Method and an apparatus for adding an additive to a cement-like composition

A method for adding an additive to a cement-like composition, the method comprising:

• forming a liquid flow,
• supplying additive to the system, wherein the additive comprises nanocellulose, by means of an injection fluid forming a side flow,
• dosing said additive to said liquid flow by supplying it to the liquid flow substantially transversely to the flowing direction of said liquid flow, in such a way that a mixture is formed which comprises said additive and liquid,
• discharging the injection fluid to the liquid flow, and
• adding the formed mixture as an additive to a cement-like composition in such a way that such that
• the rate at which the additive is fed to the liquid flow, is at least three times the flow rate of the liquid flow;
• wherein
• the side flow is smaller than 10 volume percent (vol %) of the total flow of the liquid to be processed.

An apparatus for adding an additive to a cement-like composition, comprising:

• a liquid flow channel,
• means for supplying additive to said liquid flow channel,
• a dosing point in said flow channel, comprising one or more feeding means opening into the flow channel and directed substantially transversely to the flow direction of the liquid flow intended for the liquid flow channel, and arranged to feed said additive in such a way that the additive is mixed to the flow at the dosing point to form a mixture comprising additive and liquid,
• mixing means for mixing the mixture to a cement-like composition, and
• an injection fluid feed channel for feeding injection fluid, wherein the injection fluid feed channel is a side flow which is separated from the liquid flow, and is recombined with the liquid flow at the dosing point.

A method for adding an additive to a cement-like composition, wherein the method comprises:

• forming a liquid flow,
• supplying additive to the system, wherein the additive comprises nanocellulose, by means of an injection fluid forming a side flow,
• dosing said additive to said liquid flow by feeding it to the liquid flow counter-currently to the flowing direction of said liquid flow, in such a way that a mixture is formed which comprises said additive and liquid,
• discharging the injection fluid to the liquid flow, and
• adding the formed mixture as an additive to a cement-like composition in such a way that such that
• the rate at which the additive is fed to the liquid flow, is at least three times the flow rate of the liquid flow;
• wherein
• the side flow is smaller than 10 volume percent (vol %) of the total flow of the liquid to be processed.