This paper deals with the calibration of the model for the utilization rate of organic and nitrogenated substrates (URONS) by the microorganisms in a sequencing batch reactor. The URONS model parameterization was carried out using data obtained from two experimental designs (EDs) applied on tannery wastewater (TW), which included as factors: First ED (aeration sequence and cycle duration) reached a COD removal efficiency (RE) between 29% (cycle duration of 6 h) and 48% (cycle duration of 24 h).Second ED (aeration sequence and filling time) obtained COD-RE (47-51%), NH 4 -N-RE (71-91%), and TKN-RE (50-67%). The URONS model was based on Monod's equation modification. For the first ED, the results of the maximum URONS parameter (r sm ) of 135-946 mg/L⋅h suggest the organic substrate accumulation due to a possible inhibition of the microorganisms by TW substances such as heavy metals and metal halides. For the second ED, the r sm parameter values resulted negative and varying in the order of −10 −2 to −10 −4 mg/L⋅h with respect to (r sm ) for the first ED indicating that a better microorganism performance for URONS occurred in the second ED. For both EDs, the saturation parameter (K s ) values compared to the effluent substrate concentration suggest that the primary substrate for biodegradation was present in the TW.

This paper deals about an approach to remediation for treating soils and groundwater contaminated with hydrocarbons in a tropical aquifer caused because of leaks from underground tanks in a gas station of Venezuela. Ex situ and in situ remediation treatment options were designed, recommending the ex situ remediation due to microbial inhibition produced by the presence of heavy metals and multiple strata with different soil materials in the interface between the unsaturated and saturated zones, where the most significant hydrocarbon concentrations were found. Under these conditions, ex situ bioremediation option based on two coupled bioreactors can overcome environmental limiting factors by optimizing temperature, oxygen supply, nutrient status, contaminant bioavailability, and microbial population. Ex situ remediation included for soil treatment, a Soil‐Slurry Sequencing Batch Reactor (SS‐SBR) and Upflow Anaerobic Filter separated in three phases (UAF‐3SS). For groundwater treatment SBR‐UAF‐3SS sequence was established. The first phase was represented by SS‐SBR for ex situ bioremediation of soils, configuring COD removal efficiency of 80%. It was set that SS‐SBR performs functions for groundwater treatment operating as SBR, removing 60% COD. For the second phase, an upflow anaerobic filter separate in three phases (UAF‐3SS) designed to ensure 99% COD removal efficiency.

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Los residuos sólidos han experimentado un aumento desproporcionado respecto a su generación debido al crecimiento poblacional y a los malos hábitos de consumo por parte de las personas quienes adquieren productos en algunos casos sin necesitarlos y que después de ser utilizados los descartan como un desecho, bien sea el producto en desuso o los diferentes empaques que estos poseen, generando cantidades excesivas de residuos que de no ser bien manejados y tratados de forma adecuada pueden ser una fuente de contaminación. La gestión de estos residuos se ha convertido en un verdadero desafío para los entes gubernamentales, ya que no se cuenta con políticas diseñadas para abordar de forma integral la eliminación de los residuos, sin embargo, existen instituciones y empresas, así como asociaciones civiles y cooperativas que se encuentran trabajando en la recuperación y el aprovechamiento de los mismos. El objetivo de esta obra es dar a conocer los diferentes tratamientos que pueden ser aplicados a los residuos sólidos para su recuperación y aprovechamiento, mediante la recopilación de información y estudios de casos, que permitieron exponer los métodos y tecnologías más apropiados para la gestión de estos residuos, destacando la aplicación de tratamientos biológicos por su bajo costo, disminución de residuos domiciliarios, menor requerimiento de espacio y maquinarias, además de su aprovechamiento energético.