Combined coagulation flocculation pre treatment unit for municipal wastewater

The potentials of using the hydraulic technique in combined unit for municipal wastewater treatment were studied. A combined unit in which processes of coagulation, flocculation and sedimentation, has been designed utilizing hydraulic mixing instead of mechanical mixing. Ajar test treatability study has been conducted to locate the optimum dose of the coagulants to be used. Alum, ferrous sulfate, ferric sulfate, a mixture of ferric and ferrous sulfates, and mixture of lime and ferrous sulfate were all tested. A pilot unit was constructed in the existing wastewater treatment plant at El Mansoura governorate located in north Egypt. The optimum dose of coagulants used in the combined unit gives removal efficiencies for COD, BOD, and total phosphorous as 65%, 55%, and 83%, respectively

Mutagenic effect of rift valley fever virus as measured by indication of chromosomal aberrations and formation of micronuclei in mice bone marrow cells

The mutagenic effect of Rift Valley fever [RVF] virus was tested in male mice bone marrow cells. Three virus titers were chosen [low [L], intermediate [IM] and high [H]]. These were 3, 300 and 3000 VP/dose, respectively. Mice were inoculated with each titer and samples were taken 24 and 48 hours later from bone marrow. An increase in chromosomal aberrations [structural and numerical] was observed in some treatments with RVF virus. The significant structural chromosomal aberrations are in the form of gape and centromeric attenuations, while the numerical aberration was endomitosis. All treatments showed a decrease in mitotic index [number of dividing nuclei per 300 cells], this decrease was highly significant. Although, the number of micronucleated PCE increased after inoculation with all treatments, the increase was below the significant level. Since there is no information available on the mutagenicity of RVF virus, more cytogenetic studies are suggested, the result of which could be compared with these results. This may throw some light on the mutagenic effect that could be produced by RVF virus