It could make engineering easier if all water moved at the same rate.
It doesn’t.
The quality of water that is pumped into a residential system can vary throughout the day. Industrial and commercial buildings may encounter operating peaks. Stormwater conditions can change dramatically with the weather. Demand for clean-water also increases and decreases depending on the use.
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As a result, designing a pump station isn’t simply a matter of identifying one flow number and selecting equipment capable of meeting it. Engineers should be aware of the environmental conditions that the system will be exposed to.
Don’t just think about capacity but also the operating conditions
The highest flow is crucial however it’s just part of the process. Imagine that a system for wastewater treatment was designed to handle a large peak flow. Most of the times the flows coming in can be considerably lower. However, the station has to be operational during normal periods.
This raises questions regarding wet well dimensions pumps, their operation and controls and head conditions, as well as how equipment will respond to the changing demands.
The design of a well engineered package pumps system is based on the requirements of the particular site rather than focusing on maximum pump capacity.
The rhythm of daily wastewater
In the course of the lifecycle of the wastewater lift station influent conditions can change.
The system is required to collect wastewater and activate its pumps in accordance with the plan of control that is set for the station. Structural dimensions, pumping equipment, valves, piping, electrical components, and controls all play roles in that process.
Other considerations specific to the location could affect the design. Romtec Utilities is able to include additional equipment, such as grinder vaults or odor-control equipment, based on the needs of the. It is cheaper to create a station around a specific project than to apply a generic configuration for every wastewater site.
Stormwater is able to change significantly faster
Stormwater is a totally different type of operation. In dry conditions it is possible that a stormwater lift facility might not be used much. However, during extreme weather events the station will be able to witness an increase in the amount of activity. The station may be part of a larger flood-control treatment, detention or drainage strategy, making the surrounding stormwater plan an important part of system design.
Romtec Utilities takes into consideration aspects like the flow rate required along with head-related conditions, the system size, requirements of site, and environmental concerns when designing these systems.
A station that serves a commercial property could therefore appear completely different from one that is designed for a municipal stormwater application.
Both head conditions as well as flow are critical.
Engineers also need to know where the water is headed and what obstacles they have to overcome. Engineers need to be aware of where the water is going to go and what kind of resistance they will have to overcome with the pumping system.
The head of the pump is affected by a variety of variables, including elevation changes in piping configurations, discharge conditions and other aspects.
This relationship between flow and head is yet another reason why selecting one’s pump purely based on its ratings isn’t enough. Pump technology and station layout must be in line with the hydraulic requirements of the application.
Create a design that is based on the conditions the station will experience
Romtec Utilities creates customized pumping system for stormwater, wastewater and clean water applications. They also design systems for industrial, booster and other applications. The process involves preliminary design, budgeting, plan sets and system equipment, as well as documentation, startup and testing.
The fundamental engineering principle is clear: the best pumping systems don’t live their entire lives operating under one suitable set of circumstances.
They are faced with fluctuating flow, fluctuating demand, and project-specific hydro requirements. This reality should be considered when designing a successful station.