Complete Loadout System for Dewatered Biosolids Dryer Project

Consulting Engineer

McClelland Consulting Engineers
Fort Smith, AR

Contractor

Multi-Craft Contractors
Springdale, AR

Plant Name and Location

Springdale WWTF
Springdale, AR

General Description

Springdale is the fourth-largest city in Arkansas with a population of around 80,000 residents. The Springdale Wastewater Treatment Facility processes sewage from the surrounding region and treats about 24 million gallons per day (MGD).

As early as 2014, Springdale Water Utilities investigated changing their process from landfilling dewatered biosolids to biosolids drying. Nearby Rogers, AR had drastically reduced landfill use by adding a sludge dryer. Many municipalities across the U.S. are starting to follow suit. New technology biosolids dryers are energy efficient and create high quality fertilizer used on nearby parks, playgrounds, and farms. The Springdale dryer system also permits nearby cities in Northwest Arkansas to transport their sludge for drying at a low cost.

KWS supplied a complete storage and load out system for the project. Included in the KWS scope of supply were two 40-cubic yard storage hoppers with live bottom screw feeders to store and meter biosolids from the dewatering process to the dryer. KWS also supplied a 60-cubic yard storage hopper to handle biosolids brought it from other municipalities. After the drying process, KWS provided bucket elevators and screw conveyors to transport dried biosolids to trucks for load out.

Design Parameters

Product Type: Dewatered and Dried Biosolids
Material Density: 15 to 68 Lbs. per Cubic Foot
Rate: Up to 486 Cubic Feet per Hour
Capacity: 40 Cubic Yards (2) and 60 Cubic Yards
Duty: 5 Days a Week, 8 Hours per Day

Screw Conveyors Transfer Dried Biosolids to Truck Load Out Area

Trucks are Loaded with Dried Biosolids

KWS Advantages

The Springdale project was a design-build effort between McClelland Engineers, Multi-Craft Contractors, and KWS. Engineers from KWS made multiple site visits to propose the solution with the project stakeholders. KWS modeled the storage and load out system in Autodesk Inventor 3D, and the KWS information was helpful for the engineer and contractor to coordinate the remaining processes and disciplines. A licensed professional engineer from KWS performed startup, troubleshooting, and training for the system to operators and maintenance personnel.

KWS Special Features

KWS designed and manufactured two 40-cubic yard storage hoppers from 304 stainless steel construction to eliminate corrosion. Each hopper was installed and field-welded in smaller sections due to size and weight limitations. The 60-cubic yard hopper was engineered in larger sections and designed with a sliding cover to keep biosolids and odor contained.

All three hoppers utilized leveling screws for better storage capacity. Each hopper included a live bottom screw feeder to meter biosolids to a progressive cavity pump. The pumps fed to the dryer. After the dryer, KWS bucket elevators elevated dried biosolids to the load out area. Screw conveyors with electrically actuated slide gates distributed dried biosolids evenly into trucks below.

Testimonial

"KWS guided us through an elaborate material delivery system offering exceptional expertise and support to design, engineer and install the equipment. I would definitely partner with KWS on future projects."

Wes Johnson, Project Manager – Multi-Craft Contractors