摘要:
Es wird ein Verfahren zum Steuern und/oder Regeln eines Prozessluftsystems einer einem Trockenzylinder, insbesondere Yankeezylinder, zugeordneten Trockenhaube, insbesondere Yankeehaube, einer Maschine zur Herstellung einer Faserstoffbahn, insbesondere Papier-, Karton- oder Tissuebahn beschrieben, bei dem einem Nassteil und einem Trockenteil der Trockenhaube jeweils heiße Zuluft aus einem Brenner zugeführt wird, Rückluft aus dem Nassteil und Rückluft aus dem Trockenteil der Trockenhaube jeweils zu dem betreffenden Brenner zurückgeführt wird, Abluft aus dem Nassteil und Abluft aus dem Trockenteil der Trockenhaube jeweils einem Wärmetauscher zugeführt wird, die aus dem Wärmetauscher wieder austretende Abluft über ein Abluftgebläse an die Umgebung abgeführt wird und durch den Wärmetauscher vorgewärmte Frischluft dem dem Nassteil der Trockenhaube zugeordneten Brenner und dem dem Trockenteil der Trockenhaube zugeordneten Brenner zugeführt wird, jeweils die Feuchte der Rückluft aus dem Nassteil und die Feuchte der Rückluft aus dem Trockenteil der Trockenhaube gemessen wird, in Abhängigkeit von der Feuchte der Rückluft aus dem Trockenhaubenteil mit der relativ höheren Wasserverdampfung der Durchfluss des Abluftgebläses gesteuert wird und die durch das Verhältnis von zugeführtem zu abgeführtem Luftmassenstrom bestimmte Luftbilanz des Nassteils und/oder des Trockenteils der Trockenhaube über die Zufuhr an vorgewärmter Frischluft aus dem Wärmetauscher zu dem dem Nassteil bzw. Trockenteil der Trockenhaube zugeordneten Brenner auf einen vorgebbaren Sollwert geregelt wird. Es wird auch eine entsprechende Vorrichtung zur Durchführung des Verfahrens beschrieben.
摘要:
The invention relates to a method and arrangement for stabilising operation of an impingement dryer (1) in a paper or board machine or the like. The method comprises arranging air to be heated to enter a burner chamber (4) of the impingement (1) dryer through an air inlet opening (11) of the burner chamber (4), the air entering in an angle in relation to at least one burner head (7) in the burner chamber (4), the burner head (7) having a flame opening (8) in its first end, heating air in the burner chamber (4) by bringing the air into a contact with a flame (9), and transferring heated air from the burner chamber (4) to blowing members of the impingement dryer (1). Between the air inlet opening (11) of the burner chamber (4) and the flame opening (8) of the at least one burner head (7) is arranged, in the direction of the air flow, a guiding member (13) comprising at least one aperture, and the air flow, which enters through the air inlet opening (11) of the burner chamber (4) is divided so that a first air flow (14) travels through the at least one aperture of the guiding member (13) and a second air flow (15) travels through a gap (16) formed between the guiding member (13) and the burner head (7).
摘要:
The invention pertains to a paper or board making machine for manufacturing high filler content paper or board and to a corresponding method. The paper or board making machine comprises a forming section (101) in which at least one wire (105) arranged in a wire loop is provided for forming a web (W) from a fiber suspension, a closed draw press section (102) in which at least two press nips (N, N) being formed between two rolls (118, 119) each are provided for dewatering the web (W) transferred from the forming section (101), and a drying section (103) in which at least one drying cylinder (132) is provided for drying the web (W) transferred from the closed draw press section (102). The forming section (101) comprises a headbox (99) being capable of supplying liquids onto the wire (105, 109) in a layered manner and comprising a turbulence generator and a nozzle chamber having two converging walls (21, 22) forming a nozzle outlet (24). The turbulence generator has at least three diffusers (1, 3, 5, 7, 9) creating turbulence in liquids supplied into each respective diffuser (1, 3, 5, 7, 9) via feeding means (25, 27, 29) for feeding pulp suspension and/or water as the liquids. Each of the diffusers (1, 3, 5, 7, 9) has an outlet into the nozzle chamber. A central diffuser (1) of the at least three diffusers (1, 3, 5, 7, 9) has two blades (11, 13) arranged at its outlet and extending into the nozzle chamber in a converging manner. The blades (11, 13) separate a liquid flowing through the central diffuser (1) from liquids flowing through adjacent diffusers (3, 5, 7, 9). In the transporting direction of the web an impingement drying means (123, 124) is arranged before the at least one drying cylinder (132) in the drying section (103).
摘要:
The invention relates to a cleaning device unit for cleaning a filter surface of a fan tower of a pulp dryer. The cleaning device unit comprises movement means for moving a cleaning module along the filter surface, and a cleaning module, which comprises a blow part, which is arrangeable to blow air to the filter surface to be cleaned, and a suction part, which is arranged in the horizontal direction at a distance from the blow part, and which is arrangeable to suck air from the filter surface to be cleaned. The invention also relates to a pulp dryer comprising the cleaning device unit and a method for cleaning the filter surface of a fan tower of a pulp dryer.
摘要:
The invention relates to a drying arrangement and method for a moving web, such as a paper or board web. The arrangement comprises an air dryer (3, 3',3'',3'''), which comprises a first air supply channel (9), which defines a first direction and which extends in a transversal direction of the web to be dried from its first edge toward its second edge. The air dryer also comprises a number of second air supply channels (12), which are arranged in connection with the first air supply channel (9), and into which heated drying air is supplied from the first air supply channel (9), the second air supply channels (12) defining a second direction, which is perpendicular to the first direction and parallel to the travel direction of the web to be dried. The air dryer further comprises elongated blowing means (13, 13', 13''), each of which is arranged in connection with a plurality of second air supply channels (12) for supplying heated drying air from the second air supply channels (2) to the blowing means (13, 13', 13''), the blowing means (13, 13', 13'') being parallel to the first air supply channel (9). A profiling connection (7) has been arranged in connection with at least one, preferably several, second air supply channels (12) for supplying additional air into the second air supply channel (12) in order to change the moisture profile of the web in the transversal direction of the web.