PAM Evaluation Scenarios

The Problem Buyers Bring Us

Municipal plants running belt presses or decanter centrifuges usually ask two questions before changing polymer: which cationic charge density matches their sludge, and what dosage per ton of dry solids to budget. Cake dryness, filtrate clarity and polymer consumption all move together, so a grade cannot be chosen from a catalogue line alone.

What We Need From You

• Sludge type and origin: primary, secondary, mixed or digested
• Dry solids content of feed sludge (%) and daily tonnage of dry solids
• Dewatering equipment: belt press, decanter centrifuge, screw press or filter press
• pH, temperature and conductivity of the sludge
• Current polymer type, dosage per ton dry solids and achieved cake dryness
• Target cake dryness and any discharge or disposal limit you must meet

How the Screening Runs

• We propose a shortlist of cationic grades across a charge-density range rather than one grade, because digested and secondary sludges respond differently.
• You receive free samples of the shortlisted grades for jar testing, or send us a fresh sludge sample and our lab runs the screening.
• Each grade is made up as a 0.1-0.5% stock solution, dosed across a bracketing series, and flocculated under the mixing intensity your machine applies.
• The two or three grades with the best floc strength and water release move to a plant-scale trial on one shift before any bulk order.

What Gets Measured

• Capillary suction time or drainage time at each dosage step
• Cake dry-solids content after pressing (%)
• Filtrate or centrate suspended solids and visual clarity
• Polymer consumption in kg per ton of dry solids at the working dosage
• Floc shear resistance after recirculation through the feed pump

Pass / Fail Criteria

• Cake dryness at least equal to your current polymer at the same or lower dosage
• Filtrate clarity no worse than the baseline you record before the trial
• A stable dosage window, so that a small dosing error does not collapse the floc
• Repeatable results across at least two sludge samples taken on different days

Documents You Receive

TDS for each shortlisted grade, SDS, COA for the batch supplied, and a written jar-test record with the dosage series and measured values.

The Problem Buyers Bring Us

Thickener performance is set by slurry chemistry as much as by polymer. High-pH circuits, cyanide-containing gold circuits and high-salinity process water each rule out different flocculants. Selecting on molecular weight alone usually produces fast initial settling with weak flocs that break in the rake or recirculation line.

What We Need From You

• Ore type and the mineral being recovered
• Slurry solids content (%) and tonnes per hour through the thickener
• Process water chemistry: pH, conductivity or TDS, and any cyanide or reagent carry-over
• Particle size distribution, especially the fines fraction
• Thickener or clarifier type, diameter and current underflow density
• Current flocculant, dosage in g per tonne of ore, and your water-recovery target

How the Screening Runs

• We match ionicity to your slurry chemistry first: nonionic grades where high pH or reagent interference rules out anionic charge, anionic grades where the slurry tolerates them.
• Settling tests run in graduated cylinders on your own slurry at a dilute polymer concentration, typically 0.05-0.1%, with a dosage series on each candidate.
• Settling rate and supernatant turbidity are recorded for every dosage step so the dosage window, not just the best single point, becomes visible.
• Shortlisted grades then run a shear-recovery check: flocs are formed, sheared, and allowed to resettle to see which survive the rake and pump path.

What Gets Measured

• Initial settling rate in m/h at each dosage
• Supernatant turbidity in NTU and suspended solids
• Compacted bed solids content after a fixed settling time
• Dosage in grams per tonne of ore at the working point
• Settling rate retained after a controlled shear step

Pass / Fail Criteria

• Underflow density and overflow clarity both at least matching your current baseline
• Dosage no higher than your current flocculant for the same clarity
• Flocs that resettle after shear rather than dispersing permanently
• Stable performance on slurry samples from at least two different production periods

Documents You Receive

TDS and SDS per grade, COA for the supplied batch, settling-test record with the dosage series, and a written note of which ionicity was ruled out and why.

The Problem Buyers Bring Us

Polymer flooding candidates fail on salinity and temperature, not on fresh-water viscosity. A grade that looks strong in tap water can lose most of its viscosity in formation brine at reservoir temperature, and shear through the injection string degrades it further. Screening has to reproduce those three stresses before any field commitment.

What We Need From You

• Formation water analysis: total dissolved solids, divalent cation content and pH
• Reservoir temperature and injection temperature
• Target injection viscosity in cP and the shear rate it is specified at
• Reservoir permeability and the injection-string configuration
• Water cut, well spacing and the injection rate you plan to run
• Required aging period before the polymer must still meet the viscosity spec

How the Screening Runs

• We prepare candidate PHPA and salt-tolerant grades in your supplied brine, not in deionised water, since brine is where the difference appears.
• Viscosity is measured on a rotational viscometer at a stated shear rate and at reservoir temperature, with the concentration bracketed around your target.
• Samples are aged in sealed anaerobic containers at reservoir temperature, then re-measured so viscosity retention over time is a recorded number.
• A filtration-ratio and shear-degradation check screens out grades that would plug the formation or break down in the injection string.

