Dissolved Air Flotation: Separating Solids from Wastewater Article Overview Article Type: Informational Primary Goal: Provide municipalities, design engineers, operators, and equipment manufacturers with a practical, technical reference for selecting, designing, operating, and troubleshooting dissolved air flotation systems to optimize solids separation, footprint, and lifecycle cost for municipal and industrial wastewater applications Who is the reader: […]
Introduction In municipal water and industrial wastewater treatment facilities, pressure instrumentation is the sensory nervous system of the process. Yet, a surprising number of process upsets, pump protection failures, and chemical dosing errors can be traced back to a single, often overlooked component: the diaphragm seal (or chemical seal). Engineers frequently treat these isolation devices […]
Introduction In municipal and industrial wastewater treatment, the precision of chemical dosing is directly linked to process compliance, yet the longevity of the dosing equipment is often compromised by material mismatching. A common point of failure in chemical feed systems is not the mechanical drive mechanism, but the degradation of wetted parts due to unforeseen […]
Introduction One of the most persistent misconceptions in municipal wastewater engineering is that positive displacement (PD) pumps are immune to the hydraulic sensitivities that plague centrifugal systems. While it is true that double disc pumps (DDP) are robust, self-priming, and capable of handling high solids, they remain subject to the fundamental laws of fluid mechanics. […]
Introduction to Submersible Pump Metallurgy One of the most persistent and costly challenges in modern wastewater management is the premature degradation of submersible pumping equipment due to shifting influent chemistry. As water conservation efforts reduce flow rates, wastewater becomes more concentrated. Simultaneously, longer retention times in force mains and collection basins accelerate septicization, leading to […]
Introduction One of the most persistent and costly failures in municipal wastewater collection systems is not the mechanical failure of the pump itself, but the failure of the intake hydraulics. Engineers frequently specify high-efficiency, robust pumping equipment, only to place it into a geometry that guarantees reduced lifespan. A significant percentage of premature bearing failures, […]
Introduction Municipal engineers frequently underestimate the complexity of chemical injection at remote lift stations. While the primary sewage pumps receive the bulk of the design attention, the auxiliary chemical feed systems are often the critical defense against the wastewater industry’s most pervasive enemies: hydrogen sulfide ($H_2S$) corrosion, noxious odors, and Fat, Oil, and Grease (FOG) […]
Introduction Peristaltic pumps (often referred to as hose pumps or tube pumps) are frequently selected for their ability to handle aggressive chemicals, viscous sludge, and shear-sensitive fluids in water and wastewater treatment. However, despite their mechanically simple design—typically involving a rotor compressing a hose—they present a unique set of operational challenges. A surprising industry statistic […]
Introduction In the complex hydraulics of a modern wastewater treatment plant (WWTP), the peristaltic pump—often referred to as a hose pump or tube pump—occupies a critical niche that centrifugal technologies cannot fill. While engineers are intimately familiar with pump curves for water transfer, the specification of positive displacement equipment for abrasive sludge or off-gassing chemicals […]
Stormwater Treatment Systems: Managing Runoff Effectively Stormwater treatment is central to meeting MS4 permits, TMDLs, and growing urban flood risks while protecting receiving waters. This practical guide gives municipal engineers, operators, and manufacturers the selection, sizing, operation, and verification details you need, covering bioretention, permeable pavement, constructed wetlands, hydrodynamic separators, media filters, and hybrid approaches […]