1. Architecture of a Brazilian integrated steel mill
An integrated steel mill starts from iron ore and coal, and ends in coils, plates or bars.
The standard integrated-route flow is: iron ore + fluxes → sintering (transforms into pellets); coal → coke oven (transforms into metallurgical coke); coke + sinter → blast furnace (produces liquid pig iron); pig iron → BOF steelmaking (oxygen blow, transforms into liquid steel); liquid steel → continuous casting (solidifies into slabs, billets or blooms); slabs → hot rolling (forms coils or heavy plates); coils → acid pickling + cold rolling (produces thin coils); thin coils → galvanizing (zinc protection).
Each of these stages has its own pump set with specific requirements.
The other route is semi-integrated, based on an electric arc furnace (EAF) that consumes ferrous scrap and reheats it by electric arc, dispensing with blast furnace and coke oven. Major Brazilian operators run several units in this model, as do regional mini-mills. The electric arc furnace also consumes large volumes of cooling water — electrodes, roof and dome water panels, auxiliary equipment — and has its own family of pumping points, although more compact than the fully integrated one.
2. Blast furnace and coke oven: the largest water consumers
The blast furnace is the single largest water consumer in an integrated mill. The cooling system covers multiple circuits: stave cooling (refractory walls with internal water tubes), hearth cooling (base of the furnace where pig iron and slag accumulate), tuyere cooling (hot air injection), charging bell cooling and gas cleaning system cooling.
Cumulative flows in a large blast furnace (4,000 to 5,000 m³ useful volume, typical of Brazilian integrated mills) easily exceed 10,000 m³/h of circulating water in closed or semi-closed circulation. This water is normally recirculated through cooling towers or heat exchangers, and chemistry is controlled to prevent stave scaling and corrosion.
For this application, FBCN is the standard pump. Typical models are FBCN 200-500 or 250-500 in parallel multi-unit configuration, cast iron with B62 bronze impeller for tower water, 1,750 rpm nominal rotation and 150 to 400 kW motorization per pump. Water chemistry needs treatment with corrosion inhibitor and biocide — the blast furnace in particular is sensitive to any water failure because a damaged stave can leak water into the furnace, causing steam explosion.
Pumping system reliability is therefore critical from an industrial safety standpoint.
The coke oven, in turn, has two main circuits: the coke quenching system that applies large volumes of water over incandescent coke leaving the oven, and the coke gas cleaning and refrigeration system. Both circuits have aggressive chemistry due to phenol, ammonia and cyanide entrainment from coal distillation, and the FBCN material recommendation is 316L at direct contact points with contaminated effluent, and cast iron in closed cooling circuits downstream of treatment.
3. BOF steelmaking and continuous casting
The oxygen steelmaking (LD or BOF) receives liquid pig iron from the blast furnace and blows pure oxygen over the metal mass through a water-cooled lance. This lance is one of the most critical pumping points of the system: it operates near the metal bath at 1650 °C, with continuous water flow and no failure tolerance.
The recommendation is redundant FBCN in pairs (main pump + automatic backup pump with startup in up to 10 seconds), continuous pressure and flow monitoring, and an electrical panel with own generation backup. Failure of lance cooling water causes it to melt in seconds and unplanned steelmaking shutdown, with losses of millions of reais per day.
Continuous casting is the stage where liquid steel solidifies into slabs, billets or blooms. There are two main cooling systems: the primary (water-cooled copper mold through which liquid steel passes and starts to solidify) and the secondary (water sprays applied directly over the already partially solidified slab or billet at mold exit). The primary mold requires very high-purity water (conductivity <5 μS/cm, no chlorides) to prevent copper galvanic corrosion, and the FBCN in this circuit is in 316L.
Secondary sprays use less demanding process water in cast iron or bronze.
4. Hot and cold rolling: sprays and emulsions
Hot rolling receives slabs or billets heated in a reheating furnace and reduces them by successive passes between work rolls, transforming them into coils, heavy plates or profiles.
The water system is dominated by descaling sprays (high pressure, 150 to 220 bar, to remove oxide scale from the surface), inter-stand cooling sprays (between rolling stands, to maintain controlled temperature) and the laminar flow table (controlled cooling of the finished product before coiling).
Descaling sprays are a specific application of multi-stage FBCN or alternative high-pressure pumps; inter-stand sprays and laminar flow are single-stage FBCN at high flow (500 to 3,000 m³/h) and moderate pressure.
Cold rolling is conceptually different: the rolls operate at ambient temperature and reduction is limited by material work-hardening. Cooling and lubrication of the roll-strip interface is done by water-oil emulsion (5 to 10% oil, 90 to 95% water), applied via sprays over the strip being rolled.
The emulsion system has three critical pumping points: main emulsion recirculation pump (FBCN in 316L or cast iron casing with bronze impeller, due to the moderately corrosive nature of aged emulsion), emulsion filter pump (points with fine metal solids detached from the strip), and pure oil makeup pump. Emulsion temperature is controlled by external heat exchanger and recirculation system.
5. Acid pickling and galvanizing: aggressive chemistry
Acid pickling is the surface cleaning stage of hot-rolled coil before cold rolling. The process uses hydrochloric (HCl) or sulfuric (H₂SO₄) acid at 15 to 20% concentrations in baths at temperatures of 60 to 85 °C, removing surface oxide scale.
Pickling bath recirculation pumps are a critical corrosion service: common materials (316L) do not resist hot HCl, and the recommendation is FBCN in special nickel-chromium alloys (C-22) or, alternatively, FBCN with vulcanized rubber or PTFE lining.
For very severe applications (HCl >18% at 80 °C), the only realistic option is plastic or ceramic pumps, a situation in which FB Bombas refers the customer to a specialized supplier (Iwaki, Munsch).
Hot-dip galvanizing immerses the coil in molten zinc bath at 450 °C, protecting the surface against corrosion. The auxiliary system includes the coil heating furnace before immersion (frequently by thermal oil — FBOT territory), the cooling system after immersion, and the flow recirculation pumps at the bath side.
The FBOT application in this context is one of the clearest for the line: the thermal oil loop operates at 280-320 °C at moderate pressure, transferring heat to the continuous furnace radiators, and FBOT is the appropriate pump by design. major continuous galvanizing operators galvanizing systems operate such loops for years.
6. Brazilian steel sector context
Brazil is the world's ninth-largest raw steel producer (IABr/WSA 2024 data), with installed capacity of approximately 52 million tons per year distributed across about 25 integrated and semi-integrated mills.
The Brazilian integrated steelmaking park concentrates capacity of tens of millions of tons per year, distributed among a few large operators in the Southeast and South regions.
The sector is regulated by IABr and serves both the domestic market (construction, automotive, white goods, packaging) and exports (semi-finished slabs and coils).
FB Bombas has served the Brazilian steel sector for more than five decades, with supply to all main operators. The competitive position is dominant national supplier for process water, cooling, emulsion, effluent and thermal oil pumps — applications where FBCN and FBOT technology is mature and local support accelerates unplanned downtime resolution. The company does not compete in slurry pumps for steel sludges (specialized supplier territory) or multi-stage high-pressure pumps for descaling sprays (supplier territory such as Hauhinco and Hammelmann).
