Dry injection

The Dravo hydrate addition at low temperature process involves a two-step injection of water and dry sorbent in a rectangular 19.8-m duct having a cross section of 2 m. In one step water is injected through atomization nozzles to cool the flue gas from 150°C to approximately a 15°C approach to adiabatic saturation. The other step involves the dry injection of hydrated lime, either downstream or upstream of the humidifica tion nozzles. Typical SO2 removals were 50—60% at a Ca S ratio of 2. 

Of the three categories, the packed column is by far the most commonly used for the absorption of gaseous pollutants. Miscellaneous gas-absorption equipment could include acid gas scrubbers that are commonly classified as either wet or diy. In wet scrubber systems, the absorption tower uses a hme-based sorbent liquor that reacts with the acid gases to form a wet/solid by-product. Diy scrubbers can be grouped into three catagories (1) spray diyers (2) circulating spray diyers and (3) dry injection. Each of these systems yields a diy product that can be captured with a fabric filter baghouse downstream and... 

Kagkadis, K. A., Rekkas, D. M., Dallas, P. P., Choulis, N. H. A freeze-dried injectable form of ibuprofen Development and optimization using respond surface methodology. PDA Journal of Pharmaceitical Science Technology, 50 (5), p. 317-323, 1996... 

I.R. Last and K.A. Prebble, Suitabihty of near-infrared methods for the determination of moistnre in a freeze-dried injection prodnct containing different amonnts of the active ingredient, J. Pharm. Biomed. Anal., 11(11/12), 1071-1076 (1993). 

The NORIT Porta-Powdered Activated Carbon (Porta-PAC) dry injection system pneumatically conveys an adjustable amount of powdered activated carbon (PAC) from bulk bags into the flue gas streams of incinerators for mercury and dioxin emission reductions. PAC is metered using a volumetric feeder into a pneumatic eductor where moving air transfers the carbon to the injection point. A series of interlocks control the operation of the unit and allow local or remote operation and monitoring of the unit. This technology is commercially available. All information is from the vendor and has not been independently verified. 

Jones, J.A., Last, I.R., MacDonald, B.F. and Prebble, K.A. (1993) Development and transfer-ability of near-infrared methods for determination of moisture in a freeze-dried injection product /. Pharm. Biomed. Anal. 11, 1227-1231. 

Parson, E.L. Boscak, V. Brna, T.G. Ostop, R.L. "S02 Removal by Dry Injection and Spray Absorption Techniques", presented... 

B. Shemwell, Y. A. Levendis, and G. Simons, Laboratory study on the high temperature capture of HCl gas by dry-injection of calcium-based sorbents, Chemo-sphere, 42, 785-796 (2001). 

Last and Prebble [51 ] developed a near-infrared reflectance (NIR) method for the determination of moisture in an experimental freeze-dried injection product. NIR spectra were collected through the bases of unopened product vials using a horizontal instrument accessory. The samples in these vials were then used for Karl Fischer analysis to generate a standard curve for the analysis. The NIR data must be correlated with an accepted residual moisture technique in order to yield a meaningful result. This article states that NIR accuracy and precision in this application are not consistent with allowing the use of the current method in anything but a screening role. 

The dry injection technique is often used in normal-phase flash chromatography when the solubility of the compound in a mobile phase is low. In this technique, a suspension of silica in the sample solution is concentrated to dryness and placed in a separate precolumn introduced before the actual column. In the reversed-phase mode, when there is limited sample solu-... 

Fig. 9 Integrated dry injection process utilizing both calcium hydroxide and sodium bicarbonate to reduce sulfur dioxide and nitrogen oxide emissions. Calcium hydroxide is added to the hot flue gases before they are cooled in the economizer and combustion air heater, while sodium bicarbonate is added to the cooled gases before they enter the electrostatic precipitator. (From Ref. l)...

HI-6 as a powder is excellent (estimated shelf life at 25°C of 73 years), but HI-6 has extremely poor stability in solution. For this reason, a number of wet/dry injection devices have been developed, which have the advantage that by separating the solid drug from the liquid vehicle the stability is markedly increased. However, the disadvantage is that it is necessary to dissolve the drug in the vehicle before it can be injected and this may involve a delay in administering the drug. HI-6 methanesulphonate is much more rapidly soluble than HI-6 dichloride (Krummer el al., 2002). 

Bohrer D, do Nascimento PC, Ramirez AG, Mendonca JKA, de Cavalho LM, Pomblum SCG, Determination of thiamine in blood serum and urine by high-performance liquid chromatography with dried injection and post-column derivatization. Microchem J 2004 28 71-6. 

Calcium silicate - board 29.4 High-temperature dry injection... 

Mercury and cadmium are more volatile (boiling points 356 and 765 °C respectively) and are consequently more difficult to remove. They are reduced to about 0.2mg/Nm in total in the semi-dry scrubbing and pre-cooled dry injection processes and to about 0.1 mg/Nm in the wet scrubbing processes [29.10]. Where lower emission levels are required, the injection of activated carbon can reduce the level to 0.05 mg/Nm [29.10]. 

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