Six Aquatic Harvesting pumps to support sustainable, decarbonised agriculture

In this case study, we’re taking you into the innovative world of automated aquatic mechanical harvesting. It’s a radical development which could change the way our food, animal food and fertilisers are grown, and have incredibly positive effects on sustainability and decarbonisation in the global environment.

What is aquatic mechanical harvesting?

It’s a way of cultivating floating crops or plants that grow on the surface of a body of water.

Our client is a dynamic agricultural start-up business. They were looking for a way to automate the harvesting of water-grown crops, and were developing a machine to gently skim the surface and collect the plants growing on the water.

A key part of this operation would be the pumps which would help by automating harvesting at a rate of between 5,000 to 20,000 litres per hour – much quicker than the manual harvesting of crops grown in the ground.

The six aquatic harvesting pumps we were asked to supply would be connected to a weir and would skim the aquatic plants from the water surface, before sending them to large collection hoppers.

Why grow plants in water?

Around the world, farmers are facing big challenges in growing the food we all eat.

The fertiliser, the seed, and the feed ingredients for livestock operations are all becoming increasingly expensive and hard to come by.

These factors are all linked to the problems farmers are having around changing climate conditions, land and water availability and shortages of labour.

In short, it’s becoming more difficult for farmers to run a profitable operation. Aquatic plants could help farmers around the world make more food using less energy, water and land.

What are aquatic plants?

These are plants which are grown in engineered ponds and then harvested automatically by robotics in a way that’s quite different to what farmers have done for centuries.

Our client calls them super plants and they are a radically different solution for the global agricultural industry.

In fact, they are unlocking cleaner and more sustainable agriculture that’s both more profitable and has considerably lower carbon emissions.

Super plants

They’re called super plants because the right varieties can produce large amounts of protein, vitamins, minerals and amino acids.

This means they can be grown to produce feed for animals, potentially for humans too, as a bio-fertiliser to grow other crops and as a soil enhancement to maintain soil health.

What’s more, these are some of the fastest-growing plants on Earth, so they need to be constantly harvested in large quantities.

This is why our client is working with North Ridge Pumps to develop an automated harvesting solution. They’re combining plant science with automation and engineering, to make the operation work profitably at scale, with no need for a huge workforce.

Our specification for this project 

Here at North Ridge Pumps, we’re not restricted to a single pump technology.

We use our expertise to offer a tailor-made solution, not something off the shelf. We choose the best pump for any particular client and application - at the lowest lifetime cost.

As these super plants are among the fastest-growing plants on Earth, they need to be constantly harvested in large quantities.

The six aquatic harvesting pumps we specified would be a key component of this automated operation, skimming the plants from the water before sending them to collection hoppers. To do this quickly and reliably, we specified six of our proven flexible impeller pumps.

What is a flexible impeller pump?

It’s a pump design based on a circular rubber impeller with a number of flexible rubber vanes contained within a casing.

The casing is actually smaller than the impeller vanes. So the vanes must be bent to get them into the pump head. This then creates a seal and chamber between each vane.

The pump head has several chambers which operate like valves. This makes the pump self-priming, and it works in the same way as a positive displacement pump.

In addition, the impeller is mounted inside the casing so the vanes bend at different angles in relation to the pump inlet and outlet.

Why our flexible impeller pump was perfect for automating harvesting 

  • Works in any location and in almost any position and still work effectively

  • High flow capacity at full motor speed even with low viscosity fluids

  • Runs at different speeds to handle different viscosities

  • As the pump works by positive displacement, the pressure is constant and the flow rate is proportional to speed

  • Gentle pumping action ensures that the fluid consistency is unaffected by shear forces – even milk, cream and thixotropic fluids

  • Flow is non-pulsating so the output can be measured accurately with a flowmeter

  • Self-primes from dry up to 6m 

  • Easily handles solids without causing any damage – for example, seeds, grapes and fruit in suspension can be safely handled

  • Reversible so tank loading and unloading can be carried out by one pump

  • Easy maintenance with only 8 parts in total, only 4 of which will wear

  • Cleaning In Place (CIP) friendly so easy to dismantle and clean

Looking to automate one of your manual processes for greater efficiency and profitability? Speak to North Ridge Pumps to see how we can help.