Shaftless Screw Conveyor for Biosolids Load Out St. Clair WWTP in St. Clair, PA

General Description

The St. Clair Waste Water Treatment Facility is a small plant servicing the borough of St. Clair, PA and is one of several in Schuylkill County. This WWTP is sized to serve its 3,000+ residents. Over the years periodic maintenance projects and upgrades have been performed with the latest project being the addition of a new solids load out building with a completely automated load out system. The new system dewaters sludge using a rotary press that directly feeds a KWS Environmental shaftless screw conveyor. The sludge is then transferred to 20-yard rollout containers in an adjacent room. The load out building is heated and cooled to protect the equipment from weather. The conveyor system included an inclined shaftless screw conveyor, supports, and control panel.

Design Parameters

1. Product Type: Dewatered Biosolids
2. Material Density: 60 Lbs. per Cubic Foot
3. Capacity: 61 Cubic Feet per Hour
4. Duty: 5 Days a Week, 8 Hours per Day

KWS Advantages

KWS Environmental has executed several successful projects over the years for the St. Clair Water Authority and the team had full confidence in KWS’s abilities. Engineers from the consulting engineering firm, contractor, water authority and KWS worked very closely to fit the equipment into the limited space provided. KWS designed an inclined shaftless screw conveyor to accommodate the building layout and mating equipment. KWS also provided a control panel so the operators could have both manual and automatic control. An engineer from KWS Environmental helped the Contractor during the installation phase to make sure the new conveyor went in without any problems.

Special Features

KWS took special care to make sure that the design provided enough room at the conveyor inlet to interface with the rotary press drop chutes while still inclining high enough to fill containers. The conveyor structure supports were designed to be bolted together in the field so there would be no welding or field modification.

The shaftless screw conveyor utilized the exclusive KWS Microalloy shaftless spiral that is harder and tougher than any other spiral in the industry. Under-speed sensors and an emergency pull cord safety stop switch help protect personnel and the process. As a further safety precaution, each conveyor cover is secured with safety bolts that require a special tool to remove.