Dilute Phase Conveying Air Supply

Dilute Phase Conveying Air Supply

Primary intent: Define dilute-phase conveying air interfaces using material- and route-specific design data.

Required asset: Dilute Phase Interface Schedule

1 — Engineering Answer

Dilute-phase conveying air supply should be selected from a validated material- and route-specific pressure-flow requirement, not from a generic velocity table or tonnes-per-hour shortcut. It governs the interface between conveying design and compressor, blower or vacuum source.

2 — Scope

It records required gas flow, pressure or vacuum, reference condition, turndown, schedule, air quality, connection point and acceptance evidence. It does not independently decide that a material should use dilute phase.

3 — Regime Is Not Compressor Type

A dilute-phase system may use a blower, compressor or vacuum source depending on the required operating envelope. The air mover follows the conveying duty.

4 — Material Basis

If material changes, the validated pressure-flow point may no longer be valid.

5 — Throughput Basis

Record normal, peak and future solids throughput. State whether the validated air requirement corresponds to normal rate, maximum rate, startup, empty line, loaded line, cleanout or another defined state.

6 — Route Basis

The pressure-flow requirement belongs to a specific route and pipe configuration. Record horizontal and vertical sections, bends, diverters, flexible sections, pipe ID, feeder and destination. Route revision is a design change.

7 — Pressure and Flow Together

Specify gas flow together with pressure or vacuum at a defined connection point and operating condition. Flow without pressure cannot prove source capability; pressure without required flow cannot prove conveying capacity.

8 — Flow Reference Condition

Every gas-flow value must state whether it is FAD, standard/reference flow, inlet flow or actual volumetric flow at the conveying-line condition.

9 — Local Pipe Velocity

Where actual local flow is known, v = Qactual/A and A = πD²/4 can report gas velocity. If only FAD or standard flow is available, convert it first. Preserve absolute versus gauge pressure correctly.

10 — No Universal Transport Velocity

Required velocity depends on material and conveying method and should come from specialist design, OEM guidance, pilot testing or validated operating evidence.

11 — Pickup Condition

Gas condition at material pickup can differ from source condition because of feeder leakage, acceleration, fittings and local pressure loss. Record the validated design point at the location defined by the conveying specialist.

12 — Solids Acceleration

Material entering the gas stream must be accelerated. Use the specialist pressure budget.

13 — Complete Pressure Budget

The source may need to overcome conveying-line resistance, feeder/device losses, bends, vertical effects, receiver/filter backpressure and explicit margin. Straight-pipe compressed-air friction is not the final solids-system pressure calculation.

14 — Bends, Wear and Product Damage

Carry bend geometry and material friability/abrasiveness into the interface record. Higher velocity can increase impact severity for some materials. Lowest plugging risk is not automatically the best product-integrity condition.

15 — Feeder Leakage

A rotary valve or other feeder can introduce leakage or pressure-isolation effects. Record supplier data where available. Do not treat every unit of source air as useful transport air at pickup.

16 — Receiver and Filter Backpressure

Destination filtration and separation affect the pressure boundary. Record operating differential pressure where supported. Filter loading can reduce pressure available for conveying.

17 — Positive-Pressure Systems

Define validated source connection pressure-flow requirement, feeder boundary, destination backpressure and operating sequence. The source must meet the requirement at the agreed interface.

18 — Vacuum Systems

Define suction flow and vacuum requirement at the agreed interface with separator/filter conditions and leakage assumptions. Do not translate vacuum duty into an arbitrary positive-pressure compressor equivalent.

19 — Combined Systems

Where vacuum pickup and positive-pressure discharge coexist, maintain separate interfaces unless validated package design combines them. Avoid adding incompatible flow values from different pressure states.

20 — Air Quality

Moisture, oil and particles can affect product quality or material behaviour. Specify treatment from process requirement, not habit.

21 — Moisture and Stability

Changes in material moisture or gas condition can change cohesion and plugging behaviour. If a defined dryness condition is required, state it at the relevant point and operating condition.

22 — Gas Temperature

Record gas temperature where it influences material softening, moisture migration, condensation, oxidation or product quality. Aftercooling, drying and piping can change temperature reaching the conveying system.

23 — Continuous Versus Intermittent Duty

A continuous line can impose sustained utility load; an intermittent line can create repeated peaks and recovery requirements. Record on-time, off-time, batches and production windows rather than only daily average.

24 — Multiple Lines

If several lines share a source, define which can operate simultaneously. Do not apply unexplained diversity. Use actual process schedule, interlocks and credible overlap.

25 — Startup and Clearing

Record whether the line starts empty, partially loaded or with retained material and whether a separate clearing/purge state exists. Normal operating point may not cover every restart condition.

26 — Plugging and Recovery

A plugged line is not automatically evidence of inadequate compressor capacity. Material condition, feeder consistency, obstruction, filter loading, leakage, control sequence and unsuitable regime can contribute.

