المجلة الدولية للعلوم والتقنية

This research deals with the performance of the developed septic tank Used in the treatment and disposal of wastewater in decentralized areas that do not have a public sewage network, which is disposed of by draining into the soil, leading to soil and groundwater pollution, as is the solution in many cities in Libya, This is done by using a low-cost treatment method and making use of wastewater in irrigation after it has been treated, especially since this water contains nutrients for plants, Where simple modifications were made to the design of the traditional septic tank by building some transverse wall partitions to improve its efficiency. And through laboratory analyzes and periodic follow-up for a period of seven months on a laboratory model using wastewater from the Al-Nahda area in the municipality of Sabratha, the rate of pollutant removal was identified, as the rate of biological oxygen consumption (BOD) reached 69%,chemical oxygen removal rate (COD) 60% and suspended matter removal rate (TSS) 90%, A comparison was also made between this system and the other treatment systems from a technical and economic point of view, in order to reach recommendations about this system. It can be considered a good alternative to the traditional septic tank, as the specifications of the water produced from experimental pilot plant operating with this system in neighboring countries are compatible with the limits of the specifications of the dual-treated water, and by adding Sandy filter, This water will be suitable for agriculture.