Author(s)

H. T. El-Zanfaly, A. Mostafa, M. Mostafa & I. Fahim

Abstract

A mixture of five selected, adapted, enzyme active producer bacterial species has been used as an additive to septic tanks in order to test its ability to increase treatment efficiency. Regarding the septic tanks receiving waste with medium load, the maximum removal was achieved at day thirty and showed ranges for removal % reaching 91.3–94.4, 93–95.8, 90–91.7, 75–87, and 99.95–99.99 for COD, BOD5, TSS, oil and grease and total coliforms, respectively. Septic tanks without bacterial additives were able to show removal % ranged as 79.3–88.5, 80–85.5, 75.1–83, 28–41.7 and 98.5–99.85 for the same parameters. Septic tanks that receiving influent with high load of pollutants, the maximum removal was achieved during the period of day 36–42 after addition of bacteria. The removal percentages for COD, BOD5, TSS, oil and grease and total coliform were ranged as 93.8–97.2, 94.5–97.0, 94.0–97.9; 64.0–93.8; 99.81–99.99, respectively. Septic tanks without bacterial additives showed percentages of removal ranged as: 64.7–87.2, 73.4– 89.6, 56.7–86.9, 34.6–45, and 92.8–99.28 for COD, BOD5, TSS, oil and grease and total coliforms, respectively. Keywords: wastewater treatment, Egyptian rural area, septic tanks, bacterial additives. 1 Introduction Septic tanks/soil absorption systems are an option to consider wherever a centralized treatment system is not available. It has been the most popular on-site

Keywords

wastewater treatment, Egyptian rural area, septic tanks, bacterial additives