FLOPAM AN 970 VLM Equivalent: High-Charge Very-Low-MW Anionic PAM Supply Route

The SNF FLOPAM powder catalogue 2007, page 43, records AN 970 VLM as an anionic powder at High charge and Very Low molecular weight. It gives approximate Brookfield viscosities of 700, 350 and 120 cps at preparation concentrations of 5.0, 2.5 and 1.0 g/L respectively, a recommended preparation of 8 g/L with a maximum of 15 g/L, and a dissolution time of 45 minutes, all under SNF catalogue test conditions. Those conditions are the SNF protocol and are not the same as ChinaPAM's preparation window.

These are historical indicative values for a catalogue reference product. They appear here once because a buyer specifying AN 970 VLM needs to know what attributes the original selection was based on. They are not presented as current SNF specifications and they do not carry over as ChinaPAM parameters. The preparation conditions in particular differ: the SNF catalogue used 8 g/L and 45 minutes; our window is 1–3 g/L recommended and 60 minutes, which are different protocols producing different dissolved polymer concentrations per litre.

CNfloc 1063 is the charge-nearest route. It sits at High charge and Medium MW on the ChinaPAM scale. The charge match is close — both the incumbent and the 1063 route sit in the High anionic charge band on their respective scales — but Medium MW is above Very Low MW, which means the dissolved polymer has a longer chain and a higher solution viscosity at the same mass concentration. The practical question for the 1063 route is whether the duty can tolerate a somewhat longer chain, or whether Very Low MW was essential — for example, to reduce solution viscosity at a high make-up concentration or to achieve fast floc formation in a fast-flow clarifier.

1090-FG is the MW-nearest route. It sits at Low MW and Very High charge on the ChinaPAM scale. Low MW is closer to Very Low MW than Medium MW is, so the chain-length behaviour is nearer to the incumbent. The charge density is higher — Very High versus High — which means over-conditioning is the risk to test for. A clarification circuit that was running AN 970 VLM at a well-tuned dose may restabilise if very-high-charge polymer is introduced at the same dose without adjustment.

The first is dropping the VLM suffix and sourcing a standard-MW anionic grade as the alternative. Standard or high-MW grades behave fundamentally differently in fast-mixing clarifiers, high-dose dewatering and low-viscosity make-up applications. The VLM designation was the basis of the original selection, and it stays as the selection criterion here.

The second is hiding the MW/charge trade-off by presenting only one route. If a buyer receives only the charge-nearest route without being told that the MW band is higher, or only the MW-nearest route without being told that the charge band is higher, the trial fails for the wrong reason. Both routes have disclosed descriptor gaps. The trial result, not the catalogue alignment, is the evidence that matters.

To open the enquiry, send the full grade string including the VLM suffix — a bag-label photograph is ideal — along with the application duty (clarification, dewatering, effluent treatment), the water or sludge chemistry you can share, the current dose expressed as grams per cubic metre or kilograms per tonne dry solids, and the make-up concentration and mixing time your unit runs at.

What comes back is a quotation for both screening routes, the applicable product documents, sample quantities for bench work, and a written test plan naming the two routes, the dose points and the process metrics. We review the results with you and confirm the commercial grade, dose and delivery terms for volume supply. The commercial side — price, sample, documents — does not wait on the process data.