Industrial

[suny]

Hi Everybody

One of my friends has a Block Ice Plant having a capacity of 350 x 50 Kg for a day. I have no experience in Ammonia. Can anyone let me know the followings:

What is the desired Brine Temp
What is the Brine density
What is the SST
What is the condensing Temp
What is the cooling tower water Temp
What is the 1.25” diameter evaporator pipe length per 50 Kg.Best regards
Suny

[Samarjit Sen]

Hi Suny,

What is the capacity of the Block ice you propose to make per day. Secondly do you want to go in for an atmospheric type Condenser which is prevailent in our country ie. bare MS tubes kept in the open with trickling over it and falling into a sump.

Further you can have the Block Ice Making refrigeration plants with R 22 system. We have installed a number of them.

The information desired by you will be provided to you once I get the above datas.

[suny]

Dear Mr. Samarjit

Thank you for the quick reply. This is one of my friends Ice Plant. It is already in production. One technician has installed un matching equipments for him. At present it does not give the desired production quantity of 350 x 50 Kg blocks per day. The condenser is a MS bare tube open into the air to which water is circulated through a pump and fall on the tube which drops back to the sump as in your country.

At the moment he is getting 350 blocks of production in 32 hours. I have no experience in Ammonia. As the basics of refrigeration are same I thought of helping him where he has gone wrong to overcome the present situation. That is why I requested the forum to give those data which will help me to access the problem.

Furthermore as per your request the capacity of the blast freezer is 350 Kgs per 3 hours excluding loading & defrost time. If you need any further info pls do not hesitate to contact me.

Best Regards
Suny

[Samarjit Sen]

Hi Sunny,

Can you please give me the dimensions of the each ice block. That is the height, width and depth.

I have all the datas as required by you, but need these informations so as to provide you with the correct ones.

[Samarjit Sen]

Hi Suny,

You have to wcuse me for the delay in giving the details as required by you. I have got the details and have been using the same. Now that I wanted to give it to you, I am unable to locate as to where I have kept it. Kindly allow me a couple of days , by when I shall locate the informations and have the same sent to you.

[US Iceman]

Hi Samarjit Sen,

I would be interested in seeing this also. I had the opportunity to work on an ammonia system in a very old block ice plant, but have never designed one.

Your information would be helpful in that regard.

Thanks.

[Samarjit Sen]

I have scanned the relevant documents and am attaching the same. Hope this will be of some help to you. Sorry could not upload as the limit is only 100 kb and the file is about 3.6 MB.

Could you please send me your e mail id so that I can mail it to you.

[Samarjit Sen]

Hi US Iceman,

Could you please send me your e mail i.d. so that I can send the Ice Plant documents.

[Samarjit Sen]

For Ice manufacturing you must have seen that bare tube Condensers are being used even now. Can,t Evaporative Condensers or shell & tube condensers used for ammonia. I am sure the performance of the plant shall greatly improve and the power consumption shall be reduced.

[US Iceman]

Can,t Evaporative Condensers or shell & tube condensers used for ammonia. I am sure the performance of the plant shall greatly improve and the power consumption shall be reduced.


I prefer evaporative condensers over other types of condensers for the following reasons:

I believe the piping costs are lower for evaporative condensers than shell and tube condensers with cooling towers.
The condensing temperature is lower than other types of condensers using normal ambient weather conditions as the heat sink.
In cold weather you can run an evaporative condenser dry, but you cannot do this with a cooling tower.
I also believe the initial equipment costs are lower.Atmospheric condensers are old school technology that were being used over 100 years ago, or more.

[Peter_1]

I have scanned the relevant documents and am attaching the same. Hope this will be of some help to you. Sorry could not upload as the limit is only 100 kb and the file is about 3.6 MB.

Could you please send me your e mail id so that I can mail it to you.

Samarjit Sen, can you mail this once to me so that I can post it on a bigger server.
As we have seen many times, you allways have valuable information.

[Samarjit Sen]

Hi Peter !, I will certainly mail the complete chapter which is about 8.5 MB. But the problem is that I can not upload it on the forum. Please send me a PM intimating your e mail id so that I may mail it to you.

[Samarjit Sen]

Hi Suny,

What is the progress in your Ice Plant. Other than ammonia, yu can have ***** based refrigeration plants.

[suny]

Hi Samrajit

My friend is interested in NH3 and not with *****. He says NH3 is cheaper.

I have advice him to correct the errors of the existing plant of 350x50Kg/24 hrs. What will be you all’s opinion to install a pre cooling water tank to fill water to the cans through a can filler. The brine water of the ice plant will be circulated through the pre cooling water tank to reduce the temperature to 25 deg C from ambient to increase the production capacity by 35%. The condensing temp is 36 deg C.

My questions are as follows:
1. Is it necessary to increase the capacity of the compressor by increasing the motor pulley? (Option available to increase by another 200 RPM with larger motor)
2. Can we use the existing rpm to pre cool the water.
3. Can we increase by atleast by 25% from the present production capacity?

Suny

[Samarjit Sen]

Hi Suny,

Sorry I somehow missed your mail. Before I suggest anything, would you please let me know the following.

1. Compressor make, model and the rpm at present.

2. The total length of the Cooling Coil and the diameter of the same.

3. What is the brine temperature being attained at present.

At couple of plants, I had incorporated a smaller refrigeration unit to bring the temperature of water being filled in the cans to 7 to 10oC. That had improved the timing of freezing, thus increasing the production. Do not add any more cans.

[US Iceman]

I think you would have more benefit by using a seraprate small refrigeration system to pre-cool the water.

If you use the brine from the tank this adds to the load of that compressor, which you want to use to freeze the water.

Any extra loads you place on the ammonia system affect the total system; compressors, condensers, etc.

The separate refrigeration system will have a lower overall impact on the ammonia system.

[Samarjit Sen]

Mike you are absolutely correct. I had done this to a couple of ***** Ice Plants. Their performance improved. If you utilise the same unit, it will have an adverse effect.

[suny]

Dear US Iceman & Samarjit

Thank you very much for your advice to have separate refrigeration system installed to pre cool the water. I calculated the cooling load to pull down from 35 to 5 deg C is about 8300 w/hr. Then we can draw 500 liters in 30 minutes. The total capacity of the water tank is about 2000 liters. I also feel that this is a little higher to add to the existing compressor if we draw brine water.

At present my friends is producing 340 x 50 Kg blocks per 24 hr. With a greatest difficulty I was able convince him to remove 20 cans from the tank. As you mentioned he has inserted these to the space allocated for the water circulation and blocked it.

Could you both please advice whether he could unload with in ½ hour if chilled water feeding is done? This will enable me to prepare the feasibility to present him. Further I have experience about this in ice lollies making machine.

Suny

[Samarjit Sen]

Hello Suny,

Please remember that in block ice making the velocity of the brine solution moving through the cooling coil and the brine tank is very important. The agitator must be very efficient and of proper size and there should be suffecient space beteen the cans for the brine to circulate.