PALL CORPORATION MICROFILTRATION SYSTEM SYSTEM FUNCTIONAL DESCRIPTION MARCO I SLAND (FL) WTP Pall SAP Number: 01.00172 Pall DIR Number: 10000027705 Document Revision Level: Document Issue Date: 00 Dec-2-2010 MarcoIsland FL SFD Rev 00.doc
IMPORTANT READ THIS FIRST Before attempting to operate or install this equipment, Pall Corporation requires all operators to read and understand this Operation and Maintenance manual. Attempting to operate any Pall Corporation equipment without first reading the Operation and Maintenance manual may result in personal injury and/or product damage and may void any and/or all warranties. Direct all questions and/or inquiries to Pall Technology Services: Telephone: 1-866-475-0115* or 1-607-753-6041 Fax: 1-607-753-8525 Email: pall_technology_csc@pall.com * The above telephone number (1-866-475-0115) is toll free from 9 A.M. 4 P.M. U.S. Eastern Time. After 4 P.M., a service charge applies unless the customer has an existing Pall service contract. Throughout this manual: - The word customer refers to Marco Island (FL) WTP. PALL MEMBRANE MICROFILTRATION SYSTEM
T ABLE OF C ONTENTS REVISIONS 6 TABLE A PALL CORPORATION REVISION HISTORY 6 1 MICROFILTRATION SYSTEM OPERATION 7 1.1 INTRODUCTION 7 1.2 THE MICROFILTRATION (MF) SYSTEM PROCESSES 9 1.3 PROGRAMMABLE LOGIC CONTROLLER (PLC) MODES 9 1.3.1 DEFINITION 9 1.3.2 GROUPING 10 1.3.3 MODES 10 1.3.3.1 AUTO 10 1.3.3.2 MANUAL 10 1.3.3.3 DISABLE 11 1.3.4 MODE SELECTION 11 1.4 FILTER RACK UNIT 12 1.4.1 FILTER RACK AUTOMATIC MODE OPERATION 12 1.4.1.1 FILL SEQUENCE 12 1.4.1.1.1 INITIAL STARTUP 13 1.4.1.1.2 FILL CYCLE 13 1.4.1.2 FORWARD FLOW 14 1.4.1.3 FLUX MAINTENANCE 14 1.4.1.3.1 AIR SCRUB (AS) 15 1.4.1.3.2 FLUSH (FL) CYCLE 16 1.4.1.3.3 REVERSE FILTRATION (RF) CYCLE 16 1.4.1.4 INTEGRITY TEST (IT) 18 1.4.1.5 ARBITRATION 20 1.4.1.6 INDIVIDUAL FILTER RACK SHUTDOWN 21 1.4.2 ENHANCED FLUX MAINTENANCE (EFM) AND CLEAN-IN-PLACE (CIP) 22 1.4.2.1 ENHANCED FLUX MAINTENANCE (EFM) 23 1.4.2.1.1 CLEAN-IN-PLACE (CIP) 25 PALL MICROFILTRATION SYSTEM 3
1.4.2.1.1.1 EFM AND CIP RECIPE STEPS 25 1.4.2.1.1.2 RECIPE STEP PUMPED DRAIN TO CHEMICAL DRAIN 26 1.4.2.1.1.3 RECIPE STEP ACID WASH 26 1.4.2.1.2 RECIPE STEP CAUSTIC WASH 27 1.4.2.1.3 RECIPE STEP RACK RINSE 28 1.4.2.1.4 RECIPE STEP ACID RECOVERY 28 1.4.2.1.5 RECIPE STEP CAUSTIC RECOVERY 29 1.4.2.1.6 RECIPE STEP TIMED SOAK 29 1.4.2.1.7 RECIPE STEP CONFIRMED PAUSE 29 1.4.2.1.8 RECIPE STEP TRIGGER ACID REFRESH 30 1.4.2.1.9 RECIPE STEP TRIGGER CAUSTIC REFRESH 30 1.4.2.1.10 RECIPE STEP SKIP STEP 30 1.4.2.2 CIP SYSTEM NON-RECIPE OPERATION 31 1.4.2.2.1 ACID MAKE CYCLE 31 1.4.2.2.2 CAUSTIC MAKE CYCLE 32 1.4.2.2.3 ACID TANK FLUSH 33 1.4.2.2.4 CAUSTIC TANK FLUSH 34 1.4.2.2.5 SOLUTION VALIDITY FUNCTIONALITY AND FORCE VALIDITY 34 1.4.2.2.6 SEMI-AUTOMATIC TRANSFERS 35 1.4.3 SUPPORTING EQUIPMENT IN AUTOMATIC MODE 35 1.4.3.1 PLANT CONTROL OVERVIEW 35 1.4.3.1.1 PLANT FLOW REFERENCE 35 1.4.3.1.1.1 CLEARWELL LEVEL 36 1.4.3.1.1.2 HMI FLOW SETPOINT 36 1.4.3.1.2 PLANT FLOW REFERENCE DISTRIBUTION 36 1.4.3.1.2.1 RACK FLOW REFERENCE 36 1.4.3.1.2.2 FEED PUMP FLOW REFERENCE 37 1.4.3.2 FEED PUMP CONTROL 37 1.4.3.2.1 FLOW CONTROL 37 1.4.3.2.2 PRESSURE CONTROL 38 1.4.3.2.2.1 AUTO PRESSURE ADJUST FOR TMP 38 1.4.3.3 RF FLOW CONTROL 39 4 PALL MICROFILTRATION SYSTEM
1.4.3.4 AUTOMATIC FEED STRAINERS 39 1.4.3.5 AIR COMPRESSORS AND RELATED EQUIPMENT 42 1.4.3.5.1 PLC/COMPRESSOR SIGNALS 42 1.4.3.5.2 CONTROL 43 1.4.4 MANUAL MODE OPERATION 44 2 GLOSSARY 45 APPENDIX A: FILTER RACK VALVE AND DEVICE FUNCTION DESCRIPTIONS 48 APPENDIX A: FILTER RACK VALVE TRUTH TABLES 50 APPENDIX B: MF SYSTEM OPERATIONAL PROTOCOL 52 APPENDIX A FILTER RACK VALVE AND DEVICE FUNCTION DESCRIPTIONS AND VALVE TRUTH TABLES APPENDIX B OPERATIONAL PROTOCOL APPENDIX C SETPOINT LIST Pall Microfiltration System 5
REVISIONS TABLE A PALL CORPORATION REVISION HISTORY Revision Date Originator Description 00 Dec 02, 2010 M.Montag Initial Release. 6 PALL MICROFILTRATION SYSTEM
1 MIICROFIILTRATIION SYSTEM OPERATIION 1.1 INTRODUCTION (For additional information on valves, devices, and equipment identified by tag number in the text of this document, please refer to Pall P&ID Drawing 1000026753.) This Pall Corporation Microfiltration (MF) System is designed to filter up to 6.7 million gallons of water daily. Additional modules can be purchased and installed for increased capacity. Pall Corporation is supplying a system comprised of 4 filter racks, 3 feed pumps, 2 reverse filtration pumps, CIP equipment, compressed air equipment, valves, instruments, and control equipment required for system operation. Raw water is delivered to the MF system by the 3 feed pumps. Variable frequency drives (VFD s) on the pumps control the feed manifold pressure or flow by varying pump speed. Ville de Carignan PALL MEMBRANE MICROFILTRATION SYSTEM 7
The feed water passes through automatic backwashing strainers, then through the microfiltration system filter racks. Each rack has a number of automatic sequences that are described below. During operation, regeneration of the membranes is accomplished by four methods: Air Scrubbing (AS), Feed Flush (FL), Enhanced Flux Maintenance (EFM), and Clean in Place (CIP) chemical cleaning. Filtrate from the module racks flows to the finished water clearwell (T-4007). NOTE Throughout this document, Bold Italic Text indicates operator adjustable setpoints. Modes and processes appear as Bold Text. Graphic buttons on HMI screens are Framed, while the screens appear in Bold, Underlined Text. For additional information on valves, devices, and equipment identified by tag number in the text of this document, refer to the supplied Pall Process and Instrument Diagram (P&ID) drawing. CAUTION All Pall Corporation Microfiltration System operators must be properly trained by Pall Corporation or someone authorized by Pall Corporation. Any damage to any part of the Pall Corporation Microfiltration System caused by an untrained operator voids all warranties. Additionally, any damage to any part of the Pall Corporation Microfiltration System caused by modifying or loading computer software onto the Pall Corporation Microfiltration System computers unauthorized by Pall Corporation voids all warranties. 8 PALL MICROFILTRATION SYSTEM
