The process would be simpler if water was flowing at exactly the same speed.
It’s not.
The quantity of wastewater that goes into a water system is subject to change throughout the day. Industrial and commercial facilities can experience peak operating times. The conditions for stormwater can drastically change in response to weather conditions. Demand for clean-water also fluctuates depending on the application.
When designing a pump station, it is not just about selecting the best equipment to be able to handle a particular flow. Engineers must be aware of the possible conditions in which the system may be used.
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Think in Operating Conditions Think in Operating Conditions, Not just Maximum Capacity
The maximum flow is important however, it is just one aspect of the station’s operations. Imagine a wastewater system designed to provide a high peak flow. The majority of the time the flow that enters it could be significantly lower. During these normal periods it is necessary for the station to perform as it should.
This raises questions such as wet-well sizing, sizing the pump, control of head condition, the best way to modify equipment when demand shifts.
A well-designed package pumping system can bring these aspects in line with the requirements of the location, instead of thinking of maximum pump capacity as the sole design goal.
The daily cycle of wastewater
A wastewater lift station serving homes, businesses, or municipal infrastructure may experience changing influent conditions throughout its operating cycle.
The station’s management strategy will decide how the station is able to collect wastewater and operate its pumps. The dimensions of the structural components, the pumps and the piping, along with electrical components and controls all play a part in this process.
Other considerations specific to the site could affect the design. Romtec Utilities is able to incorporate auxiliary equipment such as grinder vaults or odor-control equipment, depending on the application. This results in a station that is engineered to fit the needs of the project, rather than being a generic design that can be used for all wastewater facilities.
Stormwater can change much faster
Stormwater is a completely different process. During dry weather an apex stormwater lift station may not see much use. However, during extremely severe weather events the station will experience a significant increase in activity. Stations could be a component of larger flood control techniques, such as detention or treatment thus the stormwater strategy is an essential part of the design of the system.
Romtec Utilities evaluates factors including needed flow rates and head conditions, system size, site requirements, and environmental factors when designing these systems.
The design of a station used for commercial use could be quite different from that of a station designed to handle stormwater for the municipal system.
Both head conditions and flow are vital.
Engineers also need to know what direction the water is headed and the resistance they have to overcome. Engineers also have to determine where the water will go, and what resistance to overcome by the pumping system.
The changes in elevation, the piping configuration, discharge conditions, and other aspects of the system affect the head conditions in which pumps work.
The relationship between flow and head is one reason that choosing the right pump based on its capacity rating isn’t enough. The technology of the pump and station layout must meet the hydraulic demands of the application.
Design the station for the conditions that it will experience
Romtec Utilities develops customized pumping systems for stormwater, wastewater, clean water, booster, industrial, and other applications. The process may include preliminary design and budgeting plans, complete sets of plans systems, supply documentation starting, testing and commissioning.
The basic engineering principle behind it is quite simple: genuine pumping systems don’t go through their entire lives working under one suitable set of circumstances.
They should also take into consideration the project-specific hydraulic needs, along with the changing flow, demand and demands. It is vital to create a station that is able to handle this reality.
