I did a search on cement plants at this list and it made for
interesting reading. But I didn't see what kind of cars were used to
ship the raw gypsum to the plant. Would these be open top cars--
gondollas and hoppers? And, if so, is this a very heavy comodity,
i.e., if open top hoppers are used, they would be loaded well below
the car line?

I'll modeling a cement plant on the end of a branch and am having
the gypsum shipped in from another location on the mainline under a
hundred miles away from the cement plant (proto freelance, Wabash
early 1950's). I would assume the cars would mostly be of the
originating road's cars and probably not too far away, since Gypsum
is readilly available all over the Midwest? Could these be cars used
for other service or would they be dedicated or downgraded cars?

I was thinking that in addition to inbound gypsum, box cars would
bring in packaging material like barrels and bags. Also, there would
be inbound coal in open top hoppers and empty covered hoppers for
outbound bulk cement and empty box cars for outbound packaged cement.
Somewhere along the line I saw something to the effect that tank cars
of some type of chemical fit into the equation. And how about
byproducts or refurse from the Kiln process or the shipment of Kiln
components on a flat car?
Victor Baird
Fort Wayne, Indiana

Victor, the vast majority of gypsum is to make plaster which in turn is used
to make wallboard. Today, maybe 15% is used for cement. Dunno about other
roads, but the post WWII the Western Pacific took several old boxcars and
added small doors on the roof for loading. The interior car height was under
8' so it was a good use for a small car.

Factoid-of-the-day: the average U.S. home has 7.3 metric tons of wallboard.

Dave Nelson

Victor Baird wrote:

I'll be modeling a cement plant on the end of a branch and am having
the gypsum shipped in from another location on the mainline under a
hundred miles away from the cement plant (proto freelance, Wabash
early 1950's). I would assume the cars would mostly be of the
originating road's cars and probably not too far away, since Gypsum
is readilly available all over the Midwest? Could these be cars used
for other service or would they be dedicated or downgraded cars?

Perhaps there are sources of low-grade gypsum around the midwest that are
usable in cement, but the only good sources of the stuff in the US I'm
aware of off the top of my head are the appropriately named Plaster City,
California and Gypsum, Colorado. Someplace in Canada too. And almost all
of that gypsum goes into wallboard. But yes, most inbound stuff will be
loaded in cars from the originating road unless that road just happens to
send back a lot of foreign cars your way. Then they'd use the foreign cars
for the backhaul, per AAR interchange regs.

Powdered gypsum weighs about the same as powdered Portland cement
(~70#/cuft). So it would travel in the same cars, smaller 2-bay covered
hoppers and/or bagged in 40-foot boxcars.

Isn't gypsum added to cement to regulate the curing time? Is it added to
all cements? I thought it was only in some. And in any case its
percentage by weight is very small. Cement is mostly dehydrated limestone
with trace minerals added, so most cement plants are located right next to
a limestone quarry. While sizable tonnages are shipped by rail, the profit
margin is always low so you don't want to ship it any farther than
necessary, and that lends itself to trucking. In other words, your
midwestern cement plant won't be shipping its product to California.

I was thinking that in addition to inbound gypsum, box cars would
bring in packaging material like barrels and bags. Also, there would
be inbound coal in open top hoppers and empty covered hoppers for
outbound bulk cement and empty box cars for outbound packaged cement.
Somewhere along the line I saw something to the effect that tank cars
of some type of chemical fit into the equation. And how about
byproducts or refuse from the Kiln process or the shipment of Kiln
components on a flat car?

There's five basic types of Portland cement, but most plants only make a
couple and most batch plants only supply two or three. Today almost all
cement that is shipped by rail goes in covered hoppers (3,000cf 100-ton
cars), but back in the '50s a fair amount was probably still bagged at the
plant and shipped in boxcars.

In addition to limestone, to make regular Portland cement you need small
quantities of alumina, silica, iron, and carbon. Kaolin clay supplies the
alumina and silica, other clays or good old rust supplies the iron, and the
soot from the fuel that fires the kiln ("kill") supplies the carbon.
"White cement" like that which made Medusa famous has little or no iron or
carbon.

