PEI Potato Solutions

Company Overview:

PEI Potato Solutions (PPS) provides a full potato wash service to farmers of PEI before the potatoes are sold to Cavendish Farms. This service includes washing, sorting, separating rot, as well as metal and foreign material removal. The service is provided so that farmers can achieve a higher grade when selling their product to Cavendish Farms.

Problem Statement

PEI Potato Solutions is unable to increase their potato washing capacity due to environmental, economic, and volumetric restrictions, which govern the fresh and recycled water appropriation within their closed system. Preliminary focus was on reducing the fresh water consumption of the plant.

Spuddy Waters team with Client during their presentation at the School of Sustainable Design Engineering

The Spuddy Waters project Team, Ryan Myette, Angela Court, Tristan Dawson, Peter Doiron, worked out the problem of PEI Potatio Solutions and created a system for maintaining and improving the clients potato washing procedure.

Design Solution

For the design solution, It was decided that cleaning the recycled water would benefit the client the most as it will not affect the washing facility and will lower the fresh water consumption.

The original idea was to stagger the heights of the barrels, where
the water would be gravity fed through the system.

Further investigation into the specs of the filter indicated that the filter has an optimal flow rate and pressure. Therefore, a utility pump had to be purchased in order for the filter to reach its full potential of sediment removal. The pump is placed in the first barrel and would increase the flowrate through the filter.

After the configuration above was tested, it was noticed that the water exiting the filter was not creating a cyclone. A cyclone at the exit indicates a good velocity of the water in the filter, resulting in sediment separation. It was determined that there was not enough pressure given by the utility pump to create an ideal cyclone in the filter. A jet pump was purchased to run in series with the other pump.

The utility pump now primes the jet pump and pressure and flowrate increase.

The jet pump now supplies enough water to maintain the flowrate for ideal sediment removal.

Break down of Prototype

Water Barrels

Three 55 gallon barrels were used to simulate the lagoons PPS use to manage their water.

Mechanical Filter

Mechanical Filter Stand

Electronic Flocculation

The filter cleans the water that the PEI Potato Solutions workers can use again to clean more potatoes. They used the Centrifugal filter as means to design their prototype.

After the water has been processed through the Spuddy Waters prototype filter, the results are clear, this filtration system is well designed.

Biological Filtration Method

Cattails are self-sustaining and self-propagating which means they would require little
work on them, except by planting them. They are a natural filter of BOD which is the main
reason for the bad smell.

Testing

  • Suspended Solids Test
  • Vacuum filtration

Results of Filtration

Potato water before and after filtration system.

Conclusion

The water treatment process demonstrating the best results consists of the water passing through the electronic flocculator settling out in the final lagoon before being pumped through the mechanical filter. This configuration of the components is suggested to be implemented at PPS; however this will include cattails as biological filtration in the lagoon prior to being pumped to the mechanical filter.