Ash Conveyor System for Wheelabrator Waste-To-Energy at Baltimore, MD

General Description

The Wheelabrator Baltimore waste-to-energy facility converts up to 2,250 tons of post-recycled municipal waste from Baltimore area homes and businesses to fuel for generation of over 65 megawatts of clean, renewable electricity. The fuel is sold to the local utility and the electricity generated supplies the electrical needs to 40,000 homes as well as its own operations. By using local waste as a fuel to create a local-energy ecosystem, the facility diverts waste from landfills and lowers greenhouse gases by recycling metals, offsetting the use of fossil fuels, and reducing methane emissions from landfills. Wheelabrator has been an integral part of Maryland’s energy, environmental and economic infrastructure, providing sustainable waste management for 34 years.

The Baltimore facility was originally commissioned in 1985 with electrostatic precipitators (ESP) for each of its three combustion lines. New air pollution control systems were being added. KWS provided systems to convey fly ash from the new filter baghouses to existing drag conveyors.

Design Parameters

1. Product Type: Fly Ash
2. Material Density: 30 to 60 Lbs. per Cubic Foot
3. Capacity: 70 to 150 Cubic Feet per Hour
4. Duty: Continuous

KWS Advantages

KWS worked closely with the engineering team at Hitachi Zosen Inova to ensure the interface between our conveyors, and location of supports were designed properly to avoid any inference in the field. KWS utilized the latest 3D CAD modeling techniques to model the complete system to help determine all support locations during submittal process and orientation of our equipment. As a result, the installation phase went very smoothly. A certified KWS engineer performed equipment startup and operator training before the system was put into successful service.

KWS Special Features

To enhance performance and extend service life of our equipment, troughs were designed with replaceable abrasive resistant AR400 liners across the full length of the conveyors. AR400 is a hardened steel with Brinell Hardness (BHN) averaging 400 BHN, 98-percent harder than A36 carbon steel. The liners are stitch-welded to the trough for easy removal and replacement. The same abrasive resistant AR400 plate was used for the screw flighting for maximum abrasion resistance to eliminate frequent maintenance and increase longevity of the screws.

Each conveyor is equipped with a Milltronics Zero Speed Switch. The zero-speed switch warns of equipment malfunction through detection of speed change or zero speed and signals through contacts to shut down machinery in case of a slowdown or failure. The process may be halted to prevent damage or plugging of other conveying or processing equipment. The system’s reliability makes it a cost-effective way to protect valuable conveying and process equipment.