1.2 THE MICROFILTRATION (MF) SYSTEM PROCESSES Automatic or Auto mode operation is the normal system operating mode. In Auto mode, the system PLC controls setpoints and functions for each rack. Auto mode includes the following processes: Fill Auto Filter or Forward Flow (FF) (production of filtrate) Air Scrub (AS) Feed Flush (FL) Drain Enhanced Flux Maintenance (EFM) Integrity Test (IT) Clean in Place (CIP) CIP process is a special sequence used to chemically clean the modules. The use of this sequence is infrequent; typically the design CIP interval is between 14 and 30 days. Descriptions of these processes are included in the functional description portion of this manual. 1.3 PROGRAMMABLE LOGIC CONTROLLER (PLC) MODES 1.3.1 DEFINITION Throughout the process, mode control is used to enable/disable pieces or groups of equipment in order to provide operational flexibility. Mode control occurs at the lowest defined unit level. NOTE Mode control is strictly a software function and cannot bypass or replace hardwired controls and interlocks. Pall Microfiltration System 9
1.3.2 GROUPING If the smallest defined unit is the whole unit, the whole unit has one common mode control. If the smallest defined unit is a subunit, each sub-unit has its own mode control. 1.3.3 MODES 1.3.3.1 AUTO In Auto mode, all equipment in the unit/sub-unit is controlled according to the state of the logic sequencing software. In most cases, changing the mode to Auto enables the equipment to start through a process sequence that usually requires the operator to select a process start pushbutton. In some cases, however, the equipment may start immediately on entering Auto mode if the logic so requires. 1.3.3.2 MANUAL In Manual mode, the operator may cycle valves or turn on or off the equipment as desired from the control room HMI. Note that all actuated rack valves (including block and bleed valves) are furnished with proximity-type limit switches to indicate confirm open/closed position. The off-rack valves do not have limit switches. These would include Feed, CIP and Filtrate area valves. The filter racks each have I/O modules, which communicate with, and are controlled by, the system PLC. 10 PALL MICROFILTRATION SYSTEM
CAUTION Manual mode is not recommended as it overrides all automatic equipment functions and can adversely affect the microfiltration equipment, process, and results. The system operator is solely responsible for the outcome of system functioning while in Manual mode. Operators should NOT use Manual mode unless trained to operate the microfiltration system in Manual mode by Pall Corporation or someone authorized by Pall Corporation. 1.3.3.3 DISABLE Selecting Disable mode results in all valves being closed and disabled. No further manipulation of the equipment can be made from the HMI automated processes are not available and individual devices cannot be operated manually. 1.3.4 MODE SELECTION Mode Select Operator Selection Auto Manual Disable Enable Process Selection and Cycle Start Allow Individual Device Control Via HMI Set All Devices To OFF Pall Microfiltration System 11
1.4 FILTER RACK UNIT 1.4.1 FILTER RACK AUTOMATIC MODE OPERATION During normal operation, all racks are on line, i.e. in Auto Mode and processing water in Forward Flow (FF). However, the operator may take one or more of the filter racks off line in order to perform a CIP or a maintenance function. All enabled racks in Auto mode operate with identical parameters, including process and alarm setpoints, timer and volume presets, etc. However, a test mode is available to allow rack to operate with certain parameters independently, for performance testing purposes. To place a rack in Auto mode, the rack graphic is selected and the AUTO pushbutton is selected. To start the filtration process, the AUTO FILTER pushbutton is selected. Note that Auto Filter is only enabled if the system is capable of processing water, and the plant itself is enabled to run. The Auto Filter process first sequences through a Fill cycle, then enters Forward Flow (FF). During FF, a volume totalizer keeps track of the filtrate flow through the rack and, after reaching a preset value, requests permission from the system PLC to perform a Flux Maintenance (FM). Upon receiving permission and performing these cycles, the rack again enters FF. Occasionally, based on time of day or operator intervention, the rack also performs an Integrity Test, which assures that the membranes are still performing reliably. Details of each step follow. 1.4.1.1 FILL SEQUENCE The Fill sub-cycle purges the piping and modules of air before the rack enters Forward Flow. To effectively purge air from all of the enabled module racks, the racks are placed on-line, one at a time (manually selected by the operator), according to the sequence described below. The rack will perform a Fill sequence automatically before entering production under the following conditions: The last cycle performed was a Drain or IT The rack was taken out of Auto mode 12 PALL MICROFILTRATION SYSTEM
Or A CIP drain or chemical recovery step was performed without a follow up rinse. An adjustable Fill Cycle Watchdog timer checks to make sure the Fill cycle sequence takes place in a reasonable amount of time (approximately two minutes or less). If the timer times out, the rack shuts down, and the operator is alerted to the problem by an alarm message on the HMI. 1.4.1.1.1 INITIAL STARTUP If the feed manifold is empty, the system should be started up with the Feed pumps in Manual mode. Once the feed manifold is full of water, the Feed Pump system may be left in Auto Mode, and the pumps start on demand from the racks. 1.4.1.1.2 FILL CYCLE 1. At the start of the Fill cycle, all on-rack automated valves are closed. The normal position for off-rack automated block and bleed valves is to allow forward flow and provide air gaps in the CIP piping. 2. Feed Block valve (V-1030) and Filtrate Block valve (V-1025) are open, as are the CIP Supply Bleed valve (V-1022) and the CIP Return Bleed valve (V-1014). This is changed only when the CIP piping used during a CIP or EFM. 3. At the filter rack, Upper Drain valve (V-1010) is opened, venting the feed side of the modules to drain; Feed Flow Control valve (FCV-1001) is opened to a present FCV Fill Position to introduce feed water to the module rack. 4. The flow through the Feed Flow Transmitter (FIT-1005) is totalized. 5. After the Feed Fill Volume is processed, the Filtrate valve (V-1018) opens and after it proves open the Upper Drain valve (V-1010) closes. Filtrate Vent valve (V-1017) can be used instead of the Filtrate valve if plant configuration dictates. Pall Microfiltration System 13
