P8.2.1.4 Use bench-scale and Manganese. Manganese Carry out pilot-scale tests to concentration is manual KMnO4/air determine the best more than 50% checks on dose set-point KMnO4 dose or of the MAV. manganese incorrect/ aeration rate. removal and dose No sign of adjust oxidant calculation Use a dose controller insoluble dose incorrect. (eg, manganese accordingly. controller) formation that will take account directly after Start of changes in water oxidation calculation chemistry, or monitor (metals must be checks. the manganese insoluble to be concentration often removed). enough so that changes in water chemistry can be matched. From time to time have a second person check the dose calculations. P8.2.1.5 Regular manual Manganese. Manganese Recalibrate checks on controller concentration is controller. Dosing calibration. more than 50% controller Increase of the MAV. incorrectly oxidant dose calibrated. No sign of rate until insoluble recalibration manganese can be formation undertaken. directly oxidation (metals must be insoluble to be removed). Calibration schedule not signed off. P8.2.1.6 Install an alarm to Manganese. Manganese Install alarm warn when the concentration is system. KMnO4/air Maintenance KMnO4 supply is more than 50% supply log. Urgently order running low. of the MAV. exhausted. replacement Ensure a reserve No sign of chemicals. supply of KMnO4 is insoluble Start log of kept on site. manganese oxidant use. formation Keep records of Initiate pump directly oxidant use to provide maintenance oxidation a guide to the length programme. (metals must be of time the chemical insoluble to be supply is likely to last. removed). Schedule a preventive maintenance programme for air pumps. Event: NOT ALL THE MANGANESE REMOVED cont’d
P8.2.1.4 KMnO4/air dose set-point incorrect/ dose calculation incorrect. Use bench-scale and pilot-scale tests to determine the best KMnO4 dose or aeration rate. Use a dose controller (eg, controller) that will take account of changes in water chemistry, or monitor the manganese concentration often enough so that changes in water chemistry can be matched. From time to time have a second person check the dose calculations. Manganese. Manganese concentration is more than 50% of the MAV. No sign of insoluble manganese formation directly after oxidation (metals must be insoluble to be removed). Carry out manual checks on manganese removal and adjust oxidant dose accordingly. Start calculation checks. P8.2.1.5 Dosing controller incorrectly calibrated. Regular manual checks on controller calibration. Manganese. Manganese concentration is more than 50% of the MAV. No sign of insoluble manganese formation directly oxidation (metals must be insoluble to be removed). Calibration schedule not signed off. Recalibrate controller. Increase oxidant dose rate until recalibration can be undertaken. P8.2.1.6 KMnO4/air supply exhausted. Install an alarm to warn when the KMnO4 supply is running low. Ensure a reserve supply of KMnO4 is kept on site. Keep records of oxidant use to provide a guide to the length of time the chemical supply is likely to last. Schedule a preventive maintenance programme for air pumps. Manganese. Maintenance log. Manganese concentration is more than 50% of the MAV. No sign of insoluble manganese formation directly oxidation (metals must be insoluble to be removed). Install alarm system. Urgently order replacement chemicals. Start log of oxidant use. Initiate pump maintenance programme. Event: NOT ALL THE MANGANESE REMOVED cont’d
treatment-iron-manganese-removal-feb14-v2.docx