Abstract:
Methods are provided for crystallizing a filler, especially in order to precipitate calcium carbonate on the surfaces of solids in the short circulation of a fiber web machine by feeding carbon dioxide and lime milk to the liquid flow of the short circulation and allowing them to react with one another, is characterized in that the feed system, the mixing method and/or mixing rate of the chemicals are selected such that a size distribution of the calcium carbonate crystals suitable for the purpose is obtained. Moreover, the invention relates to an approach system for a fiber web machine applying this method, characterized in that it is provided with devices for feeding and mixing carbon dioxide and lime milk into the liquid flow at such a rate that the applicable size distribution of the calcium carbonate crystals is obtained.
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:
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.
Abstract:
A method including: introducing a first chemical to a first passage of a mixing apparatus attached to the process liquid flow pipe; introducing an injection liquid into a second passage of the mixing apparatus; introducing to a third passage of the mixing apparatus a second chemical having an electrical charge opposite to the electric charge of the first chemical; injecting the first chemical into the injection liquid by passing the first chemical through a passage between the first passage and the second passage; introducing the mixture of the first chemical and the injection liquid to a process liquid flowing through the process liquid flow pipe, and introducing the second chemical from the third passage to the process liquid in the process liquid flow pipe, wherein the second chemical passes from the third passage to the process liquid a distance from the injection of the first chemical into the injection liquid.