Steam boiler sizing & specification
JIELI equipment selection · Capacity, fuel and complete system scope
Compare steam boiler options using demand, pressure, fuel and complete boiler-room scope. Start with the capacity you need, your fuel and project country; use the workbook to check supplier offers and excluded equipment. Unknown technical details can be reviewed with JIELI.
Selection information
A stable plant needs steam capacity, pressure, combustion, water treatment, condensate, efficiency, controls and the supply boundary to agree with each other.
Record normal, minimum and simultaneous peak demand in kg/h or t/h. Separate warm-up demand and distribution losses; do not add every machine nameplate at full load. Compare the steam boiler capacity bands against this operating profile.
State the required process pressure and proposed boiler outlet pressure, including distribution losses. Identify whether each value is gauge or absolute pressure and whether the duty requires saturated or superheated steam.
For a gas-fired steam boiler, confirm gas composition and pressure available at the burner. For a biomass-fired steam boiler, confirm moisture, heating value, particle size and ash. Specify the grade of any liquid fuel.
Provide limits for NOx, SOx, particulate matter and stack discharge, plus any continuous monitoring or approval requirements.
Define softened or demineralized water, deaeration, blowdown treatment, condensate recovery and the available raw-water analysis.
State the efficiency target, operating load, feedwater temperature and fuel heating-value basis (LHV or HHV). List the economizer, condensate-return and blowdown heat-recovery scope included in that comparison.
State preferred control components or PLC/DCS platform, automation level, remote communication needs, and preferred instrument grade or brand level.
Clarify whether the requirement covers the boiler only or a complete plant with burner, water treatment, feed system, stack, controls and site services.
Condensate return engineering
This comparison isolates the saturated-liquid sensible heat that leaves with 1 t/h of condensate. It makes the pressure effect visible before adding flash-steam recovery, makeup-water treatment, chemical or pumping benefits.
Pabs = (Pg + 1.0332) × 0.0980665 MPaQloss = hf × 1,000 ÷ 4.1868 kcal/hVgas = Qloss ÷ 8,600 Nm³/hUSD = (Vgas × 4) ÷ 7.20| Gauge pressure | Absolute pressure | Saturation temp. | Saturated liquid hf | Sensible heat loss | Share of hg | Gas equivalent | USD / h |
|---|---|---|---|---|---|---|---|
| 2 kgf/cm²(g) | 2.975 bar(a) | 133.24°C | 560.22 kJ/kg | 133,810 kcal/h | 20.56% | 15.56 Nm³/h | US$8.64 |
| 3 kgf/cm²(g) | 3.955 bar(a) | 143.21°C | 602.98 kJ/kg | 144,020 kcal/h | 22.03% | 16.75 Nm³/h | US$9.30 |
| 4 kgf/cm²(g) | 4.936 bar(a) | 151.35°C | 638.09 kJ/kg | 152,400 kcal/h | 23.22% | 17.72 Nm³/h | US$9.85 |
| 5 kgf/cm²(g) | 5.917 bar(a) | 158.29°C | 668.13 kJ/kg | 159,580 kcal/h | 24.25% | 18.56 Nm³/h | US$10.31 |
| 6 kgf/cm²(g) | 6.897 bar(a) | 164.36°C | 694.55 kJ/kg | 165,890 kcal/h | 25.15% | 19.29 Nm³/h | US$10.72 |
| 7 kgf/cm²(g) | 7.878 bar(a) | 169.78°C | 718.23 kJ/kg | 171,550 kcal/h | 25.95% | 19.95 Nm³/h | US$11.08 |
| 8 kgf/cm²(g) | 8.859 bar(a) | 174.69°C | 739.77 kJ/kg | 176,690 kcal/h | 26.68% | 20.55 Nm³/h | US$11.41 |
| 9 kgf/cm²(g) | 9.839 bar(a) | 179.18°C | 759.58 kJ/kg | 181,420 kcal/h | 27.36% | 21.10 Nm³/h | US$11.72 |
| 10 kgf/cm²(g) | 10.820 bar(a) | 183.34°C | 777.96 kJ/kg | 185,810 kcal/h | 27.98% | 21.61 Nm³/h | US$12.00 |
| 11 kgf/cm²(g) | 11.801 bar(a) | 187.21°C | 795.14 kJ/kg | 189,920 kcal/h | 28.57% | 22.08 Nm³/h | US$12.27 |
| 12 kgf/cm²(g) | 12.781 bar(a) | 190.83°C | 811.29 kJ/kg | 193,770 kcal/h | 29.12% | 22.53 Nm³/h | US$12.52 |
Engineering note: “kg pressure” is treated as kgf/cm² gauge. Saturated-water properties follow IAPWS-IF97; the table uses the saturated-liquid enthalpy only. Direct gas equivalence assumes 100% conversion, so actual purchased fuel is higher after boiler and system efficiency. It excludes flash-steam recovery, makeup-water cost, treatment chemicals and piping losses. References: IAPWS-IF97, NIST steam tables and the U.S. DOE condensate-return guidance.
