摘要:
A flocculating agent for use in water purification technology and papermaking technology is described, as well as a process of producing the flocculating agent which is the reaction product of sulphate ion-containing polymeric aluminium hydroxy chloride and one or more cationic polymers preferably selected among polyacrylic amide, polyamide amine and polyethylene imine. The most preferred cationic polymer is polyacrylic amide. The flocculating agent is produced by mixing an aqueous suspension of sulphate ion-containing aluminium polyhydroxy chloride having a solids content of 20-30 parts by weight with 0.3-60 parts by weight of cationic polymer, based upon 100 parts by weight of sulphate ion-containing aluminium polyhydroxy chloride, and by heating the mixture for 2-4 h at a temperature varying from about 80.degree. C. to the boiling point of the mixture.
摘要:
A method of determining distances and angular positions of stationary and moving objects (3), for example in an area to be monitored in connection with for instance swing doors. The determination is done by means of triangulation where light, which in the main part is collimated, is transmitted (1) into the area at different angles and in a certain sequence. The reflected light is correspondingly registered on a position-sensitive sensor (5) which is positioned at a certain distance from the transmitter (1). The position (5a, 5b), where the reflected light falls on the sensor (5), represents the distance, and the moment when the light is received represents the angular position of the detected object. The values are compared to stored reference values which change when the angle of the door's opening is changed.
摘要:
A process of producing a flocculating agent useful for water purification technology and as a substitute for aluminium sulphate in the rosin sizing of paper is described. In this process, about 100-150 parts by weight, preferably about 130 parts by weight of hydrochloric acid, calculated as 100% HCl, and 140-200, preferably 160-190 parts by weight of a sulphate-containing, aluminium hydroxide-containing sludge, calculated on the solids content of the sludge, are mixed. To obtain the sludge, alkaline pickles used in the pickling of aluminium profiles in connection with the anodization of aluminium are neutralized with sulphuric acid or aluminium sulphate. The sludge may also contain up to about 10% by weight of aluminium hydroxide. The mixture is heated and stirred at a temperature of from about 80.degree. C. to the boiling point of the mixture, preferably 95.degree.-100.degree. C., for a combined time of about 3-15 hours, preferably about 4-6 hours. The reaction product is a substantially saturated aqueous solution of polyaluminium chloride having the presumed formulaAl.sub.a (OH).sub.b (SO.sub.4).sub.c Cl.sub.3a-b-2cwherein a, b and c may have the values 13, 34 and 1, respectively.