Impinger devices

The second part describes different experimental approaches to simultaneously assess deposition and subsequent absorption of pharmaceutical aerosol formulations, typically by adapting some existing impactor/impinger devices to accommodate pulmonary epithelial cell culture systems. Differences between longtime and low-dose aerosol deposition in environmental toxicology and short time bolus inhalation of pharmaceutical aerosols are elucidated. 

A variety of designs have been developed to maximize the relative motion between particles and spray droplets or the contact between liquid and particles. These include jet impingement devices, packed or sieved plate towers, preformed and gas atomized spray towers, and venturi sprayers. 

A baffle or impingement device is often installed in the center of the chamber to break up the swirling air-water-dust stream. 

Quenching in product oil or in an immiscible hydrocarbon solvent is widely practiced. Orthodox aerosol capture devices such as demisters and other commonly used impingement devices are not very effective and electrostatic precipitation is currently the preferred method. 

Because of the need for standardisation of test equipment, the British Pharmacopoeia and other compendia have adopted detailed specifications for impinger devices. Two impinger devices have been adopted by the British Pharmacopoeia. Apparatus A is shown in Fig. 12.17. All these operate by... 

Knitted wire mesh pads are a common impingement device for removing liquid entminment from vapor or gas stresma. The Otto H. York Cosepany pioneered this concept with the Demister". Several vandors are now active in the field. 

Selecting Nozzles. Nozzle sizes and impingement devices are related by the TEMA rule-of-thumb value of pV2 where p is the shell fluid density and V is the shell fluid velocity at the... 

Impingement devices are often used in tubular equipment to protect the tubes from erosion due to fluid impingement at the shell inlet nozzle. One... 

Inlet Impingement Device The purpose of the inlet impingement device is to diffuse the velocity profile of the fluids entering the reactor inlet nozzle and create an even pattern of liquid dispersion across the top liquid distribution tray. 

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