It would make engineering simpler if all the water flowed at the same speed.
It’s not.
The quality of water that is pumped into a residential system is likely to fluctuate throughout the day. Industrial and commercial buildings could have operating highs. Stormwater flow is affected by weather conditions. Clean-water demand also rises and decreases based on the usage.
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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 need to be aware of the variety of conditions that the system is expected to face.
Consider the Operating Conditions and Not Just the Maximum Capacity
The flow rate is of course crucial but it’s just one aspect of the station’s operation. Imagine that a wastewater treatment facility was designed to handle an enormous maximum flow. In the majority of cases the flow inflow is less. During these normal periods however, the station has to perform as it should.
This raises questions about wet-well dimensions pumps, their operation and controls, head conditions and how equipment will respond to changes in demand.
The design of a well designed package pump system is based on the actual site requirements, instead of focusing solely on the maximal capacity of the pump.
The Wastewater Industry has its own daily rhythm
Throughout the life of the wastewater lift station the conditions of the influent can change.
The station has to have an appropriate control system that permits the system to turn on the pumps and collect the wastewater. The dimensions of the structural components, pumping equipment and piping, and electrical components and controls, all play an important role in this process.
The design can also incorporate factors specific to the area. Romtec Utilities will incorporate any extra systems, including grinders, vaults and odor control devices when needed. The result is a station designed to meet the needs of the specific project rather than being a generic design applicable to all wastewater sites.
Stormwater Can Change Much Faster
Stormwater has a distinct type of operating situation. A stormwater lift-station may have a low level of activity during dry weather conditions, but it will experience significantly higher inflows when a weather storm occurs. The station could be a part of a comprehensive flood-control plan or a detention, treatment or drainage plan.
When constructing these systems Romtec Utilities considers a variety of elements, including the flow rate that is required and head condition, the dimension of the system, the needs of the site and environmental factors.
A station for a commercial area may, therefore, look quite different from one engineered for a municipal stormwater application.
Head conditions are important along with Flow
Moving 1,000 gallons is only part of the engineering problem. Engineers also need to know where the water will go, and what resistance to overcome by the pumping system.
The head of the pump is affected by a number of factors which include elevation variations and piping configurations, discharge conditions and other system features.
This relationship between head and flow is one reason that choosing the right pump based on its capacity rating isn’t enough. Technology and station layout must be in line with the hydraulic requirements of the particular application.
Design the station for the conditions that it will have to endure
Romtec Utilities develops customized pumping systems for wastewater, stormwater, clean water and industrial applications. and other applications. Its process may include budgeting and design in the beginning, complete plans, system supply, documentation and startup, testing and commissioning.
The premise behind the system is as simple as this pumping systems can’t spend their entire lives working in a set of favourable conditions.
They face changing flow, fluctuating demand, and the specific requirements of each project. The best station needs to be designed for this reality.
