10 replies to this topic

[ssskharche]

why in most of the refinery we don't produce hyderogen by gasification of coke or from the lpg ?

THANKYOU

[Art Montemayor]

Because either local environmental laws prohibit use of coal or it is not as economical to employ LPG.   In other words, the local value of the LPG is too high to compete as raw material for hydrogen production.

 

Producers will always use the cheapest raw material that is permitted, in order to maximize their final profit.  

[ssskharche]

thanks sir for reply but sir if the coke is formed itself in the refinery in large quantity then also we cant use it

[Bobby Strain]

And that is indeed practiced in a few locations, one of which is in the USA. Try Google search.

 

Bobby

[Mahdi1980]

Hi, 

I agree with Art. The availability of raw material is one of the factors. On the other hand the cost of production and the price of product is the other side of the coin which are highly remarkable.

For instance, the gasification of the coke is a process which can be lead to products like Methanol or Olefins which are most applicable materials and very profitable especially olefines ( Propylene or Ethylene) while Hydrogen as a syngas is located in the middle of the process and the IRR of its production at this stage is too low for investment.

 

Regarding LPG, it is a vital material and it is not logical to convert such a precious substance to hydrogen.

Edited by Mahdi1980, 15 June 2017 - 07:09 PM.

[ssskharche]

THANKS to all sir i got my answer.

[ssskharche]

And sir i want to ask that is there any technical problems other than economical that we cannot opt. this methods.

[Mahdi1980]

No, I don't think so.

[ssskharche]

and also why propane dehyderogenation (PDH) technology for production of propane is not used preferably

[Saml]

Refineries normally have a planning group that have modeled the refinery, the distribution, the logistic at least in a linear model and analyzing the best ways to add the highest value to the oil they are processing with the existing equipment, and the marginal value of adding, revamping, etc, etc different units is their work. So, if the technology is available, there are no regulations that prohibit its use, it is safe, and still is not being used in any refinery you can be almost sure that the reason is economic.

 

A coke gasification unit costs may times what a methane steam reforming costs.  PDH technology is used to make propylene where you have no availability of a catalytic cracker gases as a source of olefins.  But for producing hydrogen it makes no sense.  In some technologies they even burn the H2 with oxygen to shift the equilibrium towards propylene.

[ssskharche]

thank u sir it helped me very much