aumann

Energy-Efficient Kiln for BrickmakingSeptember 17, 2003 : Energy-Efficient Kiln for Brickmaking September 17, 2003 Donald J. Aumann, PE PIER Buildings Program


Introduction : Introduction Presenting on behalf of Clint Lowell from Energy Commission Efficiency Division Don did the report in 1999 while working as a consultant …coincidence that I joined CEC CEC project connection from administering US Department of Energy funds No new information since 1999 report


Outline : Outline Background Old kiln technology New kiln technology Startup issues Results—business and technical


Background : Background Pacific Clay Plant Located about 100 km east of Los Angeles Existing since late 1800s Extensive production of bricks, pavers, & pots


Background : Background Used 1950s vintage kilns Increased product demand in early 1990s …need to increase production capacity


Old Kiln Technology : Old Kiln Technology Large mass of bricks on each kiln car (2 meters high) High-refractory kiln cars Relatively low heat transfer rate


Search for New Kiln : Search for New Kiln International search Pick US technology from Swindell Dressler (www.swindelldressler.com) Pacific Clay was 2nd installation (1st was in Australia)


Initial Project Cost : Initial Project Cost


Project Schedule : Project Schedule Activity Planned Actual . Begin design July 1995 July 1995 Construction complete Sept. 1996 April 1996 Extend TK-4 none Dec. 1996 Proper TK-4 operation Jan. 1997 Dec 1996


Construction/Start-Up Issues : Construction/Start-Up Issues County zoning/regulations change …Raise plant 0.6 meters …Improve fire protection …Increased cost $0.5 million to $7.8 million 35% initial production loss rate …Expected 1–2% loss rate …Cool-down zone too short …Extend kiln 7 meters  immediately achieve 1–2% loss rate


Start-Up Labor Issues : Start-Up Labor Issues New production line is more sophisticated/automated …4-hour backlog requires continuous operation (old kilns had 2.6 day backlog) …Continuous full-staffing required …Continuous supervision required Labor summary …Old plant required two low-skilled crews …New plant requires four high-skilled crews


Technical Performance : Technical Performance Characteristic Old New Improvement Production capacity (tons/year) 30,000 60,000 100% Burner rating (106 Btu/hr) 29 25.9 Na Production loss (%) 10 5 50% Firing plus drying time (hours) 96 48 50% Exact duration depends on product requirements, with approximately 50% of the time for drying. Preheat time (cold start, hours) 96 24 75%


Energy/Emissions : Energy/Emissions Characteristic Old New Improvement Natural gas use (therms/ton) 67.3 43.6 35% Electricity use (kWh/lb brick) 0.0426 0.0448 -5% NOx emissions (lb/106 Btu gas) 0.056 0.062 -11% lb./ton brick 0.377 0.270 28% (NOx for “oxidizing” firing)


Operating Cost Comparison : Operating Cost Comparison Cost Component Pre-TK-4 Post TK-4 Savings $/ton $/ton Gas Cost 17.51 11.34 35.2% Electricity Cost 7.76 8.17 -5.3% Labor Cost 12.81 14.03 -9.5% Maintenance Cost 13.02 9.61 26.2% Total 51.10 43.15 15.6%


Suggestions for Future Plants : Suggestions for Future Plants Adopt Different Production Layout Use more kiln cars Include increased kiln car storage Provide 2-day backlog Lower labor costs from using only two crews


Summary : Summary Vice President Allen Cunningham “Installing this new kiln is like having children…when you’re done, you’re glad you did it.” “Yes, we’d do it again!”