Read textile steam and condensate records before claiming a loss

Fictional record map for 1 June to 1 July 2026 (Asia/Kolkata; end exclusive). The 900 t header total is allocated to 360 t of direct injection into process water and 540 t of indirect heating. In this stipulated configuration, only the indirect route feeds the liquid-return meter, which records 432 t. The difference of 540 − 432 = 108 t remains unattributed. It is not an identified leak or actual loss. The direct branch being outside this return route does not mean its 360 t is wasted, loss-free, or permanently retained in the water. All totals use metric tonnes and the same interval; that alone does not establish a same-water cohort. Inventory changes, separate vapor or discharge streams, and measurement uncertainty are not quantified here. These cards show record relationships, not equipment positions, operating instructions, flow-proportional sizes, or a complete physical balance. No loss or recovery percentage, energy, fuel, emissions, saving, or real-factory conclusion follows.

By Divya Khatwani

A textile mill’s steam-supply schedule can add up exactly while a proposed loss percentage still lacks support. In the fictional case below, reject the claim that 52% of supplied steam was lost. The header and the liquid-return meter cover different routes.

Use this guide when utilities, finance or reporting colleagues ask what a set of steam and return totals proves. The immediate decision is how to describe the observations and which existing records to request.

Set the measurement boundary before subtracting

All quantities and records below are invented. The interval begins at 00:00 on 1 June 2026 and ends just before 00:00 on 1 July 2026, in India Standard Time (UTC+05:30). All four totals use metric tonnes (t) of mass on a consistent basis. They are exact for this arithmetic exercise; real meters are not assumed to have zero uncertainty.

Direct injection mixes steam into the heated liquid; indirect heating transfers heat across a separating surface. Spirax Sarco’s explanation of heating arrangements describes this distinction.

• SH-01: 900 t of steam crosses the process-header supply boundary.

• DI-01: 360 t is supplied by direct injection to the mill’s process-water heating tanks. The steam enters the water rather than a heating coil.

• IH-01: 540 t is supplied to indirect-heating equipment connected to the specified condensate collection route.

• CR-01: 432 t of liquid crosses the return meter. Only the IH-01 route feeds this meter.

The fictional drawing R-01 and owner note O-01 stipulate a complete supply split: SH-01 feeds DI-01 and IH-01 only. There is no additional branch, separate supply input or second counting of recovered steam inside that split.

Those records also place CR-01 after collection and before mixing with makeup water. It measures liquid crossing once, with no counted recirculation. Neither the DI-01 process water nor any other supply feeds CR-01. This is the stipulated arrangement for this mill, not a description of every textile machine or direct-injection system.

A closed supply schedule does not settle the return question

The supply schedule closes: 900 − 360 − 540 = 0 t. Every tonne at the header has a branch assignment in this exercise. That checks the allocation of the supplied figures; it does not establish the later fate of the water.

Subtracting the liquid return from total header supply gives 900 − 432 = 468 t. Dividing by header supply gives 468 ÷ 900 × 100 = 52%. Both calculations are arithmetically correct. Calling the result “52% steam loss” is unsupported.

The subtraction combines 360 t sent to a route outside CR-01’s coverage with a further 108 t difference on the indirect route: 468 = 360 + 108. A route outside the return meter is not an identified loss. Equally, excluding DI-01 from this comparison does not demonstrate that its 360 t all stayed in process liquid, transferred useful heat or experienced no venting, leakage or other loss.

A liquid-return meter covers only streams routed through it; it does not by itself quantify direct-injection steam use and may omit flashed vapor. Spirax Sarco’s measurement discussion explains these limits.

Keep the indirect-route difference unattributed

For the route that feeds CR-01, the observed difference is 540 − 432 = 108 t. Record it as an unattributed difference between indirect steam supply and measured liquid return. The records do not establish that 108 t was lost, avoidable or recoverable. It is not an upper bound on all plant losses.

The paired meter totals also give 432 ÷ 540 × 100 = 80%. The defensible label is the observed liquid-return-to-indirect-steam-supply mass ratio for these meters and this interval. It is not a recovery efficiency or a demonstrated fraction of this month’s particular steam that returned.

Matching dates do not establish that the water crossing CR-01 originated in the steam supplied during this interval. Opening and closing liquid and vapor inventories have not been quantified. Nor does this record set quantify flash or vent streams, diversions, discharges or measurement uncertainty. These are unresolved evidence gaps, not assigned explanations for the 108 t.

Flash steam can arise during normal trap operation. Where vapor takes a separate path, a liquid-only meter does not record it. The US Department of Energy’s 2002 steam survey guide discusses this in section 6.2.2.1 and the separate vapor and liquid paths in section 6.5.

Ask the authorised technical owner for the missing records

Keep the four totals, their meter IDs, dates, units and the route drawing together. Then ask the authorised utilities or technical owner for existing evidence that answers the following questions.

• Does the installed route match the drawing? Request the current heat-use and return-path map, meter positions and owner confirmation of other feeds or repeat crossings.

• What was held at the start and end? Request the relevant existing liquid- and vapor-inventory records for the same boundary and interval. Leave the change unknown if the records are absent.

• Which other streams are documented? Request dated records for any separately recorded vapor, diverted liquid or discharges, with their locations and connections. Do not enter a presumed flash or discharge quantity to force the figures to balance.

• How comparable are the measurements? Ask the technical owner to assess the recorded mass basis, compensation, calibration and uncertainty using the available meter records.

If the decision requires a physical loss or recovery quantity, obtain a separately supported technical assessment. This is a request for existing records and expert interpretation; it gives no instructions for operating equipment or conducting physical tests.

Carry a bounded conclusion into the handover

A suitable note for this fictional case is: During the stated June interval, CR-01 recorded 432 t of liquid while IH-01 recorded 540 t of steam supply. The observed meter-period mass ratio is 80%, and the 108 t difference remains unattributed. The 52% gross header-minus-return figure is not a measured steam-loss rate.

The case supplies no pressure, temperature, steam-quality, enthalpy, fuel-efficiency or heat-output data, and no assessment of treatment suitability or recoverability. It supplies no emissions factor, GHG classification, purchased-energy treatment, physical improvement, saving or prior-period comparison. Keep those separate decisions open rather than extending these mass records into unsupported conclusions.

Related record checks

For a shared-meter allocation question, see Prepare shared-meter and leased-premises energy data without double counting.

For the general ratio check, see Calculate intensity from a matched numerator and denominator.

Sources checked 13 October 2026. The example is fictional and does not present a client result, operating recommendation or independently verified performance finding.