Reduction of Anionic Surfactant in Hospital Wastewater

The environmental commitment made by the Hospital Universitario Virgen de las Nieves has recently led to lower water consumption. This decline has caused the side effect of raising the concentration of certain contaminants in the water discharged, by reduction in the amount of solvent. Despite the processes of segregation and treatment of waste, the concentrations of some pollutants in the wastewater exceeded maximum permissible concentrations in local regulations, particularly the so-called anionic tensoactives from the use of cleaning detergents.

The main objective of this paper is to describe the strategy developed for reducing the high concentration of surfactants in hospital wastewater without increasing water consumption or costly investments.

An observational descriptive study was designed to identify the factors causing the high concentration of surfactants. From the simulation of scenarios generated through the deliberate manipulation of the independent variables (concentration of anionic surfactants in detergents, detergent strength, critical areas, shifts, days of week, season), we examine the effect on the dependent variable (concentration of anionic surfactant in the drain networks).

Moreover, the environmental impact, quality of wastewater, has an economic dimension, as it reduces the water treatment tax. The estimated reduction would result in annual savings of 67,047 Euros.

The project, currently underway, has identified operating room areas as the main source of discharge of surfactants in wastewater. Currently we are working on two fronts, the change in the habits of personal cleanliness, and microbiological testing of the effectiveness of alternative detergents with a lower proportion of anionic surfactant.