Converting the Specific Gravity of Water

mavrick22c,

There may be a table somewhere. I doubt that it would have densities of saltwater at more than a couple of different temperatures (probably just one - 20 or 21ºC). Try the CRC Handbook of Chemistry and Physics. It is found in the reference section of most libraries.

Mike

141.5

API=--------- -131.5

sp gr 60F/60F

for gas is air

for liquid is water and i want sp gr water in 60 F?????????????????????????????/

Some links I've seen on a snow and ice forum:

http://seagrant.oregonstate.edu/sgpubs/onlinepubs/h99002.pdf

http://www.iowadot.gov/maintenance/internetpages/chemicals/index.htm

Not exactlly what you're looking for, but maybe a jumping-off point in the right direction?

Maybe a salt producer or a salt-water fish store could help out some?

I appreciate your info on electrical conductivity (EC) and its relationship with NaCl when dissolved in water (which I was aware of but definitely not to that extent) but the only tools I have are:

1.) 1000 ml beaker

2.) Hydrometer set (Specific Gravity calibrated at 60F)

3.) Thermometer

And the water sample comes out of a natural gas well between 110 – 120F. I allow it to cool 75F and then drop in a hydrometer to determine the specific gravity. With this information, I reference a chart to determine the Sodium Chloride content in the sample. Testing for the level of NaCl content can determine the "health" of the well.

The reason I am looking for the formula to convert Sp. Gr. is that I have recently discovered that the chart that I am using may not be very accurate and I would like to create a new one in Excel. I also want to be able to enter any given temperature. I have everything set up in Excel except one vital component, the formula to convert Sp. Gr. to NaCl mg/L

Hello vincenzo, you sound like me not trusting what charts you use. Especially importation if you use wikki as they can be edited. You may have already done this, but, you can start making a chart by measuring you well water every degree it cools from boiling to see if there is any difference. Do the same with distilled water and see the difference also. Sorry I have to go but, you have the stuff tesser gave you and the sights and definite way of working things out. You just need to focus now. that, and buy another couple of beakers and an evaporator? Good luck and keep in touch.......................

Hello mavrick22c:mavrick22c:mavrick22c:mavrick22c:

My punishment, must write 1000 times your name is mavrick22c! Not vincenzo!

Sorry Mavrick22c, I was trying to sent a lot of short posts and sent you one with another correspondents name. Please forgive me? It was at a time I was getting the IE freeze repeatedly, and was trying to rush to send as much as I could before the next crash!

Sorry once again.

Take care and good luck..................

Not a problem at all. I simply thought you were referring to someone else. As for your IE issues, why not try Mozilla Firefox? I'm extremely prejudice against IE.

Hello mavrick22c,

As for your IE issues, why not try Mozilla Firefox? I'm extremely prejudice against IE.

With regard to this I was thinking of either getting a cheap laptop or, even a mac rather than have these constant problems. That I could handle, it is when you have to 'jump through loops' on the Microsoft site, then they just send you round in a circle? You end up back at the same page after following their advice.

I really need another computer to allow me to get this one back to A1 condition. I have XP on it at the moment but I can always get Firefox.

What has your experience been with Mozilla/Firefox?

Take care................

You can buy a TDS meter for about $15.00.

The NaCl content is approximately 17 per cent. If you want a more exact figure, weigh a known volume sample of the solution (say 100ml) and evaporate to dryness. you should then have around 17 grams of solids left.

Sorry, but that was not the question. That was just an example. You are correct though. I also carry with me a refractometer. It tells me the %NaCl in the sample and with that I can calculate the mg/L but the refractometer does not give me the level of accuracy that I am looking for.

tesser,

That was my first thought exactly. My mind went right to Perry's Handbook page 3-83. For some reason after almost 20 years I still know what page that information is on (Sixth Edition). GA

Hello tesser,

GA to you for such detailed info'!

I think this solution awesome, thank you.

Hello prof vincenzo!..........

So how are you working it out?

A liter of pure water weighs 1000 grams. A liter of your solution weighs 1125 grams. Wouldn't there be approximately 125 grams (125000 mg) of salt in a liter?

No, the temperature also plays a large role in the equation. Your answer would be true if the sample was 60F.

From Perry

Tad

Hi Guest,

I think you are confusing the specific gravity of water with the amount of salinity.

Take care

Not confused.

The specific gravity of a liquid varies with many other things apart from the salt content, like the alcohol content for example, so SG-to-salinity is not the best way to do it.

Conductivity-to-salinity (at a fixed temperature) is a lot easier, and there are a number of previous discussions in CR4 on the topic.

There is an article on the salinity of seawater in Wikipedia [other on-line encyclopaediae are available], which might be of interest, perhaps?

Hello PWSlack:,

I appreciate the info, thank you. It is not my thread but, I think it is pretty interesting!. Thanks again..............

Take care..................

Let me explain once more. This time, in more detail. When oil/gas companies search for reserves, they look for salt caps using seismographic data because most oil reserves all old sea beds. After they find a nice place to punch a hole in the ground, they do just that and then "frac" it. This involves pumping anywhere between 30k bbls (1,380,000 gal.) to 160k bbls (7,360,000 gal.) of fresh water down into the well. Mixed in the water is a large part sand plus a small part various chemicals (no alcohol) to reduce friction as the mixture travels down the well. When the process of "completion" is done, then the well is ready to open. This is where my job comes in. Because they pump so much water down the hole, it's basicly a water well when we first open it up. My job is to get this water out of the well so the gas can make its way up. Some flow water on thier own until the gas hits, some need help and may flow water for weeks until they hit gas. The entire time I'm out there trying to get the well going, I collect a large amount of data to send off to the gas company each day. Amoung this data is salt content or "chlorides" (as they say in the oil field) or salinity. How ever you wish to call it. The amount of salt content in the water can tell a person the health of the well. The Barrnett Shale (Name of the underground formation or layer of rock that contains the gas) is in between two auqifers. A freash water one on top (can't recall the name at the moment) and a salt water one below (Ellenburger.) If they frac into either of these, depending on how sever, could render a well useless and goes about $2.2 million down the drain. (The idea of it all is to get the water OUT of the formation.) 60,000 ppm to 80,000 ppm This is a good sign that the salt is mostly coming from the salt cap or salt in the formation. Too low means may have tapped into the freash water table. Too high means may have tapped into the salt water table.

Hi Guest,

Appreciate the detail, thanks.

The problem is, if the 'Trinity-Woodbine' aquifer is hit or it collapses there is a serious problem to the supply of fresh water to Texas!

Thanks for your post.

Take care

Okay... I'm not seeing how that applies to anything I've mentioned... maybe I missed something...

Hi Guest,

That was the name of the fresh water aquifer under a good chunk of Texas, which you said you could not recall the name of?

Or have I got this totally screwed?

Take care.