Increasing Energy Efficiency in the Web Coating Process

Transcription

1 Increasing Energy Efficiency in the Web Coating Process By Ed Cohen Edward Coating Consulting & Dan Bemi MEGTEC Systems, Inc.

2 Fossil Fuel Dependency 2

3 How to Keep Your Competitive Edge Know what energy you consume Keep good records Consider monitoring equipment (gas meters) Know where process energy is being consumed Measure and analyze Modify process to be more efficient Start with procedures Then move to equipment 3

4 Why Focus on Energy Efficiency? Energy cost contribution to total production cost is usually fairly low (NAM Study indicates between 2-5% over a broad range of manufacturing) Therefore, energy savings opportunities are often overlooked when companies conceive and implement cost savings programs This is a serious mistake for many reasons! 4

5 Why Focus on Energy Efficiency? 1. Average manufacturer can save between % of total production energy consumed As much as 30% of these saving can come without any capital expenditures 2. Resource conservation efforts often yield very high returns on investment Frito Lay efforts routinely earn 30% ROI DuPont claims over 75 Six Sigma projects with $250,000 savings/project Statistics per NAM Report Efficiency and Innovation in U.S. Manufacturing Energy Use 5

6 Why Focus on Energy Efficiency? 3. Energy efficiency projects often produce significant secondary benefits Waste reduction, increased throughput, quality improvements, more uptime 4. Intangible, but marketable, value-added benefits Greener image, Smaller carbon footprint, Sustainable processor, Lean manufacturer, Culture of continuous improvement 6

7 Why Focus on Energy Efficiency? 5. Emerging new business development opportunities Green, Sustainable, Environmentally Friendly products are increasingly in demand 6. Potential for reduced costs of compliance and Government sponsored energy subsidies Reduced fuel usage means reduced emissions Federal and State programs are available to assist with identification and implementation of energy savings projects 7

8 Where to Start? Conduct a process energy audit Can usually be handled in-house by the plant engineering and maintenance staff Consultants and/or state government expertise offered under the umbrella of the Department of Energy Industrial Technology Program Identify the main energy users in the process and then measure or estimate energy consumed under light, normal and maximum operating conditions 8

9 Typical Coater/Laminator Line DRYER INFEED PULL ROLL COATIN G GAUGE DRYER EXIT WEB GUIDE 9 6 [ MM] OPERATOR PLATFORM COATING STATION WEB INFEED GAUGE PULL ROLL AND CORONA TREATER OPERATOR PLATFORM PRIMARY UNWIN D PRODUCT WINDER DAN CER UN IT COOLING PULL ROLLS LAMINATOR AUXILIARY UN WIND 9

10 Sample Process Operating Conditions Line Speed: Substrate: Web Width: Dry Coat Weight: Solids Content: 1000 FPM 4 mil PET 60 inches 10 GSM 50% for Water-based Case 25% for Solvent-based Case 100% for Hot Melt Case 10

11 Evaluating Process Energy Usage Pareto Chart Analyses Used to Identify Low Hanging Fruit Case 1 - Pareto Chart Water-Based Convection Air Drying Case 1A - Pareto Chart Water-Based Convection Air Drying with IR Preheater Series Dryer Dryer Fans Product Winder Corona Treater Primary Unwind Auxiliary Unwind Laminator Coating Station Infeed Pull Rolls Dryer Infeed Pull Roll Laminator Pull Rolls Cooling Rolls Dryer IR Heater Dryer Fans Product Winder Corona Treater Primary Unwind Auxiliary Unwind Laminator Coating Station Infeed Pull Rolls Dryer Infeed Pull Roll Laminator Pull Rolls Cooling Rolls Coating Line Components Coating Line Components Series1 Kw Kw

12 Evaluating Process Energy Usage Pareto Chart Analysis Used to Identify Low Hanging Fruit Case 2 - Pareto Chart Solvent-Based Convection Air Drying Series1 12 Kw Dryer Dryer Fans Product Winder Corona Treater Primary Unwind Auxiliary Unwind Laminator Coating Station Infeed Pull Rolls Dryer Infeed Pull Roll Laminator Pull Rolls Cooling Rolls Coater Line Component

13 Value-Stream Mapping Break down the process into finite elements that either contribute, or not, to end-product value Drying Process Heat Set Printing Example 1. Web conveyance function 2. Solvent evaporation function 6.0% Heat Load 3. Web heating function 4. Safe operating function 22.1% 1.8% 13.5% 56.6% Paper Exhaust Air Water Solvent Radiation 5. Exhaust air heating function 6. Radiation heating function. 13

14 Pick the Low Hanging Fruit First According to Department of Energy Statistics, energy system integration and best practices opportunities, along with waste heat and energy recovery systems, account for more than 60% of the top R&D opportunities for energy savings 14

15 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Seal dryer leaks Low Cost Investment Opportunities Re-insulate hot spots Adjust flow balancing dampers Maintain heat sources Align idler rolls and maintain bearings Review and improve SOPs Turn off those dryers during long changeovers and make-ready operations 15