6. After an additional Filtrate Fill Volume is processed, a short stabilization hold is performed for Min Time for Flow Stabilization. 7. At this time the rack transitions to Forward Flow. The Fill Volume setpoints allow site-specific customization. Once an effective Fill Volume is established during start-up (rack filled and minimized vent drainage), these parameters do not normally require adjustment. 1.4.1.2 FORWARD FLOW After each rack completes the Fill cycle, it is then operating in Forward Flow. This is the filtration process, and is the primary operating cycle for the racks. 1. The Filtrate Outlet Valve (V-1018) opens to begin Forward Flow (it may have been opened in a previous cycle, such as the Fill cycle). 2. At the start of Forward Flow, the Feed Flow Control Valve (FCV-1001) PID loop is put in Manual and the valve is automatically opened to the same position it was in when last operating in Forward Flow. 3. When flow through the rack has time to stabilize (15 seconds fixed), at a predetermined flow rate for a fixed amount of time, the feed flow PID control is put in Auto mode. Feed Flow Control Valve (FCV-1001) controls the filtrate flow through each rack. During Forward Flow operation, the Filtrate Valve (V-1018) is open, and Feed Flow Control Valve (FCV-1001) modulates as required by the PID loop to maintain the Rack Flow setpoint. See Section 4.5.4.1.2.1 Rack Flow Reference - for information on how the rack PID reference is generated. 1.4.1.3 FLUX MAINTENANCE Each filter rack periodically executes Flux Maintenance procedures. A Flux Maintenance cycle is an AS (Air Scrub with Filtrate) followed by a Feed Flush (FL). The Flux Maintenance 14 PALL MICROFILTRATION SYSTEM
frequency is based on the totalized filtrate flow volume through each rack compared to the Flux Maintenance Interval Volume setpoint. The program for each individual rack will compute filtrate flow volume between cycles by measuring the filtrate flow through the rack, determined from the Feed Flow Transmitter (FIT-1005), and converting to volume at one-second intervals. Ideally, the volume of water processed between each regeneration cycle should remain the same. For example, if the running average flow rate decreases, the interval between regeneration cycles will increase. At design conditions, the interval will range from 15 to 30 minutes. During low flow conditions, this period may be as long as 3 hours. Operators will have the ability to set the Flux Maintenance Interval Time (in minutes), which will override the treated volume setpoint described above. The Flux Maintenance cycle sequencing follows: 1.4.1.3.1 AIR SCRUB (AS) The Air Scrub process is used to physically remove particulate buildup on the feed side of the module fibers. The AS process is then followed by a Flush cycle. When a particular rack requests an Air Scrub, the sequence progresses as follows: 1. The system checks the air pressure in the receiver to ensure that the AS Minimum Air Pressure is at or above the proper air pressure. This is accomplished by reading the PIT-6011 before the AS process can begin. 2. The PLC stores the position of Feed Flow Control Valve (FCV-1001) for use when going back to Forward Flow. 3. The Feed Flow Control Valve (FCV-1001) and the Filtrate Valve (V-1018) close, isolating the rack from the system. 4. Upper Drain Valve (V-1010) opens. 5. Water will now be introduced, in addition to airflow, to enhance the cleaning of the module fibers, and to flush away dislodged particles. The rate during the AS cycle is determined by the AS Water Flow Rate setpoint. Pall Microfiltration System 15
6. The RF Supply valve V-1013 opens, FCV-1001 remains closed, and the RF flow pump P-4302A or P4302B starts. The system PLC uses a PID loop to adjust the pump speeds for pumps P-4302A & B to maintain the AS Flow Rate through FIT-4305. 7. Once a minimum flow is reached, the Air Supply Valve (V- 1006) will open. A PID loop will modulate either FCV-6034A or FCV-6034B to control air flow rate at AS Air Flow Rate. 8. This step continues for AS Cycle Time (a typical duration of 60 seconds). 9. When the AS Cycle Timer times out, the Air Supply valve (V- 1006) closes, and the RF pumps stop and air flow control valves close. 1.4.1.3.2 FLUSH (FL) CYCLE A Flush cycle follows each AS cycle. 1. The Upper Drain Valve (V-1010) remains open from the AS step, and Feed Flow Control Valve (FCV-1001) modulates to maintain the flow via the Feed Flow Transmitter (FIT-1005) at the Flush Flow Rate. The Flush Flow Totalizer begins totalizing the flow through FIT-1005. The Feed Flow Control Valve position when last in Forward Flow is still retained by the PLC for later use when the filter rack returns to Forward Flow. 2. When the Flush Flow Totalizer reaches the Flush Volume, the Filtrate Valve (V-1018) opens. Then Upper Drain Valve (V-1010) closes and the FCV-1001 PID loop is put in Manual mode. 3. When Upper Drain Valve (V-1010) proves closed, the rack proceeds to Forward Flow (refer to Section 1.4.1.2 Forward Flow (FF) ). 1.4.1.3.3 REVERSE FILTRATION (RF) CYCLE A Reverse Filtration (RF) cycle is performed when selected by the operator. During the RF cycle, filtrate is forced through the 16 PALL MICROFILTRATION SYSTEM