27 — Low Throughput Diagnosis

Collect solids throughput, pressure trend, gas flow where available, feeder speed, filter differential pressure and material condition on a common timeline.

28 — High Air Consumption

Investigate source flow, operating time, leakage, feeder leakage, pressure setpoint, idle/purge states and production output. Report air per accepted tonne only when both boundaries are consistently measured.

29 — Excessive Wear

Review material abrasiveness, validated velocity, bends, pipe geometry and wear map. Reducing velocity may affect transport stability; changing bend geometry or material can be a separate design option.

30 — Product Degradation

For fragile materials, compare fines or breakage with operating condition, route and bends. Product-quality acceptance belongs in the conveying specification.

31 — Turndown

If throughput varies, define a validated pressure-flow envelope where possible. Source control must remain compatible with conveying stability. Variable speed can reduce energy only within the proven envelope.

32 — Avoid Artificially High Pressure

Do not raise plant header pressure merely to overcome an unsuitable local interface. Verify actual conveying requirement, local losses, feeder, filter and source connection first.

33 — Dedicated Source Versus Plant Air

Shared plant air can expose conveying to unrelated demand swings; dedicated supply adds capital and maintenance. Compare pressure-flow, quality, continuity and schedule before deciding.

34 — Storage Boundary

A receiver can support transient demand or stabilize pressure but cannot make an undersized source sustain a continuous conveying requirement indefinitely. Verify recovery between repeated events.

35 — Temporary / Rental Air

Temporary support requires the exact validated pressure-flow point, connection location, duty cycle, air quality and distribution arrangement. Long hoses, manifolds and treatment can consume pressure.

36 — Capacity Increase

If solids throughput rises, do not scale air demand linearly without validated evidence. Recheck material loading, velocity, pressure loss, feeder, route and destination.

37 — Route Modification

Additional horizontal pipe, vertical lift or bends can invalidate the previous pressure-flow selection. Obtain the revised specialist duty rather than inventing source requirement from length alone.

38 — Worked Example A: Interface, Not Design

Illustrative only. A specialist provides a validated requirement of 7.2 m³/min FAD at a specified source pressure, with reference condition and connection point.

39 — Worked Example B: Local Velocity Screen

Illustrative only. After proper reference-state conversion, suppose actual local flow is 4.5 m³/min in a 100 mm ID section. Q = 4.5/60 = 0.075 m³/s; A = π×0.100²/4 = 0.00785 m²; v ≈ 9.55 m/s. This reports local gas velocity only and does not declare it adequate.

40 — Worked Example C: Duty Cycle

Illustrative only. A line requires validated 6.0 m³/min reference flow while conveying and operates 18 minutes in each 30-minute window. Time-weighted conveying flow is 3.6 m³/min before purge, leakage, startup or other states. The source still must satisfy 6.0 m³/min while active.

41 — Worked Example D: Shared Lines

Illustrative only. Line A requires 5.0 m³/min and Line B 4.0 m³/min. If process logic proves they cannot overlap, the simultaneous case is not automatically 9.0 m³/min. If overlap is possible, assess the combined case at corresponding pressure conditions.

42 — Required Asset: Dilute Phase Interface Schedule

Record material and throughput basis, conveying mode, route revision, pipe ID, feeder, receiver/filter condition, validated pressure-flow requirement, flow reference state, local conversion where needed, air quality, temperature, operating states, simultaneous lines, source candidate, connection losses, instrumentation, acceptance evidence and unresolved items.

43 — Acceptance Boundary

Verify that the air source delivers the validated pressure-flow requirement at the agreed interface during the defined conveying state and that the process achieves required solids throughput and product condition. Package outlet pressure alone is insufficient.

44 — Measurement Plan

Define pressure locations, flow reference condition, solids throughput basis, filter differential pressure, feeder state and timestamps. Synchronize data where diagnosis depends on interaction.

45 — Commissioning

Confirm material and route revision, source configuration, treatment, valves, feeder and receiver readiness. Air-only checks are preparatory; verify loaded conveying under approved process condition.

46 — Supplier / Specialist Evidence

Attach the source of the validated conveying duty: vendor calculation, pilot test, OEM data, commissioned baseline or other qualified evidence. Record revision and conditions.

47 — Bid Normalisation

Compare candidates on the same delivered pressure-flow point, reference basis, air quality, duty cycle and scope. Identify quoted flow basis and included auxiliaries, treatment and controls.

48 — Energy Comparison

After technical eligibility, compare supported electrical input or site specific-power evidence, actual schedule and control behaviour. Include blower or vacuum-pump power when those are alternatives.

49 — Reliability and Continuity

Define consequence of source interruption and required response. Redundancy, standby or temporary connection should be project-specific; spare compressor capacity elsewhere does not itself guarantee continuity.

50 — Maintenance Interface

Keep filters, coolers, dryers, intake systems, valves and distribution in condition that preserves validated pressure-flow and quality. Source pressure alone can miss a downstream restriction.

