Carbon, activated, odor removal

Other industries of interest are (1) the manufacturing of spices and flavorings, which may use activated carbon filters to remove odors from their exhaust stream (2) the tanning industry, which uses afterburners or activated carbon for odor removal and wet scrubbers for dust removal and (3) glue and rendering plants, which utilize sodium hypochlorite scrubbers or afterburners to control odorous emissions. 

Dacor. [Bamebey Sutcliffe] Activated carbon disposable odor remover. 

H2S or CH the latter always contains associated impurities that have taste and odor. Removal of these gases can be accompHshed by adsorption (qv) with activated carbon (qv) oxidation with chlorine, potassium permanganate, or o2one or aeration. 

Activated carbon An adsorption filter that makes use of an activated carbon bed to remove odors and various gases from a ventilating or gas cleaning system. 

The Prosser olfactometer is a commercially-produced version of the portable olfactometer developed by the Warren Spring Laboratory (WSL) (2). The olfactometer (Figs. 1,2) contains two fans, which draw in ambient air through an activated carbon filter to remove extraneous odours and then mix this odour-free air with an odorous air sample before expelling the mixture through either a sample port (fan 1) or an exhaust port (fan 2) at 240 1/min. 

Room temperature control and adequate venhlation are the most critical factors in designing the panel room. In order to maintain a comfortable temperature in the room, air-conditioning should be installed. A slight positive air pressure should be maintained in the booth area to prevent inhltration of external odors. Individual exhaust ventilation ducts should be located in each booth. Air turnover in the room should occur at least every 30 seconds (1). Recirculated and makeup air should pass through activated carbon filters to remove odors. 

Alternatives most frequently considered for taste and odor removal include breakpoint chlorination, aeration, ozonation, and oxidation with chlorine dioxide or potassium permanganate. None of these technologies have been found to approach the activated carbon adsorption process iri terms of effective treatment for this particular water quality problem. Another alternative is sorption onto other solids such as bleaching clays, synthetic resins or manganese dioxide. A brief summary of the advantages, disadvantages and cost factors associated with adsorption and alternative treatments for removal of tastes and odors... 

One form of carbon is known as activated charcoal. The term activated means that the charcoal has been ground into a very fine powder. In this form, charcoal can remove impurities from liquids that pass through. For example, activated charcoal removes color and odor from oils and water solutions. 

Treated and filtered wastewater can be recycled for use in irrigation. An important issue is odor removal prior to reuse. For a wastewater that has an initial concentration of 10 ppm of these compounds, the following test results are obtained when activated carbon is used to adsorb them ... 

The contribution of activated carbon to improved quality of product is not always fully recognized characteristics such as freedom from haze, absence of foam, and other less visible benefits are often overlooked. It is worth noting that many of these less evident benefits are often a by-product incidental to the use of carbon for color and odor removal—and hence can often be obtained for little if any extra cost. For the most part, all that is ordinarily required is a selection of appropriate operating conditions. 

Caustic activated carbons as hydrogen sulfide odor removal media... 

Varies Odor removal from waste gases (active carbon)... 

Applications. The applications of activated carbons form a large and growing market and are found in color and odor removal, in water purification, toxic-gas removal, general air purification, metal-ion adsorption for metal recovery, decoloration and purification of sugar, pharmacology, and chromatography. 

Principal requirements of carbon for use in odor-removal equipment are a high capacity and low pressure drop. The material must also be dustless.. Specifications for activated carbon used in air purification are presented in Table 12-33. Typical commercial equipment is illustrated in Figure 12-51,12-52, and 12-53. 

Activated carbon. A highly adsorbent form of carbon, used to remove odors and toxic substances from gaseous emissions. In advanced waste treatment, activated carbon is used to remove dissolved organic matter from wastewater. 

Example 15.4-1 Odor removal We have been removing odor from a Miimesota resort s water supply using a bed of activated carbon. The bed s breakthrough is in 38 days, and its exhaustion is in 46 days. Because of seasonal demand, we want to double the water flow through the bed. We suspect that the mass transfer coefficient will be constant. If it is, when will breakthrough occur now ... 

The extent of purification depends on the use requirements. Generally, either intense aqueous extractive distillation, or post-treatment by fixed-bed absorption (qv) using activated carbon, molecular sieves (qv), and certain metals on carriers, is employed to improve odor and to remove minor impurities. Essence grade is produced by final distillation in nonferrous, eg, copper, equipment (66). 

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