Heat treatment of mills and storage structures 4 th Annual IAOM Southeast Asia District Conference & Expo 8-1 October 213 Ho Chi Minh City, Vietnam Dr. Raj Hulasare, Scientist, Temp Air, Inc; Burnsville, MN Dr. Bhadriraju Subramanyam: Dept. of Grain Sci. & Industry, KSU, Manhattan, KS
Heat Treatment Historical Look 1762, France: 69 o C / 156 o F for 3 d, moth 186, England: 57 o C / 135 o F for grain 191, USA: heat treatment of mills 192, USA: 3 mills use heat in OH, PA 1932, France: MB as insecticide Used first 251 yrs ago!
History of Heat Treatments 195 s: Quaker Oats using heat 1983: EDB banned 199 s: increased interest in heat 1992: MB found ozone unfriendly 1994: Dursban in Cheerios 25: MB to be phased out 26: MB extension US, Canada??? Source: P. Fields, AAFC, Canada
Drivers - Heat Treatment (HT)? HT Consumer Preference Eco-Friendly Technology Insect Resistance Pesticide-free Products Montreal Protocol US Clean Air Act Higher dosage, Time, Life stages? Green IPM
Heat Advantages Safe: non-chemical, people-safe Effective: kills all life stages Eco-friendly: E no ozone depletion, toxic fumes, or corrosive effect Heat treat: Facilities, Bins & Silos
Heat Advantages SEE Safe Effective Eco-friendly No evacuation of personnel No Sealing (except doorways, loading docks etc.) Spot Treatments continued productivity within plant, offices, warehouse etc.
Temperature ( C) Temperature ( F) Temperature Effects on Insects 7 Targeted temp. spectrum 12 14 F (5-6 C) 6 5 14 12 4 3 2 1-1 -2-3 1 8 6 4 2-2 Source: P. Fields, AAFC, Canada
Heat treatment concept: Raising the ambient air temperature of the complete facility, or a part of it, to 122-14 o F (5-6 o C), and maintaining these temperatures for at least 24 hours Gas heaters Electric heater Steam heater Duct carrying heat from gas heaters Fan
Efficacy to Control Pests MBr Methyl bromide PH 3 - Phosphine SF (Profume) CO 2 Carbon dioxide O 3 - Ozone..... Efficacy function of temperature
Heat Treatment Insects lethal threshold temperatures High Temperature [12-14 F/(5-6 C)] HT Process Ambient temperature Low Humidity ( 25%) (Desiccation/Dehydration)
Heat Vs MB - Downtime Comparison (hours) Methyl Bromide Sealing... Set up...4-6 Fumigation...24 Aeration...12-24 TOTAL 4-54 Plant evacuation mandatory Thermal Remediation Set up.. Heat up. 6-8 Kill Period. 24 Cool down...2-4 Tear down.1-2 TOTAL. 33-4 Untreated areas operational
Positive Pressurization Forced ambient air (Patented Process) US & Canadian Patents Positive pressure Good air distribution Hot air is pushed into corners, cracks and crevices Calculated and controlled infiltration Lower relative humidity
Re-circulating Inside Air Negative pressure Poor air circulation Uncontrolled infiltration No air changes Low temperature zones (cold spots)