51 — FAQ: Can choose dilute phase?

No.

52 — FAQ: What velocity should I use?

Use the velocity supported by qualified conveying design for the actual material and route.

53 — FAQ: Can I size from t/h?

No. Solids throughput alone does not determine gas pressure or flow.

54 — FAQ: Can FAD be used for pipe velocity?

Not directly unless its reference state equals the local pipe state. Convert it first.

55 — FAQ: Does a bigger receiver fix low conveying flow?

Not for a sustained capacity deficit. Storage can support transient demand but must recover.

56 — FAQ: Is higher pressure safer against plugging?

Not as a universal rule. Diagnose material, route, feeder, filter, flow and regime before changing pressure.

Dilute Phase Interface Schedule

• Source Continuity
• Expanded premium edition — engineering depth upgrade

The sections below deepen engineering substance without changing the controlled page identity, map intent or required asset.

Expanded Premium engineering core

Its unique job is to translate the validated dilute-phase design into an air-source interface: required pressure-flow point or envelope, reference condition, connection location, duty schedule, air quality, temperature, turndown and acceptance evidence.

Material and route lock

A validated air duty belongs to that combination. Material grade, moisture, fines, pipe ID, vertical lift, bends, feeder or receiver changes can invalidate the old operating point. The air-source schedule should therefore include material and route revision, not only CFM and bar.

Positive-pressure interface

For positive-pressure systems, distinguish source/package pressure from the validated connection-point pressure and from local conveying-line conditions. Include feeder leakage, local distribution losses, receiver/filter backpressure and the supplier-defined pressure-flow duty. Package outlet pressure alone is not acceptance.

Vacuum interface

For vacuum dilute phase, define suction flow and vacuum at the agreed interface, separator/filter condition, leakage assumptions and process duty. Do not translate vacuum duty into an arbitrary positive-pressure compressor equivalent. Preserve the flow basis and vacuum reference.

Flow reference and local velocity

FAD/standard flow must be converted before division by pipe area. Preserve the worked screen in which converted actual flow of 4.5 m3/min in 100 mm ID gives approximately 9.55 m/s, while explicitly refusing to declare that value suitable for a material.

No universal dilute-phase velocity

Expand the explanation that dilute phase is not defined for every material by one website velocity range. Required transport velocity, solids loading and pressure drop belong to qualified design, OEM data, pilot testing or validated operating evidence.

Pickup and acceleration boundary

Explain how the pickup condition can differ from compressor discharge because feeder leakage, fittings, pressure loss and solids acceleration intervene. Record the design location at which pressure-flow is specified. Do not calculate solids acceleration pressure loss with an air-only formula.

Feeder leakage and terminal backpressure

Treat feeder leakage as a possible source-demand term and destination filter DP as an operating boundary. A clean filter can make commissioning look successful while loaded production increases backpressure. Record normal and governing filter condition.

Duty profile and shared lines

Separate startup, loaded conveying, purge/clear, stop and recovery. For multiple lines, use actual interlocks and credible overlap. Preserve the illustrative shared-line case: 5.0 and 4.0 m3/min lines do not automatically create 9.0 m3/min simultaneous demand if controls prove they cannot overlap.

Storage and recovery

A receiver can support a transient but cannot sustain a continuous capacity deficit. Where a line operates intermittently, verify usable pressure band and recovery before the next event. Avoid using average flow as proof of active source capacity.

Diagnostics

Low throughput: compare solids rate, pressure, flow, feeder speed, filter DP and material condition. High air use: check operating time, leaks, feeder leakage, setpoint, idle/purge and accepted production. Wear: compare bends, material abrasiveness and validated velocity. Product degradation: compare fines/breakage with route and operating condition.

Worked duty-cycle example

Preserve the illustrative case of 6.0 m3/min validated reference flow for 18 minutes in a 30-minute window: time-weighted average 3.6 m3/min before other states, while active source capability still has to meet 6.0 m3/min. Explain why average consumption and instantaneous capacity are different engineering questions.

Source technology and energy

Compare technically eligible compressor, blower or vacuum solutions only after the duty is validated. Include supported electrical input, treatment, control/turndown and schedule. Do not claim savings merely because demand moves from compressed air to another air mover.

Commissioning and acceptance

Verify material and route revision, source configuration, treatment, feeder, receiver/filter condition, delivered pressure-flow at the agreed interface and required solids throughput/product condition. Air-only tests are preparatory; loaded conveying proves the process.

Required asset — Expanded Dilute Phase Interface Schedule

Expand the schedule to include material/route revision, pipe, feeder, receiver/filter DP, validated pressure-flow point/envelope, reference basis, local conversion where required, quality, temperature, startup/loaded/purge/recovery states, simultaneous lines, source candidate, distribution losses, instruments, supplier evidence, acceptance, assumptions and open items.