Improving flocculation and dewatering performance of iron …
At high flocculant dosage (20 g/t), the settling rate increases from 0.8 to 2.9 cm/s by increasing the slurry pH from 4 to 12. ... Slurry pH of thickeners feed before and after NaOH addition (flocculant: 8 g/t). ... At present, the flocculant is prepared in three 4.7 m 3 preparation tanks as a 0.5% solution and pumped to the tailings thickeners ...
McLanahan on the five tests for thickener selection
These five tests include particle size analysis, cylinder test and chemical screening, static settling, dynamic settling and yield stress. Since the settling rate is heavily influenced by the particle size, the first …
Modelling the impact of two different flocculants on the
The performance of the flocculant BASF Rheomax® DR 1050 has been previously compared to a conventional anionic flocculant in turbulent pipe flocculation of mineral suspension, suggesting that the ...
Recent developments in techniques and methodologies for …
The cause of unusually high thickener overflow solids can be easily resolved using a video/magnification system to measure the ... flocculant is introduced into a pipe through which the feed suspension flows at a set rate, and aggregate 'size' measurements are made downstream using the FBRM probe in order to determine the rate at which the ...
Flocculants and tailings – Process productivity
The introduction of synthetic, high molecular weight, water-soluble polymer flocculants was a turning point in tailings dewatering within the minerals industry. Gravity thickening had previously relied on coagulants and natural products (e.g. starch) to aggregate particles and accelerate settling. Synthetic flocculants enable much larger ...
Flocculant Dilution System in Thickener Feed well
Flocculant Dilution System in Thickener Feed well. In order to maximise the benefits obtained from flocculating agents when used as settling aids in high rate and conventional thickeners, it is often necessary to dilute the thickener feed prior to flocculant addition. In some cases, no flocculation at all is possible unless dilution water …
MIP Process Corporation USA | Products & Servicves | Thickeners …
During thickener operation, feed enters the feedwell, via a feed pipe or open launder. In order to promote settling, it is increasing to dissipate this energy. In some cases, flocculants or coagulants are added to the feed to agglomerate particles and improve settling. Feed dilution may also take place.
HigH Rate tHickeneRs
The key advantages of a High Rate Thickener over a conventional thickener are as follows: Some of key features of the MBE High Rate Thickener are • The HRT is designed specificallyto operate with flocculantsand hence optimises flocculant consumption. • The HRT has a special " McTurbo" feed well design combined with automatic feed
Vane feedwell flocculant sparger optimisation trial | Request …
The flocculant addition point (or points) can be used as a tuning method to alter the effective flocculation time in a feedwell, with addition further up the feed pipe increasing the residence ...
ANDRITZ thickening and clarification systems
This is why ANDRITZ has put decades of expertise into thickening and clarification systems to provide an efficient and cost-effective solution. 20m in diameter coal high rate thickener. 35m in diameter Pb/Zn tailings - High rate bolted thickener. ANDRITZ thickening and clarification solutions are designed to achieve the highest production rates ...
McLanahan | High-Rate Thickeners
3:33. High-Rate Thickeners separate liquids from solids using hindered settling. Rotating rake arms collect settled sludge and move it toward the center discharge cone. They use minimal amounts of polymers/chemicals to drop the solids, making High-Rate Thickeners environmentally friendly. Thickeners are operated and controlled by a touch-screen ...
Tailings Thickener Improvements at Sentinel Copper Mine
High flocculant dosages (>60 g/t flocculant with the dosing pumps running at ) had no effect under these conditions: recovery often required a reduction in the feed rate. Laboratory testwork quickly identified the sensitivity of the settling rate to changes in feedwell solids levels (Figure 3).
The effect of flocculant solution transport and
In each case, the feedwell is 6.0 m in diameter with 3 m of side-wall below the liquor surface and the feed inlet is 0.6 m in diameter, centred at 1.5 m below the liquor surface.For Case 2, the shelf is located 0.1 m below the base of the feed inlet.The model thickener has a diameter of 40 m, side-wall height of 5 m and is fed at 2000 m 3 h − 1.
The impact of achieving a higher aggregate density on …
Fig. 2 a shows the inlet configuration where the flocculant and feed flows join together. In this case the flocculant pipe has an ID of 3.0 mm; this dimension has been varied for experiments in which the flocculant concentration effects were examined and attempts were made to isolate the contribution from the corresponding changes in …
Constrained model predictive control of an industrial high-rate thickener
High-rate thickeners are used in the mining industry to improve water recovery from slurries and increase their solids ratio. High-rate thickeners operate under strict constraints and several disturbances. ... the feed slurry and the flocculant flow rates as the manipulated inputs, the feed slurry density, the circulation and the outlet flow ...