Construction Heat Principles: Make-Up vs. Recirculating Recirculating heaters promote thermal stratification and infiltration Make-up air heaters provide uniform temperatures, pressurize the structure, and exhaust moisture and fumes
Steps in Heat Treatment Setup, HT, Document & Review Equipment mobilization
Real-time Wireless Temperature Monitoring Untreated Area (Office) Receiver Heater Heater Heater Treated Area Temperature transmitters
Effective Heat Treatment Manage airflow for Uniform Temperature Profile HOT Pockets COLD Monitor Temperatures throughout heated area Real-time adjustment Real-time Wireless Temperature Monitoring System Documentation for QC Worker Safety & Savings
Temperature ( F) 16 14 12 1 8 6 4 2 Start of the Heat Treatment (6 C) (49 C) (38 C) (27 C) Tx:49 sensor in office on 3rd floor Tx:49 sensor in office on 5th floor /16, 6:14 9/16, 8:38 9/16, 11:2 9/16, 13:26 9/16, 15:5 9/16, 18:14 9/16, 2:38 Date and time 9/16, 6:14 9/16, 8:38 9/16, 11:2 9/16, 13:26 9/16, 15:5 9/16, 18:14 9/16, 2:38 Fig. 1: Realtime Temperature Profile from Sep 16, 26, 6:35 AM to 9:5 PM Fig. 1: Real-time Temperature Profile Tx: 27 Tx: 28 Tx: 29 Tx: 3 Tx: 33 Tx: 34 Tx: 35 Tx: 36 Tx: 37 Tx: 38 Tx: 39 Tx: 4 Tx: 41 Tx: 42 Tx: 43 Tx: 44 Tx: 45 Tx: 46 Tx: 47 Tx: 48 Tx: 49 Tx: 5 Tx: 51 Tx: 52 Tx: 53 Tx: 54 Tx: 55 Tx: 56 Tx: 57 Tx: 58 Tx: 59 Tx: 62 Tx: 64 Tx: 65 Tx: 66 Tx: 67 Tx: 68 Tx: 69 Tx: 7 Tx: 75 Tx: 76 Tx: 77 Tx: 78 Tx: 79 Tx: 8 Tx: 81 Tx: 82 Tx: 47 Tx: 48 Tx: 49 Tx: 5 Tx: 51 Tx: 52 Tx: 53 Tx: 54 Tx: 55 Tx: 56
Temperature ( F) Temperature ( F) 16 16 14 14 12 12 1 1 8 8 6 End of the Heat Treatment (6 C) (49 C) (38 C) (27 C) Tx:49 sensor in office on 5th floor Tx:49 sensor in office on 3rd floor 6 4 4 2 2 9/16, 6:14 9/16, 8:38 9/16, 11:2 9/16, 13:26 9/16, 15:5 9/16, 18:14 9/16, 2:38 Date and time 9/16, 2:24 9/16, 22:48 9/17, 1:12 9/17, 3:36 9/17, 6: 9/17, 8:24 9/17, 1:48 9/17, 13:12 Fig. 1: Realtime Temperature Profile from Sep 16, 26, 6:35 AM to 9:5 PM Fig. 2: Real-time Temperature Profile Tx: 27 Tx: 28 Tx: 29 Tx: 3 Tx: 33 Tx: 34 Tx: 35 Tx: 36 Tx: 37 Tx: 38 Tx: 39 Tx: 4 Tx: 41 Tx: 42 Tx: 43 Tx: 44 Tx: 45 Tx: 46 Tx: 47 Tx: 48 Tx: 49 Tx: 5 Tx: 51 Tx: 52 Tx: 53 Tx: 54 Tx: 55 Tx: 56 Tx: 57 Tx: 58 Tx: 59 Tx: 62 Tx: 64 Tx: 65 Tx: 66 Tx: 67 Tx: 68 Tx: 69 Tx: 7 Tx: 75 Tx: 76 Tx: 77 Tx: 78 Tx: 79 Tx: 8 Tx: 81 Tx: 82 Tx: 47 Tx: 48 Tx: 49 Tx: 5 Tx: 51 Tx: 52 Tx: 53 Tx: 54 Tx: 55
On Site Images Heater Placement on multiple floors Heater Placement under rolling shutter
Heater Placement & Layout Duct & Fan Layout - Packaging Heater Partially inside Packaging Plant
Basement, Sensitive Equipment Basement Wireless Temperature Sensors Placed Inside Sensitive Equipment
Detecting hidden infestations Overhead electrical junction box 1,s of adults, larvae, pupae!!
Partial/Spot heat treatment in a warehouse
Partial/Spot heat treatment in a warehouse
Sprinkler heads and opening the machines
Temperature Profile, Beetles, & Rats!!!!
