GB1380544A - Automatic liquid sampler - Google Patents

Abstract

1380544 Sampling liquids SOCNATIONALE DES PETROLES D'AQUITAINE 29 May 1973 [29 May 1972] 25495/73 Heading B8N An apparatus for taking samples of fluid flowing through a pipe or trough 6 comprises a container 3 which is supplied continuously with the fluid to be sampled by a pump 4 and provided with an overflow 7 for returning fluid back to the trough, and a number of sampling vessels 1, 2 each connected through a programme-controlled electrically-operable valve 14 to the suction side of a suction pump 13 which is controlled by a flowmeter 19 responsive to the rate of flow in the trough, the vessels each containing an auxiliary fluid (e.g. air) which is immiscible with, inert to, and less dense than the fluid to be sampled, so that when some of the auxiliary fluid is withdrawn from a vessel by the suction pump, a corresponding quantity of fluid is sucked into the vessel from the container. Twenty-four of such sampling vessels 1, 2 may be disposed around a central container 3 for taking hourly or two-hourly samples under the control of a timer. The suction pump 13 may be a peristalitic one and its flow rate controlled by a mechanism 18 operating in accordance with readings of the flowmeter 19. If sampling is to take place in the open air the vessels 1, 2 are set so as to be in communication with the air through pipes 12 and the valves 14 (see vessel 2). When the valve 14, for example, of the vessel 1 is actuated from the timer 15, the pipe 12 is connected to the suction pump 13 and a sample is withdrawn from the container 3 through a suction tube 9 provided with an aperture 11 above the maximum level to be reached by the sample. The rate of sampling for the vessel 1 is proportional to the rate of flow in the trough 6 and after a set period the valve 14 is again actuated to disconnect the vessel 1 from the suction pump 13 and connect it to atmosphere.