Scrubbing ammonia

Ammoniak-rest, m. ammonia residue (amidogen, NH2). -rohr, n. ammonia tube or pipe, -salpeter, m. ammonia saltpeter (ammonium nitrate), -salz, n. ammonium salt, -selfe,/. ammonia soap, -soda, /. ammonia soda, Solvay soda, -stickstoff, m. ammonia nitrogen. -verbindung, /, ammonia compound ammonium compound, -verfahren, n. ammonia process, -wasche, /. ammonia scrubbing ammonia recovery plant, -wascher,... 

You are given experimental data for an absorption system to be used for scrubbing ammonia (NH3) fi om air with water. The water rate is 300 Ib/min and the gas rate is 250 Ib/min at 72°F. The applicable equilibrium data for the ammonia-air system is shown in the following table (R. H. Perry and D. W. Green, Ed., Perrys Chemical Engineers Handbook, 7th Edition, McGraw Hill, New York, 1996.)... 

Example 1.3-1 Ammonia scrubbing Ammonia, the major material for fertilizer, is made by reacting nitrogen and hydrogen rmder pressure. The product gas can be washed with water to dissolve the ammonia and separate it from other unreacted gases. How can you correlate the dissolution rate of ammonia during washing ... 

We are interested in how a first-order chemical reaction alters the mass transfer in industrial equipment. For example, imagine that we are scrubbing ammonia out of air with water, using equipment like that shown in Fig. 10.2-1. To increase our equipment s capacity, we are considering adding small amounts of hydrogen chloride to the water. We want to predict the effect of this acid. However, the a-priori prediction of mass transfer in a scrubber is a tremendously difficult problem, requiring expensive numerical calculation. 

Another method for removing O2 is to pass the nitrogen through a long tightly packed column of Cu turnings, the surface of which is constantly renewed by scrubbing it with ammonia (sg 0.880) soln. The gas is then... 

In many cases, water is a poor scrubbing solvent. Sulfur dioxide, for example, is only slightly soluble in water, so a scrubber of very large liquid capacity would be required. SO2 is readily soluble in an alkaline solution, so scrubbing solutions containing ammonia or amines are used in commercial applications. 

Particulate emissions from zinc processing are collected in baghouses or ESPs. SO2 in high concentrations is passed directly to an acid plant for production of sulfuric acid by the contact process. Low-concentration SO2 streams are scrubbed with an aqueous ammonia solution. The resulting ammonium sulfate is processed to the crystalline form and marketed as fertilizer. 

On molybdenum sulfate roasting, downstream of a scrubber, to remove ammonium sulfite and sulfate aerosols which form in the ammonia scrubbing stage, and SO2,... 

A gaseous emission is to be treated for the removal of ammonia. Table 9.4 provides the stream data. Two scrubbing agents are considered for the removal of ammonia, water, Si, and an inm anic solvent, S2. The absorption of ammonia in water is coupled with the following chemical reaction ... 

The solution involves the use of two water substreams for scrubbing at 293 and 298 K. The first coolant is employed to undertake the cooling duty. Several conceptual flowsheets can be developed to implement this solution. Figures 9.18a and b illustrate such configurations. The developed mass exchanger is composed two sections. The top section employs Si,3 to reduce the ammonia composition in the gas from 0.13% to 0.10% and operates at an average water temperature of 293 K. In Fig. 9.18a, temperature is reduced by indirect contact cooling of the... 

In a packed column, operating at approximately atmospheric pressure and 295 K, a 10% ammonia-air mixture is scrubbed with water and the concentration of ammonia is reduced to 0.1%. If the whole of the resistance to mass transfer may be regarded as lying within a thin laminar film on the gas side of the gas-liquid interface, derive from first principles an expression for the rate of absorption at any position in the column. At some intermediate point where the ammonia concentration in the gas phase has been reduced to 5%. the partial pressure of ammonia in equilibrium with the aqueous solution is 660 N/nr and the transfer rate is ]0 3 kmol/m2s. What is the thickness of the hypothetical gas film if the diffusivity of ammonia in air is 0.24 cm2/s ... 

Steel Coke-oven gas scrubbing operation Ammonia, sulfides, cyanides, phenols... 

Recent years, the authors have innovatively proposed a method by using the aqueous ammonia liquor containing hexamine cobalt (II) complex to scrub the NO-containing flue gases[6-9], since several merits of this complex have been exploited such as (1) activation of atmospheric O2 to a peroxide to accelerate the O2 solubility, (2) coordination of NO, as NO is a stronger ligand than NH3 and H2O of Co( II) complexes to enhance the NO absorption and (3), catalysis of NO oxidation to further improve the absorption both of O2 and NO. Thus, a valuable product of ammonium nitrate can be obtained. 

Continuing further with the recovery aspects from coke oven gas reference may be drawn to the recovery of light oil (crude benzol). In a typical process used, the coke oven gas (from which benzol is to be recovered) after removal of tar, ammonia etc. is passed through the benzol scrubber where the benzol vapours are scrubbed by wash oil flowing countercurrent to the gas. Benzolised wash oil is then pumped to the recovery section where the crude benzol, absorbed in the wash oil is stripped off by steam. The steam vapour mixture, com-... 

When HDT is a feed pretreatment for HCK, the unit could consist of one or two reactors, with or without intermediate scrubbing. The use of zeolitic-noble metal catalysts imposes careful scrubbing of ammonia and H2S prior to the corresponding HCK reactor. 

Scrubbing the loaded organic phase with water or ammonia removes HC1, transferring the copper to the pH-swing extractant, e.g., as in,... 

Scrubbing this loaded organic solution with aqueous ammonia triggers the transfer of the zinc to the acidic extractant L H,... 

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