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Detection and characterization of hidden industrial inflows causing high fluctuations of the inlet load, is a challenging issue pushing plant operators for a cost-effective solution at regional wastewater treatment plants (WWTPs). On the other hand, carbon source of food industrial origin may have a good use at WWTPs facing otherwise inlet carbon source deficiency. In a case study of a regional domestic WWTP receiving seasonally organic carbon-rich discharge from a fruit juice factory, a new method combining on-site measurements and mathematical modelling was developed and successfully applied for estimating the quality and quantity of both industrial influent load and incoming domestic wastewater streams properly. The originally un-staged bioreactor system operated at low dissolved oxygen (low DO) concentration was unable to meet effluent nitrogen requirements with an additional constant risk of encouraging filament growth. A novel screening method based on special sampling campaigns for estimating carbon availability and C:N ratios of influent wastewater streams coming separately from the large catchment area, was developed and applied. Staging of the previously low DO basins into a flexible system containing non-aerated selectors proved to be efficient for enhancing both biological nitrogen removal and sculpturing appropriately settling biomass. [ABSTRACT FROM AUTHOR]

In this study, seismic performance of the existing M0 Háros Highway Bridge in Hungary is evaluated. The large-span bridge is designed with minimal consideration of seismic actions, seismic resistance of certain piers, bearings and pile foundations is not adequate. Eight different demand mitigation methods are evaluated considering quasi-elastic configurations as well as non-linear systems adopted with non-linear anti-seismic devices (NLASD). To accelerate the preliminary design phase, an equivalent linear analysis (ELA) methodology is worked out. Keeping in mind the limitations of the ELA method, non-linear time-history analysis (NLTHA) is also applied for the retrofitted configuration for validation purposes. Comparison of the two methods shows that the ELA method gives the designer adequate, still conservative results for optimal retrofit decisions. [ABSTRACT FROM AUTHOR]