Low grade deposits of kaolin in southern Minnesota are used in cement.
Otherwise, most kaolin comes from the southeast. Ball clay, a relative of
kaolin, can also be used. Note that you do not need high grade clay for
cement, and today that Minnesota kaolin is hauled in gondolas. Loading any
loose powder in a boxcar will render it "low grade," suitable only for
unimportant cargoes until it is thoroughly cleaned and probably re-lined.
About the only thing worse is to load a boxcar with fresh hides.

Tank cars can bring in fuel oil or heavy waste chemicals that are
convienent to burn (dispose of) in the high heat of the kiln. But most
cement plants burn either coal or natural gas, so you won't see tank cars
at them.

The only "refuse" from the kiln is "clinker." Clinker is raw portland
cement, and IS the product of the kiln. The clinker is stored in heaps
under sheds until needed for shipment, then is ground up and mixed with a
little gypsum which makes the powdered portland cement we're familiar with.

Rotary kilns are big things that are shipped in pieces to the plant when it
is built, then assembled in place. But they last a long time (decades), so
your plant won't be receiving too many kiln parts while it's in operation.

Scott Chatfield

Scott Chatfield commented (as part of a nice summary):

Isn't gypsum added to cement to regulate the curing time? Is it added to
all cements? I thought it was only in some. And in any case its
percentage by weight is very small. Cement is mostly dehydrated limestone
with trace minerals added, so most cement plants are located right next to
a limestone quarry.

Right--and if I remember correctly, limestone (and cement) is largely
calcium carbonate, while gypsum is calcium sulfate (variously hydrated etc.
with some complex chemistry and crystallography, but let's not go there).

While sizable tonnages are shipped by rail, the profit
margin is always low so you don't want to ship it any farther than
necessary, and that lends itself to trucking. In other words, your
midwestern cement plant won't be shipping its product to California.

This is true of several products modelers like to depict: brick, sand,
gravel. All are relatively heavy compared to their value, and the materials
are widely available. Thus ordinarily these materials don't travel very far
from their origins.

Tony Thompson Editor, Signature Press, Berkeley, CA
2942 Linden Ave., Berkeley, CA 94705 http://www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroads and on Western history

Scott Chatfield wrote

Perhaps there are sources of low-grade gypsum around the midwest
that are usable in cement, but the only good sources of the stuff
in the US I'm aware of off the top of my head are the appropriately
named Plaster City, California and Gypsum, Colorado.

FYI, from the now defunct U.S. Bureau of Mines:

" In 1994, output of crude gypsum was 17.3 million tons valued at $120
million, 9% more than in 1993. Leading States were Oklahoma, Iowa,
Texas, Michigan, Nevada, California, and Indiana, which together account
for 76% of total output. Thirty-one companies mined crude gypsum at 58
mines in 19 States, and 13 companies calcined gypsum at 70 plants in 28
States. Of the total supply of crude gypsum ( 26.0 million tons, including
1.1 million tons of byproduct gypsum ), 20.0 million tons was calcined for
gypsum products, and 6.0 million tons was used mainly as cement retarder
or as agricultural land plaster. Calcined gypsum was sold as prefabricated
product or as industrial or building plaster. Sales of gypsum for use in
cement were 3.5 million tons and for agriculture and other uses, 2.5 million
tons. "

Scott, I'm surprised at you; I thought you were a midwestern boy. Surely
you've heard of the large wallboard output from the Ft. Dodge, Iowa area?
Before Mike gets irate because I cited 1994 stats, I will point out that
the Ft. Dodge area was cranking out wallboard in the 1950's. That area is
why CGW and IC at least, had many bulkhead flatcars for wallboard.

Tim O'Connor <timoconnor@...>
Sterling, Massachusetts

Tim O wrote:

Scott, I'm surprised at you; I thought you were a midwestern boy. Surely
you've heard of the large wallboard output from the Ft. Dodge, Iowa area?
Before Mike gets irate because I cited 1994 stats, I will point out that
the Ft. Dodge area was cranking out wallboard in the 1950's. That area is
why CGW and IC at least, had many bulkhead flatcars for wallboard.

For the geographically challenged like Tim, there's a slight difference
between NW Iowa and Northern Colorado (where I'm from). It's called
NEBRASKA.

And yes, the fact they produce(d) wallboard in NW Iowa is news to me.

