfold the sheet.