Paper Machine Energy Considerations Dick Reese Dick Reese and Associates, Inc. Peachtree Corners, GA 770-448-8002 rareese@bellsouth.net
How to Conserve Energy
Energy Pop Quiz-1 1. On a typical paper machine, energy consumption is % higher than on top performing machines. 2. Energy consumption can usually be reduced by % without capital expenditures. 3. What operating changes provide good opportunities for reducing energy use without capital expenditures?
Energy Pop Quiz-2 3. What operating changes provide good opportunities i for reducing energy use without capital expenditures? a. Press section optimization b. Steam and condensate system operation c. Water heating d. Air handling systems e. Pulper operation f. Refining g. Steam box operation h. Trim optimization
Energy Pop Quiz-3 4. Which h paper grade requires the least energy use per ton? Fine Paper Linerboard Corrugating Medium Bleached Board Paperboard LWC Newsprint Tissue/Towel Kraft Paper Fluff Pulp Market Pulp
Energy Pop Quiz-4 5. What country in the world has the most fossil fuel reserves?
Energy Pop Quiz-4 5. What country has the most fossil fuel reserves? Answer-United States The U. S. has more oil in the ground than all of the Middle East put together. -Forbes Brothers According to Energy Department figures, almost 80% of potentially oil-rich offshore sites are off-limits to drilling; 60% of onshore sites are inaccessible as well Investors Business Daily 10/11/2010 New drilling techniques such as fracturing have greatly increased access to oil and natural gas.
Energy pricing and supply are a complicated political puzzle.
World Energy Demand is Increasing Energy demand is increasing rapidly in emerging market countries and exceeds 22 million barrels of oil per year. China, India, Russia, and the Middle East combined consumed more crude oil than the U. S. for the first time in 2008. International Energy Agency
Subsidy Dollars to Produce One MWh of Electricity EIA Energy Source Subsidy Dollars Refined Coal $29.81 Solar $24.34 Wind $23.37 Nuclear $1.59 Coal $0.44 Natural Gas $0.25
U. S. Steam Cost-$ per M lb
U. S. Electricity Cost- $ per MWh
Reducing Energy Operating Costs Papermaking is a complex process and each machine is unique. Improving energy efficiency requires careful evaluation of total paper machine operation. Significant energy savings can be realized on most paper machines by monitoring and benchmarking energy consumption and implementing cost effective changes.
How Can Opportunities to Reduce Energy Consumption on Paper Machines be Identified? The U. S. Department of Energy (DOE) funded development of a paper machine energy scorecard system. The scorecard system Uses Excel spreadsheets to ask comprehensive questions on paper machine components related to energy consumption. Compares each paper machine to energy performance on other machines producing similar grades.
Paper Machine Energy Scorecard System Scorecards are based on TAPPI technical information papers. 0404-63-Paper Machine Energy Conservation (developed from energy conservation tracks at TAPPI Papermaker conferences) 0404-47-Paper Machine Performance Guidelines Other TAPPI TIPs
TAPPI TIP 0404-63 (2011) Paper Machine Energy Conservation Five Basic Principles 1. Minimize amount of water evaporated in the dryers. 2. Minimize amount of steam condensed outside the dryers. 3. Maximize condensate return flow and pressure to the power house. 4. Minimize electrical consumption for key users. 5. Monitor and manage energy consumption and cost.