membranes in the reverse direction. The objective during this cycle is to flow in the reverse direction,. A typical duration is 20 to 30 seconds. RF Supply Flow Transmitter monitors the RF (reverse direction) flow rate. When a RF cycle for a particular filter rack is initiated, the filter rack is isolated from the feed manifold and the RF cycle proceeds according to the following sequence: 1. The flow rate during the RF cycle is determined by the RF Flow Rate setpoint, as input by the operator. The PLC maintains the RF flow rate by controlling the speed of RF Pumps P-4302 (A-B). A PID loop controls the pump speed to maintain the RF flow. The loop starts in Manual at the previous speed of the last RF sequence. If this is the first sequence the speed initializes to 10%. The loop remains in Manual for a fixed amount of time (approximately 5 seconds) to allow the flow to stabilize before being placed into Auto. The PLC must maintain the setpoints individually for each rack, since the pressure requirements vary from rack to rack. 2. At the start of the RF cycle the Feed Flow Control Valve (FCV-1001) and the Filtrate Outlet Valve (V-1018) close. 3. After these valves prove closed, the Lower Drain Valve (V- 1002), the Upper Drain Valve (V-1010), and the RF Supply Valve (V-1013) on the rack open, and the RF Pumps P-4302 (A-B) starts ramping up to the previous speed of the last RF sequence. The PLC alternates which pump starts for each RF cycle based on runtime hours (lowest runtime pump is used). The VFD controlling the pump is set to ramp up to speed in about 6 seconds (ramp speed is adjustable). After about 5 or 6 seconds the RF PID loop will be put in Auto to control the pump speed for the duration of the RF cycle. 4. Flow is totalized through RF Flow Transmitter (FIT-4305). Once the RF Cycle Volume is reached, the RF Pump (P- 4302 A-B) ramps to a stop and the Lower Drain Valve (V- 1002), the Upper Drain Valve (V-1010), and the RF Supply Valve (V-1013) close. 5. The rack flow totalizer resets to zero volume. Pall Microfiltration System 17
6. When the rack valves prove closed, the rack returns to Forward Flow by opening the Filtrate Outlet Valve (V-1018) and setting FCV-1001 to the position it held during the last RF cycle. 7. The rack is now processing in Forward Flow (Section 1.4.1.2). 1.4.1.4 INTEGRITY TEST (IT) On a regular basis, the integrity of the filters must be tested to ensure that there are no leaks in the membrane fibers. This Integrity Test can be performed on a regular basis automatically, or at the operator s discretion. If performed automatically the test is performed on either Hours Between Integrity Tests or Days Between Integrity Tests basis. Hours Between is used if Days Between is zero; otherwise Days Between takes precedence. If Days Between is used, the rack will be marked as needing an IT after the number of days has elapsed, and the Integrity Test Auto Start Hours and Integrity Test Auto Start Minute has passed. If Hours Between is the active setpoint, the rack will totalize the number of hours since the last IT, even if not running, and once the time elapsed has exceeded the setpoint, the rack will be marked as needing an IT. Racks will perform ITs automatically after the next naturally occurring FM cycle, if they are marked as needing one and all other permissive conditions are satisfied. However they are enabled, each enabled rack will perform an IT, one at a time, until all racks have completed the process. During IT pressurization and stabilization, Flux Maintenance procedures are not allowed on the racks. While the first filter rack is in the later pressure hold step of its IT, the other racks are allowed to perform Flux Maintenance procedures. Eventually, all filter racks in the system receiver their scheduled IT. If performed at operator request, the operator may select any active rack. The test is performed immediately, unless the rack 18 PALL MICROFILTRATION SYSTEM
selected is in a FL or AS cycle, in which case the test is performed immediately after the completion of the cycle. Only one rack may be placed in Manual IT at a time. The IT is a pressure decay test. The extremely small pores in the module fibers do not allow free passage of undissolved air through the membrane. Therefore, if one side of the module is pressurized with compressed air, and then isolated, the pressurized side should maintain nearly constant pressure if the membrane has no flaws. However, if one or more of the modules being tested has broken fibers, the air is allowed to pass through to the other side of the membrane, and the pressure on the highpressure side decreases. 1. To start the test manually, the operator selects the rack graphic and selects Integrity Test from the rack control popup. The first step of the sequence is the closing of the Feed Flow Control and Filtrate Valves (FCV-1001 and V-1018) and the opening of the Upper Drain Valve (V-1010). 2. The IT Air Valve (V-1096) opens, admitting compressed air to the filtrate side of the modules. 3. As the air enters the modules, it displaces the water from the upper filtrate manifolds, as well as from the inside of the fibers through the module to the feed side, and then out the Upper Drain. When all the water is displaced, the pressure reading on Filtrate Pressure Transmitter (PIT-1021) increases above the Minimum IT Pressure (25 PSI), and then stabilizes. 4. The system waits for pressure at the Filtrate Pressure Transmitter (PIT-1021) to stabilize, as determined as less than 0.04 PSI change within 60 seconds, thought the stabilization setpoints are adjustable. 5. IT Air Valve (V-1096) and Upper Drain (V-1010) close, and the CIP Return Valve (V-1015) opens to disconnect from the pressurized drain, and the rack goes through pressure stabilization. The system waits for pressure at Filtrate Pressure Transmitter (PIT-1021) to stabilize, determined as less than 0.04 PSI change within 60 seconds, though again the stabilization parameters are adjustable. Pall Microfiltration System 19
6. At this time, a timer starts and runs for the IT Pressure Decay Test Time. (typically 5 minutes). The pressure at Filtrate Pressure Transmitter (PIT-1021) is recorded. For the remaining test time, the current pressure is compared to this benchmark. If, during this time, the pressure at Filtrate Pressure Transmitter (PIT-1021) does not decrease by more than the IT Maximum Pressure Decay (about 0.20-0.30 PSI), the rack passes. The actual decay value is recorded by the HMI. 7. The CIP Return Valve (V-1015) closes, and Filtrate Vent Valve (V-1017) opens, venting the rack pressure. To prevent rapid (and noisy) release of air, the Filtrate Vent Valve (V-1017) cycles open and closed at no more than 1- second intervals, until the rack pressure is reduced below the IT Vent Maximum Pressure. 8. When Filtrate Pressure Transmitter (PIT-1021) reads less than the IT Vent Maximum Pressure, the rack performs a Fill cycle, and then goes back to Forward Flow. 9. If, however, the pressure decreases by more than the target before the timer times out, and the operator has selected Shutdown on IT Failure, an alarm message is displayed to this effect, and the rack is taken off line (after the pressure relief and Fill cycles) for further operator action. Typically, a second Integrity Test should be performed manually to confirm the results. If Shutdown on IT Failure is not selected, the system issues a Warning to the operator, and the rack goes back on-line as normal. 1.4.1.5 ARBITRATION The PLC contains a ticketing system to coordinate the execution of the Flux Maintenance (AS & FL) and EFM and IT cycles. The PLC rack program totals the flow through the rack between FM cycles. It determines when an FM is due by comparing the total to the Flux Maintenance Interval Volume. When a rack is ready to perform an FM, an internal flag is set which triggers the FM Arbitration to assign the next available FM ticket. When a rack completes an FM, its ticket is released, and the arbitration routine decrements all remaining tickets, allowing the next rack to 20 PALL MICROFILTRATION SYSTEM
