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Temp Of Flare Header For Stress Analysis

Mon, 20 Jul 2026 19:36:52 +0000

Dear friends,

I am calculating the actual temperature of the flaring gas from our Vacuum Distillation Tower where a stream of gas (C11H24) at a temperature of 400 C, a pressure of 4.5 barg, enters a flare header with a diameter of 32 inches and a length of 600 meters. Given that the ambient temperature is 48 C, according to heat transfer calculations, on average, the gas temperature drops to 340 degrees at the end of pipe. But this temperature for stress analysis calculations has led to the addition of several loops in the design. Does anyone have any experience in this regard? Isn't the temperature of the pipe wall much lower in practice due to the actual heat transfer with the environment as well as radiation, for example, below 200 degrees? If the temperature drops more in practice , the number of loops caused by the stress analysis calculations will really decrease. I would like to thank you for helping me.

Araboni

How To Size A Presure Equalization Line For A 10" Pipeline Valve

Tue, 14 Jul 2026 13:44:10 +0000

HELLO EVERYONE,

SO BASICLY WE WANT TO SIZE A PRESURE EQUALIZATION LINE FOR A 10" PIPELINE VALVE (KIND OF BY-PASS) TO EQUALIZE THE DOWNSTREAM OF THE 10" VALVE DE TO A VERY HIGH DP BETWEEN UPSTREAM AND DOWNSREAM OF THE VALVE.

THE PIPELINE CARRY A 85 BAR LPG.

Vacuum Total Condenser With Flooded Surface Control During Turndown

Thu, 02 Jul 2026 12:31:58 +0000

Hi everyone,

I am designing a total condenser operating under full vacuum conditions. The process involves steam entering the shell side at 165°C and leaving as condensate. The tube side uses a process gas as a coolant (80,000 kg/h) in a U-tube bundle (2 passes). The exchanger is relatively "short and fat" (approx. 1000 mm length x 740 mm diameter), in BXU configuration.
The main challenge is the very low steam flow (5,000 kg/h) relative to the s&t size, which creates significant hydraulic distribution and duty control issues.
I have tested these configurations
1. BXU: Pressure drop is concentrated 100% in the inlet nozzle. The bundle is hydraulically "transparent" (approx 0.3 kPa in the cross). This clearly violates the rule of thumb of bundle pressure drop > 66.7%of the total to ensure flow uniformity. Without this resistance, I am concerned about a localized "rain effect" directly under the nozzle, leaving the rest of the 1-meter bundle ineffective
2. BJ21U: Similar results. Despite the divided flow, the longitudinal velocity is too low to "activate" the bundle hydraulically.
3. TEMA BGU :This configuration performs better regarding distribution because the longitudinal baffle and the required path force a higher internal resistance.

The system uses Flooded Surface Control (varying the condensate level to adjust active surface area).
For a BGU design, the longitudinal baffle must be continuously welded to the shell. Does this create excessive thermal stress risks in vacuum service, or is it a non-issue for a 1-meter shell?
If I still use a Type X , is the combination of an Annular Distributor (Vapor Belt) and a perforated Distribution Plate (min. 20% open area) considered reliable enough to satisfy the 2/3 Rule and distribute vapor over such a short bundle?
Given that the BGU uses segmental baffles (even with 12 mm drainage notches), is the condensate level control as linear and stable as in a Type X, which provides a perfectly flat free surface?
In the worst-case clean turndown, what measures would you recommend to mitigate water hammer risks in the presence of low-pressure vapor?

I would appreciate insights from anyone who has dealt with this type.of vacuum condensers and the trade-offs between cross-flow and split-flow hydraulics. Is type G suitable for this case? I have to evaluate the submerged area during the turndown? Would you still make a Type X or Type J with a vapor belt and perforated plate instead of a Type G? Although with vapor belts the situation in terms of DP would not improve much?

Thanks a lot.

Slotted Pipe/diffuser Design

Thu, 02 Jul 2026 12:10:49 +0000

I need to design a Concrete Thermal Energy Storage Tank with Slotted Diffusers

The Process parameters are as follows

Flow: 10700 usgpm (Fluid: Water)

Temp in / out : 3.3 / 13.3 C

Internal tank dimensions : 14 m x 14 m x 42.5 H

There could be an H shaped or a octagonal shape diffuser with slots. The length of the diffusers (top and bottom) can be adjusted.

I need advise from fellow engineers, if any one has any calculation/references to calculate the dimensions of the slots (WxLxDepth), in-order to maintain very laminar flow/low velocity so that the thermocline thickness is not disturbed through out vertical length while charging and discharging. Or there is a dimensionless number such as Froude no or so which can relate to the slot design.

Thanks

Instrument Air Dryer

Mon, 29 Jun 2026 16:09:14 +0000

Dear Team members,

Instrument air dryer uses adsorbent Alumina for removal of moisture designed for 100 % humidity & 45 Deg C With lower humidity and feed temperature at 35 Deg C whats is impact on performance respect to dew point and capacity of the dryer.

With regards

Tsv Set Pressures

Sat, 27 Jun 2026 08:33:26 +0000

Dear Gents,

In our product transfer unit TSV are provided on transfer lines from Tank to loading bay. TSV set pressures 12 bar are observed to match the pumps shut off pressure when operated at minimum flows.Now we need to reset the TSV set pressures,as observed frequent activation leading to maintenance.Whats should be the revised TSV pressure .considering no change in pump operation.

Thanks

Nitrogen Flow Meter Dp Type Error

Thu, 18 Jun 2026 07:47:15 +0000

Dear Gents,

For the nitrogen flow measure ment we have DP type transmitter having range 0-2500 MMWC ,variance ,diff between custody meter which is ultrasonic is observed at a lower flows < 1000 Nm3/hr . With current DP what are the options for reducing the difference

Design Of High Temperature Duct Work

Tue, 16 Jun 2026 00:08:05 +0000

We have set up a moderately sized pyrolysis pilot in East Africa using some off the shelf technology. The reactor consumes about 250 kg/h of dried sugarcane bagasse and pyrolysis gases are combusted in a "chimney" box above the main reaction zone.

We have a short run of duct exposed to high temperatures coming off the reactor, as we draw the fully combusted flue gases at 650C to be used for direct heating of wet biomass in a rotary dryer. We're looking to replace and improve on the current duct design but are struggling to find good references on standard best practice or heuristics for hot combustion gas handling; we don't want to reinvent what must have surely been solved. Thus far, we've been unable to find unambiguous best practice for this type of service.

However, we are are considering using ceramic fiber blanket to insulate the internals of the ducts. I am hoping the forum can sense check this approach, or if there is a practical alternative that industry uses (our next best option is just to go straight to a stainless steel, but this will also creep over time).

I appreciate any advice or direction that can be given and we'd be happy to share more information.

Ai For Designing Of Process Plant

Sat, 13 Jun 2026 01:59:45 +0000

Hi all ,

Do you any AI which can be used to prepare all process engineering documents . If yes which AI is to be used any specific refence if any body have used .

"natural Gas Co2 Removal Via Membrane Separation

Thu, 11 Jun 2026 00:28:16 +0000

Natural gas CO2 removal via membrane separation: The feed gas enters a shell-and-tube heat exchanger to be heated to 35°C by hot water before entering the 1st-stage permeation membrane. The separated permeate gas is compressed and sent to the 2nd-stage membrane separation, after which the retentate/residue gas is recycled back to the inlet, while the 2nd-stage permeate gas is sent to the generator set for power generation. Is anyone familiar with this P&ID? Are there any control flow diagrams available? I would like to study which points require enhanced control