Ferrous Sulphate Manufacturing Plant Project Report (DPR) 2026

What is ferrous sulphate?

Ferrous sulphate, or iron(II) sulphate, is a pale green iron salt sold mainly as the heptahydrate (FeSO4·7H2O), known as copperas or green vitriol, with about 20% iron, and as the dried monohydrate (FeSO4·H2O), with about 30% iron in commercial grades. Most tonnage does not begin as a purpose-made chemical. It leaves titanium dioxide plants and steel pickling lines as a co-product, and processors then dry, purify or granulate it for sale.

The Harmonized System classifies the product under HS 2833.29, other sulphates, a basket subheading that also covers other metal sulphates. National lines separate it, such as the U.S. tariff line 2833.29.20 for sulphates of iron. Water utilities use it as a coagulant and phosphate remover, cement makers use it to reduce hexavalent chromium, and farmers apply it to correct iron deficiency and control moss in turf. Feed premix makers, pigment producers and pharmaceutical firms buy higher-purity grades, and lithium iron phosphate cathode chains now use it as an iron source.

Ferrous sulphate market overview and global demand

Credence Research does not publish a dedicated report on this product, and this page does not state a USD market size for it. Physical indicators give a clearer picture. A 2026 review in RSC's EES Batteries puts by-product generation from sulfate-route titanium dioxide at up to about 6 million tonnes a year, against about 12 million tonnes of total global capacity, with water treatment taking about 30% of the market and a price near USD 100 per tonne.

Titanium dioxide therefore sets much of the supply. The USGS estimates world pigment capacity at 9.9 million tonnes at year-end 2025, including 6 million tonnes in China, or about 61%. The global titanium dioxide market was about USD 25.4 billion in 2025, based on Credence Research's USD 23.8 billion for 2024 and 6.9% CAGR. The pigment industry's drift toward the chloride route, which yields no ferrous sulphate, threatens long-term supply.

Demand spreads across regions and uses. Europe and North America buy coagulants, a segment within the water treatment chemicals market, which Credence Research values at USD 34.25 billion for 2024. Asian and Latin American growers buy iron micronutrients, and the WHO essential medicines list has included ferrous salt with folic acid since 1982.

Battery demand changed pricing in 2026. Chinese trade data show the Chinese price rising from 650 to 760 yuan per tonne between December 2025 and January 2026 as pigment output fell, followed by a sharp second-quarter surge and a pullback. Merchant processors now compete with iron phosphate plants for the same crystals.

Ferrous sulphate manufacturing process

The commercial route for a merchant plant is upgrading, not synthesis. Copperas from pigment plants and iron-rich spent pickling liquor from steel mills arrive cheaply because generators must otherwise treat or dispose of them. Dissolving scrap iron in fresh sulphuric acid also works and suits pharmaceutical and food grades, where a clean feed matters, but it rarely competes on bulk prices. One tonne of heptahydrate holds about 0.20 tonnes of iron and needs about 0.35 tonnes of sulphuric acid before losses.

• Feedstock receiving. Each lot is tested for iron, free acid, titanium, manganese and heavy metals, because contaminants decide which grade the plant can sell.
• Dissolving and reduction. Crystals or liquor go to acid-resistant tanks. Operators add scrap iron to neutralize free acid and reduce ferric iron back to the ferrous state.
• Filtration. Filter presses remove insoluble residues, and purified grades get extra polishing or sulfide treatment to lower lead, arsenic and cadmium.
• Crystallization. Cooling crystallizers drop heptahydrate from the clarified liquor, and centrifuges separate crystals from mother liquor, which returns to the dissolver with a bleed to effluent treatment.
• Drying. Flash, rotary or fluid bed dryers drive off about 0.64 tonnes of water per tonne of monohydrate. Staged heating matters, because heptahydrate melts in its own crystal water near 64°C and can foul dryer walls, while overheating or excess air oxidizes iron to the ferric form.
• Milling and packing. Product is milled or granulated, screened and packed in 25 kg bags or bulk bags. Fertilizer buyers often prefer dust-free granules, and feed buyers specify fine powder.

Bulk water treatment sales can skip purification and drying altogether, so the plant's grade mix sets both its capital needs and its margin.

Ferrous sulphate plant setup cost

The indicative build is a 30,000 tonne a year monohydrate plant, or 100 tonnes a day over 300 days, on about 3 acres of serviced land. Fixed CapEx comes to about USD 3–5 million at an Asian chemical park and an assumed USD 7–12 million at a U.S. or EU site, where civil works, fabrication and permitting cost more. No disclosed plant gives both cost and tonnage, so this is a bottom-up estimate on assumed costs. Working capital of about USD 0.5–0.8 million is excluded, and the full report can be recast for any country.

Land shows how each row was built. At an assumed USD 40–55 per square meter, in line with chemical park allotment rates in western India, a 12,000 square meter plot costs about USD 500,000–640,000, or about 15% of CapEx at the midpoint. Rural U.S. land may cost less, and EU chemical parks often cost more, so this share moves widely by location.

Published design studies show why the scope matters. Indonesian university pre-designs for 20,000–25,000 tonne a year heptahydrate plants report fixed capital of about Rp 434–485 billion, or about USD 30–33 million, for full reactor trains on factored costs. Those studies imply profit far above current market prices, so they serve only as a ceiling, not as the base for this estimate.

At the base case, feedstock is about 60–68% of cash cost, and dryer fuel is the next largest item. Each USD 10 per tonne change in copperas cost moves cash cost by about USD 16 per tonne of monohydrate.