Types offracers Over the years, a number of tracers have been used to evaluate the hydraulic performance of reactors. Important characteristics for a tracer include (IThe tracer should not affect the flow (should have essentially the same density as water when diluted) (2 )The tracer must be conservative so that a mass balance can be performed
Types of Tracers Over the years, a number of tracers have been used to evaluate the hydraulic performance of reactors. Important characteristics for a tracer include : (1)The tracer should not affect the flow (should have essentially the same density as water when diluted). (2)The tracer must be conservative so that a mass balance can be performed
(3)It must be possible to inject the tracer over a short time period 4)The tracer should be able to be analyzed conveniently (5)The molecular diffusivity of the tracer should be low (6 The tracer should not be absorbed on or react with the exposed reactor surfaces (The tracer should not be absorbed on or react with the particles in wastewater
(3)It must be possible to inject the tracer over a short time period. (4)The tracer should be able to be analyzed conveniently. (5)The molecular diffusivity of the tracer should be low. (6)The tracer should not be absorbed on or react with the exposed reactor surfaces. (7)The tracer should not be absorbed on or react with the particles in wastewater
Dyes and chemicals that have been used successfully in tracer studies include congo red, fluorescein, fluorosilicic acid (H2SiF6), hexafluoride gas(SF), lithium chloride (LiCD), Pontacyl Brilliant Pink b, potassium potassium permanganate, rhodamine WT and sodium chloride(Nacl). Pontacyl Brilliant pink b( the acid form of rhodamine wt)is especially useful in the conduct of dispersion studies because it is not readily adsorbed onto surfaces
Dyes and chemicals that have been used successfully in tracer studies include congored, fluorescein, fluorosilicic acid (H2 SiF6 ), hexafluoride gas (SF6 ), lithium chloride (LiCl), Pontacyl Brilliant Pink B, potassium, potassium permanganate, rhodamine WT, and sodium chloride (NaCl). Pontacyl Brilliant Pink B (the acid form of rhodamine WT) is especially useful in the conduct of dispersion studies because it is not readily adsorbed onto surfaces
Because fluorescein, rhodamine WT, and pontacyl Brilliant Pink b can be detected at very low concentrations using a fluorometer, they are the dye tracers used most commonly in the evaluation of wastewater-treatment facilities. Lithium chloride is commonly used for the study of natural systems. Sodium chloride, used commonly in the past, has a tendency to form density currents unless mixed Hexafluoride gas(SF6)is used most commonly for tracing the movement of groundwater
◼ Because fluorescein, rhodamine WT, and Pontacyl Brilliant Pink B can be detected at very low concentrations using a fluorometer , they are the dye tracers used most commonly in the evaluation of wastewater-treatment facilities. Lithium chloride is commonly used for the study of natural systems. Sodium chloride, used commonly in the past, has a tendency to form density currents unless mixed. Hexafluoride gas (SF6 ) is used most commonly for tracing the movement of groundwater
Conduct of Tracer Tests Tracer response curve for slug input Slug injection of tracer Mixer to Time disperse tracer UV banks Effluent weir UV channel Stacked plan view of UV channel Continuous injection Time of tracer using positive Tracer response displacement pump curve for continuous input Fig 4-6 Schematic ofsetup used to controltracer studies ofplug-flow reactors (a)slug of tracers added to flow; (b)continuous input of tracer added to flow. Tracer response curve is measured continuousl
Conduct of Tracer Tests Fig 4-6 Schematic of setup used to control tracer studies of plug-flow reactors (a)slug of tracers added to flow; (b)continuous input of tracer added to flow. Tracer response curve is measured continuously