TECHNICAL DOCUMENTATION Chapter II COMPONENTS AND FUNCTIONS

Transcription

1 CONTENT 1 I N T R O D U C T I O N F A N S Combustion air fan Mixing air fan I N I T I A L V E N T I L A T I O N B U R N E R O P E R A T I O N Constant conditions general Constant conditions initial ventilation Fuel operation Constant conditions Oil Burner operation Oil RELEASE coal operation Constant conditions coal Start BKS (brown coal dust) burner Ash removal Start BKS (brown coal dust) burner S T O P B U R N E R Shut-down of the burner oil Shutting down of the burner coal Fault shut-down burner B L O W - O U T O P E R A T I O N Constant conditions blow-out Start automatic blow-out Manual blow-out Shut-down blow-out F U E L / A I R C O M B I N E D C O N T R O L Electronic combined control Control of the fuel - air relation Regulation Control C O N T R O L C I R C U I T S Burner performancee regulator Fuel flow regulation Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 1 of 11

2 8.3 Combustion air regulation Regulation of the mixing air fitting 1 (firing chamber temperature) Adjustment of the mixing air fitting 2 (hot air exit temperature) M A N U A L A D J U S T M E N T O F T H E C O N T R O L E L E M E N T S T H R E S H O L D V A L U E S A N D P A R A M E T E R S O P E R A T I N G P H I L O S O P H Y Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 2 of 11

3 1 INTRODUCTION The following describes the function of a hot gas generator firing system. 2 FANS 2.1 COMBUSTION AIR FAN The combustion air fan is designed for initial ventilation of the system burner operation cooling of the burner equipment The combustion air fan is switched on by the customer control. Independently, starting the firing triggers the command: Requesting combustion air fan from the burner control through the signal exchange to the control system. The running signal must be passed on to the burner control. Furthermore, the fan is also used to provide cooling air to the burner and the flame control systems and must run-on after the burner is switched off, until the temperatures caused by retained heat in the burner chamber and the burner have dropped sufficiently. 2.2 MIXING AIR FAN The mixing air fan is designed for the initial ventilation of the system the burner operation The mixing air fan is switched on by the customer-own control. Independently, starting the firing trig- the signal exchange gers the command: Requesting mixing air fan from the burner control through to the control system. The running signal must be passed on to the burnerr control. The fan is switched off after a certain run-on time. Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 3 of 11

4 3 INITIAL VENTILATION To ensure no combustible mixtures are present in the oven and exhaust gas system, the initial venti- in the firing chamber must lation is started on burner start by the customer s system. For this, the air be exchanged from the fuel system to the chimney entry at least five times. The smoke fuel volume is defined by the customer. Only the amount of combustion air is used to calculate the volume. Initial ventilation is unnecessary if a temperature of at least 750 C is exceeded throughout the firing chamber. 4 BURNER OPERATION The burner can be started depending on the setting Local/Remote, if the following constant conditions are fulfilled and all previous disturbances are acknowledged. 4.1 CONSTANT CONDITIONS GENERAL For burner operation, the following constant conditions are required: EMERGENCY-OFF not operated Burner release by the customer control (e.g. system fan running, free smoke fuel way, etc.) Combustion air fan in operation (switched on by the customer, request after burner is switched on) Combustion air pressure PZAL (request after the end of the start-up time) Combustion air amount FYC Combustion air amount FY Mixing air fan in operation (switched on by the customer, request after burner is switched on) Mixing air pressure PZAL (request after the end of the start-up time) No end position error (burner fittings) Firing chamber pressure PZAH Firing chamber pressure PISALH Firing chamber temperature TISAH Refractory lining temperature cone TSAH Refractory lining temperature cylinder TSAH Hot gas exit temperature TIC Temperature after mill TICSAH (customer side) Flame feedback or after the end of the safety period fuel 4.2 CONSTANT CONDITIONS INITIAL VENTILATION Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 4 of 11