Paper Machine Energy Scorecard System Improves awareness of paper machine energy consumption Helps identify opportunities to reduce energy consumption and cost Provides comparison to energy best practices
Paper Machine Energy Scorecard Worksheets Paper machine basic data Grade specific information Paper machine energy monitoring Dryer section Press section Auxiliary systems including refining, vacuum application, water systems, stock agitators t and pumps, steam showers, CD profile control, o and machine room ventilation Summary
Grade Specific Energy Scorecard Worksheets Linerboard Corrugating medium Fine paper Bleached board Kraft paper Recycled Paperboard Newsprint LWC Market pulp Fluff pulp
2008 - Dick Reese & Associates Inc. GRADE ENERGY SCORECARD Why Important Comparison of energy performance to other paper machines producing the same grade is a good way to benchmark energy consumption. What is the major grade produced? Paperboard ACTIONS YOUR SCORE COMMENTS 4,201-5,000 G4 What is total steam consumption on the paper machine 10 4,295 lb/gross ton)? >400 G5 What is electrical consumption (kwh/gross ton)? 0 346 Gas=0.37 MMBtu/t >7.0 70 G6 What is total energy consumption (MMBtu/gross ton)? 0 7.8 1,501-2,000 G7 What is total water consumption (gal/gross ton)? 10 1,742
PAPER MACHINE ENERGY SCORECARD 28/Sep/10 COMPANY NAME ABC Paper MILL LOCATION Great Place, CA, USA PAPER MACHINE NUMBER 1 SUMMARY RESULTS 2008 - Dick Reese & Associates Inc. POSSIBLE YOUR PERCENT PAPER MACHINE ENERGY QUESTIONS SCORE SCORE ENERGY MONITORING 200 200 100% DRYER SECTION-CYLINDER DRYERS 340 205 60% PRESS SECTION 285 62 22% AUXILARY SYSTEMS A. REFINING 165 123 75% B. VACUUM APPLICATION 145 60 41% C. WATER SYSTEMS 160 133 83% D. STOCK PREPARATION AND PUMPS 100 40 40% E. STEAM SHOWERS 40 30 75% F. CD PROFILE CONTROL 30 15 50% G. MACHINE ROOM VENTILATION 90 55 61% GRADE SCORECARD 305 90 30% Grade Selected Paperboard TOTAL SCORE 1,860 1,013 54%
Scorecard Summary Scorecard (Number of Questions) Possible Your Percent of Score Score Potential ti Grade (14) 170 85 50 Energy Monitoring (19) 155 75 48 Dryer Section (24) 190 135 71 Press Section (18) 180 150 83 Refining (13) 90 64 71 Vacuum Systems (11) 95 80 84 Water Systems (12) 130 67 52 Agitators and Pumps (7) 10 6 60 Steam Showers (7) 40 25 63 CD Profile Control (3) 30 23 77 Machine Room Ventilation (8) 50 25 50
Paper Machine Energy Evaluation Observations Indices Units Low Observed High Observed Good Performance Fiber Loss % Production 0.04 2.0 <0.1/<0.5 Cleaner Diameter in 3 12 <9 Vacuum Pumps model Nash # Blowers Modern Designs Press Shower Temp o F 43 150 Sheet Temp. or Higher Trim Loss % 1.0 10.0 <2 Wet End Dryer Control None Low DP- Stationary Syphons Low DP- Stationary Syphons Reel Moisture % 3.6 10.5 Varies By Grade Moisture to Size Pr % 0.7? 5.0 30 3.0 Starch Solids % 4.5 19 8/13 Condensate Return %? 90+ 75-80
Paper Machine Energy Evaluation Observations Indices Units Low Observed High Observed Good Performance Steam Use lb/gross t 2,121 17,300 2,000-5,000 Electricity Use kwh/gross t 133 1,132 150-500 Total Energy Use MMBtu/gross t 4.6 12.4 4.0-7.0 Water Use gal/gross t 129 25,520520 500-2,000 000 Whitewater Temp. o F 95 165 <120-130 Couch Solids % 15 30 21-30 Press Solids % 26 54 42-51 PV Temperature o F 150 270 <180 Drying Steam lb steam/lb 1.2 1.5 <1.3 H 2 O evap
Liner and Medium Energy Performance Targets TAPPI TIP 0404-63-2011 Corrugating Index Units Liner Medium Uptime % 94 94 First quality % 97 97 Overall machine efficiency % 91 91 Total steam consumption lb/ton 2,800 2,750 kg/tonne 1,400 1,400 Electrical consumption kwh/ton 300 300 kwh/tonne 330 330 Total energy cons. MMBtu/ton 5.0 5.0 GJ/tonne 5.8 5.8 Water consumption gal/ton 1,500 1,500 m3/ton 5.7 5.7 Couch solids % 27 27 Press solids % 42/50 42/50 Size press moisture % NA NA Reel moisture % 7.5 10.5 Drying steam lb steam/lb water evap 1.2 1.2 PV supply temperature F <180 <180 C <80 <80 Condensate return % 75-80 75-80
Relevant Quotation Do what you can with what you have, where you are. Teddy Roosevelt, 26 th President of US
What Are the Ultimate Low Hanging Fruits?
Energy Reduction Opportunities Implementation Total Payback Cost Range Savings Period $ ($/year) Range (years) 1 Shut off steam to bottom unrun dryers 1,000 190,000 0.01 2,000 001 0.01 2 Reduce VA supply air temperature 1,000 37,000 0.03 2,000 0.05 3 Increase press shower water temperatures 10,000000 148,000 007 0.07 20,000 0.14 4Increase second main press loads 10,000 148,000 0.07 20,000000 014 0.14 5 Change to 480 volt Install VFD on boiler feedwater pump 100,000 96,000 1.04 130,000 1.35 6 Install new trim air compressor with VFD and control system 200,000000 96,000 208 2.08 240,000 2.50 Total 619,000
Top Areas for Energy Reduction Water Systems Steam and Condensate Systems Pressing Pumps Heat Recovery e Slowed Back Production Rates Pulpers and Agitators Refining Steam Boxes Vacuum Systems Size Press and Coaters