proceed. The rack requesting the cycle first will take precedence. It is possible that all racks might hold a ticket for Flux Maintenance, and the program must accommodate this circumstance. NOTE The FM arbitration is blocked when another rack finishes up with an EFM or a CIP, and that rack is required to perform an immediate FM cycle. The rack presently in an FM sequence is allowed to finish, but the arbitration does not advance until the EFM/CIP rack has finished its required FM. When the arbitration selects the next rack to perform an FM, the rack must wait for specific permissive to be met, depending on the sequence to be performed. For an AS to be performed, the following permissive must be met: 1. The air receiver must be at or above the Minimum Pressure for Air Scrub 2. Any IT sequence running must be finished with its use of the air system. 1.4.1.6 INDIVIDUAL FILTER RACK SHUTDOWN If, while the membrane system is in operation, a specific rack must be shut down for troubleshooting or maintenance, the operator has a variety of options available at the HMI: Process Stop in Auto Mode Keeping the rack in Auto Mode but selecting Stop simply closes the on-rack feed and filtrate, valves. No rack draining occurs. The operator keeps the option to perform other automated processes such as an AS, RF (Reverse Filtration), IT, etc assuming the permissives for those sequences are true. Pressing Stop will cause the rack to enter a Stop sequence, which will shut the rack down in a controlled manner, to prevent water hammer. Pall Microfiltration System 21
Disable Selecting this Mode results in the closure of all valves, and no further manipulation of the rack equipment can be made from the HMI other automated processes are not available and individual valves cannot be operated manually. The rack must be stopped (idle) for disable to be available. Manual Selecting this Mode results in the closure of all valves, but individual valves can be selected and operated. The automated processes are not available. The rack must be stopped (idle) for manual to be available. CAUTION A chlorine residual must be maintained in the water held in any disabled rack if it is shut down for one day or longer. Failure to perform correct shutdown, lay-up, and restart procedures voids the Pall Corporation MF System warranty. 1.4.2 ENHANCED FLUX MAINTENANCE (EFM) AND CLEAN-IN-PLACE (CIP) The EFM and CIP processes both use the same equipment and are recipe driven. EFM is an automatically scheduled and unattended cleaning process, typically of shorter duration than a CIP, which is operator initiated and operator managed. The mode that the system is operating in (EFM or CIP) is contained within the loaded system recipe. If an EFM recipe is loaded, the system is set to operate in EFM mode, and vice versa. Additionally, the loaded recipe determines the chemical makeup parameters for acid and caustic solutions. The chemical makeup parameters in the recipe are compared with those used to actually make up the contents of the tanks, and this comparison is used to actually make up the contents of the tank, and this comparison is used to determine chemical validity i.e., is the solution proper for use by the currently loaded recipe. The operator can force the chemical validity from the acid and caustic popups. In addition to chemical validity, the tank solutions are checked for temperature range, minimum volume, and number of washed performed before being valid for use. 22 PALL MICROFILTRATION SYSTEM
If the acid and caustic solution is not chemically valid, the operator can force validity (indicating that they are willing to use the existing solution no matter what its chemical makeup), or a chemical makeup using the recipe parameters can be triggered. This will automatically drain the existing solution at the operator s option. Additionally, a full chemical make will reset the number of washes used. Both the EFM and CIP processes can use any recipe stop described in the following sections. Multiple recipes can be defined for each type, and the recipe that is desired is loaded prior to starting EFM or CIP procedures. In the case of EFM, normal procedure is to load the desired EFM recipe, prepare the EFM solutions, and leave the system prepared for automatic EFM execution. 1.4.2.1 ENHANCED FLUX MAINTENANCE (EFM) In addition to membrane regeneration by periodic application of AS, FL, and RF cycles, another effective technique for maintaining low Transmembrane Pressure (TMP) and high flux is Enhanced Flux Maintenance (EFM). The EFM cycle is an automatic process, programmed to occur after an operatordefined volume of treated water has been processed. A typical EFM duration is 45 90 minutes per filter rack. The EFM process is a recipe driven sequence defined by a set of operator-input parameters that are maintained in the recipe and downloaded to the PLC for use. The EFM sequence typically includes warm water and chlorine. However, since the EFM is recipe driven, different recipes can be created to perform caustic/chlorine only EFM, or acid only EFM, or even a 2-part EFM with caustic/chlorine followed by acid. All of the steps available for CIP operations can be used by an EFM recipe, keeping in mind that no operator prompts are issued in EFM mode. Some additional points regarding the EFM process: The EFM process uses the same system equipment as the Clean-In-Place (CIP) process. An EFM procedure on one rack requires an interruption of Forward Flow of approximately 45 90 minutes. During that time, the remaining racks continue in Forward Flow and Pall Microfiltration System 23