16 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Low Cost Investment Opportunities Model your processing requirements so as to match thermal resources to product output (recipe management) Recipe driven damper adjustment Recipe driven temperature adjustment Remember that efficiency is a measure of energy input per unit of production output so don t be afraid to dial up temperature if it results in throughput improvement 16

17 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Moderate Cost Investment Opportunities Automating air flow control dampers Adding exhaust recirculation loops Adding web IR sensors to control burner output Install data collection equipment (meters and monitoring) Energy saving maintenance and standard operating procedures can be implemented Sometimes it is as simple as knowing when to bring processes on and off-line Remember process energy is often directly linked to plant energy usage (MUA unit operation, doors left open etc.) 17

18 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Technology-Based Investment Opportunities For waterbased processes dryer exhaust heat can be recuperated using a heat exchanger Cool Exhaust Air to Atmosphere Hot Dryer Exhaust Air Flow Preheated Dryer MUA 18

19 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Technology-Based Investment Opportunities Exhaust air flow from water-based processes can be reduced by installing humidity control monitoring equipment Coated Web Out Humidity Monitor Recirculation Manual Balancing Dampers Exhaust Damper Make-Up Air Damper Make-Up Air Exhaust Fan Burner Exhaust To Atmosphere Manual Balancing Dampers Supply Fan Coated Web In 19

20 Drying Process Efficiency Improvements Reducing heat loss and exhaust flow Technology-Based Investment Opportunities Exhaust air flow from solvent-based processes can be reduced by installing LEL monitoring and/or control equipment Coated Web Out LFL Monitor LFL Monitor (Redundant) Safety Interlock Recirculation Manual Balancing Dampers Exhaust Damper Make-Up Air Damper Make-Up Air Exhaust Fan Burner Exhaust To Atmosphere Manual Balancing Dampers Supply Fan Coated Web In 20

21 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities This schematic shows a direct heat recovery system mixing hot RTO combustion chamber air with fresh outside air and returning the blended airstream to the process dryers. 21

22 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities Clean air exhausted from oxidation equipment used in many solvent-based processes can be tapped for energy using an air-to-air heat exchanger 22

23 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities Skid-mounted, air-to-air heat exchanger systems are available as add-on devices. 23

24 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities This schematic shows an addon, water-glycol heat recovery loop being used to preheat boiler feed water. 24

25 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities This schematic shows an addon, water-glycol heat recovery loop being used to preheat the process exhaust stream to the oxidizer and to provide building MUA air heat 25

26 Drying Process Efficiency Improvements Heat Recovery Schemes Technology-Based Investment Opportunities This schematic shows an RTO equipped with thermal oil heat recovery. Process dryers feature thermal oil heat sources for a fully integrated, energy efficient system. 26

27 Other Process Efficiency Improvements Formulation related energy savings Process Chemistry Opportunities Isoproponal Drying Load Increasing the coating solution concentration can significantly reduce dryer heat loads. 27

28 Other Process Efficiency Improvements Formulation related energy savings Process Chemistry Opportunities Increasing the coating solution concentration can also reduce mixing energy requirements. 28

29 Other Process Efficiency Improvements Formulation related energy savings Process Chemistry Opportunities Where technically feasible, consider using easier drying solvents with slightly higher vapor pressure and lower heat of evaporation rates in order to speed up the drying process Heat of Evaporation Solvent Btu/lb Acetone 173 Toluene 151 MEK 186 Isoproponal 335 Water

30 Other Process Efficiency Improvements Formulation related energy savings Process Chemistry Opportunities Increasing solids concentrations can also save energy by reducing both the time and temperature required for good mixing 30

31 Other Process Efficiency Improvements Consider Changing Your Process Process Substitution Opportunities Depending on end product performance requirements, the use of solvent, and the need for thermal drying can be eliminated by using a 100% solids, hot melt, process. Kw Case 1 - Waterbased Energy Comparison Chart Case 1A - Waterbased with IR Assist Case2 - Solventbased Coating Process Type Case3 - Hot Melt Series1 31

32 Other Energy Considerations Alternative & Renewable Energy Converting Industry Focus Reducing energy costs Reducing carbon footprints Insuring uninterrupted availability of energy Electrical Cogeneration (Heat recovery, water generators) Local energy resources (wind, water, landfills, geothermal) Creativity and cooperation will be keywords for converting industry energy management as they plan for the future Mohawk Fine Paper 60% of all electricity from wind-power Fujifilm Landfill methane recovery 32

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 33

34 Summary Energy costs will continue to rise Taking a total energy management approach will make you more competitive and profitable Look to best practices and technology as sources for energy efficiency improvements Energy efficiency projects often lead to product and process quality improvements that go well beyond mere cost savings Renewable energy sources will be an important part of our energy future and it is not too early to start investigating their role in your process Research potential for financial incentives 34

35 MEGTEC Systems & Edward Coating Consulting Thank You 35