5 Constant conditions general present Combustion air fitting in flush position GZAH Combustion air fitting position GI >90% Combustion air amount FYI , FY > 90% Air staggering fitting in flush position GZAH Air staggering fitting position GI >90% Swirl air fitting in flush position GZAH Swirl air fitting position GI >90% Mixing air fitting 1 in flush position GZAH Mixing air fitting 2 in flush position GZAH No foreign light present 4.3 FUEL OPERATION CONSTANT CONDITIONS OIL General constant conditions are present and the plant has been initially ventilated Oil pressure PZAL Oil pressure PZAH Control air pressure PZAL Nebuliser air pressure PZAL No end position errors (oil fittings) Nozzle retracted (after initial aeration) Ionisation / flame feedback after end of the ignition gas safety time Fuel / air relation within tolerance band after system is operational No runtime error in the starting program Ignition gas pressure PZAL (during ignition) Oil regulator in ignitionn position GZAL (during ignition) Combustion air fitting in ignition position GSAL (during ignition) Control fittings in operational state (after ignition) Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 5 of 11

6 4.3.2 BURNER OPERATION OIL On burner start, the combustion air fan and mixer fan are switched on (if not already in operation) and initial ventilation is started. During this, the combustion air , air staggering , swirl air , mixing air and the mixing air fittings drive into the flushing position. Initial ventilation starts when the end positions GSAH , , , and are reached. After the end of the initial ventilation, the above mentioned combustion air fittings move to the Ignition position, the mixing air fittings to Min position and the nozzle moves in. After reaching the drive posi- tions, the pilot burner is started. To do this, the ignition transformer of the pilot burner is switched on and the ignition gas valves and are opened, so that the fuel air mix formed at the pilot burner is ignited by the high tension ignition spark. Within the ignition gas safety time a stable ignition flame must be formed, confirmed by ionisation feedback or the flame recognition of the optical flame monitors or The ignition transformer is switched off after receipt of the ionisation feedback, the latest, however, after the end of the safety time Ignition gas. At the end of the subsequent stabilisation time, the safety cut-off fittings and and the nebuliser valve are opened and the fuel safety time begins. The main flame must have formed within this time span. After the end of the safety time, the ignition gas valves are closed. After the end of the stabilisation time, the fuel / air ratio is regulated according to the burner perform- ance requirements. 4.4 RELEASE COAL OPERATION The coal release is made up of the following fail-safe designed and processed signals: Safety chain general constant conditions present and o minimum firing chamber temperature (T> C) for pure coal dust operation reached or o start-up fuel in operation (main ignition time lapsed) and o minimum firing chamber temperature (T> C) for mixed operation reached CONSTANT CONDITIONS COAL General constant conditions present Operating conditions coal operation present on customer side Start-up fuel in operation at coal start-up Amount of coal for relation regulation (time-delayed customer side) Amount of coal for control (time-delayed customer side) Fuel / air relation within tolerance band after system is operational Control fittings operational Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 6 of 11

7 Ash disposal flap feedback GSAL or present START BKS (BROWN COAL DUST) BURNER The burner can be started depending on the Local / Remote setting, if the above mentioned constant conditions are fulfilled and all previous disturbances are acknowledged. 4.5 ASH REMOVAL START BKS (BROWN COAL DUST) BURNER Control air pressure PZAL Ash collector feedback end position GSAL present (customer side) Ash removal always takes place automatically in coal operation, if the ash removal setting is set to Automatic. When stationary, the ash removal can, depending on the Remote / Local operating mode, be started from the control system or manually locally. It is always possible to stop ash removal locally and remotely. Automatic operation: In this operating mode, the ash removal is initiated automatically. Manual operation: In this operating mode, the ash removal can be initiated at any time. The flaps are operated at set intervals, with flap opened first. The ash drops into the interme- diate space. Then flap closes and after a certain waiting time flap opens and the ash drops into the dedicated container. When there is a disturbance switched off. in the ash removal cycle, an alarm is triggered but the burner is not 5 STOP BURNER 5.1 SHUT-DOWN OF THE BURNER OIL The burner is shut down if: Stop is selected from the control board (operating level remote) or Stop is operated locally (local operating level) When shutting down the burner, the safety shut-off device is closed instantly and the safety shut-off devices is closed delayed. In automatic operation, the blow-out begins (see Section Blow out operation). The oil regulation fitting is driven to the Min position. 5.2 SHUTTING DOWN OF THE BURNER COAL The burner can only be shut down during coal operation on the customer side. Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 7 of 11

