It could make engineering easier if all water moved at the same rate.
It’s not.
The amount of water that flows into the residential system can vary throughout the day. Commercial and industrial facilities may be operating at peak times. Stormwater can change dramatically with weather conditions. Demand for clean-water also increases and decreases depending on the nature of the application.
To design an efficient pumping station, it’s not a simple matter of selecting the best equipment to satisfy a specific flow. Engineers must be aware of the conditions that the equipment will be exposed to.
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Examine the Operating Conditions and not just the Maximum Capacity
It is evident that the highest flow is an important factor however, it’s just an aspect of the operation of a station. Imagine that a wastewater treatment system was designed to handle a high volume of flow. Most of the times the flow of incoming water can be much lower. When this happens it is necessary for the station to function properly.
This raises questions about wet-well dimensions pumps, their operation and controls the head, conditions of the pump and how equipment will respond to the changing demands.
The design of a well engineered package pumps system takes into account the actual site requirements, instead of focusing on the maximum capacity of the pump.
Wastewater Has Its Own Daily Theme
A wastewater lift station serving homes, businesses, or municipal infrastructure may experience changing influent conditions throughout its operating cycle.
The system needs to be able to collect water and operate its pumps according to the control strategy established for the station. This process involves dimensioning of the structure and pumping gear, valves and piping as well electrical components.
Other considerations specific to the location could be considered in the design. Romtec Utilities can incorporate auxiliary systems like grinder vaults and odor-control equipment as required by the specific application. The result is a system built around the needs of the project, instead of a generic design applied to every wastewater site.
Stormwater can change much faster
Stormwater is a totally different type of operation. In dry conditions an apex stormwater lift station may not see much use. However, during extremely severe weather conditions, the station can see a significant increase in activity. Stations may be part of bigger flood control methods, detention and treatment plans which is why the stormwater plan is an essential part of system design.
Romtec Utilities evaluates factors including flow rates that are required along with head conditions, system size, site requirements, and environmental factors when designing the systems.
Stations that serve commercial developments could be very different from the ones designed to serve municipal stormwater needs.
Head Conditions are Important as well as Flow
The ability to move 1,000 gallons is just part of the engineering task. Engineers need to be aware of where the water is going to go and the resistance that must be overcome by the pumping system.
Elevation changes, piping configuration discharge conditions, and many other characteristics of the system contribute to the head conditions in which pumps function.
The connection between flow rate and head is that deciding on a motor solely on its capacity will not suffice. The pump’s design and station’s configuration should be aligned to the hydraulic conditions to be used for the entire process.
Design to meet the conditions that the Station Will Actually Experience
Romtec Utilities creates customized pumping system for wastewater, stormwater and clean water applications. They also develop systems for boosters, industrial and other uses. The process starts with initial design plans, budgeting, set-ups and system equipment, as well as documentation, testing and startup.
The basic engineering principle behind it is clear: the best pumping systems don’t go through their lives operating under one convenient set of conditions.
They have to contend with changing demands, flows and the specific requirements of each project. It is crucial to build a station that will cope with the challenges.
