2 replies to this topic

[Brijesh Hirani]

How to start the material balance and energy balance Of The Entire Ammonia Manufacturing Plant? The Capacity Of Plant Is 1200 Tons Per Day

[Art Montemayor]

You do it by using the principle of "divide and conquer".  First, balance the mass and energy that is entering and exiting the total plant facility; then, start to "divide" by going to the first unit where your raw material(s) are entering and you make a balance there.  Subsequently, do the same on all units both process and utility services.  Some units will be Unit Operations (physical changes take place) while others will be Unit Processes (where chemical changes - or reactions - take place). 

[TS1979]

First start from the easy part - mass balance. To do the mass balance for the whole plant, you first need to create a process flow diagram (PFD) to include all major equipment. Try to identify which line has flow meter, analyzer. Based on these flow rates and compositions, see if you can get the mass balance done. If can't, you need to get the conversion factor and assume some flow rates and compositions based on your knowledge. Always using mass flow for your stream to simplify your mass balance calculation.

 

For compressible gases, energy balance for the whole plant may be a too complicated task to be completed.