perform other Flux Maintenance routines. Only one rack may perform an EFM at a time. CAUTION When working with any chemicals, always follow appropriate safety procedures. When the system is in EFM mode, the EFM Interval Volume setpoint determines when an EFM is triggered on a particular rack. When the volume through the rack, as totalized by FIT-1005, is greater then the EFM Interval Volume setpoint, a flag will be set indicating the rack needs to schedule an EFM. After the next regularly scheduled FM, if this flag is set, the system will check that the CIP systems are ready to start an EFM. If the system is ready to perform an EFM, the rack will start an EFM following the next naturally occurring FM, and the EFM recipe will be initiated as described below. EFM will not start unless the solution used in the loaded recipe are valid, and not spent (too many washes), are within the defined temperature range, and there is enough volume in each to fill the rack. All four CIP areas must be in auto, along with the CIP circulation and drain pumps. EFM must also be enabled on the rack. The remake of EFM solution is not entirely automatic, but is triggered via a recipe steps. The steps listed below will be performed based on the sequences in the recipe. When an EFM recipe is completed, the rack is put in the FM queue and will perform an AS/FL combination as soon as possible. At that time, it will return to FF (production filtering). 24 PALL MICROFILTRATION SYSTEM
1.4.2.1.1 CLEAN-IN-PLACE (CIP) The CIP cycle is a semi-automatic process initiated by an operator when desired. This operation may be performed on one rack, or sequentially on all the racks. The CIP process is defined by operator-programmed sequences, or recipes, which are maintained in the HMI computer. Prior to initiating a CIP, the operator will select which recipe is to be used. All of the steps within the CIP process will be defined within the recipe; including event durations, flow rates, etc. An operator will be able to create or modify recipes as required. Some miscellaneous points regarding the CIP process: A CIP procedure on one rack requires approximately 3-4 hours in total. Based on previous experience, typically up to 4 rack cleanings can be performed with one batch of CIP solution (both caustic/chlorine and acid). This is dependent on the feed water condition. This can only be determined through experimentation once the system is on line. Only one rack can execute a CIP or EFM at one time. The steps listed below will be performed based on the sequences in the recipe. When a CIP recipe is completed, the rack is put in the FM queue and will perform an AS/FL combination as soon as possible. At that time, it will return to an idle state. 1.4.2.1.1.1 EFM AND CIP RECIPE STEPS The following steps are available to be used in both EFM and CIP type recipes. In EFM operation, no operator prompts are displayed except the deliberate operator confirmed prompt step. In all other places where prompts would appear, the prompt is skipped, and if it is a decision, the default choice is automatically made. Pall Microfiltration System 25
No pre-configured rack drain is done prior to recipe start. The rack must be drained of water, so the first step in any recipe should be a drain of some kind. As soon as the recipe sequence begins, the rack block and bleed valves are switched to the CIP positions and confirmed, opening air gaps between lines filled with chemical and the headers. If not in EFM mode, the system prompts to confirm step process start. Following confirmation, the system processes the recipe steps in order. Any undefined step will end the recipe processing. 1.4.2.1.1.2 RECIPE STEP PUMPED DRAIN TO CHEMICAL DRAIN The system reserves the area for sequence use, ensuring other sequences cannot simultaneously use the equipment. The rack CIP Supply valve (V-1003), Filtrate Vent (V-1017), CIP Return valves (V-1015 and V-1012), CIP Return Bleed (V-1014) valves are opened, and the CIP Return Block valve (V-1029) are closed. This arrangement allows drainage out the bottom of the rack and air relief on the top. Off-rack valve V-5217 is opened to provide a path to the Chemical Drain. The Drain Pump P-5214 is run for the recipe-driven drain time, and may be stopped and restarted multiple times if this is required to drain the rack. Once it is determined that the rack is drained, the pump is stopped, and all previously opened valves are closed. A completed pumped drain will reset the flag indicating that there is chemical in the rack. 1.4.2.1.1.3 RECIPE STEP ACID WASH The system reserves the Acid area for use, and checks that the solution temperature and volume are within setpoint limits (acid setpoints MINIMUM TEMP FOR CIRCULATION, MAXIMUM TEMP FOR CIRCULATION, and MINIMUM VOLUME FOR CIRCULATION). The CIP Supply (V-1003) and CIP Feed Return (V-1015), and depending on step chosen CIP Filtrate Return (V- 1012) valves are opened on the rack and confirmed. 26 PALL MICROFILTRATION SYSTEM
Acid Tank Outlet (V-5132), Acid Tank Return (V-5212), and Circ Pump Block (V-5282) valves are opened to create a path to circulate acid solution. Inappropriate off-rack valves are closed. CIP Circulation Pump P-5204 is started and run for the recipedriven wash duration (in minutes). If, during the wash, the temperature as measured by TT-5107 rises above the maximum temperature setpoint, the pump is stopped and the process is paused until the temperature returns below the maximum. At the end of the recipe wash time, the pump is stopped, the offrack valves are closed, and the acid area reservation is released. The on-rack valves are left open, as that configuration is default for all recipe steps. 1.4.2.1.2 RECIPE STEP CAUSTIC WASH The system reserves the Caustic area for use, and checks that the solution temperature and volume are within setpoint limits (caustic setpoints MINIMUM FOR CIRCULATION, MAXIMUM TEMP FOR CIRCULATION, and MINIMUM VOLUME FOR CIRCULATION). The CIP Supply (V-1003) and CIP Return (V-1015), and depending on step chosen CIP Filtrate Return (V-1012) valves are opened on the rack and confirmed. Caustic Tank Outlet (V-5025), Caustic Tank Return (V-5213), and Circ Pump Block (V-5282) valves are opened to create a path to circulate caustic solution. Inappropriate off-rack valves are closed. CIP Circulation Pump P-5204 is started and runs for the recipedriven wash duration (in minutes). If, during the wash, the temperature is measured by TT-5007 rises above the maximum temperature setpoint, the pump is stopped and the process is paused until the temperature returns below the maximum. At the end of the recipe wash time, the pump is stopped, the offrack valves are closed, and the caustic area reservation is released. The on-rack valves are left open, as that configuration is default for all recipe steps. Pall Microfiltration System 27
