Project Name

Client

Nova Scotia Lands Inc.

Location

Pictou Landing, Nova Scotia

Year

2022

Nova Scotia Boat Harbour Aeration

Project Summary 

Aquatic Engineering Canada sent a team to Nova Scotia to work alongside the local indigenous group to install a 60-diffuser system at the 45-acre Boat Harbour Aerated Stabilization Basin. The goal of the project was to improve DO levels, reduce BOD, COD, TSS, phosphates, and nitrogen-based contaminants, and improve effluent water quality. Converting the lake from surface aerators to fine-bubble bottom diffusers has tripled oxygen transfer efficiency, at the same time reducing the system from 600 HP to 15 HP.  

Boat Harbour ASB Aeration Project 

Project Objective 

  • Install a turn-key bottom diffused aeration system to the 45-acre Aerated Stabilization Basin (ASB) to increase the dissolved oxygen (DO) and prevent septic conditions.

Methods 

  • Install 60 Can-Air Mega diffusers  

  • Install 20 3/4HP KM 200C compressors (total HP= 15; total CFM @ 10 psi= 136)

  • Install custom lengths of AquaTube airline 

  • Install a custom built 10' x 10' shed with fans and ventilation to house all compressors and related equipment in one easy-to-access space.

  • Work with the Pictou Landing First Nations community to hire boat captains and equipment operators and help with the installation.

Challenges 

  • 40% sludge volumes within the lagoon 

  • Increase DO with reduced HP (compared to the previous system)

  • Tight project timeline 

  • Material shortages 

  • Equipment rental shortages

Timeline

Project awarded: March 2022

System commissioning: July 2022

Planned Solutions 

  • Significant sludge volumes resulted in variable and shallow depths. Aeration efficiency improves with increasing depth, therefore, the diffuser must be placed in deep zones with relatively equal depths for even performance. 

  • The existing system relied on several +50 HP surface aerators. AEC planned to install a system to deliver more than 335 kg O2/day using only 15 HP. 

  • The system is designed with equipment readily stocked and manufactured in our warehouse.

  • Additonal material and equipment was ordered in advance to avoid delays.

  • Several materials and rentals to be supplied by locals  

Results 

  • The system became operational in July 2022. Operators have stated that DO levels have improved and will continue to monitor changes.