AMMONIA DIFFUSION AND CAPTURE INTO A TUBULAR GAS-PERMEABLE MEMBRANE USING DILUTED ACIDS

作者：Majd A M Samani^*; Mukhtar S

来源：Transactions of the ASABE, 2013, 56(5): 1943-1950.

• Ammonia diffusion
• Diluted acid
• Gas-permeable membrane
• Mass flux
• Mass transfer coefficient
• Recipient solution

Tubular gas-permeable membranes (GPM) provide an alternative method for ammonia (NH3) mitigation from liquid dairy manure (LM). A setup consisting of a closed LM chamber, two sulfuric acid (H2SO4) solution flasks, and two GPM systems was utilized in four experiments in order to evaluate the use of diluted acids for capturing NH3 diffused from LM into the membrane. The H2SO4 solutions (recipient solutions) were circulated in the GPM systems with nominal pH values of 2, 3, 4, and 5. The initial pH values of the recipient solutions rose quickly as NH3 was captured by them and then stabilized between 7 and the pH value of the corresponding LM treated with the GPM systems. The pH 2 solution captured the greatest concentration of NH3 among all experiments. However, the NH3 mass fluxes and mass transfer coefficients did not change significantly as long as the recipient solution pH values remained below 7. In all experiments, NH3 fluxes remained positive, showing that NH3(g) diffused into the membrane not only because of the concentration gradient across the membrane but also due to gas uptake that occurred from solution circulation in the GPM tubes.

• 出版日期2013-10