8 5.3 FAULT SHUT-DOWN BURNER The burner is fault shut down if: One of the constant conditions is missing When the burner is shut-down, both safety shut-off devices are closed instantly. There is no blow-out. 6 BLOW-OUT OPERATION The oil pipes are always blown out automatically after the burner is shut down when blow-out is set to Automatic. When stationary, the blow-out can, depending on the Remotee / Local operating mode, be started from the control system or manually locally. It is always possible to stop the blow-out operation locally and remotely. Resetting the start signal for blow-out is only possible locally by unselecting blow-out. The following functions are selectable blow-out operating modes: Unselected: Blow-out is switched off or cannot be switched on. Automatic operation: In this operating mode, blow-out is automatically initiated after operational shut- is off. After the start of the down of the oil firing. Start blow-out: Blow-out can be started manually when the burnerr process, the blow-out times are identical to those in automatic mode. During burner operation, this operating mode cannot be selected. If the blow-out is aborted due to fault shut-down, the blow-out must always be initiated manually once the fault has been corrected. 6.1 CONSTANT CONDITIONS BLOW-OUT Blow-out operation can be initiated automatically, once the following constant conditions are in place: General constant conditions present Ignition gas pressure PZAL constant condition from start of ignition to the end of blow- out. No end position errors (oil fittings) Blow-out not unselected on the operator panel Nozzle retractor in operating position GZAH Before opening the blow-out valve UV at the end of the initial ignition time, the flame feedback message XZAL or XZAL or ionisation feedback message XZAL must be present. If one of those conditions is no longer present during blow-out, blow-out is stopped immediately. 6.2 START AUTOMATIC BLOW-OUT The automatic blow-out is initiated by Stop burner operation (blow-out in automatic mode) Blow-out begins with the operation of the pilot burner. Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 8 of 11

9 The blow-out valve is opened in pulses for a defined period of time. After a given number of pulses, the blow-out valve stays open for a certain time. After the lapse of this time span, blow-out ends. 6.3 MANUAL BLOW-OUT When oil firing is switched off, blow-out can be started manually at any time, provided the general constant conditions for blow-out are in place. Blow-out is then executed as described in automatic mode. Manual blow-out is inoperativee during burner operation with oil. 6.4 SHUT-DOWN BLOW-OUT The blow-out program is cancelled, if: one of the constant conditions is missing or blow-out has locally been unselected or the blow-out time has lapsed. 7 FUEL/AIR COMBINED CONTROL The hot gas generator is equipped with a combined electronic control (fuel - airflow control). The flow- whereby one air and control for air and fuel are designed redundantly according to the regulations, fuel flow control measurement is used for the regulating and the other for the control of the air / fuel amount. 7.1 ELECTRONIC COMBINED CONTROL The electronic combined control calculates the respective fuel and air amounts from the burner perequirements, lambda values, formance requirements. The calculation is based on heating values, air min., max., and ignition performance of the respective fuel. 7.2 CONTROL OF THE FUEL - AIR RELATION The hot gas generator is equipped with two fuel flow meters and two combustion air meters. Regula- tion and control of the fuel - air relation are carried out in 2 separate CPUs. 7.3 REGULATION The main CPU uses curves (traverse lines) to determine the required fuel and combustion air values (incl. lambda) according to the required burner performance. During burner operation, the control de- viation between the required value and current value of the combustion air is controlled. If the deviation is above or below a threshold value L/H, an alarm is triggered after a time de- lay. Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 9 of 11