1.4.2.1.3 RECIPE STEP RACK RINSE The system reserves the area for sequence use, ensuring other sequences cannot simultaneously use the equipment. The CIP Supply (V-1003) and CIP Return (V-1015), and depending on step chosen CIP Filtrate Return (V-1012) valves are opened on the rack and confirmed. Circulation Block (V-5282), Return Header to Chemical Drain (V-5242) and Potable Rinse (V- 5227) valves are opened to allow rinse water to flow through the non-operational circulation pump, through the rack, and into the Chemical Drain. The flow through the rack flowmeter FIT-1005 is totalized until the recipe-driven rinse volume is counted. A completed rinse will reset the flag indicating that there are chemicals in the rack. The off-rack valves are then shut. 1.4.2.1.4 RECIPE STEP ACID RECOVERY This step recovers the fluid in the rack to the Acid Tank. The system reserves the Acid area for sequence use, ensuring other sequences cannot simultaneously use the equipment. Rack valves remain in or are moved to CIP positions, with V-1003, V-1015, and V-1012 open, and the block and bleed valve sets configured for CIP use. Inappropriate off-rack valves are closed and Drain Pump to CIP Supply Header (V-5289), Acid Tank Outlet (V-5132), and Acid Tank Return (V-5212) valves are opened, allowing fluid pumped from the rack by the drain pump to be returned to the tank via the outlet valve. CIP Drain Pump P-5214 is run for the recipe-driven drain time. The drain pump may stop and restart multiple times in order to fully drain the rack. When it is determined that the rack is properly drained, the drain pump is turned off, and the off-rack and rack valves are closed. 28 PALL MICROFILTRATION SYSTEM
A completed recovery will reset the flag indicating that there are chemicals in the rack. 1.4.2.1.5 RECIPE STEP CAUSTIC RECOVERY This step recovers the fluid in the rack to the Caustic Tank. The system reserves the Caustic area for sequence use, ensuring other sequences cannot simultaneously use the equipment. Rack valves remain in or are moved to CIP positions, with V-1003, V-1015, and V-1012 open, and the block and bleed valve sets configured for CIP use. Inappropriate valves are closed, and Drain Pump to CIP Supply Header (V-5289), Caustic Tank Outlet (V-5025), and Caustic Tank Return (V-5213) valves are opened, allowing fluid pumped from the rack by the drain pump to be returned to the tank via the outlet valve. CIP Drain Pump P-5214 is run for the recipe-driven drain time. The drain pump may stop and restart multiple times in order to fully drain the rack. When it is determined that the rack is properly drained, the drain pump is turned off, and the off-rack and rack valves are closed. A completed recovery will restart the flag indicating that there are chemicals in the rack. 1.4.2.1.6 RECIPE STEP TIMED SOAK The process holds for the recipe-driven pause time (in minutes). 1.4.2.1.7 RECIPE STEP CONFIRMED PAUSE In this step, the prompt system requests simply that the operator confirm continuation of the process. Pall Microfiltration System 29
1.4.2.1.8 RECIPE STEP TRIGGER ACID REFRESH This step starts the refresh process on the Acid Tank, and ensures that it starts, then moves on to the next step. It does not wait for the refresh to complete. The Refresh process adds water up to the recipe-driven Acid Make Water Volume, and adds the recipe-driven Acid Refresh Acid Volume to the tank. If, however, the Acid solution has been used for more wash procedures than the recipe Acid Solution Washes Allowed setpoint, the refresh will instead jump to a full make procedure, which includes a drain. A full make procedure will reset the solution wash counter and thus allows the solution to return to validity. 1.4.2.1.9 RECIPE STEP TRIGGER CAUSTIC REFRESH This step starts the refresh process on the Caustic Tank, and ensures that it starts, then moves on to the next step. It does not wait for the refresh to complete. The Refresh process adds water up to the recipe-driven Caus Make Water Volume, and adds the recipe-driven Caus Refresh Caus Volume and Caus Refresh NaOCI Volume to the tank. If, however, the Caustic Solution has been used for more wash procedures than the recipe Caus Solution Washes Allowed setpoint, the refresh will instead jump to a full make procedure, which includes a drain. A full make procedure will reset the solution wash counter and thus allows the solution to return to validity. 1.4.2.1.10 RECIPE STEP SKIP STEP This step does nothing but skip to the next step. It can be used to put gaps in the recipe without causing a shutdown (an undefined step will end the recipe). 30 PALL MICROFILTRATION SYSTEM
1.4.2.2 CIP SYSTEM NON-RECIPE OPERATION 1.4.2.2.1 ACID MAKE CYCLE The operator initiates the automatic preparation of CIP or EFM solutions at the HMI by selecting the tank graphic and selecting the ACID MAKE button. After the first batch has been made by a manual initiation by the operator, the remake of the tank solutions can occur automatically if a recipe REFESH step is run. If a REFRESH is triggered and the solution is already spent (too many washes), a full MAKE process is triggered instead of the limited REFRESH. The ACID MAKE sequence is as follows: The Acid CIP Tank Water Supply Valve (V-5109) opens to fill the Acid CIP Tank with potable water. The PLC will close the valve when the tank level reaches the recipe Acid Make Water Volume, as measured by Acid CIP Tank Level Transmitter (LIT- 5106). While the tank is filling, the Acid CIP Tank Heater (H-5104) will be disabled until the tank level is above the Heater Enable Level setpoint. The heater will turn on when the tank temperature is below the Temperature setpoint by more than the Temperature Deadband as measured by the Acid CIP Tank Temperature Transmitter (TT-5107). The heater will turn off when the tank temperature is above the Temperature setpoint. If should be noted that the heater control is always active as long as the heater is in automatic mode if the level is high enough, the heater will always be trying to maintain the requested temperature, if in auto. While the Acid Tank is still filling but almost full of potable water, the PLC instructs the Acid Supply Pump P-5115 to deliver the recipe Acid Make Acid Volume into the tank via the acid supply valve (V-5124). The Make sequence completes when all of the required water and acid have been added. Pall Microfiltration System 31
