The steam requirement of the dairy factory, and therefore the boiler, is determined not by the label of the pasteurizer, but by the peak steam of the machines operating at the same time. Since cheese and yoghurt milk comes out of the pasteurizer hot, regeneration is limited: a 10,000 L/h drinking milk pasteurizer draws ≈ 99 kg/h steam, while a cheese milk pasteurizer at the same flow rate draws ≈ 556 kg/h. In medium-sized facilities, the biggest item is often CIP heaters; If milk powder is produced, the spray dryer determines the boiler pressure.
Which machine draws how much steam?
Values were calculated using the wizard’s calculation engine, with typical inputs for each machine, and for a single machine. Pressure is the saturated steam pressure required at the machine inlet.
| Machine | Typical capacity | Steam | Pressure |
|---|---|---|---|
| Pasteurizer — drinking milk (HTST, 93% regeneration) | 10,000 L/h | 99 kg/h | 3 bar g |
| Pasteurizer — cheese milk (74 → 32 °C outlet) | 10,000 L/h | 556 kg/h | 3 bar g |
| Pasteurizer — yoghurt / buttermilk (95 → 43 °C) | 5,000 L/h | 385 kg/h | 4 bar g |
| Cream pasteurizer (40% fat) | 2,000 L/h | 79 kg/h | 3 bar g |
| Double-walled pasteurization / yoghurt tank (4 → 65 °C, 50 min) | 1.000 L | 148 kg/h | 1 bar g |
| Cheese boat (curd cooking) | 10,000 L | 298 kg/h | 1 bar g |
| Kad kashar boiling – kneading machine | 1,000 kg/h curd | 94 kg/h direct · 107 kg/h jacketed | 3 bar g |
| Curd boiler (jacketed, 30 → 90 °C, 40 min) | 1.000 L | 193 kg/h | 2 bar g |
| Cream / cooking boiler (4 → 90 °C) | 500 L | 117 kg/h | 1 bar g |
| Process tank — brine (20 → 85 °C, 60 min) | 2,000 L | 260 kg/h | 2 bar g |
| Yogurt incubation room | 60 m² | 26 kg/h | 1 bar g |
| CIP circuit (heater ΔT 20 K) | 20 m³/h | 775 kg/h | 5 bar g |
| Case washing (tunnel type) | 1,000 cases/h | 250 kg/h | 3 bar g |
| Jerry can washing | 60 cans/h | 42 kg/h | 3 bar g |
| Tanker / silo washing | 25 m³ tanker | 349 kg/h | 5 bar g |
| Process / cleaning hot water (15 → 65 °C) | 5 m³/h | 486 kg/h | 3 bar g |
| UHT — indirect (plate / pipe) | 10,000 L/h | 269 kg/h | 7 bar g |
| UHT — direct steam (injection / infusion) | 10,000 L/h | 1,460 kg/h (1,147 kg/h enters the product) | 8 bar g |
| Evaporator (TVR 5 effect, 12.5% → 50%) | 20,000 kg/h feed | 2,150 kg/h | 10 bar g |
| Spray dryer (210 °C air, milk powder) | 5,000 kg/h concentrate | 4,119 kg/h | 23.3 bar g |
Example: 150 t/day cheese and yoghurt facility
The “Medium facility · 150 t/day” template in the wizard: A facility operating in two shifts (16 hours) producing feta cheese, kashar, yoghurt / buttermilk and butter. Boiler room defaults: line loss 5%, condensate return 70%, growth margin 10%, make-up water 15 °C, fuel natural gas.
| Machine | Quantity × capacity | Peak (kg/h) | Concurrency | Accounted (kg/h) |
|---|---|---|---|---|
| Pasteurizer — cheese milk | 1 × 10,000 L/h | 556 | 100% | 556 |
| Pasteurizer — yoghurt / buttermilk | 1 × 5,000 L/h | 385 | 100% | 385 |
| Cream pasteurizer | 1 × 1,000 L/h | 39 | 100% | 39 |
| Boiled kashar – kneading (jacketed) | 1 × 1,000 kg/h | 107 | 100% | 107 |
| Cheese boat | 1 × 10,000 L | 298 | 50% | 149 |
| Curd boiler (jacketed) | 2 × 2.000 L | 771 | 50% | 385 |
| Yogurt incubation room | 2 × 60 m² | 52 | 100% | 52 |
| Brine tank | 1 × 2.000 L | 260 | 30% | 78 |
| CIP circuit (including tanker line) | 4 × 20 m³/h | 3.100 | 50% | 1.550 |
| Case washing | 1 × 1,000 cases/h | 250 | 100% | 250 |
| Process / cleaning hot water (15 → 60 °C) | 1 × 3 m³/h | 263 | 50% | 131 |
- The simultaneous demand of the machines is 3.683 kg/h; line loss +184 kg/h, deaerator steam +308 kg/h, growth margin +418 kg/h.
