Cleaning spray tanks in and out. Ed Peachey Horticulture Dept., OSU

Transcription

1 Cleaning spray tanks in and out Ed Peachey Horticulture Dept., OSU

2 Road map Sources and causes of contamination Cleaning methods and strategies Cleaning agents and why they work Pesticide-specific cleaning directions

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4 Consequences Symptoms that appear drift-like Crop loss Illegal residues (not always visible) Environmental contamination Reduced effectiveness of the tank mix Exacerbate effectiveness Applicator exposure

5 Sources and causes of contamination

6 Sources of Contamination Solution remaining in tank or sprayer parts (ie, pressure relief system, strainers, etc) Re-dissolved residues Poly fiber tanks, old hoses Low-rate actives with highly active molecules Presence of tank mix partners

7 Surfactants and fertilizer additives When switching from a growth regulator herbicide (e.g., 2,4-D, Banvel, or Stinger) to a postemergence application on broadleaves, special care if using surfactants or fertilizer additives. good at removing these herbicides from poly tanks, hoses, and strainers and releasing them into solution.

8 Avoiding contamination Remove all liquid during the cleanout process Use pesticide resistant materials stainless steel tanks Follow proper cleanout procedures label information if provided Extension publications Tank rinsing nozzles (clean the screen) Use recommended cleaners Use a dedicated sprayer

9 Things to keep in mind Herbicide Hierarchy of Concern 1. Postemergence systemic 2. Post contact 3. Preemergence Crop sensitivity Active ingredient

10 Cleaning guidelines for the tank (after draining)

11 Core cleaning strategy Dilute Solubilize Extract

12 3 (triple) rinse method 1. Dilute Fill tank half full and flush out through the nozzles. 2. Solubilize/deactivate Repeat step 1 but include a proper cleaning agent. 3. Extract Flush final time with clean water.

13 Rinse efficacy Rinse number Sample location Nozzle Tank Drain Nozzle Tank Drain Nozzle Tank Drain % Conc Nilsson, Jorgenson, Hagenwell

14 Detailed cleaning guidelines Drain the sprayer tank and lines Rinse inside of tank, and flush boom, and lines with water for a minimum of 5 minutes.

15 General cleaning guidelines (continued) Fill the tank with clean water and one of the following cleaning solutions per 100 gallons of water: 1 gallon household ammonia, or 8 lbs trisodium phosphate cleaner detergent, or commercial tank cleaner (follow instructions on label).

16 General cleaning guidelines (continued) Flush the solution through the entire sprayer system. For growth regulator herbicides, let the solution stand overnight. Add more water to fill tank and agitate solution for at least 15 minutes and flush through the nozzles. Drain the tank.

17 General cleaning guidelines (continued) Remove the nozzles, screens, and strainers and clean them separately in a bucket of cleaning agent and water. Rinse the entire system with clean water. Apply rinsate to field

18 Do not let residues dry A sprayer should not remain empty overnight without cleaning; fill the tank with water to prevent dried spray deposits from forming.

19 Exceptions / Additional steps Beacon (primisulfuron) Peak (prosulfuron) Permit (halosulfuron) Exceed (primisulfuron + prosulfuron)

20 Beacon, Exceed, Peak, Permit Drain and flush for 5 min 2% household ammonia, circulate for 15 min, flush all lines, drain 1% household ammonia, circulate 15 min, flush all lines, drain Rinse tank for minimum of 5 minutes

21 Testing your cleanout strategy crop bioassay concentrate the solution on plots with multiple apps

22 External cleaning Spray tank surfaces may hold significant amounts of pesticide (low use-rate materials)

23 Cleaning agents

24 Function of Spray Tank Cleaning Agents Solubilize/Deactivate

25 Function of Spray Cleaning Agents Solubilizers 1. Ammonia: increases solubility 2. Detergents - phosphate groups latch onto hydrophobic components of molecules, and attach them to water 3. Oil based solvents (kerosene/diesel): - remove esters and emulsifiable concentrates best

26 Function of Spray Cleaning Agents Deactivators Chlorine bleach is a strong oxidizer - Destroys molecules - But does not dissolve herbicides Activated charcoal at 3% (wt/v) or ¼ lb AC + ¼ Det + 10 gal H Need to get it all out the tank!

27 Tank cleaners: why and when they work Water: for soluble materials Roundup Pursuit Raptor

28 Detergents and how they clean oil

29 Ammonia Household ammonia is a commonly recommended cleaning agent Penetrates and loosens deposits and residues in the spray system. Ammonia does not decompose pesticide Ammonia increases the solubility of some herbicides by raising the ph. 1-4% in water

30 Effect of ph on SU Herbicide Solubility Product Herbicide pka Water ph (25 C) x-fold ---- solubility (ppm) Accent nicosulfuron ,200 39, Muster ethametsulfuron Express tribenuron , UpBeet triflusulfuron ,000 3,670 Maverick sulfosulfuron

31 Effect of ph on herbicide ½ life Deactivation ph Valor/ Aim Cobra Chateau ½ life days Stable Stable 7 22 hrs 8.6 days Stable 9 18 min 3.4 h days Gone Courtesy R. Zollinger, NDSU

32 TSP (trisodium phosphate) 1 cup/10 gal water 8 lbs/100 gal cleaning agent, stain remover and degreaser Solution is alkaline ph in water

33 Commercial Tank Cleaners Commercial tank cleaners are recommended on many product labels and help remove water and oil-soluble pesticides. Check with the product label or with your local ag chemical dealer for available products

34 Commercial Cleaning agents Surfactant Reduces surface tension so produce can penetrate cracks crevices Sequestering agent Locks up pesticide Solubilizer

35 Chlorine Bleach & Precautions! Chlorine bleach can decompose residues of most sulfonylurea and other herbicides into inactive compounds. Rinsate containing chlorine bleach is not labeled for application to cropland.

36 Chlorine Bleach & Precautions! CAUTION!!!!! Chlorine bleach + ammonia fertilizers = dangerous chlorine gas irritating to the eyes, nose, throat, and lungs

37 Ammonia (1%) or commercial tank cleaner Accent Assure II Express Finesse Harmony Extra Resolve Oust 1% 1% 1% 1% 1% 1% 1% x

38 Ammonia (2-3%) Beacon primisulfuron 2% Peak prosulfuron 2% Aim carfentrazone, PPO 3%

39 Ammonia (4%) Banvel dicamba 4% Callisto HPPD 4% Fallow Master Glyphosate + dicamba 4% Landmaster BW Laudis Roundup + 2,4-D (isoprop salt) HPPD 4% 4%

40 Web sites with clean-out information: Peachey and Affeldt

41 Web sites with clean-out information: search: cleaning spray tank peachey saftyed/dptclean.htm t30.pdf des/crops/g04852.htm f1089.pdf