The definition of papermaking machinery industry refers to the machinery that includes raw material preparation, pulping, papermaking, until it is made into rolls or flat sheets, and processing paper and cardboard. For more details, the following is the definition and classification of the paper machinery industry compiled by the editor.
Types of papermaking machinery: paper machines include fourdrinier multi-cylinder paper machines, cylinder paper machines, etc. The types of paper machines used vary according to different paper products.
Equipment classification:Material preparation equipment is the equipment for pretreatment and processing of papermaking raw materials according to the requirements of the cooking or refining process before cooking or refining. It is divided into non-wood fiber preparation equipment and wood fiber preparation equipment. The former includes grass cutters, reed cutters and sugarcane decontamination machines, while the latter includes debarkers and chippers.
The chipper is a machine that cuts the logs required for the production of wood pulp into wood chips of a certain specification. It is divided into two types: disc type and drum type; digester is to dissolve the lignin in the papermaking raw materials into the cooking liquor to separate the papermaking raw materials Equipment for fiber is divided into two types: batch type and continuous type; wood grinder is an equipment for producing groundwood pulp. According to the production method, it can be divided into two types: batch type and continuous type. According to the pressing method of logs, it can be divided into two types: Two types of hydraulic pressure and mechanical pressure;
Pulping equipment is the equipment used in the process of separating plant raw materials into fibers. Pulping methods can be divided into chemical method, mechanical method and chemical mechanical method. The corresponding pulping equipment includes digester, wood grinder, heat mill, pulp washer, bleaching machine, beating machine and waste liquid recovery equipment.
After the wood chips are preheated by steam, the slurry that is ground under high pressure is called hot wood chip ground wood pulp. The machine that makes hot wood chip ground wood pulp is the heat mill. The heat mill consumes a lot of power, so it is sufficient Utilizing the heat energy in the refining process is the key issue of the thermal mill; the pulp washing machine is a mechanical equipment that separates the cooked pulp from the black liquor. According to the black liquor extraction rate, there are two categories: high concentration and low concentration extraction.
The purpose of pulp bleaching is to remove the residual lignin and pigments in the pulp after cooking, improve the whiteness of the pulp, and make the pulp have a white color. Bleaching machine is a kind of bleaching equipment commonly used, which is composed of bleaching tank screw propeller, washing drum and other components. The slurry and bleaching agent are placed in the pool and the washing water is continuously added, with the help of the screw propeller to circulate in the pool to complete the process of mixing and chemical reaction. The water with bleaching products and residual bleaching liquid is discharged through the inner cavity of the washing drum, so that a white pulp is obtained.
Paper machine
It is a complete set of equipment linked to the division of the pulp into the paper web, including the headbox, the wire section, the press section, the drying section, the calender, the paper reel, and the transmission section. , Heat recovery and other auxiliary systems. The wire part that forms the wet paper web is the core of the paper machine, so the paper machine can be divided into fourdrinier paper machine, clamp paper machine and cylinder paper machine according to the structure of the wire part.
The headbox is the equipment that sends the slurry of appropriate concentration to the network evenly and stably through the slurry distributor, rectifier, weir pool, weir plate nozzle and other components, also known as the headbox; the slurry is sprayed from the headbox to the copper After the web, a wet paper sheet is formed on the wire and dewatered; after that is pressing, that is, a mechanical method is used to squeeze out the moisture of the wet paper from the wire to increase the dryness of the paper and improve the surface properties of the paper. , Eliminate net marks and increase smoothness, tightness and strength; then enter the drying section to further dehydrate the wet paper sheet after pressing, so that the paper sheet shrinks, the fiber is tightly bonded and the strength is increased.
After the paper sheet from the drying section is calendered by the calender, the smoothness, gloss and tightness of the paper sheet can be improved, the thickness of the whole paper sheet can be uniform, and the air permeability can be reduced. Rolling into a paper roll completes the main process of papermaking. In order to meet different needs in the future, there are super calenders, rewinders, paper cutters, etc. behind the paper reel in the papermaking workshop.
The paper industry consumes a lot of raw materials, water, electricity and chemicals, and produces a lot of waste water and waste residue. Therefore, the future of papermaking machinery will develop in the use of a wide range of papermaking raw materials, reducing material and energy consumption in the papermaking process, and reducing environmental pollution. For more information on the paper machinery industry, please refer to the "2015-2020 China Paper Machinery Industry Development Prospect Forecast Report" released by the China Report Hall.
