Submitted to: Transactions of the ASAE
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/10/2000
Publication Date: 6/20/2001
Citation: ALLRED, B.J., BROWN, G., BRANDVOLD, L. ENHANCED ANIMAL WASTE MANAGEMENT THROUGH APPLICATION OF SURFACTANTS TO SOILMATERIAL: LABORATORY FEASIBILITY TESTING. TRANSACTIONS OF THE AMERICAN SOCIETY OF AGRICULTURAL ENGINEERS. 2001. V. 44. P.513-524. Interpretive Summary: Laboratory experiments were conducted to determine the feasibility of using surfactants to enhance feedlot and dairy facility soil performance with regard to animal waste management considerations. To be effectively used as a soil amendment, a surfactant must satisfy two criteria. Limiting the movement of animal waste leachate through soil is one, while the other is the ability to maintain acceptable engineering soil compaction characteristics. Three surfactants were tested on a sandy loam soil. Of the three evaluated, a cationic surfactant, polyoxypropylene methyl diethyl ammonium chloride, performed best as a soil additive. It reduced water movement through soil under saturated and unsaturated conditions and showed no adverse impact on soil mechanical compaction. Results from this study indicate the feasibility of surfactants to enhance animal waste management soil performance, however, more work needs to be done. In particular, a wide variety of surfactants should be tested on a number of different soils.
Technical Abstract: Laboratory testing was conducted to determine the feasibility of using surfactants to enhance soil performance with regard to animal waste management at feedlot and dairy sites. The best surfactants are those that substantially lessen the amount leaching as determined by reductions in saturated hydraulic conductivity, soil moisture diffusivity and unsaturated soil wetting front penetration. In addition, the ability for surfactant treated soils to maintain acceptable mechanical compaction characteristics was evaluated. Saturated hydraulic conductivity was measured using falling-head permeability tests. Transient unsaturated horizontal column experiments provided information concerning surfactant influence on soil moisture diffusivity and wetting front penetration. Standard Proctor methods were applied in the study of surfactant impacts on mechanical compaction. Three surfactants, one anionic and two cationic, were tested on a sandy loam. The anionic surfactant, sodium dodecyl benzene sulfonate and one of the two cationic surfactants, polyoxypropylene methyl diethyl ammonium chloride, produced considerable reductions in saturated hydraulic conductivity, soil moisture diffusivity and unsaturated soil wetting front penetration. With regard to mechanical compaction, the anionic surfactant and the other cationic surfactant, tetradecyl trimethyl ammonium bromide, affected decreases in the optimum moisture content along with the moisture content range corresponding to 90% or 95% maximum dry bulk density. Overall, the test results support the feasibility of using surfactants to enhance soil performance for animal waste management.