Di ti agnos cs & O ti p i m t za ittion of of Pollution Control Systems y Dan Bemi MEGTEC Systems I nc Inc.

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1 Diagnostics & Optimization i of Pollution Control Systems Dan Bemi MEGTEC Systems Inc.

2 Oxidizer Functionality Concerns Process safety Directly effects fuel usage, both at the oxidizer and process Compliance with EPA laws Process uptime Possible production increases if oxidizer is optimized

3 Process Safety Concerns Safety interlocks not operating properlyp System does not shutdown during a critical fault Employee safety concern Equipment damage Fire and building damage Loss of production Fuel train safeties not functioning or improperly p set Settings changed or bypassed over time Insufficient air flow from the process Explosive l i atmosphere at the process OSHA employee exposure limits NFPA safe ventilation for solvents NFPA 86 Chapter 10

4 Energy Usage Improperly tuned gas train/burner Too much combustion air causes increased gas usage Too little combustion air causes gas to be burned inefficiently (you pay for the unburned gas) Masked/poisoned catalyst Oxidizer has to operate at higher than normal temperature to achieve destruction Leaking ggaskets and dampers and ductwork Increased air flow to the oxidizer that needs to be heated Plugged filters and heat exchangers Increased c pressure e drop Decreased air flow Increases electrical usage Over exhausting process Increased gas usage at the oxidizer Increased gas usage at the dryer

5 EPA Compliance Improperly tuned gas train/burner Increased CO and NOX production Masked/poisoned catalyst Decreased VOC destruction Leaking gaskets and dampers Leaks VOC to atmosphere Plugged filters and heat exchangers Increased d air emissions i due to additional electricity (CO2) being consumed Plugging can result in HX failures

6 Process Uptime Oxidizer continues to fault due to mechanical and wiring issues Process continually having to shutdown Insufficient air being removed from the oven Oven faults on low airflow Waiting for the oxidizer to purge and heat-up Time to get the process running well over and over Possible failed test resulting in production Possible failed test, resulting in production downtime and EPA fines

7 Production Increases Correct airflow from the process Process speed can be increased Leaking dampers and ductwork can cause less airflow from the process Replace gaskets and filters Oven and oxidizer efficiency increases allowing for increased process speed Fix insulation leaks that cause radiant heat loss No lost time due to oxidizer/process down time

8 Managing Oxidizer Performance Often Used Methodology: Just change operating parameters to compensate for equipment deficiencies. Correct Methodology : Process/oxidizer tune-up for optimization Initiate a Preventive Maintenance plan OEM should be considered Clean air filters & screens Replace gasketing on doors Adjust air supply & exhaust balancing dampers Have burners maintained and tuned Use only as much air/heat as needed Fan balancing and belts Future : Establish a baseline Document current operating parameters Measure and record flows and energy usage Determines whether improvements are being made What is the next step?

9 Dryer / Oven Energy Reduction Dryer air re-circulation to replace once-thru pass air path with re-circulating air handling system. Direct a portion of exhaust back to supply Installation of LEL monitors / controls Exhaust flow reductions of 50% to 65% are common Dryer exhaust air cascading Used on multi zone process dryers Direct dilute exhaust stream to make up air of earlier zones Total enclosures if used as make-up-air

10 Oxidizer Diagnostics What is in the Catalytic Oxidizer Diagnostic Toolkit?

11 Oxidizer Diagnostics What is in the RTO Diagnostic Tool Kit?

12 Oxidizer Diagnostics Temperatures & Pressures Record and compare Both on screen and by hand Keep records Flows Individual process & total Don t forget the combustion air Faults and alarms If they re-occur it could mean something more serious Are they increasing What are the faults Physical inspection Structural damage Leaking dampers or doors Hot spots or insulation damage OEM can monitor these things for you Many can be monitored over modem or VPN connections

13 Catalytic Oxidizer Diagnostics Annual catalyst activity testing Test at multiple temperatures Keep records Compare graphs Look for sudden drops in performance Temperature rise across catalyst Record products being run or LFL readings 1% LFL = approximately 25 degrees rise Pressure profile Possible plugging indicator Can cause increased energy usage Could lead to under exhausting the oven Burner operation Visually check the flame Is it even? What is the color?

