It would make engineering easier if all water moved at the same speed.
It’s not.
The amount of wastewater that enters a residential water system can change throughout the day. Commercial and industrial facilities might be operating at peak times. Stormwater conditions can alter dramatically in response to the weather. The need for clean water can also change according to the application.
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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 must understand the conditions that the system will be subject to.
Think beyond capacity maxima, as well as operating conditions
It’s obvious that maximizing flow is an important aspect, but it only represents an aspect of the operation of an infrastructure. Imagine that a wastewater treatment system was designed to handle a large volume of flow. Most of the times, incoming flows may be significantly lower. During those normal operating periods the station should be functional.
This raises questions regarding wet-well sizing, pump operation, control conditions, head, and how the equipment responds to demand fluctuations.
A properly designed package pumping system can bring these aspects in line with the requirements of the facility instead of treating maximum pump capacity as the main design objective.
The daily cycle of wastewater
In the life-cycle of the wastewater lift station the conditions of the influent can change.
The system has to collect the wastewater and turn on its pumps in line with the established control plan for the station. This requires dimensioning of the structure and pumping gear, valves and piping, as well as electrical components.
The design may also include aspects specific to the particular site. Romtec Utilities can incorporate auxiliary equipment such as grinder vaults and odor-control equipment when required by the application. It is cost-effective to design a station around a specific task than to use the same configuration for each wastewater site.
Stormwater can change much faster
Stormwater is a different operating situation. A stormwater facility can be relatively quiet during dry conditions, but then experience a large inflow of water during a severe weather occasion. It could be an element of a larger flood-control, detention, treatment, or drainage plan, which makes the surrounding stormwater plan an important part of system design.
Romtec Utilities evaluates factors including flow rates that are required as well as head conditions, size of the system, site requirements, and environmental aspects when developing these systems.
The layout of a station designed for commercial projects could differ significantly from the design of a station built to manage stormwater in municipal areas.
Both head conditions and flow are vital.
Moving 1,000 gallons is only one aspect of the engineering challenge. Engineers also have to determine where the water will be going and the resistance that must be overcome by the pumping system.
The head condition of the pump can be affected by a variety of variables such as elevation changes and piping configurations, discharge conditions and other system features.
The relation between flow rate and head is a reason why deciding on a motor solely on its capacity rating does not work. The technology of the pump and station’s configuration should be aligned to the hydraulic conditions throughout the application.
Plan for the conditions that the station will encounter
Romtec Utilities creates customized pumping system for stormwater, wastewater and clean water systems. They also develop systems for industrial, boosters and other applications. The procedure may involve preliminary design and budgeting and complete set of plan sets and system supplies, documentation, startup, testing, and commissioning.
The principle behind the design is simple Pumping systems don’t spend their entire lives working under the same set of conditions.
They face changing flows, changing demands, and project-specific hydraulic needs. It is important to build a station that will manage this challenge.