No abstract

The treatment of domestic wastewater by sand filters is a very interesting alternative technique to collective sewerage in rural areas. In order to assess the accuracy of this technique in Algeria, a feasibility study based on a statistical survey and an experimental study is carried out. The aim of the statistical survey is to determine the potential for the application of this technique by evaluating the rate of connection to collective sewerage networks and the existence of a sewage treatment system in rural areas. The purpose of the experimental study is to assess the suitability of the local sands for this type of process. In this paper the treatment performance over time of two different sands (medium and coarse) are evaluated. The chemical analyses of wastewater and filtered water showed a removal ranges between 57% and 74% for medium sand and between 7% and 49% for coarse sand.

Forecasting and monitoring the parameters of a drinking water network such as flow, pressure and quality are essential issues for the operator in order to guarantee a compliant distribution at all times. Water leaks are the main problem in the management of drinking water networks, so a drinking water network must be reliable and sustainable to meet the needs of subscribers. The modeling of a network allows, among other things, to determine distribution strategies in order to guarantee continuous quality of service. The EPANET modeling software, developed by the US Environmental Protection Agency, enables the hydraulic and quality behavior of a water distribution network to be simulated on the basis of its parameters. Our work consists of simulating an existing network in the new city of Guelma in order to check all the necessary elements of the network, namely pressure, speed, flow and water quality. The results obtained verified that the pressure at all junctions and the flow rates with their velocities at all mains is sufficiently feasible to supply adequate water to the network in the study area. These results will help to better understand the pipeline network in the Study Area and allow the Study Area to be studied in the future.

The aim of the current paper is to revisit the performance of spectral clustering algorithms for water distribution networks. In the literature, there have been attempts to introduce improved algorithms based on graph theory. We focus on a class of these algorithms that applies the concepts of the spectral clustering approach. We assess the performance of spectral clustering algorithms on a wider range of water network types (i.e. large, medium, and small sized networks) using a wider range of clustering methods (both partitioning and hierarchical) and performance indicators. Our findings suggest that partitioning methods, such as k-means are not consistently efficient in all types of networks. Nonetheless, the Partitioning Around Medoids (PAM) algorithm shows a relatively good performance according to modularity, while the internal indices of k-means and hierarchical clustering algorithms are more efficient. Stability indices show that PAM and CLARA algorithms are more efficient.