RESUMEN
It is important to protect the soil and groundwater from the pollution originating from leachate. Compacted clay soils is a favorable and economic method to protect groundwater and soil against contamination. In this study, compaction tests of leachate was done by using Modified Proctor method. The effects of microbial activity on the permeability of compacted clay soils were analyzed and the obtained data were applied to k-Nearest Neighbors (k-NN) method to predict the permeability of soils in landfill sites. k-NN method, which is a non-parametric distance-based machine learning method and widely used in classification and regression problems was applied to model the relationship between the microorganisms and the permeability. By using k-NN classification method, total heterotrophic bacteria and fungi microorganisms correctly classified the permeability variance as 78.59% and 77.31% success rate, respectively. Also, k-NN modelling was set on regression mode to predict permeability value and produced similar success rates in regression similarity with the actual value. Although, fecal coliforms and fecal streptococci microorganisms had neutral or negative contribution on analyses. For prediction accuracy and regression analysis, the k-NN method was considered for modeling the data. The results of the k-Nearest Neighbors method proved that it is a promising tool for predicting permeability of compacted clay by using microbial activity.
Asunto(s)
Arcilla , Contaminantes Químicos del Agua , Permeabilidad , Eliminación de Residuos , SueloRESUMEN
This study was focused on determining the optimal operational conditions of a small domestic wastewater treatment plant (SWP) with a flow rate of 1000 m3 d(-1) using oxygen uptake rate (OUR) data, microscopic analyses, and effluent toxicity testing with Daphnia magna in parallel to wastewater characterization. Chemical analyses of nine samples, taken from different points of the treatment plant over a nine months period, presented strong domestic wastewater characteristics. The plant performance for meeting discharge standards was not sufficient enough for TP parameter. Aeration capacity and sludge recycle ratio were adjusted to improve the performance of the system and to prevent any operational problems, such as bulking. Although the inflow was 100% toxic, effluent toxicity following treatment was decreased to 5%. Filamentous bacteria were in "excessive" amount. The dominant filamentous bacteria species were determined as Nostocoioda limicola II. Reevaluation of the discharge limits with respect to nutrient removal, geographic location, and receiving water quality subject to treatment effluent discharges.
Asunto(s)
Oxígeno/metabolismo , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/aislamiento & purificación , Contaminantes del Agua/toxicidad , Purificación del Agua/métodos , Animales , Bacterias , Daphnia , Dinámica Poblacional , Control de Calidad , Movimientos del AguaRESUMEN
Corn wet mill effluents are studied in terms of their characteristics relevant for biological treatment. They have a high COD of mainly soluble and biodegradable nature, with practically no soluble inert components. They generate a relatively high level of soluble residual metabolic products, which affects the choice of the appropriate biological treatment and favors aerobic activated sludge process. Experimental assessment of process kinetics yields typical values. Hydrolysis of the slowly biodegradable COD, the rate limiting step for the utilization of substrate, is characterized by an overall rate coefficient, which is within the range commonly associated for the hydrolysis of starch.