Thermal Print
Heating in Mill Time (h) 1 3 4.5
Packaging Hall
Concrete floor
Concrete floor & wall Hole in the duct
Metal clad insulated wall
Temperature Profile from ground to a height of 8 feet (25 m)
THERMAL REMEDIATION Industrial Applications Food Processing Rice Mills Flour Mills Pet Food Corn Mills Cereal Processing Bakeries Warehouses Baby Food Plants Wood Packaging Tobacco Companies Organic processing plants/storages Entire structure or spot treatment
Heat Treatment of Bins & Silos Proactive Preventative & Reactive - Response
Bins & Silos Pre-loading or Pre-harvest HT On-farm bins Elevators storages Processing facilities Organic processing plants Bin/Silo types Concrete Metal GI bins Tanks
HT of bins and silos Heater Heater Hopper bottom Flat bottom
Advantages of HT of Bins/Silos S E E Shorter treatment times (4 to 12 hours) Bins/Silos in facilities Treated in rotation without shut-down On farm or warehouses no extensive sealing or evacuation No retrofitting existing transition, bin-entry
Collaborative Research Kansas State University Basic research (1999) Dr. Subi (Stored Product pests) Full scale treatment comparisons (27-29) Dr. Subi CNMA (22-6) Canadian National Millers Association In collaboration with Dr Paul Fields, Winnipeg PERC Propane Edu. Res. Council Purdue University (27-8) Dr. Maier (bins/silos) University of Minnesota (28) - Dr. Kells (bed bugs) Oklahoma State University (27) concrete silos
Spread of Heat Treatment North America USA, Canada and Mexico Europe Greece Asia India, Philippines
Effectiveness of heat treatments against insects
Typical Temperature Profile 7 Floor temperatures during heat treatment of Hal Ross flour mill August 25-26, 29 Second floor, Sensor sensor 1 (U-11) Temperature ( o C) 6 5 4 3 Sensor 2 (U-27) Third floor, sensor U-27 2 5 1 15 2 25 Time (hours)
Important Pre-heat Treatment Checklist Remove tension from drive belts to avoid stretching Perform sanitation and remove all food products Sprinkler heads should withstand 127 o C Protect heat sensitive equipment
Remove products and fumigate to reduce risk of re-infestation when products are brought back into the mill Verify that the fumigation was successful (you should not detect any live insects or stages in the products)
Heat Damage Make a list of heat susceptible equipment
Sanitation is the key Important as heat does not penetrate products well.
Apply a residual pesticide such as cyfluthrin (Tempo) or diatomaceous earth
usceptibility Differences Among Life Stages and Insect Species
Old larvae 7 6 Adults 5 Red flour beetle LT 99 (minutes) 5 4 3 2 Pupae 4 Young larvae are heat tolerant 3 2 1 5 52 54 56 58 6 Young larvae 1 Eggs 42 44 46 48 5 52 54 56 58 6 Temperature ( o C)
Fig. 2. Confused flour beetle LT 99 (min) 25 2 15 Old larvae are heat tolerant 35 Eggs Young larvae Old larvae 3 Pupae Adults 1 5 46 48 5 52 54 56 58 6 Temperature ( o C)
Cigarette beetle Time to kill 99% of the eggs as a function of temperature 7 6 LT 99 (minutes) 5 4 3 2 1 46 48 5 52 54 Temperature ( o C)
Comparison of Heat Tolerant Stages of Four Species (LT 99 in minutes (95% CL)) Species Stage 46 o C 5 o C 54 o C 598.1 165.45 37.87 Cigarette beetle Eggs (571.21-633.1) (152.62-182.84) (35.14-41.56) 43.7 432.8 81.9 Red flour beetle Young larvae (364.3-573.6) (365.3-572.6) (6.4-27.7) Confused flour beetle Mature larvae 299.46 (281.81-324.88) 9.5 (81.8-12.26) 55.71 (48.75-67.25) 69 34 Not tested Indianmeal moth Mature larvae (62-8) (29-43)
Optimizing Heat Treatments Using the right amount of heat energy Eliminating cool spots (Temp. <5 o C) Determining when to stop a heat treatment Achieving 1% kill of insects without adverse effects on structure or equipment Making it cost-competitive with other responsive tactics Delaying population rebounds
A successful heat treatment depends on... Estimating the amount of heat required (through heat-loss calculations) KSU Heat Treatment Calculator 2. Improving pest management efficacy Eliminating cool spots through uniform heat distribution (use of fans) Assessing pre- and post-heat treatment insect counts Following good exclusion and sanitation practices
Pasta facility (A) Press area: Volume: 1.55 million cu ft Surface area: 46,75 sq ft Wt of steel: 9,71, lb Flour room: Volume: 12, cu ft Surface area: 3,6 sq ft Wt of steel: 75, lb
Temperature Profiles Press Room Average Temperature Profile Start: 7/1/6; 8:3 A.M. Finish: 7/2/6; 1: A.M. Flour Room Average Temperature Profile Start: 7/1/6; 7: A.M. Finish: 7/1/6; 11: P.M. 6 n = 37 HOBOs 7 n = 12 HOBOs 55 6 Temperature, C 5 45 4 35 Temperature, C 5 4 3 3 2 25 2 4 6 8 1 12 14 16 Time (hours) 1 2 4 6 8 1 12 14 16 Time (hours)
Storgard DOME Improvements Integrated components Locking mechanism Precise to specification Reliable, convenient lure holder Stackable
Captures of Red Flour Beetles (Tribolium castaneum) Mean number of adults/trap/week Date Press room (n=35) Flour room (n=1) Outside (n=5) 5/3/26.46.4.5 6/14/26.2.42.65 6/28/26.32.65 7/11/26 (1%).9 (86%) 7/25/26.3.1.38 8/8/26.5.5 8/23/26.1.5.2
Roseli et al. (23)-KSU feed mill Cigarette beetle Red flour beetle 6 Floor 1 4 Floor 1 4 3 2 2 1 Mean no. L. serricorne (+SE)/trap/week 6 4 2 6 4 2 6 4 Floor 2 Floor 3 Floor 4 Mean no. T. castaneum (+SE)/trap/week 4 3 2 1 4 3 2 1 4 3 Floor 2 Floor 3 Floor 4 2 2 1 8/1/99 9/1/99 1/1/99 11/1/99 12/1/99 8/1/99 9/1/99 1/1/99 11/1/99 12/1/99 Date (month/day/year) Date (month/day/year)
Do we need a 24-36 h exposure time?
