1. The Brazilian fertilizer chain: pumping points
The Brazilian fertilizer industry operates in three distinct stages with very different pumping requirements. The first is raw-material handling: sulfuric acid (97-99%), phosphoric acid (52-54% P₂O₅) and anhydrous ammonia. The second is intermediate production: DAP, MAP, ammonium sulfate, urea, granulated NPK and liquid NPK. The third is dispatch and final formulation, including liquid solutions for foliar application and suspensions for fertigation.
FB Bombas operates across all three stages, with clear scope differentiation: concentrated acids (stage 1) require special materials at the edge of the standard catalog; liquid and molten intermediates (stage 2) are natural territory for FBCN stainless and FBE; dispatch and formulation (stage 3) are broadly covered by FBCN in lined cast iron or 316 stainless.
| Product | Stage | Recommended material | FB line |
|---|---|---|---|
| Sulfuric acid 98% | Raw material | Super-duplex (out of scope) | N/A |
| Diluted phosphoric acid 30% | Process | 316L stainless | FBCN |
| Ammonium sulfate (solution) | Intermediate | 316 stainless | FBCN |
| Molten urea (132 °C) | Intermediate | 316L stainless with heating jacket | FBE |
| Liquid NPK (solution) | Final product | 316 stainless | FBCN |
| Glycerin (biodiesel/agro by-product) | Viscous by-product | Carbon steel | FBE |
2. Liquid NPK and suspensions: where FBCN 316 stainless is the choice
Liquid NPK is an aqueous solution of N (urea, ammonium nitrate), P (monoammonium or diammonium phosphate) and K (potassium chloride or sulfate) with total concentration between 28% and 35%. pH ranges 5.5 to 7.0 and salinity is high, a combination that progressively attacks carbon steel and requires AISI 316 stainless for service life above 5 years.
For liquid NPK transfer between tanks, loading to tank trucks and inline blending dosage, FBCN in 316 stainless construction with type-21 mechanical seal (ceramic × graphite × viton) and AISI 304 spring covers 90% of applications. For suspensions with undissolved solids (fine mineral fillers), switch to semi-open impeller and widen the radial clearance, keeping the casing in stainless.
3. Molten urea: territory of FBE with thermal jacket
Urea melts at 132.7 °C and beyond that point becomes a viscous liquid (~3-5 cP) with rapid crystallization tendency as soon as temperature drops below 110 °C. Conventional centrifugals suffer from crystallization under low rpm or shutdowns: the impeller literally "locks" in place. The technical solution is a gear pump with heating jacket that keeps the product fluid during operation and controlled shutdowns.
FBE with jacket for saturated steam at 6 bar (~165 °C) or thermal fluid at 180 °C serves molten urea in internal transfer of prilling or humid granulation plants. 316L stainless construction is mandatory: cast iron contaminates the product and generates unstable ammonium carbamate. For larger granulation systems (>20 ton/h), consider two FBE in parallel with VFD for maintenance without plant shutdown.
4. Dilute sulfuric and phosphoric acids: standard-catalog limits
Sulfuric acid in intermediate concentrations (10-70%) is the most aggressive regime in the fertilizer industry: both 316L stainless and carbon are inadequate, and duplex 2205 is the minimum material. Above 93%, paradoxically, carbon steel becomes viable again (passivation by ferrous sulfate), but the 10-93% range requires super-duplex 2507 or alloys.
FBCN in duplex 2205 is available on consultation for specific projects. For concentrations above 70% and for industrial phosphoric acid in high concentration (>50% P₂O₅), the honest technical recommendation is to specify a supplier specialized in super-duplex/alloys (FB Bombas can refer partners). For process dilutions (sulfuric acid <10%, phosphoric <30%), FBCN 316L stainless serves and is the correct cost-benefit choice.
5. Regulatory standards and safety in fertilizer plants
Brazilian fertilizer plants operate under a restricted set of standards: NR-15 (unhealthy activities), NR-20 (safety in flammables and combustibles, relevant for molten urea and ammonia), NR-23 (fire protection), NBR 14725 (FISPQ: chemical product safety data sheet) and MAPA regulations for fertilizer registration. ABNT NBR 13902 specifically addresses pumps for industrial chemical service and is the reference standard for datasheets.
For classified areas (Zone 1 and Zone 2 per IEC 60079), the pump motor must be Ex-d or Ex-e certified by an accredited Brazilian body (INMETRO). FB Bombas supplies the motor-pump set already configured for the correct class from the datasheet: the customer specifies zone, gas and temperature, FB delivers complete compliance documentation.
6. Center-pivot fertigation and foliar application
Fertigation (application of diluted fertilizer in the irrigation water itself) is one of the fastest-growing operations in Brazilian agribusiness, especially in high-value crops like sugarcane, coffee, fruits and vegetables. The typical system injects concentrated solution of liquid NPK, urea, phosphoric acid or potassium chloride into the center-pivot main line via venturi or dosing pump, maintaining final concentration between 0.1% and 2% at application point.
