Resource added for the Environmental Engineering Waste and Water Technology program 105062.

The potential for sulfate retention is an important soil feature for buffering of atmospheric acid deposition. We studied the effects of increasing additions of different neutral salts and acids on mobilization and retention of SO₄ ²- in acid forest soils. Soils containing up to 11 mmol SO₄ ²- kg⁻¹ were equilibrated with H₂O, NaCl, MgCl₂, and HCl. Release of SO₄ ²- was highest with H₂O and NaCl additions and lowest when HCl was used. Increasing the ionic strength of the added solutions caused decreasing SO₄ ²- concentrations in equilibrium solution. Decreasing pH in equilibrium solution was found to be the reason for the decrease in release. Even when the pH was < 4, the SO₄ ²- release decreased. We assume that this finding resulted from the fact that in the soils studied the SO₄ ²- sorption was controlled by the high contents of Fe oxides/hydroxides.Experiments with Na₂SO₄, MgSO₄, and H₂SO₄ demonstrated that the B horizons already containing high amounts of SO₄ ²- were still able to retain SO₄ ²-. Sulfate retention increased in the order Na₂SO₄ < MgSO₄ < H₂SO₄, which corresponds to increasing H⁺ availability. The higher SO₄ ²- retention along with MgSO₄ compared to Na₂SO₄ may be caused by higher potential of Mg to mobilize soil acidity compared to Na.

Stack gases of wood and oil burning boilers were analyzed by a low resolution FT-IR gas analyzer. Concentrations of carbon dioxide (CO₂), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO₂), nitrous oxide (N₂O), hydrogen cyanide (HCN), sulfur dioxide (SO₂), methane (CH₄), and water vapor (H₂O) were predicted in real time by multicomponent analysis. Detection limits, linearity, analysis accuracy and long time repeatability were experimentally determined for selected gas components. Applicability of the measurement method was demonstrated by analysis of stack gas mixtures of known concentrations. The results indicate that all the primary stack gas components can be measured by the low resolution FT-IR gas analyzer with comparable results to single component measurement methods.