摘要:
There is a need to enhance the bleaching effect achieved when bleaching mechanical and chemithermomechanical pulp with a reductive bleaching agent. This can be achieved with the present invention, which relates to a method for manufacturing bleached mechanical and chemithermomechanical pulp including that lignocellulose material, preferably wood in chip form, is caused to pass through at least one preheater or through a chemical treatment system, a steam separator and a refiner where the lignocellulose material is converted into a pulp suspension which, after steam separation, is passed at least to a storage vessel (latency chest) and to a screening department, from which the major part of the pulp suspension is taken out as a substantially finished product or is taken out and passed to further treatment steps. The reductive bleaching agent is added to the advancing pulp suspension without the use of a bleaching tower or the like. The method is characterized by adding the bleaching agent at a location downstream of the refiner and upstream of the screening department, and by bleaching the pulp under the given drastic condition from the aspect of temperature and the given minimized oxygen access at said location and immediately downstream of said location.
摘要:
The present invention relates to a nitrogen containing fertilizer for plant growth and intended to be administered to growth substrate either alone or in mixture with other fertilizers. The invention is characterised in that the fertilizer is comprised of the L-form of a basic protein amino acid or its salt.
摘要:
The present invention relates to a nitrogen containing fertilizer for plant growth and intended to be administered to growth substrate either alone or in mixture with other fertilizers. The invention is characterised in that the fertilizer is comprised of the L-form of a basic protein amino acid or its salt.
摘要:
The present invention relates to security paper and security paperboard that comprises respectively base paper and base paperboard having one or several layers of pulp fibre, plus a surface treatment layer on at least one side of the base paper and base paperboard, wherein said layer is congruent with said base paper and base paperboard, and wherein at least one layer forms part of at least one local deviation in the form of a distinctive mark. The invention is characterised in that the local deviation includes locally compressed material plus a local surface treatment layer whose thickness exceeds the thickness of the corresponding surrounding and outwardly lying surface treatment layer. The present invention also relates to a method of manufacturing security paper and security paperboard.
摘要:
The present invention relates to a method for bleaching mechanical and chemithermomechanical pulp including that an advancing pulp suspension obtained after that the fibres are laid free is prebleached by adding reductive bleaching agent to the pulp suspension in a location just after the fibres are laid free and that the bleaching is carried out under given conditions in the form of high temperature and minimized oxygen access in respect of said adding location and immediately downstream of said location, characterized in, that the in the described manner prebleached pulp is subjected to at least one further bleaching treatment including that the pulp is bleached with an oxidizing bleaching agent, preferably peroxide bleaching agent, reinforced with borohydride.
摘要:
There is a need for a cheaper method of producing bleached TMP and CTMP without impairing the properties of the pulp. This is made possible by the present invention, which relates to a method of producing said pulps in which finely divided lignocellulosic material is defibrated after pretreatment and the resultant pulp is bleached in the form of a suspension with bleaching agent that increases the anionic charge of the pulp fibres, whereafter the pulp suspension is cleaned and then possibly further treated, for instance bleached, characterised in that the defibration is effected with the aid of a) a refiner that has counter-rotating refining discs while using an extra high temperature (HTDD), or b) a refiner that has a single rotating refining disc(s) having a single refining zone or two parallel refining zones, while using an extra high temperature and while rotating the disc(s) at an extra high speed (RTS), and in that the cleaning treatment comprises first screeming the pulp suspension and them hydrocyclone cleaning said suspension, wherewith the reject obtained with each cleaning process is treated individually and the treated reject is returned to the advancing pulp suspension.
摘要:
There is a need to enhance the bleaching effect achieved when bleaching mechanical and chemithermomechanical pulp with a reductive bleaching agent. This can be achieved with the present invention, which relates to a method for manufacturing bleached mechanical and chemithermomechanical pulp including that lignocellulose material, preferably wood in chip form, is caused to pass through at least one preheater or through a chemical treatment system, a steam separator and a refiner where the lignocellulose material is converted into a pulp suspension which, after steam separation, is passed at least to a storage vessel (latency chest) and to a screening department, from which the major part of the pulp suspension is taken out as a substantially finished product or is taken out and passed to further treatment steps. The reductive bleaching agent is added to the advancing pulp suspension without the use of a bleaching tower or the like. The method is characterized by adding the bleaching agent at a location downstream of the refiner and upstream of the screening department, and by bleaching the pulp under the given drastic condition from the aspect of temperature and the given minimized oxygen access at said location and immediately downstream of said location.