The pumps involved split into two groups: the MAIN pivot pump (high flow, 200-400 m³/h, head 60-80 mwc) that moves irrigation water; and the DOSING pump (small flow, 0.5-5 m³/h, head 20-40 mwc) that injects concentrated fertilizer solution with precision.
For main pivot pump in fertigation with very dilute solution (<5% NPK in water), FBCN in cast iron with aluminum bronze impeller is technically adequate: cast iron tolerates the slightly acidic pH of dilution and bronze avoids galvanic corrosion. For intermediate concentrations (5-15%), switch to FBCN in 316 stainless. For dosing pump of concentrated solution (>20%), FBE with small motor and VFD for flow control is the standard configuration: gear ensures dosing precision that centrifugal cannot achieve at small flows.
Foliar application via agricultural sprayer uses piston or diaphragm pumps (not centrifugal, not gear), outside FB Bombas scope.
7. Agricultural defensives: industrial formulation at Bayer, Syngenta, Basf
The Brazilian agrochemical defensives industry (formulation of herbicides, fungicides and insecticides) operates in highly complex chemical plants: multinationals Bayer, Syngenta, Basf, Adama, Corteva and nationals like Ourofino, Nortox, Sipcam Nichino have units in SP, MG, GO, PR and MT. The pumps of these plants must be sized by the specific active ingredient (a.i.) of the product, by formulation solvents (xylene, cyclohexanone, water + surfactant) and by final formulation viscosity.
FB Bombas serves water-soluble formulations (SL, Soluble Liquid) and concentrated suspensions (SC, Suspension Concentrate) with the FBCN line in 316L stainless; emulsion formulations (EC, Emulsifiable Concentrate) with organic solvent and concentrated oily formulations with the FBE line.
Critical particularities of defensive formulation: many active ingredients have specific ANVISA and MAPA regulation requiring COMPLETE traceability of the motor-pump set (datasheet with batch, stainless raw-material certificate, chemical compatibility declaration signed by FB responsible engineer). Organic solvents (xylene, toluene) are flammable and classify the area as Zone 1 or 2 (NBR IEC 60079): Ex motor mandatory. Surfactant formulations generate foam if suction is poorly sized (marginal NPSHa or excessive turbulence).
FB Bombas calculates NPSHa with ample margin and recommends vacuum-break valve at suction as standard practice for this industry.
8. Logistics: port unloading, terminal and tank truck
Brazil imports about 80% of consumed fertilizers: 40 million tons/year in urea, MAP, KCl and DAP arriving through ports of Paranaguá, Santos, Rio Grande, Itaqui and Vila do Conde. Port fertilizer operation involves solid bulk unloading from ship (not pumped) and water dilution OR direct unloading of imported liquid fertilizers (UAN, Urea Ammonium Nitrate; dilute acids, concentrated solutions).
For liquid operation, FB Bombas serves with FBCN in 316L stainless: high flows (500-3,000 m³/h per pump), moderate head (40-60 mwc), IE3 motor with VFD for flow control per port operation.
After port, land logistics moves fertilizer via tank truck (typical 30 m³ capacity) or train to distributors, cooperatives and farms. Tank truck unloading at destination is a short-cycle operation (15-30 min per unloading) requiring self-priming pump, as suction is negative (truck parked on flat floor, tank above). FBCN with priming system or FBE (intrinsically self-priming) serve this operation.
For distributors and cooperatives receiving multiple trucks per day (Lar, Coamo, C.Vale, Coopavel, Cocamar), standard FB Bombas configuration is FBCN with Venturi vacuum priming attached, flow 800-1,200 L/min, motor 7.5-15 kW, panel with automatic start by truck presence sensor.
9. Most common errors in fertilizer and agro-industry projects
In over 82 years serving the Brazilian industrial market, FB Bombas has mapped the recurring errors that appear in fertilizer and agro-industry projects. Knowing them before closing the project avoids premature corrosion, product contamination, regulatory fine and premature equipment replacement. The 8 most frequent:
- Specifying carbon steel pump for liquid NPK: corrosion in <12 months, product contamination with iron, loss of fertilizer quality warranty
- Under-sizing the heating jacket on urea pump: product crystallization on shutdown and mechanical impeller seizing
- Specifying 316L stainless for 50% sulfuric acid: rapid chemical degradation, failure in <6 months; intermediate H2SO4 range requires super-duplex 2507
- Forgetting documentary traceability in defensive plant: ANVISA/MAPA fine in quality audit, batch suspension
- Installing conventional motor in plant with organic solvent (xylene, toluene): NR-20 non-compliance and explosion risk
- Not sizing vacuum-break valve in surfactant formulation: foam at suction, cavitation and imprecise dosing
- Using centrifugal pump without priming in tank truck unloading: slow operation, product loss by aeration, daily operational rework
- Not considering parallel maintenance (1+1 redundancy) in 24/7 operation plant: unplanned shutdown costs millions in contractual reimbursement