14 RTO Diagnostics Heat recovery bed inspection Particulate on top of bed Particulate under cold face Structural supports Look for signs of plugging Pressure profile High pressure drop across beds could mean plugging Can cause high energy use Bed temperature profile Multiple thermocouples is important Monitor and record over time Look for sudden changes High outlet temperature on one bed Can be an indicator of problems Consult the OEM if this persists Proof Of Flow Switch Differential Pressure Transmitter Combustion Blower Pressure Switch Seal lair Pressure Switch Drip Legs

15 Alarms/Faults Tell a Story What is your oxidizer trying to tell you? My components are failing I m not being operated correctly You are giving me the improper amount of air I could be operated more efficiently Fix me soon or I will shut you down What do you do with your car when warning lights go on? Try to check it out yourself - maybe Bring it in for service - maybe One of the above definitely if you want it to last Many alarms can be evaluated via modem or VPN monitoring Annual OEM Preventative Maintenance is recommended

16 How can your OEM assist? Equipment that is easy to diagnose Does the equipment have the necessary instrumentation t ti Do the faults/alarms align with the actual problem Set-up maintenance program Recommend inspections and diagnostics On-line modem/vpn support Qualified people that can work on the oxidizer over the modem Can record data over time Knowledgeable service and engineering personnel Assist in record keeping Trouble shoot faults/alarms and other sudden changes in the system Catalyst testing services Annual preventative maintenance On-site oxidizer inspections Help fill in your records

17 Diagnostics : Cat-Ox Case Study Problem: Oxidizer struggling to maintain ready temperature Diagnostic Trail Customer noted huge increase in gas usage and that they were experiencing loss of ready temp signal Suspected over-exhausting of process dryer Measured oxidizer inlet and outlet flows and found 30% greater outlet flow (note: point of measurement was prior to hot air recirculation loop) Inspected high h temperature t recirculation loop The Solution Investigation of high temperature recirculation loop revealed that the photohelic sensor had failed, forcing the fresh air damper to be driven to a full open position resulting in an additional 30% excess cold air intake at the inlet to the oxidizer fan high-temperature

18 Diagnostics : Cat-Ox Case Study Problem: Combustion Chamber (Low Temperature Fault) Diagnostic Trail Verify that the thermocouples are reading accurately Verify that gas train components are assembled and functioning correctly Verify gas pressure stability If all check out then consider control adjustments The Solution The PID parameters controlling the gas valve operation had been altered, causing the gas valve control to be sluggish and slow to respond to process changes A comparison to original set up data would have identified a change in the control scheme

19 Diagnostics : RTO Case Study Problem: RTO would not stay in self sustain mode during high solvent loading conditions Diagnostic Trail Verify thermocouple accuracy in combustion chamber Verify solvent concentrations are adequate for predicted self-sustained operation by referencing dryer LEL monitoring devices Verify PLC burner control set points Review media bed temperature profiles The Solution Bed temperature profiles confirmed that solvent combustion was taking place very low in the media beds allowing the air to transfer heat back into the media before entering the combustion chamber. The bed profile temperatures also indicated that the oxidizer was achieving a very high thermal efficiency, and therefore, the hot-side bypass set-point could be adjusted. By adjusting the set-point, more air was bypassed directly to the stack. The higher bypass flow successfully forced the solvents to burn higher up in the media beds, thereby maintaining the required combustion chamber set points. This resulted in the expected self-sustained oxidizer operation.

20 Diagnostics : RTO Case Study Problem: High Duct Negative Pressure Fault Diagnostic Trail Verify proper operation of oxidizer exhaust fan VFD Verify that the duct negative pressure transmitter that controls fan speed is functioning properly Verify that PID loops are set and functioning properly Check process exhaust fan and T-damper function The Solution In this case, the process T-dampers were pneumatically actuated. A flow control speed adjusting valve had been opened fully which allowed the damper to transition to atmosphere too quickly. The RTO exhaust fan could not be slowed down fast enough to account for the abrupt loss of air flow resulting in high duct suction pressure

21 Improve Catalytic Oxidizers Efficiency Many retrofits are available to improve efficiency Burner retrofits to improve temperature distribution Use of process air for combustion air Better controls & process interface Variable speed drives to control flow Catalyst replacement Economizer

