Baffle systems are commonly used in water treatment facilities to improve or augment the hydraulic and treatment efficiency of ponds, tanks reservoirs and other water containment devices.  These devices are typically poor structures for use as treatment mediums having a problematic geometry resulting in short circuits and dead spots.  Baffles will redirect and control the flow to eliminate this issue.

The careful installation of baffle systems can economically and significantly improve treatment efficiency, limiting the need for substantial expenditure at facilities where there is insufficient room for larger ponds or other treatment facilities to be constructed.

Floating baffles offer the flexibility of being able to modify or refine the configuration post installation.  Baffle systems are utilised at both waste water and potable water treatment facilities and can be configured with either permeable or impermeable skirts.

TYPES OF BAFFLE INSTALLATIONS

Potable Water Treatment with Baffles

Using fixed or floating baffle systems in potable water treatment facilities can greatly enhance water treatment by increasing the chlorine/chemical contact time, while making the most efficient use of the water treatment method.  Fixed baffles are normally fitted to enclosed structures and floating baffles are used in treatment ponds and dams.  The baffles create current directing walls that channel flowing water over specific paths that increase the amount of time that water is exposed to treatment processes.  The baffles can greatly reduce water treatment chemical requirements by improving mixing.

Waste Water Treatment with Baffles

In waste water there are a number of applications for baffle systems, most notably the segregation/separation of aerators with a pond system, the sub-division of large ponds and installation in detention ponds to increase detention time.

DETERMINATION OF BAFFLE REQUIREMENTS

The determination of baffle requirements for a particular installation can be undertaken using complex hydrodynamic computer modelling using input data sourced from strategically placed current meters.  From this information cross sectional velocity profiles and plan is developed.  This reveals low flow areas, short circuits and dead spots.  Whilst not as accurate, surface flow can also provide some indication of these areas – flow generally contours to the surface in large ponds, the highest velocity being in the centre of the stream, with the flow rate decreasing closer to ponds banks and the bottom.

Dead spots can be identified by carefully monitoring the surface flow; for example, if there is a tendency for weed to accumulate at certain times of the year on a pond, this will often concentrate and radiate from the dead spots.

By using pond flow data, baffles can be positioned to better utilise the pond area and minimise shortcutting of the flow stream from the inlet to the outfall.

TYPES OF BAFFLES

Fixed Curtain Baffles

Fixed baffle curtains use a supported geo-membrane material to make a vertical impermeable barrier inside a tank or a reservoir.  They are secured to the roof and floor of the water impoundment, and are often fitted with flow through windows to direct the flow on a specific path.  They are most frequently manufactured from HDPE (1 to 2mm) geo-membrane material.

Floating Baffle Curtains

Floating baffle curtains are used in a wide range of installations and applications.  They are most frequently used in aeration and detention ponds.

They also are suited for installation in lined ponds as they are contoured to the banks and ballasted using galvanised or stainless chain enclosed in a pocket (minimising linier damage), and can usually be constructed with the same material as the pond is lined with.

This blog post is intended as a guide only, and should not be relied upon as professional and/or legal advice.  Argyle Commercial will not be held liable for any damages or losses caused by using information provided in this post as a basis for any decision where any such damages or losses may result.