10 If the control deviation is above or below a threshold value LL/HH, the burner is shut down af- is shut ter a time delay. If the redundant measurement values deviate unacceptably, the burner down. 7.4 CONTROL The 2nd CPU receives the redundant fuel and combustion airflows. Here, the necessary amount of combustion air (including lambda) is calculated using the measured fuel amount and compared with the measured amount of combustion air. During burner operation, the control deviation between the required value and current value of the combustion air is controlled. If the deviation is above or below a threshold value L/H, an alarm is triggered after a time delay. If the control deviation is above or below a threshold value LL/HH, the burner is shut down af- ter a time delay. 8 CONTROL CIRCUITS 8.1 BURNER PERFORMANCE REGULATOR The set value for the burner performance regulator is taken from the output signal of the customer s lead regulator. The output of the burner performance regulator uses the electronic combined control to calculate the set value for the fuel and airflow regulators. The burner regulator can be operated remotely or locally as required. The performance settings are always in % burner performance. 8.2 FUEL FLOW REGULATION The set value for the fuel flow regulator is calculated from the burner performance regulator using the electronic combined control. The calculated set value for the fuel flow is compared to the measured (actual) fuel flow set value. This output value resulting from the control deviation is sent to the fuel flow regulator. The fuel control circuit is in manual operation during burner off time and the starting program, and is switched to automatic operation after the fuel control release. During burner operation, it is not possible to switch to manual operation. This guarantees that a change in fuel flow is not possible without changing the required airflow. 8.3 COMBUSTION AIR REGULATION The set value for the combustion airflow regulator is calculated from the burner performance regulator using the electronic combined control. This set value is multiplied with the lambda curve and then compared to the measured airflow (current value). The lambda curve contains the required airflow value including the excess air. The air control circuit is in manual operation during burner off time and the starting program and is switched to automatic operation after ignition. During burner operation, it is not possible to switch to Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 10 of 11

11 manual operation. This guarantees that the required amount of air for the respective amount of fuel is always present. 8.4 REGULATION OF THE MIXING AIR FITTING 1 (FIRING CHAMBER TEMPERATURE) The mixing air regulation is dependent on the burner performance. The control value of the burner performance regulator is used as traversee set value for the mixing air regulation. The set value is compared with the measured (actual) firing chamber temperature value. This output value resulting from the control deviation is sent to the mixing air regulator. The mixing air control circuit is in manual operation during burner off time and the starting program, and is switched to automatic operation after the fuel control release. During burner operation, it is not possible to switch to manual operation. This guarantees that a change in fuel flow is not possible without changing the required airflow. 8.5 ADJUSTMENT OF THE MIXING AIR FITTING 2 (HOT AIR EXIT TEMPERATURE) The mixing air flap 2 regulates the hot air exit temperature TISAH During initial ventilation the flap is open. During the ignition sequence the flap is in the Min-position. 9 MANUAL ADJUSTMENT OF THE CONTROL ELEMENTS When the burner is switched off, the actuator drives are moved to Min-position. When these positions are reached and the stop steps are followed through, the control commands are deleted. This offers the opportunity to move the actuator drives for servicing or test purposes. 10 THRESHOLD VALUES AND PARAMETERS All the necessary threshold values and parameters are identified and documented during taking into operation. 11 OPERATING PHILOSOPHY FIVES PILLARD DEUTSCHLAND GmbH has the following standard philosophy: The selection of the operating level ( remote or local ) is made from the customer control board. Therefore, operations such as Start, Stop, Confirm are only possible from the selected operating level. Rev.: 0 Created: 24/09/2015 Revision: 03/02/2016 Page 11 of 11