Performance and characteristics of a nitritation air-lift reactor under long-term HRT shortening

Xylitol is an organic, non-toxic, biosourced phase change material with high potential for seasonal thermal energy storage material. It has a high energy density, a high and stable undercooling allowing storing solar energy at ambient temperature thus, reducing thermal losses and the risk of spontaneous nucleation (i.e., the risk of losing the stored energy). When the energy is needed, the discharge triggering of the storage system (i.e., Nucleation triggering of highly viscous undercooled Xylitol) is very difficult as well as reaching a sufficient power delivery (i.e., the control of the subsequent crystal growth rates). Both are the mains locks for the use of Xylitol in seasonal energy storage. Different techniques to crystallize highly undercooled Xylitol have hence been considered. It has been proven that nucleation triggering of highly undercooled Xylitol using an air lift reactor would allow reaching performances matching with building applications (i.e., at medium temperatures, below 100 °C). The advantages of this technique compared to other existing techniques to activate the crystallization are discussed. The mechanisms triggering the nucleation are investigated. The air bubble generation, transportation of nucleation sites and subsequent crystallization are discussed to improve the air injection operating conditions.

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An experimental study of the minimum fluidization velocity in a three-phase external-loop air-lift reactor

Chemical Engineering Science ◽

10.1016/0009-2509(88)85076-0 ◽

1988 ◽

Vol 43 (5) ◽

pp. 1161-1165 ◽

Cited By ~ 14

Author(s):

Duško Pošarac ◽

Dragan Petrović

Keyword(s):

Experimental Study ◽

Minimum Fluidization Velocity ◽

Fluidization Velocity ◽

External Loop ◽

Minimum Fluidization ◽

Three Phase ◽

Air Lift Reactor ◽

Air Lift

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Studies on Microbial Leaching of Heavy Metals from Municipal Sludge

Water Science & Technology ◽

10.2166/wst.1990.0117 ◽

1990 ◽

Vol 22 (12) ◽

pp. 229-238 ◽

Cited By ~ 22

Author(s):

R. D. Tyagi ◽

D. Couillard ◽

F. T. Tran

Keyword(s):

Ammonia Nitrogen ◽

Filter Press ◽

Vacuum Filter ◽

Continuous Stirred Tank Reactor ◽

Microbial Leaching ◽

Anaerobically Digested Sludge ◽

Air Lift Reactor ◽

Solid Liquid ◽

Air Lift ◽

Metal Solubilization

A comparative study between continuous stirred tank reactor (CSTR) with cell recycle and air-lift reactor was carried out in 30 1 capacity reactors for metal solubilization from anaerobically digested sludge. In CSTR at a residence time of 0.75 day, supplementing the feed sludge with 4 g/l of FeSO4.7H2O, using 20% sludge recycle and adjusting pH of the feed sludge to 4.5 resulted in following metal solubilization : 91% Cu, 94% Zn,, 93% Mn, 67% Cd, 67% Ni, 8% Cr, and 7% Pb. At 0.75 day retention time metals were solubilized to the recommended level in CSTR as well as in air-lift reactor. The treated sludge is easy to filter in plates filter press, centrifugation, or vacuum filter. The sludge nutrients do not seem to be diminished as a result of treatment and separation of solid-liquid. The ammonia-nitrogen fraction seems to be transformed in organic nitrogen. The decontaminated sludge produced has less odour.

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Development and Scale-Up of an Aerobic Biofilm Air-Lift Suspension Reactor

Water Science & Technology ◽

10.2166/wst.1993.0505 ◽

1993 ◽

Vol 27 (5-6) ◽

pp. 253-261 ◽

Cited By ~ 31

Author(s):

J. J. Heijnen ◽

M. C. M. van Loosdrecht ◽

R. Mulder ◽

R. Weltevrede ◽

A. Mulder

Keyword(s):

Aerobic Oxidation ◽

Scale Up ◽

Suspended Particles ◽

Aerobic Treatment ◽

Treatment Concept ◽

Air Lift Reactor ◽

Volumetric Loading ◽

Air Lift ◽

Sludge Production

A new aerobic treatment concept for the aerobic oxidation of COD, ammonia and sulphide has been developed. The concept is based on the formation of biofilms on small suspended particles in an air-lift reactor. This reactor concept enables to combine a low sludge loading with a high volumetric loading. This makes the reactor especially useful for e.g. nitrification processes. It is also feasible to operate under conditions of marginal sludge production. In this article the scale up aspects of such a process are discussed.

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