My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in JEQ

  1. Vol. 38 No. 2, p. 647-653
     
    Received: May 1, 2008
    Published: Mar, 2009


    * Corresponding author(s): ndegwa@wsu.edu
 View
 Download
 Alerts
 Permissions

doi:10.2134/jeq2008.0211

Measuring Concentrations of Ammonia in Ambient Air or Exhaust Air Stream using Acid Traps

  1. P. M. Ndegwa *a,
  2. V. K. Vaddellaa,
  3. A. N. Hristovb and
  4. H. S. Jooa
  1. a Biological Systems Engineering, Washington State Univ., P.O. Box 646120, Pullman, WA 99164
    b Dairy and Animal Science Dep., Pennsylvania State Univ., University Park, PA 16802

Abstract

Strong acid solutions have been widely used in acid traps to determine concentrations of ammonia in ambient air or exhaust air stream. A literature survey indicates the method has a long history and a wide variation in use. Through a series of studies, this paper examines several factors including volume of the acid, depth of the acid, and airflow rate; that might affect the efficiency of sulfuric acid traps and recommends steps researchers and other users may take to ensure reliable results from this method. The results from these series of studies indicate: (i) an inverse relationship between the efficiency of the acid traps and the amount of ammonia to be trapped even when the capacity of the acid trap is excessively greater than the maximum theoretical stoichiometric capacity needed to dissolve all of the ammonia, (ii) for the same volume of acid, the efficiency of the acid trap increased with the acid depth but overall, the efficiency at any given acid depth decreased as the amount of ammonia through the trap increased, and (iii) at the two airflow rates examined in this study (0.5 and 1.0 L/min) the efficiency of the acid traps decreased at similar rates as the concentration of ammonia in the sample air increased but the efficiency of the trap was significantly higher at the lower airflow rate. To obtain reliable measurements from this method, therefore, multi-point calibrations within the entire range of target measurements is recommended to provide accurate corrections of the measurements.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2009. American Society of Agronomy, Crop Science Society of America, Soil Science SocietyAmerican Society of Agronomy, Crop Science Society of America, and Soil Science Society of America

Facebook   Twitter