Evaluation of genetic models for COD and TSS estimation in wastewater through its spectrophotometric response.

In an urban wastewater treatment plant (WWTP), early knowledge of the pollutant load levels throughout the plant is key to optimize its processes and achieve better purification levels. Molecular spectrophotometry has begun to gain prominence in this wastewater characterization process, as it is a simple, fast, inexpensive and non-invasive technique. In this research work, different mathematical models based on genetic algorithms have been developed for the estimation of chemical oxygen demand (COD) and total suspended solids (TSS) from the spectral response of the samples, measured in the 380-700 nm range by means of a light-emitting diode (LED) spectrophotometer developed by the researchers. A field campaign was carried out in Mapocho-Trebal WWTP (Chile), where 550 samples were obtained in three different parts of the plant: at the inlet (raw wastewater), at the outlet (secondary treated wastewater) and at the outlet of the primary clarifier. A total of 18 estimation models have been calculated by mean of HeuristicLab software, which have presented a high accuracy, with a Pearson's coefficient between 80 and 90% in most cases. In order to achieve the most accurate models possible to characterize each part of the plant, specific models have also been developed, as well as combined models that are valid for all types of wastewater.

Design and Implementation of a Mixed IoT LPWAN Network Architecture.

IoT is much more than a large number of objects or customer devices connected to the Internet. IoT offers organizations many more opportunities than they can imagine. According to this, sooner or later they will probably choose to build their own IoT network. In this article, we review the technologies of IoT LPWAN Sigfox and LoRa. It can be considered the most important at present due to its ability to make the smart city possible. We also propose the development, deployment and implementation of a mixed IoT architecture LoRa-Sigfox composed of components based on open hardware and software. The architecture is evaluated in a real environment focused on remote monitoring of water meter devices.