Quaker Oats
Do we need a 24 h exposure time? Aug 31-Sep 2, 27 6 1 Temperature ( o C) 55 5 45 4 35 n = 1 HOBOs Temperature Adult survival Larval survival 8 6 4 2 Insect survival (%) 3 5 1 15 2 25 3 35 Time (h)
End Result Heat treat for 24 h instead of 32 h Annual savings are, $25, Email, November 25, 29
Can mortality of heat tolerant stages of an insect species be predicted during heat treatment?
Thermal death kinetic model for the most heat tolerant stage Nt log 1 ( N t dt ) dt D( T ) t where N t-dt is the survival at t-dt time interval N t is survival at time t upon integration equation becomes t N t dt t dt log ( ) 1 N D( T ) No log 1 Nt log 1 N Nt N t t t t dt D( Tt) N t D( Tt ) 1 t D( Tt) where N o is the original number of insects; N t is number of larvae at time t; t is the incremental exposure time (1-min), D is the mean instantaneous D-value as a function of temperature (T t ), and T t is time- dependent temperature profile dt t Boina, Subramanyam, & Alavi (28)
Survival of old larvae of Tribolium confusum as a function of temperature Comparison of model predictions to actual Insect survival
Number of insects 12 1 8 6 4 2 N o Heating rate (1.16 o C/h) Old larvae of confused flour beetle N t T t N o Heating rate (1.19 o C/h) N t Temperature profile Predicted population Observed population T t 12 1 8 6 4 2 Temperature ( o C) 12 2 4 6 8 1 12 14 16 2 4 6 8 1 12 14 Heating rate (1.22 o C/h) Time (minutes) Heating rate (1.76 o C/h) 12 Number of insects 1 8 6 4 2 N o N t T t N o N t T t 1 8 6 4 2 Temperature ( o C) 2 4 6 8 1 12 14 2 4 6 8 1 Time (minutes)
Heating rate (2.12 o C/h) Heating rate (2.44 o C/h) 12 12 Number of insects 1 8 6 4 2 N o N t T t N o N t Temperature profile Predicted population Observed population T t 1 8 6 4 2 Temperature ( o C) 7 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 Time (minutes) Heating rate (5.31 o C/h) Heating rate (12.2 o C/h) 7 6 T t T t 6 Number of insects 5 4 3 2 N o N t N o N t 5 4 3 2 Temperature ( o C) 1 1 5 1 15 2 25 3 35 2 4 6 8 1 12 14 16 18 2 Time (minutes)
Observed and predicted survival of red flour beetle young larvae (Subramanyam & Mahroof, unpublished) Observed survival Predicted survival Temperature ( o C) 1 Data set 1 Data Set 2 1 8 8 6 6 4 4 2 2 5 1 15 2 25 3 5 1 15 2 25 3 Temperature ( o C) 1 Data Set 3 Data Set 4 1 8 8 6 6 4 4 2 2 1 2 3 4 5 1 2 3 4 5 Survival (%) 1 Data set 5 Data set 6 1 8 8 6 6 4 4 2 2 1 2 3 4 5 2 4 6 8 1 12 14 16 Time (minutes)
Temperature ( o C) RFB Projected Survival RFB Actual Survival 1 8 6 4 2 September QO 23 3.8 o C/hr 2.8 o C/hr September QO 26 1 8 6 4 2 Observed and predicted survival of young larvae of red flour beetle in a breakfast cereal plant 1 1 2.8 o C/hr 2.6 o C/hr 8 8 6 6 Temperature ( o C) 4 2 1 8 September QO 28 September QO 24 2.3 o C/hr 2.3 o C/hr 4 2 1 8 Insect survival (%) 6 6 4 September QO 25 September QO 27 4 2 2 1 1 8 2. o C/hr 2. o C/hr 8 6 6 4 4 September QO 29 September QO 31 2 2 5 1 15 2 25 3 5 1 15 2 25 3 Time (hours)
