Adding water to dry canola

I got an email this week from a Saskatchewan farmer who has a question: "What is the difference in the number of bushels required to make a 40-tonne semi-load of canola if the moisture level is 10, nine, eight, seven or six per cent moisture?"

The farmer asked this question to elevator agents, agrologists and fellow farmers and has received many different answers. He wants the right answer. He asked me if I could ask around. Please email me with your suggestions and comments.

          I fiddled around with this riddle a little. Here's what I came up with: Because you're paid by the tonne, I'd keep things simple and deal with tonnes. Low moisture canola will weigh less because water alone weighs 1.6 times more than canola. Take away a bushel of water (36 kg) and the bushel of canola (22.7 kg) that replaces it weighs less for the same volume. That's why lower moisture canola will be lighter per bushel. The truck will weigh light even though it's filled it to the usual level.

If the 40-tonne truck usually holds 1,760 bushels of canola (40 times 44 bushels per tonne) at 10 per cent moisture, then the same 1,760 bushels at 9 per cent moisture will weigh 39.766 tonnes. He's giving away 0.234 tonnes per load — or about $100 if canola is $400 per tonne.

         Does this make sense?

On that note...

I've got an article going into the November Grainews written by an Alberta farmer about his experience adding water — out of the garden hose — back to his grain to boost the moisture back up. He trickled water onto the grain as he augered it into the truck. He figured out exactly how much water he needed to add, then timed his hose and his auger to see how much volume each put out per minute.

By my math, if a tonne of canola is at 9 per cent moisture and you want to bring it up to 10 per cent, you would add one per cent of one tonne of water. A tonne of water is 1,000 litres (one liter of water equals one kg). One per cent of 1,000 is 10 litres. This assumes that moisture tests are based on weight, not volume.

Based on this, the farmer above would add 400 litres of water to a 40-tonne semi load for every one percentage point of moisture he'd like to boost the canola.

Am I missing anything? Together we can crack this riddle. Please email me with your suggestions and comments.