5 october 2017

Alderwood, USA

A Class A Solution.

The Picnic Point Wastewater Treatment Facility is located in Edmonds, WA and is operated by the Alderwood Water and Wastewater District out of Lynnwood, WA. The BioCon™ dryer has been operational since 2013. The plant has a design flow of 4 MGD, expandable to 6 MGD.
The client's needs
The Picnic Point Wastewater Treatment Facility was faced with reaching plant processing capacity and was sending its biosolids to be incinerated. The challenge was to find a way to manage the biosolids produced by this facility as hauling and disposing of this sludge was difficult and becoming expensive. It was desirable to have a Class A biosolid to alleviate this concern and be more environmentally conscious.
The solution
The Picnic Point WWTF is a new activated sludge plant using MBR and a Veolia BioCon™ Dryer. Upgrading the facility with Veolia's BioCon dryer has reduced the amount of biosolid to be disposed of as well as producing a Class A biosolids, allowing to be utilized by a third party to fertilize nearby agriculture. With the help of the BioCon dryer, the plant doubled its sewage treatment capacity, ensuring the site will be able to handle increased biosolids loads for the foreseeable future.
Biocon Alderwood

Process description
The BioCon dryer is a dual-belt convective air dryer designed to be one of the safest on the market. Low drying temperatures and gentle material handling provide a safer drying
The wet biosolids are dried at a temperature of less than 350°F in the first stage; then the drying temperature is lowered as the total solids concentration increases. In order to ensure an odor free operation, wet drying air is passed through a condenser and reintroduced into the dryer.
The effectiveness of Veolia's BioCon dryer allows the Alderwood Water and Wastewater District to reduce the amount of biosolids, and to safely and easily dispose of it. This solution was executed in a small footprint and allows the municipality to produce a valuable end product, meeting Class A requirements. The newly constructed BioCon building includes an odor control system which eliminates odor. This system coupled with the production of Class A biosolids has earned the plant the support of the surrounding community.


  • Reduces biosolids disposal rate
  • Produces Class A biosolids
  • Doubles sewage treatment capacity
  • Allows for alternative sludge disposal options