Temperature ( C) Red flour beetle Confused flour beetle 1 8 6 7.5 C/hr 7.1 C/hr 1 8 6 Roasted sunflower seed facility 4 4 HOBO 48 HOBO 45 2 2 1 6.2 C/hr 6. C/hr 1 8 8 6 6 4 4 HOBO 46 HOBO 44 2 2 Temperature ( o C) 1 8 6 4 2 5.8 C/hr 5.7 C/hr HOBO 1 HOBO 42 1 8 6 4 2 Insect survival (%) 1 5.4 C/hr 5.2 C/hr 1 8 8 6 6 4 4 HOBO 19 HOBO 2 2 2 1 8 4.6 C/hr 4.5 C/hr 1 8 6 6 4 2 HOBO 12 HOBO 7 4 2 4 8 12 16 2 24 28 4 8 12 16 2 24 28 Time (hours)
Thermal death kinetic model for young larvae of T. castaneum in DRR of facility A 22 Dry roast room (Facility A) 2 y = 5.35 + 1.17x; n = 28; r 2 =.894 18 16 14 A 12 1 8 6 Predicted LT 99 for RFB young larvae (h) 4 2 4 6 8 1 12 14 Time to 5 o C (h) 2 18 16 14 12 1 8 6 4 2 y = 18.7 -.6x 3 ; n = 28; r 2 =.837 1 15 2 25 Time above 5 o C (h) B 18 16 14 12 y = 58.28 -.78x; n = 28; r 2 =.84 C 1 8 6 4 52 54 56 58 6 62 64 66 68 7 Maximum temperature ( o C)
Predicting insect survival or mortality during a heat treatment
Integrating remote temperature monitoring data with the thermal death kinetic model Take corrective action in real time
Wireless sensor networks Typical wireless sensor network architecture
MIB/MICA2/MTS technology from Crossbow Technology Inc, San Jose, CA MICA2 Processor/Radio board MPR 4 CB MTS weather sensor boards (MTS 4 CB) MIB51 Serial interface and programming board (Base station for wireless sensor networks)
E.A.R.T.H. Software Efficacy Assessment in Real Time during Heat treatment
ds
Graph of sensor nodes (tree view)
Location: Milling facility, Dept. of Grain Science and Industry Date: 5/12/28 Total time: 35 hours Heat rate:.54 /hour Species: Red flour beetle young larvae
E.A.R.T.H. validation
ConAgra Foods, Saint Louis, MO Heat Treatment September 25-26, 29
LifeLine Foods Sensor: 1 April 2-21, 21
LifeLine Foods Sensor: 2
Hall Ross Mill Sensor: 1 KSU, May 7-8, 21
Heat versus Fumigants
Insect stage Sanitation level Treatment % Mean (SE) mortality a F P Adults 2 cm MB 1a 69.9 <.1 SF 1a Heat 9.1 (1.2)b dusting SF 1 1..4219 MB 1 Heat 98.7 (1.3) Pupae 2 cm MB 1 2.56.1568 SF 1 Heat 95.4 (2.9) dusting MB 1.6.5787 SF 98.7 (1.3) Heat 97.3 (2.7) Large larvae 2 cm MB 99.8 (.1)a 8.62.172 SF 1 (.)a Heat 96.1 (1.3)b dusting MB 99.9 (.1) 1.73.2552 SF 1 Heat 98.2 (1.3) Small larvae 2 cm MB 1a 5.39.457 SF 1a Heat 93.5 (2.8)b dusting MB 1 3.69.91 SF 1 Heat 99.4 (.3) Eggs 2 cm MB 99.9 (.1) 1.2.4145 SF 92.3 (7.3) Heat 99.3 (.3) dusting MB 99.9 (.1) 1.25.3523 SF 88.7 (1.) Heat 99.8 (.1) K-State Study (29-21) n = 3/trt Trt time=24 h for all
Summary Viable methyl bromide alternative Science and art Structural damage issues Cost competitiveness with other alternatives Not suitable for all facilities Optimization tactics should be used Heat treatment calculator Supernova EARTH Trapping/sampling to verify treatment effectiveness Make it cost-effective Sanitation and exclusion extend effectiveness of a single treatment
Thank You