Chemical and hazard analysis of sludge of the wastewater treatment system in the industry of palma

Abstract

The present study analyzed the chemical and biological components of the sludge generated in the industrial wastewater treatment system in a crude palm oil extractor, determining the dangerousness and identifying the final destination thereof, in two zones, the oxidation lagoon No. 4 and in the geotube. In addition, it was established if the flocculant used in the passage of mud from the lagoon to the geotube affects its chemical characteristics. For this, three samples were taken in three different days and months. For oxidation lagoon No. 4, three subsamples were collected at different points to form a composite sample, and in the geotube samples were taken at 0.5 and 2 m depth. Analyzing agricultural parameters such as NPK, high levels of nitrogen and phosphorus concentration were obtained, compared with fertilization guidelines, and adequate levels for potassium, which indicates that it can be used for agricultural use, the resulting NPK ratio is 3: 3 :1. The corrosivity based on the pH of the mud is within the "non-corrosive" range according to the regulations. The reactivity, based on the level of cyanides, was established as negligible. Heavy metal toxicity, in terms of nickel, chromium, lead and cadmium, was below permissible levels. The flammability of sludge, qualitatively, was determined to not register the presence of flammable gases. In the biological parameter infectious by concentration of total coliforms, the result is under the permissible limits. Finally, the mud of both the lagoon and the geotube turns out to be "non-hazardous" according to national and international regulations and its chemical characteristics are not altered by the use of the indicated flocculant.