Lamella Plate Settler

Inclined channels raise settling capacity in four connected ways, and each of them is explained below. The channel geometry inside a Lamella Plate Settler controls the flow path and shortens the distance a particle has to fall, the inclined arrangement multiplies the projected settling area, the modular pack construction allows that area to be scaled or retrofitted, and the three together lift the throughput a given footprint can handle. Every Lamella Plate Settler is shop assembled, water tested before dispatch and available with CE and ISO certification.

Customized Service

We size a Lamella Plate Settler from the numbers that matter, which are the design flow, the solids concentration, the character of the particles and the space the unit has to fit into. From these we fix the plate area, the channel spacing, the hopper volume and the inlet distribution arrangement.

Where settling behaviour is not yet known, our laboratory establishes the coagulant type, the dose and the achievable rise rate by settling and jar testing before the Lamella Plate Settler is dimensioned. Sizing on measured data rather than on assumption is what keeps a unit from being either short of capacity or needlessly large.

Configuration items we routinely adjust include pack type as flat plate or hexagonal tube, channel spacing, plate and structural material, corrosion protection, hopper angle and hopper count, sludge valve or pump arrangement, launder and weir layout, access platform design, and the interface between the Lamella Plate Settler and any existing tank or dewatering unit.

Certification and Quality Documentation

Our Lamella Plate Settler is available with CE and ISO certification. Material traceability records, welding and coating reports and dimensional inspection sheets are compiled for each unit and issued in whatever format the project documentation calls for.

Every Lamella Plate Settler is water filled in our workshop to confirm that the tank is tight, that the pack sits square inside the clarification zone and that the weirs run level along their full length. A unit that has already been filled and checked is a unit that can be commissioned quickly once it reaches site.

Installation and Technical Support

Drawings covering foundation loads, nozzle positions, lifting points and maintenance clearances are issued with every Lamella Plate Settler well ahead of shipment, so civil work and pipe routing can be completed while the equipment is still in production.

Our engineers support levelling, connection, first filling, dose setting and tuning of the sludge discharge cycle, either on site or remotely. After handover we remain available for troubleshooting, replacement packs and advice whenever your flow or water quality changes.

1. Inclined Channel Structure That Controls the Flow Path

Each pair of adjacent plates in a Lamella Plate Settler forms a long narrow passage set at a fixed angle. Hydraulically this passage behaves as an inclined tube. The cross section stays constant, the water is guided along the full length of the channel, and there is no opportunity for the short circuiting that lets part of the flow cross an open basin in a fraction of the design time.

The channels of a Lamella Plate Settler are normally set at about 60 degrees from horizontal, and that angle is a deliberate compromise. A shallower setting would project more area onto the horizontal plane but would allow sludge to rest on the channel floor. A steeper setting would keep the surface clean but give away projected area. At about 60 degrees the deposited solids slide down continuously under their own weight while the projected area remains close to its practical maximum.

Inside every channel of the Lamella Plate Settler the clarified water rises while the collected sludge slides down along the same surface. This counter current arrangement removes the need for any separate sludge transport route and keeps mechanical equipment out of the pack entirely.

Because the clear spacing between two plates is measured in tens of millimetres, flow inside a Lamella Plate Settler stays laminar. Laminar flow suppresses the eddies and density currents that re-suspend settled material in a conventional tank, and it protects chemically formed floc from being torn apart before it reaches a surface. Where a stiffer self supporting element is preferred, the flat plate pack can be replaced by hexagonal inclined tube modules without changing the working principle of the Lamella Plate Settler.

2. Multiplied Settling Area Within the Same Plan Area

Capture of a particle in any gravity settler depends on the horizontal area presented to the flow rather than on the depth of the tank. This is the reason a Lamella Plate Settler can be shallow and still perform, because every inclined channel contributes its own horizontal projection to the total settling area.

The projected area of a single plate equals its surface area multiplied by the cosine of the inclination angle. A pack inside a Lamella Plate Settler holds dozens of plates stacked only a few centimetres apart, so those projections add together. The equivalent settling area of a Lamella Plate Settler commonly reaches ten to thirty times the plan area the unit actually occupies.

The second effect is distance. In an open basin a particle may have to fall two or three metres before it is safe from the outgoing flow. Inside a Lamella Plate Settler it falls only the clear spacing between two plates, typically fifty to one hundred millimetres, so a process that would take hours is finished in minutes.

These two effects show up directly in the design figures. Referred to the projected plate area the rise rate inside a Lamella Plate Settler is held low, which is what makes the separation dependable. Referred to the plan area of the equipment the same duty corresponds to roughly four to ten m³ per m² per hour, several times what a horizontal flow basin can sustain on the same ground.

3. Modular Pack Design for Flexible Build and Retrofit

The settling area of a Lamella Plate Settler is delivered as discrete packs rather than as one welded assembly. Each pack is a bolt together module of standard width and height, dimensioned so that shipping stays within normal container limits and so that handling on site needs only light lifting equipment.

Modular construction is what makes the settling area of a Lamella Plate Settler adjustable rather than fixed. Typical arrangements include the following.

