Corrugated Plates Separator. The First Choice for Primary Treatment of Produced Water.
The corrugated plates separator is the first option to consider in gravity separation of oily waters, especially those effluents with low presence of suspended solids, such as produced waters. The absence of moving parts and a greater surface area, in lower volume, makes it the most compact and efficient equipment selection for separation of water and oil.
Its residence time is approximately one fifth of a conventional API separator.
Operation of a Corrugated Plates Separator Tank
The oily water enters the corrugated plates separator unit CPS into the inlet compartment which in turn acts as a pre-sedimentation chamber for the suspended solids. In this chamber, the incoming effluent speed is reduced and is directed toward the entrance of the plate package where it is contacted with large oil droplets leaving the package in upflow. The oily effluent, with small droplets and solid particles remaining, then enters the plate pack where a laminar flow type is set.
Corrugated Plates Pack
The package of corrugated plates is the heart of the equipment, it is designed to increase the surface area by placing the plates in parallel by distributing the total flow in multiple parallel channels facilitating the coalescence and separation of smaller oil droplets of effluent. The typical spacing between plates is 3/4″ of an inch, larger spacings may be used for effluents that can create plugging of the pack due to higher solids concentrations. The effluent flow is evenly distributed between each of the channels of plates and downwards at an inclination of 45 degrees.
The oil in each of the channels of plates ascends to the crests of the corrugated plate and flows counterflow to the inlet of the package, and then ascends to the surface of the tank. Solids, on the contrary are deposited in the valleys of the plates and flow down along with the effluent to settle to the tank bottom.
The separation is based on Stokes’ law and depends mainly on the difference in specific gravity between the oil and the effluent and the viscosity of the effluent, which are temperature dependent. The droplet diameter is also very important in equipment design factor, which has historically been considered at 60 microns as the most commonly used.
Separated oil forms a layer on the water surface which is continuously removed by means of a weir.
The clean effluent leaves the plate package and flows upwards through the clean effluent compartment to a weir and is continually discharged from the unit by gravity.
PACKS MATERIALS OF CONSTRUCTION
The selection of plate materials is based on the temperature of the effluent. Fiberglass is the option for effluent temperatures bellow 45 ° C and stainless steel for higher temperatures.
Among the most common applications of corrugated plate separators are the following:
- Produced Water
- Ballast Water
- Run Off Water
- Equipment and Truck Wash