Boiler construction
Fire-tube and water-tube describe construction; gas and biomass describe fuel. Compare a gas-fired steam boiler and a biomass-fired steam boiler at the same steam demand, pressure, feedwater temperature and return-condensate basis before selecting the arrangement.
WNS boiler photographs
Four equipment views from the JIELI THERMAL library show the installed boiler, burner interface, boiler-room arrangement and a workshop production row. Some images have been retouched for presentation; verify the proposed installation against the project layout and equipment list.
Steam demand screening
Capacity bands are a starting point, not a confirmed model offer. Check the linked manufacturer data for the selected fuel and pressure; any duty outside the published model data needs a separate engineering review.
Use these capacity bands to screen the required steam output. Compare offers at the same pressure, steam condition and feedwater temperature, and keep startup demand and reserve capacity explicit.
| Requested steam duty | Output | Common configuration | Selection note |
|---|---|---|---|
| 1 t/h | 1,000 kg/h | Compact fire-tube boiler | Check peak demand and burner turndown |
| 2 t/h | 2,000 kg/h | WNS gas/oil boiler | Confirm gas pressure and feedwater temperature |
| 4 t/h | 4,000 kg/h | Fire-tube or project-specific option | Evaluate condensate return and economizer |
| 10 t/h | 10,000 kg/h | Gas/oil or biomass system | Compare the fuel analysis, emissions and complete plant scope |
| 20 t/h | 20,000 kg/h | Engineered water-tube system | Review redundancy, pressure and site logistics |
| 35 t/h | 35,000 kg/h | Engineered water-tube or multi-boiler plant | Confirm pressure, site logistics, redundancy and water-treatment capacity |
Boiler-room scope
To verify manufacturing capability and inspect real project photos, use the JIELI THERMAL steam boiler product and factory resources.
Workshop and project photographs
Use the fabrication, delivery and installed-system views to identify the boiler arrangement, burner or grate, piping interfaces and maintenance access. Confirm which equipment is included and which work remains at site before comparing the offers.
WNS fire-tube packages and SZS water-tube installations with real burner, piping and boiler-room interfaces.
DZL, DZG and DZW boilers for wood chips and other qualified biomass fuels, shown from fabrication through field installation.
Fabrication views for DZL and SZL industrial steam boiler arrangements. Confirm pressure-part construction, furnace configuration and included auxiliaries against the selected model's drawings.
Use the photographs and field video to check the proposed boiler-room arrangement. Shipping condition, site assembly and auxiliary scope must be confirmed in the supplier's layout and equipment list.
Procurement & RFQ control
Issue the same steam-demand profile to every bidder, then compare the replies in the workbook below. Record steam conditions, water and condensate assumptions, fuel, efficiency basis, controls, delivery condition and exclusions. A missing response remains an open question, not an included item.
Record normal, peak and startup demand, pressure, steam condition, operating hours, turndown and redundancy requirements.
Define raw-water analysis, softening or RO, deaeration, feedwater temperature, blowdown and expected condensate-return percentage.
Request GA drawings, P&ID, data sheets, control logic, inspection records, manuals, packing list and commissioning responsibilities.
Confirm packaged or field-assembled delivery, transport limits, project code, emissions, civil work, erection, piping and excluded services.
Pressure: distinguish gauge from absolute pressure and pressure at the boiler outlet from pressure required at the process user. State saturated or superheated steam and any steam-quality requirement.
