Abstract: The invention relates to a method for modifying nanofibrillar cellulose composition, comprising—preparing fibrous dispersion of ionically charged nanofibrillar cellulose (NFC), and—applying heat treatment at a temperature of at least 90° C. to the fibrous dispersion until the viscosity of NFC starts to decrease. The viscosity of the heat-treated NFC is reversible by applying shear forces to the NFC.

Abstract: A method for concentrating fibril cellulose including subjecting aqueous fibril cellulose at a concentration of not higher than 5% to pressure filtration where water is removed from the fibril cellulose by applying pressure to the aqueous fibril cellulose, and continuing the pressure filtration continued to an end point where over 50% of the water initially present is removed from the fibril cellulose. The pressure filtration is performed at a temperature of 30° C. or higher.

Abstract: The invention relates to a method for processing chemically modified fibril cellulose. The method includes introducing chemically modified fibril cellulose material to a thermal drying device including a belt in such a way that the fibril cellulose material forms at least one bar onto the belt, and dewatering the chemically modified fibril cellulose material on the belt using heated air flow having a temperature of at least 40 ° C. in order to concentrate and/or dry the chemically modified fibril cellulose material in such a way that the dry solids content of the fibril cellulose material after the thermal drying device is at least 10%. In addition, this invention relates to a thermal drying device, a system for processing chemically modified fibril cellulose, a method and a system for redispersing the fibril cellulose, and a fibril cellulose material.

Abstract: The invention relates to a method for modifying nanofibrillar cellulose composition, comprising—preparing fibrous dispersion of ionically charged nanofibrillar cellulose (NFC), and—applying heat treatment at a temperature of at least 90° C. to the fibrous dispersion until the viscosity of NFC starts to decrease. The viscosity of the heat-treated NFC is reversible by applying shear forces to the NFC.

Abstract: An agent for oilfield applications capable of being dispersed in water is nanofibrillar cellulose. The nanofibrillar cellulose mixed in water gives shear-thinning behavior to the composition, which is pumped to a subterranean oil-containing formation to aid in oil recovery.

Abstract: The invention relates to a method for processing chemically modified fibril cellulose. The method includes introducing chemically modified fibril cellulose material to a thermal drying device including a belt in such a way that the fibril cellulose material forms at least one bar onto the belt, and dewatering the chemically modified fibril cellulose material on the belt using heated air flow having a temperature of at least 40° C. in order to concentrate and/or dry the chemically modified fibril cellulose material in such a way that the dry solids content of the fibril cellulose material after the thermal drying device is at least 10%. In addition, this invention relates to a thermal drying device, a system for processing chemically modified fibril cellulose, a method and a system for redispersing the fibril cellulose, and a fibril cellulose material.

Abstract: A method for concentrating fibril cellulose including subjecting aqueous fibril cellulose at a concentration of not higher than 5% to pressure filtration where water is removed from the fibril cellulose by applying pressure to the aqueous fibril cellulose, and continuing the pressure filtration continued to an end point where over 50% of the water initially present is removed from the fibril cellulose. The pressure filtration is performed at a temperature of 30° C. or higher.

Abstract: An agent for oilfield applications capable of being dispersed in water is nanofibrillar cellulose. The nanofibrillar cellulose mixed in water gives shear-thinning behavior to the composition, which is pumped to a subterranean oil-containing formation to aid in oil recovery.