The pulp and paper industry operates under extremely demanding process conditions, including high-consistency slurries, abrasive and corrosive media, foam-rich liquids, and strict safety requirements. While main stock pumping is essential, many of the most challenging duties occur in auxiliary and recovery processes, where reliability and flexibility are critical.
The following sections highlight mission-critical paper mill applications where AODD pumps offer clear technical advantages over other pump types.
Table of Contents
Broke Handling – The “Restart Specialist” for High-Consistency Pulp
Application Scenario:
When a paper machine breaks, the resulting broke is repulped in a hydrapulper and must be transferred back into the process.
Process Challenges:
- Extremely high pulp consistency (8–15%)
- Very poor flowability (paste-like behavior)
- Presence of partially defibered paper flakes
- High risk of clogging and failed restarts
Typical AODD Solution:
Large-port, high-flow AODD pumps (often assisted by air motors) installed at the hydrapulper discharge to move high-consistency broke.
Why AODD Pumps Excel:
- Excellent self-priming capability for viscous, non-homogeneous media
- Large free-passage ball valves allow paper flakes to pass without blockage
- No impeller or tight clearances, eliminating clogging risk
- Adjustable discharge pressure via air supply regulation to overcome pipeline resistance
In broke systems, the ability to restart reliably is often more critical than nominal efficiency.
Lime Milk Transfer – A Proven Solution Against Sedimentation
Application Scenario:
Lime milk (Ca(OH)₂ slurry) is widely used in recausticizing plants and wastewater treatment systems within paper mills.
Process Challenges:
- Highly abrasive slurry
- Rapid sedimentation when flow stops
- Severe hardening and solidification inside pumps and piping
- High maintenance cost for centrifugal and progressive cavity pumps
Typical AODD Solution:
An AODD pump installed below the lime slurry tank, combined with a bypass loop and operated at very low speed to keep solids in suspension, even during standby.
Why AODD Pumps Excel:
- Capable of low-speed or intermittent operation without damage
- Tolerant to temporary solidification – pump heads can be dismantled and cleaned
- Wear-resistant elastomers (abrasion-resistant rubber, PU) available
- Significantly lower recovery cost after upset conditions
For lime milk systems, survivability and maintainability outweigh hydraulic efficiency.
Felt & Fabric Cleaning Chemicals – Accurate and Leak-Free Dosing
Application Scenario:
Press felts and dryer fabrics require periodic high-pressure chemical cleaning to maintain permeability and dewatering efficiency.
Process Challenges:
- Chemicals with foaming tendencies
- Moderate viscosity
- Corrosive formulations
- Cavitation issues with metering pumps
- Leakage risk from mechanical seals
Typical AODD Solution:
Small, chemically resistant AODD pumps (PP or PVDF construction) installed next to chemical storage tanks, feeding concentrated cleaner into dilution or high-pressure water systems.
Why AODD Pumps Excel:
- No cavitation issues, even with foam-rich liquids
- Seal-less design ensures zero leakage
- Simple flow control via air pressure adjustment
- Compatible with aggressive cleaning chemicals
Lubricating & Hydraulic Oil Transfer – A Mobile and Explosion-Proof Option
Application Scenario:
Maintenance workshops in paper mills frequently transfer lubricating oil and hydraulic oil from drums or IBC tanks to equipment.
Process Challenges:
- High-viscosity fluids
- Flammable environments
- Strict explosion-proof requirements
- Need for flexible, mobile operation
Typical AODD Solution:
Explosion-proof aluminum AODD pumps mounted on wheeled carts, creating a mobile oil transfer and filling station.
Why AODD Pumps Excel:
- Inherently explosion-proof air-driven operation
- Strong suction lift, ideal for drum emptying
- Portable and versatile – one pump serves multiple assets
- Minimal operator training required
Summary Table: Why AODD Pumps Are Chosen in Paper Mills
| Application Area | Key Challenge | Why AODD Pumps Are Preferred |
|---|---|---|
| Broke handling | High consistency, clogging | Large solids passage, strong self-priming |
| Lime milk | Sedimentation, abrasion | Low-speed operation, easy recovery |
| Fabric cleaning chemicals | Foaming, corrosion | Seal-less, cavitation-free |
| Oil transfer | Viscosity, explosion risk | Air-driven, portable, safe |
Further Reading
- TAPPI – Pulp & Paper Industry Technical Resources: https://www.tappi.org
- AODD Pumps for Paper Mills: Applications & Selection: https://dpumpsupply.com/aodd-pumps-for-paper-mills-applications-selection/
