I does not mean that it is " Yeast " , it was typo error sorry for inconvenience ; instead of Yes I wrongly type yeast . My querys is that if our reaction requires some temp ;  so can we consider the heat generated during mixing of liquid by agitator -which upcourse requires power while considering heating requirment .  Power required by agitator  can be considered (as temp will  rise in slurry/liquid due to agitation ) while considering heating requirement of that reactor . Suppose tank is having heating coil; so temp rise due  to agitation in slurry can be considered while calculating heating requiremen. 

Suppose heating requirement is X and heat genereated due to agitation is Y so while designing heating requirement i.e.

Net heating requirment  for designing coil = X-Y .

SO3 is produced by conversion of the So2 to So3 in a convertor. DP for the 1 st and 4th beds has observed to have increased from the normal values to max limits .Is their a tool to predict the balance service period of operation based on DP. flow has been reduced by 20 % of cap.

Nitrogen is generated by passing compressed air in a pressure swing adsorption cycle. The adsorbent used is Carbon Mol. seive. Mechanical tests, namely Crush strength and Hardness, are required to check its performance.

Requested members to share the standard test methods document.

Hello everyone,

I would like to understand how to convert packing height into an equivalent number of theoretical trays, and vice versa (i.e., number of trays to packing height).

This is for an amine plant I am currently working on, and I am trying to evaluate which option would result in a more optimized design—trays or packing.

I would appreciate any guidance or references on this topic.

I am currently designing a cold vent (atmospheric flare/vent stack) for a high-pressure gas pipeline system operating at 70 bar.

One of the key design parameters I need to determine is the minimum required distance between the blowdown valve and the vent outlet.

Are there any specific standards in teh API 521 ( which i didn't find so far ) 

So are they any good practice to properly size this distance,

Thanks in advance.

I’m operating a chemical plant and we recently started producing about 3 tons per batch of potassium silicate solution. (90% KOH + H2O +  precipitated silica99% )

After production, we immediately rinse the tank thoroughly with water (right after discharge, before any visible drying). When the tank surface is still wet, it looks completely clean.

However, once the tank dries, we consistently find a significant amount of white powder residue on the inner walls. This residue is quite difficult to remove and requires additional cleaning effort.

We are planning to use this tank interchangeably for both potassium silicate production and cleaning agent manufacturing, so this issue is becoming a serious operational concern.

My questions:

1. Is this a common issue in potassium silicate production?
2. Is this likely due to silicate film formation or silica precipitation during drying?
3. Do most plants use acid rinse or other methods to prevent this?
4. Is it realistic to use the same tank for silicate and detergent production?

Any advice or shared experience would be greatly appreciated.

Thanks in advance!

• Tank Capacity : 2500 m³
• Tank Internal Diameter : 17.2 m
• Height : 12 m
• Liquid_in : 286.1 m³/hr
• Flash point : -43 ^oC

What I've done is calculate the capacity of N2 using API 2000 for inbreathing,

• Q_{inbreathing liquid} : 268.9 Nm³/hr
• Q_{inbreathing thermal} : 422.5 Nm³/hr
• Q_total : 691.4 Nm³/hr = 0.19 Nm³/s

After that, using "Rules of Thumb for Chemical Engineers By Carl Branan"

• Suggested Fluid Velocity N2 (Air = 78% N2) : 4000 fpm = 20.32 m/s
• Typical Design Vapor Velocity (Gas or Superheated Vapor 0 to 15 psig) : 50 - 145 ft/s (pick 65 ft/s = 19.8 m/s so < 20.32 m/s)

After that, 

• A = Q / v = 0.19 / 19.8 = 0.0097 m²
• D = SQRT(4 x 0.0097 / PI) = 111.13 mm

Then with SCH 40 that satisfied the D and common in the market is 6" (154.05 mm)

Does my calculation is correct? 
If wrong, can someone please explain the other way to calculate it because after read the API 2000 that is what I thought.
Thanks in advance !!

On discharge line PSV is provided for a set pressure of 1.3 barg whereas the Separator design pressure is 14 barg.We have strainght guideline in API for single phase check valve failure case but not for Two Phase.Can you please guide how to estimate relief load.

1. The desalted pump suction pressure dropped below the design value, hence low discharge pressure

2. High HFO temperature to the cooling water box

3. Increased pressure at the fractionator overhead.

We have shut down the plant to run on cold recycle and system depressurised  but challenge resurfaced 8 hrs after heating up at a nominal value. 

The product yield is fine but the inability to ramp up rate has been a concern. What could be the challenge? I will appreciate a good insight into this.