Method and plant for the production of material boards and a material board

Method according to any one or more of the preceding claims, characterized in that, in the case of unsaturated air or a steam-air mixture, the dew point is set such that the moisture contained in the fluid (5) condenses in the press mat (1) only after entering the covering layer (2) or after passing through a covering layer (2).

Method according to any one or more of the preceding claims, characterized in that a limit temperature and/or a water content is reached in the middle layer (3) which is suitable for effecting curing of the binder, preferably until the material board emerges from the injection press (20).

Method according to any one or more of the preceding claims, characterized in that a pressing pressure of more than 2 N/mm2 is applied to the press mat (1) in the double belt press (10) and preferably the pressing pressure does not exceed 6 N/mm2.

Method according to any one or more of the preceding claims, characterized in that a cured cover layer (2), after leaving the double belt press (10), has a thickness of more than one mm, preferably of more than 2 mm and most preferably of 3 mm to 4 mm.

Method according to any one or more of the preceding claims, characterized in that liquid and/or hardener for the binder is applied to the surface side of the press mat (1) or an anti-caking agent is applied to a steel belt (12) and/or to a surface side of the press mat (1).

Method according to the preceding claim, characterized in that the thickness of the cured cover layer (2) is determined after the press mat (1) has emerged from the double belt press (10), preferably using a non-destructive testing method, and most preferably the values are used in a control or regulation system for adjusting the double belt press (10) or the thickness of the cover layer (2).

Method according to any one or more of the preceding claims, characterized in that in the injection press (20) the press mat (1) is subjected to a surface pressure of less than 1 N/mm2, preferably less than 0.6 N/mm2 and very particularly preferably to a pressure of less than 0.5 N/mm2.

Method according to any one or more of the preceding claims, characterized in that flat injection plates (21) and/or perforated rollers with covers for areas not facing in the direction of the press mat (1) are used for introducing the fluid (5) into the press mat (1), with openings for guiding and discharging the fluid.

Method according to any one or more of the preceding claims, characterized in that the fluid is introduced into the press mat (1) at a pressure of more than 0.5 bar, preferably of about 1.5 bar, most preferably of more than 2 bar, and/or emerges from the injection plates (21).

Method according to any one or more of the preceding claims, characterized in that the press mat (2) is guided through the injection press (20) with at least one permeable belt (22) resting on one surface side for the passage of the fluid (5), wherein the belt (22) is preferably designed as a perforated metal or plastic belt, as a woven belt or as a chainmail belt.

Method according to any one or more of the preceding claims, characterized in that the belts (22) together with the press mat (1) are compressed in the injection press (20) in the transport direction (8) upstream of the injection press (20) by a compression unit (27) or a calender (25) and/or are subjected to a thrust force in the transport direction (8), preferably by the calender (25) or the drive rollers (24).

Method according to any one or more of the preceding claims, characterized in that, after curing of the middle layer (3), the material board (4) is compressed and/or held in a calibration press (30) between two steel belts (28) to the nominal dimension, preferably with a pressure of less than 2.5 N/mm2.

Method according to any one or more of the preceding claims, characterized in that the cover layers (2) of the material board (4) are smoothed, heated and/or cooled in the calibration press (30).

Method according to any one or more of the preceding claims, characterized in that the waste heat extracted in the calibration press (30) as a result of a cooling process is reused, preferably in a heat pump, a heat exchanger or in other low-temperature appliances, wherein the waste heat is used particularly preferably in parts of the plant in the transport direction (8) upstream of the calibration press (30).

Method according to any one or more of the preceding claims, characterized in that the material boards (4) are produced with a nominal thickness of more than 8 mm, preferably more than 30 mm and most preferably more than 60 mm, wherein solid material boards of up to 80 mm are preferably produced.

Method according to any one or more of the preceding claims, characterized in that after the injection press (20) or uncured press mats (1) are disposed of in a discharge container (7).

Method according to any one or more of the preceding claims, characterized in that the press mat (1) is subjected to pre-compression in a prepress (6) for deaeration before entering the double belt press (10), preferably there with at least one air-permeable fabric belt and most preferably not tempered.

Method according to any one or more of the preceding claims, characterized in that the material board (4) cured in the injection press (20) or emerging from the injection press (20) is subjected to a tractive force in the production direction, preferably by the drive rollers (24) of the injection press (20), by the calibration press (30) or by a separate calender (25).