Feedwater: an offer calculated with hot returned condensate is not equivalent to one calculated with cold makeup water. Ask for the assumed feedwater temperature and return percentage before comparing fuel consumption.
Steam boiler rating basis: ask whether kg/h or TPH means actual evaporation at the specified working pressure and feedwater temperature, or equivalent evaporation “from and at 100°C” (F&A). These figures are not interchangeable. Boiler horsepower (BHP) is a heat-output rating, not a pump-motor rating. Record each bidder's rating basis and actual guaranteed steam output in the comparison workbook before comparing prices. See Spirax Sarco's boiler-rating explanation.
Fuel and load: compare the same fuel heating value, LHV or HHV efficiency basis, operating load and included economizer. A full-load efficiency claim does not describe an entire variable-load year.
Quotation rule: compare the same steam output, pressure, feedwater temperature, fuel, efficiency basis and scope. Boiler-body price alone cannot represent the cost of a complete steam plant.A gas-fired package and a biomass-fired steam plant should be priced against the same steam output and pressure, but their auxiliary equipment is different. Ask for separate prices for the boiler, burner or grate, fuel handling, water treatment, economizer, dust and ash equipment, controls, delivery and site work. This makes an equipment-only offer distinguishable from a complete boiler-room proposal.
Start with your required t/h, fuel, application and project country. If pressure or water data is not yet available, mark it as unknown so the remaining selection questions can be identified. Request a steam boiler quotation.
Download steam boiler quotation comparison (Excel)
Includes English, Spanish and Russian sheets. Fill the buyer column, compare up to three suppliers and list exclusions or missing data.
Download 20 WNS / DZL model records and project input sheet (Excel, EN / ES). Use the manufacturer catalogue beside your comparison workbook; confirm fuel, pressure, water treatment and supply boundaries.
Manufacturer reference: Argentina WNS12-1.25, 12 t/h (PDF, EN / ES). Use this documented gas-fired steam boiler reference alongside the workbook. Compare your required pressure, gas supply, water treatment and installation boundary; the same steam output does not make two packages equivalent.
Engineering FAQ
A reliable quotation needs process and water-side data. A capacity-only request cannot establish consumption, controls or system scope.
Begin with a steam-demand schedule: normal, minimum and simultaneous peak consumption, plus the duration of startup loads. A 10 TPH steam boiler means 10,000 kg/h of steam output, not 10 MW of useful heat. Check pressure, steam condition, feedwater temperature and distribution losses before allowing for future demand or standby capacity. Adding every machine nameplate at full load can overstate the required output.
Fire-tube units pass combustion gas through tubes surrounded by water and are common for many industrial duties. Water-tube units circulate water through externally heated tubes and generally suit higher capacity, pressure or faster response.
Hot condensate reduces makeup water, fuel and chemical treatment. Its return rate and temperature affect the feed system and expected efficiency.
Provide steam output, pressure, steam condition, fuel data, feedwater temperature and analysis, condensate return, operating hours, emissions limits and location. For a gas-consumption estimate, ask the supplier to show the heat balance: steam flow (kg/h) × steam-to-feedwater enthalpy rise (kJ/kg), divided by efficiency and gas heating value (kJ/Nm³), gives Nm³/h on the declared gas-volume reference basis. This screening balance needs the same LHV or HHV basis throughout; blowdown, part-load operation and auxiliary electricity must be assessed separately.
The quotation should state the boiler basis, combustion equipment, water treatment, feedwater, heat recovery, blowdown, condensate, controls, emissions boundary, documentation, delivery condition and excluded site work.
State whether steam heats through a jacket or heat exchanger, contacts the product directly, or serves a validated sterilization process. Ask the process-equipment supplier to define the required steam grade and acceptance criteria at the point of use. Record water treatment, permitted additives, condensate segregation and any filtration or separate clean-steam generation in the quotation scope. An ordinary plant-steam boiler is not automatically a clean-steam system.
Request a selection check
Send capacity, pressure, fuel and project country, plus any supplier scope you want to compare. Check whether each price includes water treatment, feedwater pumps, economizer, blowdown, condensate recovery, emissions equipment and commissioning. A lower boiler-only price is not a like-for-like plant quotation. Unknown values can be reviewed; opening either draft does not send an enquiry.