It could make engineering much simpler if all water traveled at the same speed.
It’s not.
The amount of water that flows into the residential system can vary throughout the day. Industrial and commercial buildings can have operating highs. Stormwater can change dramatically with weather conditions. Demand for clean water can also change according to the type of application.
To design an efficient pumping station, it is not just a case of selecting the best equipment to be able to handle a particular flow. Engineers must know the different conditions that the equipment will be used.
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Do not just think of capacity but also operational conditions
The flow that is the highest in importance however it’s just one aspect of the station’s operations. Suppose a wastewater system is designed to accommodate a high flow. The majority of the time, incoming flow may be much lower. The station still needs to function properly during these normal times.
This leads to questions on wet-well sizes, pump operation control conditions, head, and how the equipment will respond as demand changes.
A properly engineered package pumping system brings these considerations together around the actual requirements of the site instead of treating maximum pump capacity as the entire design objective.
The wastewater industry has its own day-to-day rhythm
The conditions of the influent at a wastewater liftstation serving households and businesses, or infrastructure for municipal use may change during the course of the operation.
The system has to take in wastewater and then activate its pumps in accordance with the control strategy established by the station. This requires design and dimensions of the structure as well as pumping gear, valves and piping, as well as electrical components.
The design might also include considerations specific to the site. Romtec Utilities can incorporate auxiliary systems such as grinder vaults, odor control equipment and so on depending on the requirements of the application. The result is a station built around the needs of the project, rather than a generic configuration applied to every wastewater site.
Stormwater Changes More Rapidly
Stormwater offers a completely different operating situation. A stormwater lift station could be relatively quiet during dry conditions but then experience significant increases in flow during a weather event. The station may be part of a larger flood-control treatment, detention or drainage plan, making the stormwater plan surrounding it an integral part of the design.
When designing these systems Romtec Utilities considers a variety of factors, including the required flow rate and head condition, the dimension of the system, the needs of the site, and environmental considerations.
Stations serving commercial developments may appear different than those intended for municipal stormwater applications.
The Head Conditions are Important Together with Flow
Moving 1,000 gallons is only part of the engineering problem. Engineers also need to know where the water is going to go and what resistance to overcome by the pumping system.
Pumps can operate at different head levels depending on the system’s configuration, including the piping configuration and discharge conditions, for example.
The relationship between flow rate and head is one reason that choosing a motor solely on the capacity rating is not enough. The technology of the pump and station layout must be in line with the hydraulic requirements of the particular application.
Design for the conditions the station will experience
Romtec Utilities designs and develops customized pumping systems to address the requirements of wastewater, stormwater management clean water, industrial applications, boosters, and much more. The process includes preliminary design budgeting, planning sets, budgeting along with system components, documentation, testing and startup.
The fundamental concept of engineering is that a real pumping systems aren’t operating under one set of conditions.
They should also take into consideration the project-specific hydraulic needs, as well as changing flow, demand and needs. It is important to develop a station to handle this reality.