Scallops

Scallops are D-shaped structures strategically positioned along the inner surface of radial flow reactor vessels. They form the outer screen component, their inner surface defining the outer boundary of the catalyst bed. Installed vertically within the reactor, scallops function as flow distributors and collectors, ensuring uniform gas flow across the catalyst bed.

Inquire Now Next Product

Product Model

Scallops for Radial Flow Reactors: Optimizing Flow Distribution and Catalyst Support

Radial flow reactors are a preferred choice for gas-solid catalytic and non-catalytic reactions, known for their low pressure drop achieved through a large cross-sectional flow area, low flow velocity, and short flow path. These reactors rely on carefully designed internals to ensure optimal gas flow and catalyst bed integrity. Among these critical components are scallops, which play a crucial role in flow distribution and catalyst support along the inner vessel wall. We manufacture high-quality scallops and center pipes to enhance the performance of radial flow reactors.

What are Scallops?

Scallops are D-shaped structures strategically positioned along the inner surface of radial flow reactor vessels. They form the outer screen component, their inner surface defining the outer boundary of the catalyst bed. Installed vertically within the reactor, scallops function as flow distributors and collectors, ensuring uniform gas flow across the catalyst bed.

Key Functions of Scallops:

1. Flow Distribution/Collection: Scallops efficiently distribute incoming gas flow across the catalyst bed, maximizing contact and reaction efficiency. They also collect the gas after it passes through the catalyst, directing it towards the reactor outlet.

2. Catalyst Support: Scallops provide essential support for the catalyst packing, preventing movement and maintaining a consistent bed density.

3. Outer Screen Component: They form the outer screen, working in conjunction with the center pipe (inner screen) to contain the catalyst within the reaction zone.

Design and Construction:

Our scallops are designed for seamless integration into your radial flow reactor.

Scallops for Radial Flow Reactors

Key features include:

Material Options: Depending on the project requirements, the outer surface of the scallop can be constructed from triangular wire or perforated metal, offering flexibility to match specific application needs.

Flow Direction: Designed to facilitate flow either towards the center or outwards from the center of the reactor, providing adaptability to various process configurations.

Expanding Rings: Used to secure the scallops in place against the vessel wall during installation, ensuring a tight and stable fit.

Blind Plate: A blind plate seals the space between the scallops and the center pipe in the upper part of the reactor, preventing bypass flow.

Calculated Flow Area: The flow area of the scallops is carefully calculated to ensure stable operation across a wide range of flow rates, maintaining optimal performance.

Typically installed through the vessel's top manhole and mounted on a support ring attached to the vessel wall, scallops are designed for ease of integration. These hollow structures distribute and collect gas flow across their inner surface. Each scallop is positioned adjacent to the others, forming a set that collectively dictates the reactor's flow capacity. The flow rate through each scallop is proportional to its cross-sectional area, ensuring balanced flow distribution.

Protecting Your Investment:

To prevent hot spots on the vessel shell during high-temperature operation, we recommend applying refractory or liner materials to the shell for additional protection.

Design Parameters to Consider:

Our design process considers several critical parameters to ensure optimal scallop performance:

1. Process Parameters:

Gas flow rate and pressure drop through the catalyst are crucial for determining the scallops' inner diameter, length, cross-section, and, if applicable, the perforation percentage in the distribution system.