Method according to any one or more of the preceding claims, characterized in that the speed of the production or of the individual plant parts, preferably of the double belt press (10), the injection press (20) and/or the calibration press (30), is controlled or regulated in a master-slave system by a control or regulating device, wherein the injection press (20) or its production speed is preferably used as the master or as the reference variable.

Method according to any one or more of the preceding claims, characterized in that a single-layer or multi-layer, preferably three-layer or five-layer, press mat (1) is used, which is suitable for the production of an MDF, an HDF, a particle board, an OSB (chipboard), a mixed board made of fibers and chips, wherein the fibers are preferably arranged in the outer layers, or a thermal insulation board.

Method according to any one or more of the preceding claims, characterized in that at least proportionally aminophenol-based binders, methylene diphenyl isocyanate (MDI), polymeric methylene diphenyl isocyanate (pMDI), urea-formaldehyde resins (UF), melamine-reinforced urea-formaldehyde resins (MUF), melamine-formaldehyde resins (MF), bio-based resins, preferably tannins with mixed polymers, vegetarian and/or animal proteins, lignins with mixed polymers, carbohydrate-containing binders, PVA, acrylic and/or epoxy-based resins can be used as the curable binder in the press mat (1).

Method according to any one or more of the preceding claims, characterized in that the press mat (1) or the uncured middle layer (3) is aerated or springs back in a decompression area (17) after leaving the double belt press (10), wherein a tempered fluid (5) is made available in this decompression area (17) to the press mat (1) on at least one surface side and/or the narrow sides for incorporation into the press mat (1).

Method according to any one or more of the preceding claims, characterized in that the press mat (1) is compressed after the double belt press (10) in a compression area (18), preferably on the inlet side in the injection press (20),

• wherein the tempered fluid (5) of the press mat is preferably injected on at least one surface side in this compression area (18) and/or is passively picked up or extracted on one, most preferably on the opposite, surface side.

Method according to any one or more of the preceding claims, characterized in that the press mat material comprises pure and/or mixtures of lignocellulosic materials, such as natural wood, recycled wood, woody plants, waste wood, plant residues and/or annual plants, whereas preferably filler materials can be added.

Plant for the continuous production of material boards from at least one material which is spread to form a flat mat of press material and which is mixed with at least one binder which can be cured by heat and/or pressure, whereas the mat can be spread as a one or multi horizontally stratified mat, characterized in that a double belt press (10) with two endlessly circulating steel belts (12) for compressing and/or heating the press mat (1) and for at least partially curing a cover layer (2) resting against a steel belt (12) by heating to above the curing temperature of the binder is arranged in the transport direction (8) of the press mat (1), and an injection press (20) having at least one means for injecting tempered fluids (5) into one of the surface sides of the press mat (1) for tempering and curing the uncured parts of the mat or the middle layer (3) is arranged downstream of the double belt press (10).

Plant according to the preceding claim, characterized in that injection plates (21) or injection nozzles are arranged as means for injecting tempered fluids (5), preferably with openings for providing preferably heated air, steam, superheated steam and/or a steam-air mixture over a large area.

Plant according to any one of the preceding plant claims, characterized in that an anti-caking agent applicator (15) for applying an anti-caking agent to a steel belt (12) of the double belt press (10) or to the press mat (1) and/or an additive application (16) for applying additives and/or water to the press mat (1) is arranged upstream of the double belt press (10).

Plant according to any one of the preceding plant claims, characterized in that one or two endlessly circulating belts (22) are arranged in the injection press (20), preferably a perforated metal or plastic belt, a woven belt or a chainmail belt.

Plant according to any one of the preceding plant claims, characterized in that a compression unit (27) and/or a calender (25) is arranged in or adjacent to the injection press (20).

Plant according to any one of the preceding plant claims, characterized in that a calibration press (30) and/or a discharge container (7) is arranged downstream of the injection press (20) and/or a discharge container (7) is arranged downstream of the calibration press (30).

Plant according to any one of the preceding plant claims, characterized in that the calibration press (30) is arranged with a heating and/or a cooling system for the mat respectively the board and is preferably operatively connected to a low-temperature appliance for recycling waste heat from the material boards (4), preferably to a heat exchanger, a heat pump and/or parts of the plant upstream of the calibration press (30).

Plant according to any one of the preceding plant claims, characterized in that a decompression area (17) having a chamber (9), a tunnel, an enclosure and/or injection plates is arranged between the double belt press (10) and the injection press (20) to provide tempered fluids (5) for the press mat (1), which increases in volume.

A material board, preferably produced by a method according to any one or more of the preceding method claims and/or produced in a plant according to any one or more of the preceding plant claims.