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APPENDIX B 302 4.5.1 Cleaning ashes and slag from the combustion chamber(s) and cleaning of combustion air openings before starting the incinerator (where applicable). 4.5.2 Operating procedures and instructions. These should include proper start-up procedures, normal shutdown procedures, emergency shutdown procedures and procedures for loading garbage (where applicable). 4.6 To avoid the building up of dioxins, the flue gas should be shock- cooled to a maximum 350Â°C right after the incinerator. 5 Operating controls 5.1 The entire unit should be capable of being disconnected from all sources of electricity by means of one disconnect switch located near the incinerator. (See 126.96.36.199) 5.2 There should be an emergency stop switch located outside the compartment, which stops all power to the equipment. The emergency stop switch should also be able to stop all power to the fuel pumps. If the incinerator is equipped with a flue gas fan, the fan should be capable of being restarted independently of the other equipment on the incinerator. 5.3 The control equipment should be so designed that any failure of the following equipment will prevent continued operations and cause the fuel supply to be cut off. 5.3.1 Safety thermostat/draught failure 188.8.131.52 A flue gas temperature controller, with a sensor placed in the flue gas duct, should be provided that will shut down the burner if the flue gas temperature exceeds the temperature set by the manufacturer for the specific design. 184.108.40.206 A combustion temperature controller, with a sensor placed in the combustion chamber, should be provided that will shut down the burner if the combustion chamber temperature exceeds the maximum temperature. 220.127.116.11 A negative pressure switch should be provided to monitor the draught and the negative pressure in the combustion chamber. The purpose of this negative pressure switch is to ensure that there is sufficient draught/ negative pressure in the incinerator during operations. The circuit to the program relay for the burner will be opened and an alarm activated before the negative pressure rises to atmospheric pressure. 5.3.2 Flame failure/fuel oil pressure 18.104.22.168 The incinerator should have a flame safeguard control consisting of a flame sensing element and associated equipment for
APPENDIX B 303 shutdown of the unit in the event of ignition failure and flame failure during the firing cycle. The flame safeguard control should be so designed that the failure of any component will cause a safety shutdown. 22.214.171.124 The flame safeguard control should be capable of closing the fuel valves in not more than 4 s after a flame failure. 126.96.36.199 The flame safeguard control should provide a trial-for-ignition period of not more that 10 s during which fuel may be supplied to establish flame. If flame is not established within 10 s, the fuel supply to the burners should be immediately shut off automatically. 188.8.131.52 Whenever the flame safeguard control has operated because of failure of ignition, flame failure or failure of any component, only one automatic restart may be provided. If this is not successful then manual reset of the flame safeguard control should be required for restart. 184.108.40.206 Flame safeguard controls of the thermostatic type, such as stack switches and pyrostats operated by means of an open bimetallic helix, are prohibited. 220.127.116.11 If fuel oil Pressure drops below that set by the manufacturer, a failure and lockout of the program relay should result. This also applies to sludge oil used as a fuel. (Applies where pressure is important for the combustion process or a pump is not an integral part of the burner.) 5.3.3 Loss of power If there is a loss of power to the incinerator control/alarm panel (not remote alarm panel), the system should shut down. 5.4 Fuel supply Two fuel control solenoid valves should be provided in series in the fuel supply line to each burner. On multiple burner units, a valve on the main fuel supply line and a valve at each burner will satisfy this requirement. The valves should be connected electrically in parallel so that both operate simultaneously. 5.5 Alarms 5.5.1 An outlet for an audible alarm should be provided for connection to a local alarm system or a central alarm system. When a failure occurs, a visible indicator should show what caused the failure. (The indicator may cover more than one fault condition.) 5.5.2 The visible indicators should be designed so that, where failure is a safety-related shutdown, manual reset is required. 5.6 After shutdown of the oil burner, provision should be made for the fire box to cool sufficiently. (As an example of how this may be accomplished, the exhaust fan or ejector could be designed to continue