In processes of low-pressure (also called 'non-pressure') agglomeration, the condition to satisfy, necessary for binding the fine-grained particles into a bigger agglomerate is bringing them close enough for the action of binding forces. For the purpose of the tests, a mixture of materials was used, produced and prepared in a production plant of a Polish producer of agrochemicals for agriculture and horticulture, i.e. Intermag from Olkusz. The variable input parameters in the tests of the process of non-pressure agglomeration were: inclination angle of the pelleting plate; inclination angle of the blade in the plate pellet mill; rotational speed of the pelleting plate; mass of the water added to the plate during the process and time of the deposit of material staying in the pellet mill. Increasing the amount of pelleting liquid added to the plate results in an increase of the hydraulic diameter of pellets, whereas increasing the inclination angle of the pelleting plate results in the reduction of the hydraulic diameter of pellets. The hydraulic diameter of pellets increases along with the time of the material staying in the pellet mill. The increase of rotational speed of the pelleting plate has an impact on the increase of the hydraulic diameter of pellet particles. The use of the pelleting blade inclined in the plate at an angle of 60° and 90° has an impact on the increase of the hydraulic diameter of pellet particles.