Mineral processing: Introducing 'next generation' feedwells
Development of flocculants in the early 1960's started a revolution in thickener design and operation eventually leading to the start of high rate thickening in the late 1960's. These thickeners are characterised by a feedwell with a bottom plate to deflect the flocculated feed horizontally into a preformed flocculated bed.
Advances in Thickener Flocculant Delivery
Feed slurries are typically flocculated in a thickener's feedwell to increase the settling rate, underflow density and overflow clarity. High molecular weight polymeric flocculants are normally used, but present a number of challenges in terms of make up, dilution, delivery and mixing with the feed slurry.Various aspects of the flocculant dilution and delivery …
Gravity Thickening
Static thickening tests will be conducted on each distinct sample. The effect of feed solids concentration, flocculant dosage, underflow density and other controllable physical parameters (within flowsheet constraints) will be examined. Compression zone data, important in high rate thickener sizing, is also gleaned from static tests.
High Rate Thickeners | Dewatering Plant
HIGH RATE TECHNOLOGY. Our specialised feedwell design allows for improved sediment discharge directed at the thickener apex, thus decreasing short circuiting and competing of solids particles with each other, leading to a faster settling rate of the material. Clarified Overflow. Electric & Hydraulic Drive Options. Bed Level & Density Control.
Thickener parts
The feed system comprises a critical set of components that have a significant impact on the overall thickener performance by ensuring the feed material is properly conditioned before being introduced to the …
Creative Engineers | High Rate Thickener
The feed well of the Hi-rate Thickener Contains a special Flocculation Chamber & the feed enters this Chamber a hollow Drive shaft. Creative High Rate Thickener can be used in variety of different applications – …
McLanahan | The 5 Tests Needed for Thickener Selection
The settling rate provides some insight into the size of Thickener needed, and the compaction indicates what the underflow density might look like. Dynamic settling. The dynamic settling test is used to simulate how a Thickener will perform based on real-time feed and flocculant dosing. Yield stress
Jar Testing | Laboratory Services
Adding a fine sand, or some other seed particle, and a flocculant to a feed slurry produces a ballasted floc. Mixing the slurry with coagulants/polymers and the ballasted floc sand causes the smaller particles attached to the sand to produce larger, heavier particles that settle quickly and leave a clearer supernatant.
Expert Control Tuning of an Industrial Thickener
The thickener is 150 m diameter and was designed to process 13000 m3/h of pulp, containing 27% of solids, with a specific gravity of 1.2, to deliver an underflow with a 54% of solids. The flocculants is added at a rate of 15g/ton of pulp or about 270 m3/h of a solution with a low flocculants concentration (0.02%).
Feedwell upgrade cuts flocculant consumption and water …
"The design of the mixing trough and position of the flocculant pipe, feed pipe, and nozzle each had to be specifically designed to generate the necessary conditions for the feedwell to operate efficiently," added King. ... High-rate Thickener. High-density Thickener. Keep exploring. Stories from FL. News. 29 June 2024. Presentation ...
High Rate Thickeners
The mixed feed then flows to the settling chamber. Since the solids are fully flocculated, there is no retention time demand, and since the floe structure is well-formed, it has a high settling rate. This design, …
Flocculation, dewatering and sedimentation behaviour of …
An 18 m-diameter Deep Bed™ paste thickener at paste disposal facility (feed volume/rate is 288 t/h) • A 90 m-diameter primary Titan™ traction thickener is situated at the main plant (feed volume/rate is 18000 m 3 /h) [30], [31] Western Australia Iron Mine (Anonymous) Australia • Decrease flocculant usage > 16 wt% •
Most common problems in thickener operations (part 1)
Thickener area. The thickener area depends on the mineral sedimentation rate (m2/t/d) or the specific feed rate (t/h/m2) which are determined by laboratory or pilot testing. These tests are carried out with representative samples of mineral and different granulometry. The tests also evaluate different dosages of flocculant.
Conventional or High Capacity Thickeners
discharge rate. Higher feed rates to a given thick discharge is typically relatively small compared to particles up to the overflow. Only those particles ha velocity will possibly settle out. Hence, thickener overflow water clarity can be achieved. In general, thickener handling rate is expres area (GPMFt2) or cubic meters per hour per
Liquid–Solid Separation: De-Sanding—Flocculation, …
Flocculating at high solids concentrations generally requires high flocculant dosages and results in slow settling and poor overflow clarity. The optimal feed concentration depends on a number of factors including specific gravity and particle size, but by diluting the feed it may be possible to increase the flocculated settling rate by an ...