Abstract:
A method to form a fibrous web including: introducing a furnish to a headbox of a fiber web machine, wherein the furnish includes a thick stock component and a filtrate, injecting a gas into to the furnish to form a foamed furnish, and laying the foamed furnish on a wire or between wires of a wire section of the fiber web machine to form the fibrous web from the foamed furnish.
Abstract:
A method of and an arrangement for adding at least one additional stock component to an approach flow system (30) of a fiber web machine by mixing the at least one additional stock component to a fibrous stock such that the stock flow is equalized (50) and the at least one additional stock component is introduced to the stock flow by injection mixing (80).
Abstract:
The present invention relates to a method of producing precipitated calcium carbonate (PCC) where a retention/strength enhancing chemical is added to milk of lime to form a mixture thereof prior to adding the mixture of the retention/strength enhancing chemical and milk of lime to paper making stock in a pipeline leading to a headbox of a paper making machine, whereafter carbon dioxide is introduced to the paper making stock, and the carbonation reaction between milk of lime and carbon dioxide is allowed to proceed in the presence of both fibres and the retention/strength enhancing chemical.
Abstract:
An arrangement for mixing a fluid to a process liquid by using at least one mixing station and a method of operating the arrangement to feed injection or mixing liquid to injection mixers arranged on a periphery of a flow pipe transferring a process liquid. The arrangement and the method are applicable for the injection of mixers and chemical mixing in processes for the wood processing industry.
Abstract:
A method and a reactor to crystalize calcium carbonate and to form crystals in a liquid flow (F) with the concentration of 2.5% to 5% inside or on the surfaces of a fiber dispersion containing solid matter. The method includes feeding carbon dioxide (CO2) and lime milk (LM) (Ca(OH)2) into the liquid flow and reacting the CO2 with the Ca(OH)2 wherein the carbon dioxide (CO2) and/or lime milk (LM) is injected with a mixer crosswise into the liquid flow (F) and the injection is performed with a feed tube (2) to cause a dwell time of the crystallizing reaction of 0.5 to 10 seconds before a nozzle (20) of the reactor (1), after which the liquid flow (F) is mixed with the liquid or fiber suspension in container (4)
Abstract:
A method of dosing a nanocellulose suspension in gel phase into a second suspension, wherein the method comprises the steps of: providing said nanocellulose suspension in gel phase; providing said second suspension; bringing said nanocellulose suspension in gel phase in contact with said second suspension; wherein the method comprises a step of subjecting said nanocellulose suspension in gel phase to a shear rate of more than 500 l/s, simultaneously with and/or immediately prior to the step of bringing said nanocellulose suspension in gel phase and said second suspension in contact with each other.
Abstract:
A method of manufacturing a fibrous web including: preparing furnish of a thick stock component and filtrate, preparing foamed furnish by mixing a surfactant and gas into the furnish, introducing the foamed furnish to a headbox of a fiber web machine, and laying the foamed furnish on a wire or between wires of a wire section of a fiber web machine for forming the fibrous web, wherein the preparation of the foamed furnish by injecting the gas uses an injection liquid to the furnish.