Coalescing Plate Pack

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Typically intended for use in oil and water separators, Fabco Products' coalescing plate packs help remove additional amounts of oil during the bulk water phase. We specialize in horizontal cross-flow (HCF) plate packs, which are essential in the separation and recovery of oil. Our coalescing plate packs are appropriate for use in oil, gas, petrochemical, and environmental applications - to learn more about how our HCF plate packs work, please see below.

Specifications:

Industries Served	Oil Industry Gas Industry Petrochemical Industry Environmental Industries
Liquid / Liquid Coalescer Type	Horizontal Cross-Flow (HCF) Plate-Pack
Gauge Of Material Construction	1. Fundamental Concepts of the Horizontal Cross-Flow (HCF) Plate-Pack The HCF is designed to remove additional amounts of oil from the bulk water phase. Two basic fluid dynamic principles, as well as innovative physical dimensioning, govern the HCF operation of separating liquid phases. Laminar, stable flow maintained between the HCF's corrugated plates (3/8" to 1" apart), allows convention settling (i.e. in accordance with Stoke's Law) to be much more efficient. Decreasing the travel distance to an interface (and subsequent removal) from a few feet (as in conventional settling tanks) to a shorter distance reduces the retention time required to effectively treat a given volume of water. 2. Physical Process A circular framed 3-dimensional housing containing stacks of corrugated plates acts as the working media. Made of DION® Corr-Ress Vinyl Ester reinforced with fiberglass, each pack contains plates inclined at a 45º angle (see Figure 1) and spaced from 3/8" to 1" apart. Typical capacities are shown in Figure 2. As they impinge upon the plate above, coalescence of droplets takes place and the larger droplets which are formed migrate to the top of the Plate-Pack and are removed. The materials with specified gravities greater than water separated and fall to the bottom. The HCF Plate-Pack rests upon a perforated plate which acts as a collection point for the solids. 3. Flow Scheme The oil-contaminated water stream feeds directly to the vessel. Immediately those larger particles heavier than water will normally settle to the bottom of the primary separation compartment of the vessel. A pressure drop entering into the degassing section causes most of the gas remaining to break out. AS the basic premise of HCF operation depends upon laminar flow and adherence to Stoke's Law, the flow pattern must be smoothed and a laminar flow regime established. Anything done to bring the flow within this range and to reduce the Reynold's number improves the efficiency. Prior to entering the HCF Plate-Pack the largest oil droplets have separated out although the major portion of the oil (in contaminated water flows into the Plate-Pack where the basic process begins. Upon developing laminar flow a short distance in the pack. Stoke's Law becomes applicable. As the various sized oil droplets flow through the pack, they settle to a peak in the plate bounding the upper side of the flowpath. Coalescence takes place and forms larger oil droplets which, due to greater buoyancy, migrate to the top of the Plate-Pack. Here oil flows upwards in the gutters and into a concentrated oil phase where it is skimmed off into the oil box. From a water quality standpoint, the materials remaining in the flowstream are those finer materials with a higher specific gravity than water and trace quantities (PPM) of oil which exists as oil droplets too small to be removed by the Plate-Pack. The larger materials of higher specific gravities fall through the perforated plate and out the bottom. There these particulates fall downward and settle to the bottom of the vessel. The flow, consisting of water, trace oil and trace fines (both free and oil encapsulated) moves into a chamber which contains the weir controlling the water level. Some of the trace oil which may be separated in the upward flow channel can be removed through a manual secondary oil drain on top of the water section of the vessel. 4. Maintenance The solids fall out at the bottom of the Plate-Pack due to its incline; therefore, the unit is basically self-cleaning. The temperature limit of the DION® Corr-Ress material is 300ºF.; therefore, the unit may be steam cleaned. For periodic inspection and/or replacement the HCF unit is bolted in so it can be unbolted and moved down in the vessel where the pack can be cleaned.