Sulfamic Acid in Mining and Mineral Processing

Sulfamic acid (H₃NSO₃, CAS 5329-14-6) is a solid, easy-to-handle acid that mineral-processing and metal-production plants use for cleaning and descaling – jobs where a liquid mineral acid such as hydrochloric acid would be harder to transport, store and control. This article looks at where it is used in mining, how it is applied, and why it is often preferred over liquid acids on site.

1. What makes sulfamic acid useful on a plant

Property	Why it matters on site
Solid at room temperature	Easy and safe to ship, store and dose – no fuming liquid acid
Highly water-soluble	Makes up quickly to the working strength when and where it is needed
Chloride-free	Does not attack stainless steel the way hydrochloric acid can
Controllable strength	The cleaning solution is prepared on site, so strength and time are controlled

2. Where it is used

Application	Job
Descaling process equipment	Removes carbonate and hydroxide scale from pipelines, pumps, tanks, heat exchangers and evaporators
Evaporator and crystalliser cleaning	Cleans scale in salt, potash and brine circuits, including lithium-brine plants
Pickling and rust removal	Removes oxide and rust from steelwork, structures and equipment
General plant cleaning	Removes mineral scale before maintenance or return to service

These are cleaning and maintenance jobs, not a reagent in the flotation or leaching circuit itself – but they are constant, recurring needs that make sulfamic acid a standard stock item for a plant.

3. How descaling is done

Parameter	Typical practice
Solution strength	About 5 – 10% sulfamic acid in water
Temperature	About 40 – 80 deg C (warmer cleans faster)
Contact time	Set by the scale thickness; circulate and monitor
Method	Circulate or soak, then rinse thoroughly

Before cleaning, confirm the compatibility of the equipment materials – not every metal or alloy suits every acid. After cleaning, rinse thoroughly and neutralise/dispose of the spent solution according to site rules.

4. Why not just use hydrochloric acid?

Factor	Sulfamic acid	Hydrochloric acid
Form	Solid; dissolves on site	Liquid; fuming and corrosive
Transport and storage	Straightforward	Requires corrosion-resistant containment and controls
Effect on stainless steel	Chloride-free – much lower pitting risk	Chlorides can cause pitting and stress-corrosion cracking
Handling hazard	Lower	Higher

Where equipment is stainless steel or contains sensitive alloys, the chloride-free nature of sulfamic acid is the deciding factor – it removes the scale without introducing the chlorides that cause pitting. Where a plant stores and ships chemicals to a remote site, the solid form is also far easier to manage.

5. Safety and handling

Do not mix with nitrites. Sulfamic acid reacts with nitrites to release nitrogen gas and heat – keep the two chemicals strictly separate.
PPE and ventilation. It is acidic and irritant; use goggles, gloves and good ventilation.
Storage. Keep dry and sealed, away from alkalis, nitrites and strong oxidisers.
Documentation. Follow the SDS for handling, first aid and transport.

6. Grades, packaging and supply

Item	Detail
Purity	Typically 99.5% min; food / technical grades available
Packaging	25 kg PP/PE bags; 1000 kg jumbo bags; full container loads
Documents	Per-batch COA and SDS; third-party inspection on request
Delivery	FOB or CIF to African ports including Durban, Mombasa, Dar es Salaam, Tema/Takoradi, Lagos/Apapa and Beira

Sulfamic acid is a commodity acid, and price and reliable supply matter as much as purity. As a large-scale producer we offer competitive pricing on bulk volumes with consistent quality – give us your annual tonnage and discharge port for the best terms.

Frequently Asked Questions

Is sulfamic acid used in mining?

Yes – for descaling and cleaning process equipment (pipelines, pumps, heat exchangers, evaporators and crystallisers) and for pickling and rust removal, where a solid, chloride-free acid is preferred over hydrochloric acid.

Can sulfamic acid clean stainless-steel equipment?

It is chloride-free, so it is much gentler on stainless steel than hydrochloric acid, which can cause pitting and stress-corrosion cracking. Always confirm compatibility with the specific alloy and scale first.

What strength is used for descaling?

Typically about 5-10% in water at about 40-80 deg C; the exact strength and time depend on the scale.

Do you supply sulfamic acid to African mining sites?

Yes – 25 kg bags and 1000 kg jumbo bags, FOB or CIF to Durban, Mombasa, Dar es Salaam, Tema/Takoradi, Lagos/Apapa, Beira and other ports, with per-batch COA and SDS and competitive bulk pricing.