Figure 1. Typical sewage treatment works schematic flow diagram in Hong Kong Hong Kong has the geographical advantage of being situated on the coast and therefore it is possible to use dual water supply systems (fresh + sea water systems in two separate distribution networks) for potable and non-potable uses. From the sea water supply system, about three quarters of the population in Hong Kong ...

Most of industrial processes are nonlinear, not stationary, and dynamical with at least few different time scales in their internal dynamics and hardly measured states. A biological wastewater treatment plant falls into this category. The paper considers modelling such processes for monitorning and control purposes by using State Space Wavelet Neural Networks (SSWN). The modelling method is ill...

Sydney Water Corporation has deployed on-line instruments in a three year study of trade waste sites in wastewater networks. The purpose of this study was to ascertain whether target substances could be isolated from the background chemical matrix via online measurements, including online UV-Vis spectroscopy. Several substances were identified and calibrations developed from the spectral data t...

Cascade process, such as wastewater treatment plant, includes many nonlinear sub-systems and many variables. When the number of sub-systems is big, the input-output relation in the first block and the last block cannot represent the whole process. In this paper we use two techniques to overcome the above problem. Firstly we propose a new neural model: hierarchical neural networks to identify th...

ublicly owned treatment works (POTWs) are beginning the process of identifying air emissions from their wastewater treatment and collection facilities. Many of these facilities will be required by local and state regulatory agencies to reduce emissions to meet air quality or health risks standards. Emissions include odors and toxic, reactive, volatile and criteria pollutants. A wide range of re...

An analytical method based on on-line SPE-LC-APCI-MS/MS has been developed for the detection and quantification of eight selected estrogenic and progestagenic steroid hormones; estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), levonorgestrel (LEVO), medroxyprogesterone (MEDRO), norethindrone (NORE) and progesterone (PROG) in wastewater matrices. The injection volume co...

Erratum: “Radionuclides in Fracking Wastewater: Managing a Toxic Blend” The Focus article “Radionuclides in Fracking Wastewater: Managing a Toxic Blend” [Environ Health Perspect 122:A50–A55 (2014); http://dx.doi.org/10.1289/ehp.122-A50] incorrectly stated that Pennsylvania requires pit liners for temporary impoundments and disposal to have a minimum thickness of 30 mm. The correct minimum thick...

On-site wastewater treatment systems (OWS) are a common means of wastewater treatment in coastal North Carolina, where the soils are sandy and groundwater is relatively close to the surface (<5 m). Wastewater contains elevated concentrations of pathogenic microorganisms that can contaminate groundwater and surface water if OWS are not operating efficiently and distributing wastewater equally to...

The efficiency of the Wastewater Treatment Plant (WWTP) strongly depends on the inlet flow and the component concentrations of the wastewater. The forecasting of WWTP load gives promising opportunities to accomplish relevant operational actions. A predictive control strategy has been implemented. Taking advantage of the recognized properties of universal approximation of neural networks (NN), a...