Valve World Americas February 2025 | Page 22

TECH TALK

Flow Control Innovations in Wastewater Treatment

This article examines how high-efficiency pumps and valves — including peristaltic hose pumps , metering pumps , progressive cavity pumps and pinch valves — are improving plant operations and reducing environmental impact .
By KCI Editorial
Wastewater treatment facilities face increasingly complex challenges in managing diverse chemical processes , ensuring environmental compliance and optimizing operational efficiency . As the industry evolves to meet stricter regulations and sustainability goals , the demand for sophisticated flow control equipment has grown .
This article explores recent developments in flow control technology for wastewater treatment , including contributions from companies such as Valmet . Wastewater treatment involves multiple stages : preliminary treatment , primary sedimentation , secondary biological treatment , and tertiary filtration and disinfection . Throughout these stages , various chemicals are used , including pH neutralizers , anti-foaming agents , coagulants , flocculants and disinfectants . Each chemical presents unique challenges in terms of pH levels , viscosity and material compatibility .
Controlled chemical dosing is crucial for efficient treatment . Optimal dosing improves performance , reduces costs and minimizes environmental impact . Key requirements include adjustable dosing based on real-time monitoring , accuracy , chemical compatibility and reliability in harsh environments .
Precise Chemical Dosing
Accurate chemical dosing is crucial in wastewater treatment . Excessive dosing can lead to unnecessary chemical costs and potential environmental issues , while insufficient dosing may result in ineffective treatment . Key factors in optimal dosing include :
1 . Adjustability based on influent quality and flow rate 2 . High accuracy across various flow rates 3 . Chemical compatibility to prevent equipment degradation 4 . Reliability in corrosive environments
Advanced flow control solutions must address these factors to ensure efficient , cost-effective and environmentally sound wastewater treatment .
Metering Pump Advancements
• Energy-efficient motors with variable speed drives
These features can improve dosing accuracy while also contributing to reduced downtime and lower operational costs .
Metering pumps play a vital role in precise chemical dosing in wastewater treatment . Recent advancements in this technology , as exemplified by pumps such as those in Valmet ’ s Flowrox™ FXM series , include :
• Multiple Control Options : Local or remote operation via various signal types allows for integration with plant control systems .
• Positive Displacement Design : This ensures consistent output volume regardless of discharge pressure , which is critical for maintaining treatment efficacy .
• Self-cleaning Mechanisms : Features such as compression points that act as non-clogging valves can reduce maintenance requirements and ensure reliable operation .
• Multi-chemical Compatibility : The ability to handle a range of media makes these pumps suitable for various treatment stages .
Modern metering pump designs often incorporate additional features to enhance operational safety and efficiency , such as :
• Only the tube and tube fittings are in contact with the process medium
• Integrated leak detection systems
Peristaltic Pump Technology
Peristaltic pumps represent an alternative approach to fluid handling in wastewater treatment . Their operating principle is straightforward : 1 . A flexible hose is fitted inside a circular pump casing . 2 . Rollers attached to a rotor compress the hose . 3 . As the rotor turns , the compressed part of the hose forces fluid through . 4 . The hose ’ s restitution creates a vacuum , drawing in more fluid .
This design offers several advantages in wastewater applications :
• Reduced Contamination Risk : The hose is the ( main ) contact element with fluid .
• Versatility : Suitable for handling abrasive slurries , corrosive chemicals and fluids with high solid content .
• Dry Running Capability : The pump can run dry without sustaining damage .
• Gentle Fluid Handling : Suitable for shear-sensitive fluids and beneficial for media containing live microorganisms used in biological treatment processes .
22 Valve World Americas | February 2025 • www . valve-world-americas . net