Abstract: An apparatus for detecting a change in the amount of liquid in a storage tank. The apparatus comprises a vertical upright standpipe for filling with a liquid to a level that generates a hydrostatic head pressure substantially equivalent to that exerted by the liquid in the storage tank; a sensor for sensing hydrostatic head pressure differential between the liquid in the storage tank and the liquid in the standpipe; a connector for connecting the standpipe to the pressure differential sensor, the standpipe connector being substantially horizontally disposed to the standpipe; and a connector for connecting the storage tank to the pressure differential sensor, the storage tank connector being substantially horizontally disposed to the storage wherein the standpipe connector and the tank connector are in substantial axial alignment with each other. Any change in the liquid pressure in the tank as a result of leakage from the tank will change the differential pressure measured by the pressure transducer.

Abstract: A liquid leak detector for use with above-ground storage tanks. The liquid leak detector includes a vertically upright standpipe for filling with a liquid to a level that generates a hydrostatic head pressure substantially equivalent to that exerted by the liquid in the storage tank; a first pipe connected to the standpipe at about the bottom end thereof and adapted to be connected to the tank at about the bottom of the tank; a pressure transducer disposed within the first pipe for sensing hydrostatic head pressure differential between the liquid in the storage tank and the liquid in the standpipe to determine a change in pressure differential resulting from a change in the amount of liquid in the storage tank; and a hose connected above the level of the liquid in the standpipe and adapted to be connected to the tank above the level of the liquid in the tank.

Abstract: A liquid leak detector for above-ground tanks includes an upright standpipe connected to the tank so that the standpipe can be filled with liquid from the tank to the same level as the liquid in the tank. A pressure transducer is connected between the bottom of the tank and the bottom of the standpipe to measure the difference in pressure of the liquids in the tank and standpipe. Any change in the liquid pressure at the bottom of the tank as a result of leakage from the tank will change the pressure differential on the pressure transducer. This changes the output of the transducer which can be recorded to indicate leakage from the tank.

Abstract: A liquid leak detector for above-ground tanks includes an upright standpipe connected to the tank so that the standpipe can be filled with liquid from the tank to the same level as the liquid in the tank. A pressure transducer is connected between the bottom of the tank and the bottom of the standpipe to measure the difference in pressure of the liquids in the tanks and standpipe. Any change in the liquid pressure at the bottom of the tank as a result of leakage from the tank will change the pressure differential on the pressure transducer. This changes the output of the transducer which can be recorded to indicate leakage from the tank.

Abstract: Process and apparatus are provided for blending a fuel which includes a No. 2 fuel oil component and a No. 1 fuel oil component, with the No. 1 fuel oil component being added to provide a fuel mixture which will not freeze or form solid wax particles above a predetermined temperature. The process includes lowering a temperature of a sample of the No. 2 fuel oil component, detecting a change in wax crystal concentration of the No. 2 fuel oil component sample by detecting a predetermined rate of change in viscosity of the sample or by detecting a predetermined viscosity level of the sample as the temperature thereof is lowered, and measuring a temperature of the No. 2 fuel oil component or bath in which it is cooled, when the change in wax crystal concentration is detected. A percentage amount of the No. 1 fuel oil component to be mixed with the No.

Abstract: An on-site tailored fuel blending process and apparatus is provided for optimizing the blend ratio of a No. 2 fuel oil component and a No. 1 fuel oil component to obtain a fuel mixture which will not freeze, i.e., form wax particles, above a predetermined temperature. Radiant energy, e.g., in the infrared range, from an energy source is transmitted through the sample, and a change in wax crystal concentration of the sample is detected by sensing a predetermined intensity level transmitted by the energy source after the radiant energy therefrom has passed through the sample, or by sensing a predetermined rate of change in the intensity level of the radiant energy after transmission through the sample. The temperature of the sample is measured when the predetermined intensity level or abrupt change thereof is detected. A percentage amount of the No. 1 fuel oil component to be mixed with the No.