抄録
This report is related to the septic tank which a Bacillus bacteria and a iron bacteria were used for. The iron bacteria is made to propagate by conducting the thermal insulation to home scale septic tank and putting iron scraps into the anaerobic region, further water purification is carried out. COD[ppm] is used for the index of the water quality processing effect, and the desired value is made to be 10[ppm] or less. The conclusion were as follows : 1) The COD value of the first septic tank in putting the garbage is 2000∿5000[ppm]. In addition, COD of the second tank exit was kept to 20[ppm] or less in the case. 2) It is based that COD decreases with the temperature rise on the work of fungus which makes the walnut charcoal to be house and iron bacteria.