After the solution is made and at the appropriate temperature, and minimum volume; the chemical solution is ready for use by either the EFM or CIP recipes. 1.4.2.2.2 CAUSTIC MAKE CYCLE This operator-started procedure makes up a batch of solution in the tank. The chemical makeup parameters are obtained from the currently loaded recipe. The Make Cycle is not a recipe step and is first manually initiated by the operators selection of the Tank graphic and then selecting CAUSTIC MAKE from the tank selection pop-up. After the first batch has been made by a manual initiation by the operator, the remake of the tank solutions can occur automatically if a recipe REFRESH step is run. If a REFRESH is triggered and the solution is already spent (too many washes), a full MAKE process is triggered instead of the limited REFRESH. The CAUSTIC MAKE sequence is as follows: The Caustic CIP/EFM Tank Water Supply Valve (V-5009) opens to fill the Caustic CIP/EFM Tank with potable water. The PLC will close the valve when the tank level reaches the recipe Caus Make Water Volume, as measured by Tank Level Transmitter (LIT-5006). While the tank is filling, the Tank Heater (H-5004) will be disabled until the tank level is above the Heater Enable Level setpoint. The heater will turn on when the tank temperature is below the H-5004 Temperature setpoint by more than the Temperature Deadband. The heater will turn off when the tank temperature is above the Temperature setpoint. While the Caustic CIP/EFM Tank (T-5001) is still filling but almost full of potable water, the PLC instructs the chlorine supply pump (P- 5402) to deliver the recipe Caus Make Dis Volume into the Caustic CIP Tank. Likewise, if the loaded recipe includes caustic solution, the recipe setpoint Caus Make Caus Volume is added via the caustic supply valve (V-5018) and the caustic supply pump (P-5015). It should be noted that the heater control is always active as long as the heater is in automatic mode if the level is high enough, the heater will always be trying to maintain the requested temperature, if in Auto. 32 PALL MICROFILTRATION SYSTEM
The Make sequence completes when all of the required water and caustic/chlorine have been added. After the solution is made and at the appropriate temperature and minimum volume, the chemical solution is ready for use by either the EFM or CIP recipes. 1.4.2.2.3 ACID TANK FLUSH The tank flush procedure is used to drain the tank and refill it with potable water. It is started by the operator pressing the FLUSH TANK button on the tank pop-up. The system reserves the Circulation area for use, ensuring that other processes cannot control equipment in those areas simultaneously. Acid Tank Outlet (V-5132), Circulation Pump Block (V-5282) and Drain Pump to Chemical Drain (V-5217) valves are opened to create a path from the Acid tank to the Chemical Drain via the circulation and drain pumps. Inappropriate valves are closed. Drain Pump P-5214 is run until Acid LL level switch (LSLL-5103) alarm or acid tank level (LIT-5106) drops below acid setpoint Tank Empty Level. The drain pump may stop and start multiple times in order to accomplish complete drain-out. The valve path closes and the Circulation area is released from reservation. The tank then fills with potable water via V-5109. The water fill stops when the water line rises to the programmed limit (LIT-5106 rises above the acid setpoint Acid Shutdown Level or LSHH- 5102 alarms). The flush volume is added as measured by LIT- 5106. The Flush process can do more than one flush (setpoint Number of Flush Cycles); if this is the final Fill cycle, the volume target is setpoint Final Flush Fill Volume; otherwise it is Tank Flush Fill Volume. If there is more than one flush cycle selected, the system counts flushes and loops back to repeat until they are all completed. Pall Microfiltration System 33
1.4.2.2.4 CAUSTIC TANK FLUSH The tank Flush procedure is used to drain the tank and refill it with potable water. If is started by the operator pressing the FLUSH TANK button on the tank pop-up. The system reserves the Circulation area for use, ensuring that other processes cannot control equipment in those areas simultaneously. Caustic Tank Outlet (V-5025), Circulation Pump Block (V-5282) and Drain Pump to Chemical Drain (V-5217) valves are opened to create a path from the Caustic tank to the Chemical Drain via the circulation and drain pumps. Inappropriate valves are closed. Drain Pump (P-5214) is run until Caustic LL Level Switch (LSLL- 5003) alarm or Caustic Tank Level (LIT-5006) drops below caustic setpoint Tank Empty Level. The drain pump may stop and start multiple times in order to accomplish complete drain-out. The valve path closes and the Circulation area is released from reservation. The tank fills with potable water via (V-5009). The water fill stops when the water line rises to the programmed limit (LIT-5006 rises above caustic setpoint Caustic Shutdown Level or LSHH-5002 alarms), or the flush volume is added as measured by (LIT-5006). The flush process can do more than one flush (setpoint Number of Flush Cycles); if this is the final Fill cycle, the volume target is setpoint Final Flush Fill Volume; otherwise it is Tank Flush Fill Volume. If there is more than one Flush cycle selected, the system counts flushes and loops back to repeat until they are all completed. 1.4.2.2.5 SOLUTION VALIDITY FUNCTIONALITY AND FORCE VALIDITY The control system monitors validity of solutions in the Acid and Caustic tanks and reports the status via the prompt displays. Validity is only checked if the chemical is actually used in the currently loaded recipe. Validity checking includes: Solution temperature within area setpoint 34 PALL MICROFILTRATION SYSTEM