- Calculated need 4.593 kg/h → suggested steam boiler 5 t/h.
- Boiler operating pressure 6.5 bar g (maximum use CIP 5 bar g + 1.5 bar margin), design pressure class 8 bar.
- Boiler thermal power ≈ 2.977 kW ≈ 2.560.000 kcal/h; feed water ≈ 105 °C (with deaerator).
- Natural gas at full load ≈ 337 Sm³/h; ≈ 243 Sm³/h at average load (≈ 3.065 kg/h steam).
- The largest share belongs to CIP circuits (42%). Sector supply ≈ 327 kg steam / t milk; Compatible with the range 100–560 kg/t in AB BREF 2019
With the same engine, a small dairy farm (20 t/day; feta cheese, yoghurt, curd; one shift) draws ≈ 704 kg/h and requires a boiler of 0.9 t/h · 6.5 bar g (≈ 491,000 kcal/h). The large integrated plant (1,500 t/day; drinking milk, UHT, yoghurt, cheese and 500 t/day milk powder) draws 18,824 kg/h of process steam; 23,563 kg/h with shares → 24 t/h · 24.8 bar g (25 bar class).
Boiler type and pressure for dairy plant
In the dairy plant, the fluid is steam: yoghurt milk is heated to 95 °C, curd to 90 °C, UHT milk to 138–142 °C; It boils the kashar and gives UHT steam directly to the product. A 90 °C hot water boiler cannot meet these loads. The boiler pressure is determined by the machine requiring the highest pressure:
- Cheese, yoghurt, buttermilk plants: CIP and yoghurt pasteurizer 4–5 bar g → boiler 6.5 bar g, 8 bar class.
- UHT line: 7–8 bar g → boiler 9.5 bar g, 10 bar class.
- TVR evaporator: 10 bar g motivated steam → boiler 11.5 bar g, 12 bar class.
- Milk powder: 210 °C for drying air ≈ 23.3 bar g → boiler 24.8 bar g, 25 bar class. If the air heater of the dryer is fed with thermal oil, in the large model the steam boiler is reduced to 18 t/h · 12 bar class, next to it is a thermal oil boiler of ≈ 3,250,000 kcal/h.
For needs up to 6 t/h, package type and hybrid type steam boilers are suitable, in larger facilities header type water tube steam boiler is suitable; At 2 t/h and above, economizer must be added, which gives the flue gas heat to the feed water. thermal oil boiler option can also be considered for the milk powder dryer. Since kashar boiling and steam directly mixes with the product in UHT, filtered, separator kitchen steam and food-grade boiler water conditioning are required.
How to calculate?
ṁ is the milk flow rate (kg/s), cp ≈ 3.9 kJ/kg·K, t₃ is the exit temperature of the milk from the pasteurizer, η ≈ 0.95 is the heating efficiency, hfg is the heat of evaporation at the usage pressure. Since cheese milk comes out at 32 °C, regeneration can be at most (74 − 32) ÷ (74 − 4) = 60%; It increases to 93% in drinking milk. The wizard calculates the heating peak and cycle average separately in batch machines (curd boiler, tank, cheese vat), applies simultaneity (CIP circuits 30–60%, sequentially working curd boilers 50%), then adds line loss, deaerator steam (automatic above 1.5 t/h), blowdown and growth margin; 70% of indirect condensate is considered return.
You can detail the recommended boiler fuel consumption with the boiler fuel consumption tool.
Use the wizard at the top of the page to calculate with your own list of machines; Boiler Capacity Calculation for all sectors.
The results of the wizard are estimates for preliminary purposes; Boiler selection should be finalized with on-site exploration and engineering calculations. contact us for free pre-engineering support.