Abstract: Device for taking a filtrate sample from fibrous slush pulp through the wall (2) of a container (1) containing pulp, said device comprising a cylinder (3) mounted on the wall (2) so that it goes through the wall, with its open end (5) towards the container (1); a piston (7) placed in the cylinder space and forming a sampling duct (8) from the open cylinder end into the cylinder space behind the piston; and an actuator (9) for moving the piston into an intermediate position, in which the piston end forms a pocket (10) limited by the cylinder walls (4) and the piston end for gathering fibrous slush pulp and forming a pillow-like filter (11) in the pocket, and into a front position for removing the pillow-like filter into the container; the cylinder is provided with a drain duct (12) for draining off the sample penetrating through the filter and the sampling duct into the space behind the piston for analysis.

Abstract: In the method of the invention, a microwave signal is passed through a material whose moisture content is to be measured, the change in the velocity of the signal which has travelled through the material is measured and the moisture content is determined on the basis of the measured change and a known interdependence between the changes in the microwave signal velocity and the moisture content of the material. The apparatus comprises a transmitting device (1) which transmits a microwave signal through the material to be measured, and a detecting device (2) and a counting device (3) which measure the change of velocity of the signal transmitted through the material and determine the moisture content of the material on the basis of a known interdependence of the change of velocity of the microwave signal in question and change of moisture content of the material.

Abstract: A procedure for determining the composition of a wood chip mix dispensed in alkaline delignifying processes, particularly in sulphate and soda/anthraquinone cooking, with the aid of the monomeric compounds produced in connection with the cooking and dissolved in the waste liquor. As taught by the procedure, a cooking liquor sample is taken in the cooking process, this sample being chromatographically analyzed. On the basis of the content proportions of certain compounds analyzed by substance groups, the composition of the dispensed wood chip mix is determined, and at the same time information is gained for optimating the conditions applied in the cooking process.

Abstract: A procedure for monitoring alkaline delignification, in particular kraft cooking, of wood or other cellulosic material with the aid of the mutually relative concentrations of the monomeric lignin hydration products which are formed in connection therewith and are dissolved in the spent liquor. According to the procedure, a sufficient number of representative spent liquor samples is taken during the cooking process which are analyzed by gas chromatography. On the basis of the concentration proportions of certain compounds which have been analyzed, that time period is determined in each instance which is required to reach the desired degree of delignification.