Managing your Dryer And Shrink NGFA / Grain Journal Conference Aug 1 - Aug 2, 2012 Bob Marlow, The Andersons, Inc
Dryer Performance What year was your dryer built? When you talk performance, do you talk : Bushels per hour or Cost to dry, i.e. efficiency?
Pre Season checklist should include: ( # 1..SAFETY.. Lock Out / Tag out ) Inspection of all bindicators Inspect sheaves motors / blowers. If worn, replace.. Thorough inspection of all electrical by a trained / qualified electrician Service all gearboxes. Replace oil, check breather, seals, etc Inspect / replace drive belts and properly tension Lubricate motors and blower bearings Check gas train for leaks with soapy water / detector Check and tighten all linkages on Gas Valves *** Thorough check of gas train by qualified technician Inspect sweeps, idlers, sprockets, u joints.. Lubricate as needed Inspect screws / rolls for wear. Replace as needed Service blower motors. Megger motors Inspect screens / sheets for rips or tears, and replace / repair. CLEAN Check and clean shifters / turners where installed Run fans.. Check amperage loads and record Inspect inlet and outlet sensors on moisture controls if installed Inspect overall condition of dryer Start up to confirm all systems work after servicing
Pressure Washer Connection
Tower Dryer / cleaning platforms
Gas Train / Throttle valve
Operational guidelines to improve performance / preserve quality Keep plenum temperature as low as possible and use feed rate to achieve moisture target preserve grain quality Clean the exterior when material buildup is evident, as capacity could drop Consider multi pass operation when moisture levels are high Consider drying to semi wet to improve thru put, and save moisture for future blending were practical and manageable
How we track bu. thru the dryer We have a system to track dry bushels out of the dryer (s) We installed counters on our discharge screws The counters record ( in this case ) revolutions of the outlet screws. Prior to harvest, we run tests with dry stable grain to determine bushels per count. Run bushels from dryer over a scale of some sort to determine actual weight, and thus bushels Run multiple tests ( annually ), with goal to gain a level of confidence of bushels per count
Dryer Counter
Totalizer
Hourly Dryer Log ( example ) Time Wet Dry Plenum Temp Exhaust Temp Feed rate in % Counter Bin or tank 7 am 22 14.5 185 110 70 50 T-2 8 am 23 15 185 112 75 350 T-2 9 am 22 15.3 185 115 90 475 * T-2 10 am 21 15.7 186 105 95 615 * T-2 11 am noon 1 pm 2 pm
Dryer Performance / Costs
Various types of shrinks Scale variances ( inbound vs. outbound ) Aeration Shrink Mechanical Shrink Dryer Shrink Shrinks due to mixes Shrinks due to handling such as piles, dust systems, spills, etc ( all mechanical ) Quality Deterioration Bookkeeping errors Theft ( internal / external )
The BIG (4) Mechanical Dryer Aeration Quality
Typical Net House Usually puts net bushels into their DPR Typically make a one time up front adjustment to compensate for shrinks Some track the actual thru the process, but many don t Potentially at risk of shortages when actual moisture levels drop below established thresholds ( i.e. shrink taken to 15.0 on inbound corn moisture but running dryer at 14.0.. )
The gross house concept Total weight divided by common dividing factors ( 56 # for corn and 60 # for beans and wheat ) = gross bushels Those gross bushels go into our DPR ( daily position report ) Our operations folks manage the excess water,fm,and dockage on a on going, sometimes daily, basis. Requires tracking of all elements.
Frequency of reporting Shrinks Aeration : Generally 1 x per month (month end) Dryer Shrink : Daily ( usually 1 day behind ) Mechanical : Normal monthly handling / transfers happens at month end Dust truck load out or clean up daily Pile shrinks at end of building and or reclaim Mixes should be reported daily ( or when they happen ) Quality shrinks: Generally after discussion and agreement on how calculated
Shrink Factors Typical shrink tables range from 1.3 % to 1.7 % ea 1 % of moisture, and some vary depending on beginning moisture level Our company uses 1.3 or 1.4 depending on the facility, taken mostly by the 1/10 th, but some facilities by the ½ point. Market conditions drive this variable If we charge the customer at 1.4 %, and actual is closer to 1.2 %, is this extra.2 % enough for any additional shrinks you may experience? On 5 points that is worth an additional 1 %.. BULLET : unless you are tracking your shrinks ( and I hope you do ) this may not be enough, and you may find out too late.
