Can you provide free samples and technical support for a mill trial?

Yes — this should be the starting point of a serious FAS development program.

A professional supplier should be able to provide:

Step 1 — Free Sample

Typical sample:

1–5 kg FAS

for laboratory evaluation.

Step 2 — Laboratory Trial

Test:

Control

Existing Sodium Hydrosulfite

FAS

Different FAS dosages

Different pH conditions

Optional FAS + H₂O₂ sequence

Step 3 — Data Analysis

Compare:

ISO Brightness

Δ Brightness

Color reduction

Brightness stability

Pulp strength

Chemical consumption

Chemical cost / ADT

Step 4 — Mill Trial

After laboratory optimization:

FAS → mill-scale trial → production data → cost calculation

Step 5 — Commercial Qualification

If the results meet the customer's requirements:

Supplier Qualification → Regular Purchase → Long-Term Supply

Recommended FAS Trial Matrix

For a first laboratory screening, the following matrix can be used as a starting point:

Note: These conditions are intended for screening and should be optimized according to the actual pulp furnish and mill process.

What We Recommend Measuring

A meaningful FAS evaluation should include at least:

Optical Properties

ISO Brightness

L*

a*

b*

Whiteness

Yellowness

Pulp Properties

Freeness

Ash

Tensile strength

Tear strength

Burst strength

Process Parameters

FAS consumption

NaOH consumption

Temperature

pH

Reaction time

Pulp consistency

Environmental Parameters

COD

Sulfur-related wastewater parameters

Effluent pH

Other mill-specific parameters