22 RTO Energy Upgrades Improved ceramic heat recovery media available. Structured ceramic media Provides higher heat recovery Reduce system pressure drop (horse power) Can increase system flow capacity by 10+% Improved temperature control systems. Air/fuel ratio control RTO to RCO Conversion - Catalyst Retrofit 50%+ Operating cost savings are predicted Better process interface systems Isolate process when not in use

23 Secondary Heat Recovery Options Secondary heat recovery systems are used to recover excess energy in the exhaust stream of processes or oxidizers. This should only be addressed after the process, oven, and oxidizer systems have been optimized. Capture systems, oven re-circulation and oxidizer optimization should be completed first. This requires significant knowledge of the process System optimization requires a commitment from the user in defining the process. Biggest challenge is finding a user for the energy OEM can provide help in this area

24 Benefits of Optimization: Case Studies 1. Over exhausting process due to oven re-circulation system being set improperly 2. Energy savings benefit of not exhausting ovens when product is not being run 3. Not oxidizing air from a water based product oven 4. Catalyst Replacement 5. Catalytic Economizer

25 Oven Exhaust Re-circulation Case 1 Oven exhaust balancing system was set to only re- circulate 10% of the exhaust flow An evaluation showed that it could be set to 50% This decreased the air flow to the oxidizer by 3,200 SCFM Savings at the oven was 660,000 BTU/HR Savings at the oxidizer was 630,000 BTU/HR Total Savings 1.29 MM BTU/HR ($86,688 savings annually)

26 Increase Exhaust Re-circulation Case 1 Fresh air (make-up 2,000 scfm 4,000 scfm 4,000 scfm to oxidizer VOC input at 1 lb./min. Dryer 8,000 scfm Dryer Exhaust Web 1,000 scfm 1,000 scfm

27 Oven Exhausts to RTO when No Product is Running Case 2 Evaluation showed oven exhaust fan was running with no product in the oven This was the case for 30% of the time The air sent to and heated by the oxidizer was 6000 SCFM The building MUA was also heating this air from ambient Combination savings at the oxidizer & MUA assuming full time operation was 1,188,000 BTU/HR $26,950 saved annually assuming operating case represented 30% of total operating hours

28 Oxidizing Air from Water-based Product Case 3 Customer was oxidizing air from a water based product. The permit showed that it did not need to be oxidized. This product was run 75% of the time on this line. The additional airflow to the oxidizer was 10,000 SCFM. Savings at the oxidizer was 1,650,000 BTU/HR $88,350 saved annually

29 Catalyst Replacement Case 4 Customer had increased operating temperature to 700 degrees F to meet the VOC destruction permit Old catalyst was severely masked with silicone Assisted customer in locating source of silicone which was then eliminated Retrofitted new catalyst and the operating temperature was dropped to 550 degrees F Oxidizer size was 15,000 SCFM $166,320 saved annually

30 Catalytic Oxidizer Economizer Case 5 Customer was interested in recovering heat from his oxidizer (in order to reduce operating costs) Needed to find a Btu load that would use the heat 24/7 Determined that the oxidizer itself was the best option Also used some of the heat for the maintenance shop and ink storage Worked with the customer to keep the cost down and keep the project within a predicted 1.5 year payback Saved half of the annual gas used at the oxidizer plus additional building heat Annual savings was roughly $180,000 year and project came in under a 1 year payback

31 Catalytic Oxidizer Economizer Case 5

32 Summary Using diagnostics and optimizing your oxidation system can save you money Good maintenance and housekeeping help systems operate more safely and efficiently. Both equipment efficiency upgrades and replacement with higher efficiency equipment should be considered OEM s can provide engineering evaluations of your existing equipment. Consider add-on heat recovery equipment There is funding available in some areas of the country for efficiency upgrades.

33 Financial Assistance Many states have programs for partial funding, tax incentives or low-cost loans. Visit to see what may be available in your area. DOE (Department Of Energy) offers funding for energy reduction feasibility studies. Vendor may offer terms aligned with payback period.

34 THANK YOU! Dan Bemi MEGTEC Systems Inc.