The most moisture bearing substance in coke is coke fines, more the fines  in coke, more the percentage of  gross moisture content. In other hand, porous coke contains more moisture and porosity  depends on coal cake Bulk density.The coal Blend should be prepared by considering individual coal quality and size of the blended coal to meet the required BD. 

This a complex practical question.

The reasons could be - oscillations the level of readiness of coke, quenching technology (for example, the amount of water on quenching, pouring time, 

time continue wagon with coke under the tower after quenching), time evaporation of moisture on the coke ramp.

Can you please elaborate which method of coke quenching being practiced in your plant.Is it dry or wet quenching?

In a Coke Oven Plant, normally coal as raw material is heated in an airless furnace to a temperature of 1,1000C and above, to remove volatile matter contents, such as, water, coal-gas and coal-tar. After this, the product is quenched either with water or with air. This is in nutshell the process. This micro-description of the process is likely to facilitate further brain-storming process on this problem.

Assuming that the raw material is not much different, as already mentioned by others, the water content will to a great extent depend on the quenching process and further steps towards removal of water from the product. Obviously, water content will be less where air quenching is being used.

For the removal of water from the final product, following methods may be tried.

Please note that the methods suggested are for the removal of water / moisture from the final product of the Coke Oven Plant, namely, Coke. 

These methods are to be considered as separate end-product processing unit. 

The water content in coke can be reduced in coke plant in two ways:

a) the quenching tower with a cellular filling - proven in Polish industry (Attachment),

b) under an inert atmosphere, e.g. nitrogen - it requires construction of huge power supply unit except the coke oven

best regards,

A,

Mianovski's (AM) suggestion (b) is plausible. Here inert gas, namely, nitrogen is required to be used as the atmosphere during the carbonisation and, probably, also its flow through the kiln for the quenching purpose. Please do correct me if my understanding is wrong.

The first suggestion, that is, way (a) is not really clear. Would you (AM) please let us know a bit more (if permissible) about the cellular filling. Based on the observation of the drawing / image included in the attachment I got the impression that the cellular filling is for achieving uniform cooling effect during the process of quenching with water. Is it so ? Unfortunately, I could not read the attached publication.    

Dear Ashis!

1. The quenching in cold nitrogen takes place outside the coke oven ('s) and heated nitrogen is used energetically.

2. Wet quenching of coke in the packed towers with cellular packing is not my idea. The water content in coke is in the range of 1-2%. I will try to find English version of the text about this issue from the authors

best regards

A,.

Dear Andrzej,

Thanks for your reply and for the correction.

I will be glad to read the text in its English version.

With regards,

Ashis

Maybe add a vacuum suction fan or increase the suction if there already is one?

Sorry, I do not know this method in petrochemical industry (petroleum coke) or in coke oven plant. The applicability depends on the scale of coke production (or pitch coke).

with regards

A,

I send the promised text on coke quenching towers containing a bed of cellural packing from PMT MULTICON (Gliwice).

with regards

A,

Dear Andrzej,

Thanks for the downloaded article. I am going through it.

With regards,

Ashis

yes

Dear Makesh, I' sure that only wet quenching of coke in the packed towers with cellular packing will bring a steady water content in the range of 1-5%. More details in the company: www.multicon.com pl      or e-mail:  [email protected] 

Regards: A,

Show prof. Mianowsky sugesstions.

Useful Link

nptel.ac.in/courses/103107082/module2/lecture2/lecture2.pdf