Hollow Flight Thermal Processor for Cooling Carbon Black

General Description

Maryville Carbon Solutions (MCS) provides leading technology for tire recycling and tire-derived carbon production. End-of-life tires are recycled into high performance, environmentally responsible products. By recycling and repurposing tires, MCS diverts nearly 50 million pounds of waste from entering our landfills each year. The MCS process utilizes low emission, thermal decomposition that is less taxing on the environment than traditional production methods. The MCS process can recycle over two million scrap tires annually with a facility large enough to recycle and reuse every scrap tire produced in the Kansas City metro area.

Based on experience in the carbon industry, MCS contacted KWS to collaborate on a design solution for cooling recovered carbon black. The downstream process required that the recovered carbon black temperature to not exceed 350-degrees F.

Design Parameters

1. Product Type: Carbon Black
2. Product Inlet Temperature: 1,200-degrees F
3. Product Outlet Temperature: 350-degrees F
4. Material Density: 32 Lbs. per Cubic Foot
5. Conveyor System Capacity: 26 Cubic feet per hour
6. Operating Pressure: -5 to 30 psi

KWS Advantages

KWS designed a thermal processor for MCS with the ability to handle an internal vacuum of -5-psig to up to 30-psig pressure while meeting capacity and thermal transfer requirements. The KWS thermal processor was designed in strict accordance with the ASME Boiler and Pressure Vessel Code. As an ASME certified pressure vessel manufacturer, KWS was able to provide an ASME code stamp for the trough, trough jacket, and hollow flight screw prior to shipment.

Special Features

In lieu of the traditional U-trough design, KWS implemented a tubular “pipe-in-pipe” jacketed trough to handle the internal pressure requirements for an inert conveying environment and the external pressure required for pumping cooling water through the jacket.

The KWS hollow flight screw design provides maximum heat transfer and cooling of carbon black. Cooling water enters the screw on the tail end and follows an exact path through the hollow flights before returning down the center pipe of the screw. A dual-pass rotary union is mounted on the tail shaft for the inlet and discharge of cooling water.

KWS exclusive slider base trough end allows axial travel along the length of the thermal processor for the hollow flight screw to expand and contract. If thermal expansion is not properly accounted for, the shaft and screw will be subjected to cyclical bending loads causing premature failure of the thermal processor.