deposits in compressor first stage

[cjrcjr]

Hi all. This is my first post, and I'm not sure if I have the right forum - too many seem to be relevant.

I've been out of process engineering for quite a few years (doing petroleum production and HSE). I've recently started back into process engineering as a field engineer and am slowly getting into the swing of things. But I could use some help on this one.

Natural gas from 1st and 2nd stage separators gets compressed from 450 kPa / 34 deg C to 6100-6400 kPa. We are getting 'gunk' dropping out in the first stage - appears to be asphaltenes (according to ops - I haven't seen a lab report yet).

We are operating pretty much at design inlet temp & pressure (102 deg F and 69.60 psia).

I know I need a full analysis of a sample of the gunk and of the feed gas composition, but what else should I look at to help figure out how to solve the problem? Are there chemicals we could inject to keep the asphaltenes from depositing? Do we need to coat the impellers with something?

Any tips appreciated!

Thanks,
Cheryl

 

[Scipio]

Is it dropping out in the first stage of the compressor or in the first stage separator? I don't know of any chemicals that can inhibit the formation of asphaltenes, as far as I know a settling tank is the only way to reduce them. Usually when I've seen them form it's because of mixing natural gas or condensate from two different pressures, once formed, filtering or a tank with a long retention time seems to be the only way to get rid of 'em.

 

[cjrcjr]

The gunk is found in the first stage of the compressors.

My first thought was filters, but I was hoping for chemicals as a short term solution.