What Gets Measured

• Apparent viscosity in cP at stated polymer concentration, shear rate and temperature
• Viscosity retention (%) after each aging interval in your brine
• Filtration ratio as an injectivity indicator
• Viscosity loss across a controlled shear step
• Dissolution time to a homogeneous, fisheye-free solution

Pass / Fail Criteria

• Target viscosity met in your own brine at reservoir temperature, not in fresh water
• Viscosity retention through the aging period you specify, with the measured values written down
• Filtration ratio within the limit your injectivity requirement sets
• Reproducible results on a second sample of the same brine before any bulk order

Documents You Receive

TDS and SDS, COA for the supplied batch, and a brine-specific viscosity and aging record stating concentration, shear rate, temperature and each measured value.

The Problem Buyers Bring Us

Mills often need two different polymers at once: a cationic retention aid dosed at the wet end, and an anionic flocculant on the effluent after coagulation. The wet-end choice interacts with filler, furnish and white-water chemistry, so a retention aid that works on virgin furnish may not work on recycled stock.

What We Need From You

• Paper grade produced and furnish composition, including recycled content
• Machine speed, daily tonnage and headbox consistency
• Current first-pass retention and how it is measured
• White-water turbidity, conductivity, pH and temperature
• Effluent flow, suspended solids and COD, plus your discharge limits
• Existing coagulant programme such as PAC or alum, and its dosage

How the Screening Runs

• The wet end and the effluent are screened as two separate programmes, because one polymer rarely serves both well.
• Retention candidates are evaluated on your own furnish using a drainage and retention test at the consistency and shear your headbox runs.
• Effluent candidates are jar-tested after your existing coagulant, with the anionic grade dosed in a bracketing series at a dilute working solution.
• Promising pairs then run a short machine trial on one grade and one shift, with white-water and effluent sampled before and during the trial.

What Gets Measured

• First-pass retention (%) and drainage time on your furnish
• White-water turbidity and consistency at the working dosage
• Effluent suspended solids and turbidity after settling
• Retention-aid dosage in kg per tonne of paper, and effluent dosage in mg/L
• Floc appearance and whether it survives the pressure screen

Pass / Fail Criteria

• Retention at least matching your current baseline without a sheet-formation penalty
• Effluent suspended solids within your permit limit with margin, measured not estimated
• No increase in deposits or dosing-system blockage over the trial shift
• Both programmes stable when furnish or recycled content shifts within your normal range

Documents You Receive

TDS and SDS for both the retention aid and the anionic grade, COA per batch, drainage and jar-test records, and a dosing-point recommendation for the wet end and the effluent line.

The Problem Buyers Bring Us

Coal fines circuits punish weak flocs. A very high molecular weight grade can settle quickly in a cylinder test and still fail in the plant, because the flocs break in the recirculation loop and the fines report to tailings anyway. Medium molecular weight with the right charge often holds up better, which is exactly what a trial has to establish.

What We Need From You

• Raw coal throughput in tonnes per hour and the fines fraction
• Thickener or filter type, and whether a filter press or belt filter follows
• Slurry solids content, pH and process water conductivity
• Clay or ash content, which drives how much polymer the surface demands
• Current flocculant, its dosage in g per tonne, and where fines are being lost
• Water-recovery target and whether the circuit runs closed loop

How the Screening Runs

• Candidates span a molecular-weight and charge-density range rather than only the highest molecular weight available.
• Settling tests run on your slurry with a dosage series for each grade at a dilute make-up concentration.
• Every shortlisted grade goes through a shear step that mimics the recirculation path, then resettles, so floc durability is measured rather than assumed.
• If a filter follows the thickener, filtration rate and cake moisture are checked on the shortlisted grades before a plant trial.

What Gets Measured

• Settling rate in m/h and supernatant turbidity at each dosage
• Underflow or bed solids content after a fixed time
• Settling rate retained after the shear step
• Filtration rate and cake moisture (%) where a filter is in circuit
• Working dosage in grams per tonne of feed

Pass / Fail Criteria

• Overflow clarity and underflow density at least matching your current baseline
• Flocs that survive the shear step and resettle at a usable rate
• Dosage no higher than your current product for equal clarity
• Consistent behaviour across slurry samples with different ash or clay content

Documents You Receive

TDS and SDS per grade, COA for the supplied batch, settling and shear-recovery records with the dosage series, and filtration data where a filter is in circuit.