Bioestimulación de microorganismos como estrategia sustentable de pretratamiento para aguas residuales industriales del procesamiento de aceite de palma: un estudio de caso en Bogotá D.C.

Abstract

Aim of the research was to develop a biocatalyst for biostimulation of the native bacterial population in the grease traps of wastewater from the palm oil physical refining industry, in order to reduce its pollutant load of BOD5, COD, phenols, and fats and oils. The efficiency of biostimulation applied from the environmental dimensions (percentage of removal achieved), economic (treatment costs) and social, from the context of public health through assessing compliance with current legislation was evaluated; from the maximum permissible values in the final efluent. The research methodology is of an experimental kind and was developed in three stages, a first stage of description of the research site, a second stage of information gathering, and a final stage of information analysis to comply with the proposed objectives. Among the main results of the research it was obtained that the biostimulation process was successful and achieved an average removal of 21.5% for BOD, 13.0% for COD, 30.0% for fats and oils, and 29.1% for phenols. Therefore, the balanced addition of the developed biocatalyst and the control of the key factors of biostimulation (Temperature, pH, N, P and BOD) in bacteria native to grease traps in industrial wastewater of palm oil increases the removal of BOD5 and total heterotrophic bacteria, given the correlation of the latter (r-Pearson: 0.737, p-value: 0.005, gl: 12). biostimulation treatment was 123 pesos cheaper for every 100 ppm of BOD5 removed, compared to the conventional treatment carried out; which means that the latter was 46.8% more expensive. From the public health context, biostimulation as a pre-treatment strategy in wastewater is feasible given that the BOD5 parameter (average = 303 mg / l) was always maintained in compliance with the current standard (Colombian standard 631 of 2015) during the six months of the evaluation period. It is concluded that the development of the biocatalyst and the biostimulation process is environmentally acceptable, due to the percentages of removal of the critical pollutants (BOD = 13%, COD = 30%, fats and oils = 29.1%), and economically viable due to having a lower cost-effectiveness ratio compared to conventional treatment (123 pesos cheaper for every 100 ppm of BOD5 to be removed). Finally, from the social dimension of sustainable development in water treatment systems and in the context of public health, biostimulation is considered as a pretreatment strategy in viable wastewater, given that the BOD parameter remained in compliance with regulations, that is responsible for the spread of pathogenic diseases (Osuolale et al., 2015; Verma et al., 2008).