· Packs sized to standard container widths for economical shipping

· Additional packs added to the same tank to raise capacity in defined steps

· Parallel units sharing one inlet distribution channel and one sludge header

· Packs inserted into an existing concrete basin to uprate a working plant

· Individual packs lifted out for washing without draining the complete unit

· Flat plate or hexagonal tube modules selected according to the solids

· Pack material chosen from PVC, polypropylene, stainless steel or FRP

The retrofit case deserves particular attention. An existing rectangular sedimentation tank that has reached its hydraulic limit can often be brought back into service simply by fitting packs from a Lamella Plate Settler into the clarification zone, which avoids new civil works and keeps the plant layout untouched.

4. Higher Treatment Capacity From a Given Footprint

Because throughput is governed by projected settling area, and because that area is supplied in modules, the capacity of a Lamella Plate Settler scales almost linearly with the number of packs installed. Capacity planning therefore becomes a matter of counting modules rather than of resizing a structure.

Our standard Lamella Plate Settler range covers one to one hundred and fifty m³ per hour in a single unit, and larger duties are met by operating units in parallel from a common distribution channel. With suitable coagulation and flocculation ahead of the inlet, a Lamella Plate Settler commonly removes eighty five to ninety five percent of the suspended solids presented to it.

Where a Lamella Plate Settler is used to uprate an existing basin, the throughput of that basin can typically be raised by a factor of two to four without enlarging the structure, because the packs supply settling area that the empty tank simply did not have.

Actual capacity always depends on particle density and size, on water temperature and viscosity, and on the strength of the floc produced by the chemical stage. For this reason we confirm the rise rate for each Lamella Plate Settler against measured water data before the equipment is dimensioned.

A Lamella Plate Settler suits any stream carrying settleable or chemically conditioned solids where clarification has to be achieved inside a limited area. The sectors below are representative.

Coal Preparation and Washing Plants

Coal washing circuits carry fine coal, clay and shale particles that remain in suspension for a long time and quickly silt up thickeners and settling ponds.

A Lamella Plate Settler on the circuit clarifies wash water for return to the plant and produces a thickened underflow that can be sent straight to a filter press, which closes the water balance and cuts make up demand.

Concrete Batching and Precast Plants

Truck washout and aggregate rinsing at a batching plant generate highly alkaline water loaded with cement fines that set hard in any vessel where they are allowed to rest.

Since the pack of a Lamella Plate Settler is self cleaning under gravity and can be lifted out for washing, the unit copes with this duty and returns recovered water to the mixing or wash cycle.

Stone Cutting and Ceramic Polishing

Sawing, grinding and polishing of stone, tile and sanitary ware release very fine mineral powder that gives the process water a persistent milky appearance.

With flocculant dosed ahead of the inlet, a Lamella Plate Settler drops this powder out of suspension so the water can be recirculated to the saws and polishing heads, while the settled slurry is drawn from the hopper for dewatering.

Automotive and General Paint Shops

Spray booth water curtains and pretreatment lines collect paint overspray, phosphate sludge and detackified resin solids that are light, sticky and difficult to settle in an open tank.

The gentle laminar path inside a Lamella Plate Settler keeps conditioned floc intact until it reaches a plate surface, which gives a clearer overflow for reuse in the booth and a concentrated sludge for disposal.

Lithium Battery Material Production

Manufacture of cathode and precursor materials generates wash and reaction waters containing metal hydroxide and carbonate precipitates together with a high dissolved salt load.

A Lamella Plate Settler in the pretreatment train separates these precipitates ahead of evaporation or membrane recovery, protecting the downstream equipment and improving the quality of the recovered salt or water.

Semiconductor and Photovoltaic Polishing

Wafer sawing, lapping and chemical mechanical polishing produce water carrying silicon and abrasive fines at very small particle size and comparatively low concentration.

After coagulation these fines form a fragile floc, and the low shear conditions inside a Lamella Plate Settler allow that floc to be captured rather than broken up, which is what makes reuse of polishing water practical.

Tannery and Leather Processing

Beamhouse and tanning operations discharge water containing hair, fat, lime solids and chrome bearing sludge, a mixture that blinds screens and overloads biological stages.

Used after primary screening and chemical conditioning, a Lamella Plate Settler removes the settleable fraction and lowers the solids and organic load carried forward to the biological plant.

Get a Quote

Send us your water data and we will return a Lamella Plate Settler proposal covering equipment sizing, a general arrangement sketch, a budget price and a delivery time.

The following details allow us to size a Lamella Plate Settler correctly.

· Average flow and peak flow to be clarified

· Suspended solids at the inlet and the value required at the outlet

· Whether the solids are mineral, metallic, fibrous, biological or chemically precipitated

· Approximate particle size and whether the solids are abrasive

· Temperature, pH and chloride level of the water

· Coagulant and flocculant already in use, if any

· How the sludge will be dewatered or disposed of

· Plan area and height available, indoor or outdoor

· Material preference and any coating specification

· Delivery port, required certificates and target schedule

With this information our engineering team can confirm the pack area, the number of modules and the model of Lamella Plate Settler that matches your duty.

Write to us with your project details and we will reply with a technical proposal and pricing.

winnie@yihuaep.com