1. Overview

This document describes a standard steam-boiler room setup for a fire-tube, horizontal industrial boiler installation, covering the fuel/combustion side, the steam generation and distribution side, and the feed-water treatment train. It is intended as a reference for equipment layout planning, commissioning checks, and compliance review against RSC (Remediation Coordination Cell) guidance and BNBC 2020.

2. Equipment Schedule

The table below lists each station shown in the reference boiler room layout, its function, and the key design parameter to confirm during equipment selection or vendor submittal review.

#	Equipment / Station	Function	Key Parameter / Spec
1	Electric Control Panel	Central control & safety interlocks for burner, feed pump, flame failure, low-water and high-pressure trips	As per burner/boiler OEM control schematic
2	Fuel Supply System	Delivers fuel (gas / diesel / HFO) to burner via filter, pressure regulator & shut-off solenoid	Per burner capacity & fuel type
3	Burner	Ignites fuel-air mixture to fire the furnace tube	Sized to boiler rated capacity (kg/hr steam)
4	Boiler (Fire-tube, horizontal)	Generates steam via flue-gas heat transfer through fire tubes	Rated pressure, capacity (TPH), fitted with safety valve, pressure gauge, water level gauge
5	Economizer	Recovers flue-gas waste heat to preheat feed water	Typically improves efficiency 5–10%
6	Steam Header	Collects & distributes steam to plant steam supply lines	Design pressure ≥ boiler MAWP
7	Water Softener	Removes hardness (Ca/Mg) via ion-exchange resin	Output hardness < 1 ppm as CaCO3 (typical)
8	Water Tank	Storage / buffer for softened water	Sized for min. 20–30 min. feed reserve
9	Deoxygenated Water Pump	Transfers softened water to/through deaerator	Per feed water flow rate
10	Deaerator	Removes dissolved O2 and CO2 (mechanical + thermal, flash steam)	Target dissolved O2 < 0.007 ppm (EN standard)
11	Chemical Dosing Barrel	Injects oxygen scavenger, alkalinity builder & sludge conditioner	Dosing rate per water analysis / boiler TDS control
12	Feed Pump (Duty/Standby)	Delivers treated, deaerated water into boiler against boiler pressure	Discharge head ≥ 1.25 × boiler MAWP

3. Process Flow

3.1 Feed Water & Steam Side

Raw Water → Water Softener → Water Tank → Deoxygenated Water Pump → Deaerator (+ Chemical Dosing) → Feed Pump → Boiler → Economizer (flue-gas heat recovery) → Steam Header → Steam Supply (plant)

3.2 Fuel & Combustion Side

Fuel Supply System → Burner → Boiler Furnace → Flue Gas → Economizer → Chimney / Stack

3.3 Control

The Electric Control Panel supervises burner firing sequence, feed pump duty/standby switching, and monitors safety interlocks (flame failure, low water level, high steam pressure) across both sides of the process.

4. Feed Water Treatment Chain — Purpose of Each Stage

Water Softener: removes hardness-forming ions to prevent scale build-up on fire-tube surfaces, which reduces heat transfer and risks tube overheating/failure.
Water Tank: provides buffer storage and residence time ahead of deaeration.
Deaerator: removes dissolved oxygen and CO2 — the leading cause of pitting corrosion in boiler shells, tubes, and condensate/feed piping.
Chemical Dosing Barrel: maintains correct alkalinity, scavenges residual oxygen, and conditions sludge/TDS for controlled blowdown.
Feed Pump: delivers conditioned water into the pressurised boiler shell; run in duty/standby configuration for continuity.

5. Water Quality Parameters (EN Standard Reference)

Indicative feed-water and boiler-water limits for a low/medium-pressure fire-tube boiler (below 20 bar). Actual limits should be confirmed against the boiler OEM’s water quality specification and RSC/CKDL 2020 framework requirements.

Parameter	Feed Water Limit	Boiler Water Limit (typical, <20 bar)
pH @ 25°C	8.5 – 9.5	10.5 – 11.8
Total Hardness (as CaCO3)	< 1 ppm	—
Dissolved Oxygen	< 0.007 ppm (7 ppb)	—
TDS	< 5 ppm	< 3000 ppm (blowdown controlled)
Silica (as SiO2)	< 0.02 ppm	< 150 ppm
Iron (as Fe)	< 0.05 ppm	—
Alkalinity (P-alkalinity)	—	sufficient to buffer, per dosing program

6. Room Layout & Safety Clearances (RSC / BNBC 2020 Aligned)

Item	Minimum Clearance / Requirement	Reference
Boiler front (burner side) to wall	Min. 2.0 m for burner removal & maintenance access	BNBC 2020 / RSC Guidance
Boiler rear / sides to wall	Min. 1.0 m all-round for inspection & tube cleaning	BNBC 2020
Boiler top to ceiling/roof	Min. 1.5 m (or per chimney/duct routing needs)	RSC Guidance
Room ventilation	Continuous fresh-air supply + power ventilation for combustion air & heat removal; min. 2 air changes/hr	BNBC 2020, Fire Safety
Emergency exits	Minimum 2 independent exits from boiler room, outward opening	RSC / Fire Safety Rules
Fire-fighting provision	CO2/DCP extinguishers + fire hydrant point at room entry; fire-rated door (min. 2 hr)	BNBC 2020 Part 4
Safety valve discharge	Vented to safe location outside room / above roof, away from walkways	IBR / RSC Guidance
Electrical fittings	Flame-proof / weatherproof fittings near fuel & burner zone	BNBC 2020 Electrical Code

7. Commissioning & Inspection Checklist

Verify safety valve set pressure and test lift/reseat before first firing.
Confirm low-water cut-off and flame-failure interlocks trip correctly (simulated test).
Check economizer and feed line for leak-tightness under hydro test pressure.
Verify water softener regeneration cycle and confirm treated water hardness < 1 ppm.
Confirm deaerator vent steam flow and dissolved oxygen at outlet meets target.
Log chemical dosing rates against first-week boiler water TDS/alkalinity trend.
Confirm fire-fighting equipment, room ventilation, and emergency exits are in place before occupancy/use.
Record burner combustion efficiency test (O2/CO in flue gas) and file with commissioning report.

8. References

Bangladesh National Building Code (BNBC), 2020 — Fire Safety & Mechanical Services provisions.
RSC (Remediation Coordination Cell) Guidance — boiler installation & water quality compliance framework.
Bangladesh Labour Act — provisions relevant to pressure vessel/boiler operation and worker safety.
Boiler OEM technical manual and water treatment vendor specification sheets (project-specific).

Boiler Installation