Waste water BS&W procedure

[LPLP]

I'm a consulting engineer helping to get a waste water treatment plant operational. No sewage, just water to clean up. BS&W testing on incoming water is mandatory. Occasionally, totally black water comes in and it is difficult to ascertain a good value of solids content. Certainly, after the test is performed, the water clears up and I can see the aggregate suspended solids plus prior solids, but I want a good number for solids, too. There really doesn't seem to be a good solution to timely determine this. Does anyone have any suggestions on an optimal method for determining solids content of the black water prior to centrifuging?

 

[ashtree]

You can do a test the same as determining MLSS in activated sludge. Put a mixed 100ml sample through a filter paper of a known weight . Bake out the moisture and weight it again. If you subtract the initial weight of the filter paper you can get the weight of the solids accumulated on the paper.
Is that what you are after?

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[GeoEnvGuy]

You can generate a rating curve by measuring electrical conductivity and running a sample for total suspended solids. Common environmental probes measure electrical conductivity but report tss by using a factor of 0.5 and others use 0.33 as the factor.

 

[bimr]

The EPA Standard test will work:

Total Suspended Solids, SM 2540 D – 2011 (SM 22nd edition)

 

[LPLP]

Thanks for the replies. I can tell total solids after centrifuging, no problem. The problem is that if water colored black (not "black water") comes in I can't visually check what the solids content is (solids already settled as opposed to total dissolved solids, suspended solids or total solids). After the BS&W test I get suspended solids + solids (that were not suspended or dissolved to begin with). I need to know what the solids were before BS&W test added suspended solids to the bottom of the tube. This is for water acceptance testing: it needs to happen quickly so trucks aren't waiting for an hour or more for the results to come back. If the water is black I can't visually see what the pre-centrifuge solids volume is.

ashtree: I like the idea but for the baking time. Trucks can't wait that long.

 

[ashtree]

Okay then. Do the MLSS test as described above and make sure you suck as much through the paper as possible with the vacuum flask/pump. Then weigh it wet. This is not going to get you a accurate number. But if there is a lot of soliods it will weigh much more than if there is only a little amount. You may also be able to visually see the difference. It would be worth testing a few samples to test the theory.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[LPLP]

Yes, I've been circling around something like that. Time to start experimenting. Thanks for the suggestions!