Mechanical Shrinks Handling Transfers Pile building / reclaim Dust systems Inadvertent mixes Scale variances ( inbound vs. destination or even your own shipping scales) Theft?? ( lets hope not, but could be as simple leaving your truck load out spouts un locked and unsealed)
Example of Mechanical Shrink We handle mechanical as rec + shipments + transfers divided by 2 Multiply that number by ½ of 1 % 5,000,000 receipts 3,450,125 shipments 1,800,000 transfers --------------------------- 10,250,125 / 2 = 5,125,062.5 handled x ½ % = 2,562.53 bu. of mechanical shrink for the month
Dryer Shrinks Our standard formula = Dry bu x ( dry moisture -100) / (wet moisture -100 ) = wet bushels Example : 90,000 dry bu @ 15.5, wet moisture @ 27 %. (90,000*.845 ) /.73 = 104,178 bu wet.. So in this example, we would record 14,178 bu shrink Do periodic weigh-overs to determine bu / count, as test weight and other factors can and do influence output Take Wet and Dry samples hourly Use those samples to adjust dryer speed Can / bag up ( same ) samples to run next day for shrinks so you get optimal EMC ( equilibrium moisture content)
So, What is water worth?? In general, (1) point of moisture is worth 1.2 % Corn at $8.00 = 9.5 c / bu ( 3 c at 2.50 corn ) Wheat at $8.00 = 9.5 c / bu ( 3.6 c at $3.00 wheat ) Beans at $16.00 = 19.2 c / bu ( 7.2 c at $6.00 beans )
Does a ½ point really matter?
Aeration Shrinks Know your beginning temperatures Use your temp cables or temps from co 2 monitoring We use the following formula : Temp change *.022 *.012 * bushels = shrink Where.022 is average factor based on starting temp
Aeration Shrink Example ( cont d) 500,000 bushel wheat tank.beginning temp = 85 F Average temp at month end = 65 f Month end shrink = 2,640 bu ( 500,000 x.022x.012 x 20 deg = 2,640 ) Total est. shrink for entire cool down from harvest to winter storage temperature = 6,600 bu ( 85 f to 35 f )
Aeration Shrink on a pile Bushels = 1,800,000 Beginning avg temp = 65 f Cooled over winter to 35 f Degree drop = 30 Calculation : 1,800,000 x.022x.012x 30 = 14,256 bu Shrink cost = $114,048 @ $8.00 corn Do you turn your fans on, and walk away?
Quality Shrinks Commonly accepted rule of thumb is : For every 3 % of quality deterioration you could lose about ½ of 1 % of weight (.005 ) 500,000 bushel corn pile starts at 1 % Same pile reclaimed at 25 % Theoretical loss = 24 % / 3 = 8 x.005 = 4 % or 20,000 bushels ******** ( be careful.. )
2012 It is impossible to ignore the effects of the drought Major crop production areas are being hard hit Talk referring to 1988 or worse More than likely, if the weather persists, we will have an extremely EARLY & DRY harvest. Margins are getting squeezed at every corner. There will be stiff competition for the bushels.. Take all the talk on Aflatoxin Serious Get prepared
Some points on Aflatoxin The threshold for some form of action level is 20 ppb Cleaning can reduce toxin concentrations, as it tends to be concentrated in the smaller broken particles The discards from the cleaning process should not be used as feed After harvest, CLEAN corn can be kept at 16 to 17 % moisture levels thru the winter Cool the grain after drying, and keep at 35 f or less Sampling is the greatest variable
Questions on Aflatoxin
FDA Guidance on Toxins ( 9 page document )
Wrap up.. Our dryers are a major source of cost and potential income. Manage and track their performance carefully Our inventories are in a shrinking mode Moisture shrink is controllable The value of that shrink could exceed your margin income And last but not least. Tomorrow. The REWARD for working Safely Today
Questions Thank you