IMPLEMENTATION OF CLOSED-LOOP WATER RECYCLING SYSTEM AND PURIFICATION OF WASTEWATER FROM PETROLEUM PRODUCTS IN WAGON WASHING ENTERPRISES

Abstract

In the context of global climate change and increasing water scarcity, greening industrial sectors, particularly the railway transport infrastructure, has become  an urgent necessity. Wagon cleaning and washing depots consume enormous amounts  of fresh water and generate highly toxic wastewater containing high concentrations of  petroleum products, lubricants, heavy mechanical impurities, and synthetic surfactants. 
Discharging this effluent into general sewage networks or open water bodies causes  irreversible damage to soil structures and groundwater ecosystems. This paper presents  a comprehensive scientific and technical solution for the implementation of a closed loop water recycling system (AquaLoop) in wagon cleaning depots. The methodology  integrates a multi-stage treatment process including primary hydrodynamic sedimentation, coaxial separation for oil-water coalescent skimming, and dissolved air  flotation (DAF) to effectively remove micro-particles and surfactants. Experimental data  indicates that this multi-barrier filtration configuration achieves up to 98.5% purification  efficiency of complex petroleum fractions. The proposed closed hydraulic model allows 
for at least a 90% reduction in fresh water consumption by recycling the treated technical  water back into the washing line. The practical application of this engineering approach  eliminates industrial wastewater discharge, ensures resource-saving operations in the  wagon sector, and aligns railway logistics with international ecological sustainability  standards.