Now if we can get Tim to tell us the total tonnage of Portland cement
produced in 1994, we could divide that into the 3.5 million tons of gypsum
consumed by the cement industry to figure out the percentage of gypsum in
Portland cement, at least as an average across all types of cement. There
IS a limit to how much analysis we really need to do before we can just run
some trains and spot some cars.....

Scott Chatfield

--- In STMFC@y..., Tim O'Connor <timoconnor@a...> wrote:
-> Scott, I'm surprised at you; I thought you were a midwestern boy.
Surely

you've heard of the large wallboard output from the Ft. Dodge, Iowa

area?

Before Mike gets irate because I cited 1994 stats, I will point out

that

the Ft. Dodge area was cranking out wallboard in the 1950's. That

area is

why CGW and IC at least, had many bulkhead flatcars for wallboard.

Right on Tim. Some days 20 to 30 loads would move east through
Freeport, Il on the IC from Ft. Dodge in the 1950's and 60's. Medusa
Cement Co., in Dixon, Il. would receive gyp rock from Ft. Dodge in
two and three bay hoppers. IC move all the way. CNW got the road
haul in later years.

Chet French

Thank you Tim. Fort Dodge has been mining Gypsum for something like 150
years. Open gons and box cars were the standard freight car used to move the
raw rock to processing plants. Clark Propst (note sp) can give a more
accurate picture of Fort Dodge operations and freight cars used. There is
also gypsum mines in the Fort Madison, Ia area (take note ATSF modelers).

I am noticing a troubling trend on this list and ask for a change. When
discussion moves to industries and commodities most references are to
modern/current operations. If this group is serious about freight cars prior
to 1960 then let also discuss industries and commodities in the same time
reference. As we know freight car design and usage has changed drastically
since 1960, so to has the moving and handling of commodities. As I model
1949, I would appreciate industrial references to 1960 and earlier. Current
practices are of no interest and do not help me determine what freight cars
I should be modeling. Thank You.

Doug Harding
Iowa Central Railroad
www.cal-net.net/~dharding/ <http://www.cal-net.net/~dharding/>

I looked up the USGS site's historical data, and it looks like 1994
domestic production of Portland cament was about 78 million metric tons.
So, assuming that 3.5 million tons of gypsum is also metric tons, that
means on average gypsum comprises about 4.5% of the weight of Portland
cement. This fits with other info sources I've looked at, which give the
gypsum content of Type One Portland cement at about 5%.

Also, if kaolin clay is not used, shale and sand can be used to add the
needed alumina and silicates.

Scott Chatfield

It's probably too recent a development for the steam era, but scrubbing
plants used to reduce SO2 emissions from coal fired power stations
produce considerable amounts gypsum as a by-product.

Aidrian

~
~Perhaps there are sources of low-grade gypsum around the midwest that
are
~usable in cement, but the only good sources of the stuff in the US I'm
~aware of off the top of my head are the appropriately named Plaster
City,
~California and Gypsum, Colorado. Someplace in Canada too. And almost
all
~of that gypsum goes into wallboard.

---
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Doug Harding wrote

I am noticing a troubling trend on this list and ask for a change.
When discussion moves to industries and commodities most references
are to modern/current operations.

Doug, you're welcome to chime in at any time with references
from the steam era. Instead of lamenting the lack of them why
not take it upon yourself to supply them? Unfortunately I have
not been able to find Bureau Of Mines statistics from the 1940's
on the Web, so I cite what I do have. I don't know about gypsum
being mined since 1852 in Fort Dodge as you claim, but the
current operation there was opened in 1908.


Tim O'Connor <timoconnor@...>
Sterling, Massachusetts

Victor,
I will try to do as the boss has directed and copy the questions from
your post. But first, I'd like to say that cement plants of the steam
era bare little resemblance to the modern plants of today. These plants
like most industry then were pretty much self sufficient. Except for
gyp, read no kaolin clay in gondolas. Kaolin clay is a relatively recent
addition to the recipe. Thanks to the EPA and DNR's, this was not a
problem in the time this group is interested in because all the waste
dust went out the stacks.

Now your questions;
Would these be open top cars--gondollas and hoppers?
Yes.

And, if so, is this a very heavy commodity,
i.e., if open top hoppers are used, they would be loaded well below
the car line?
I'd go somewhere between half and three quarters. The stuff looks like
egg shaped pieces of chalk.

I would assume the cars would mostly be of the
originating road's cars and probably not too far away, since Gypsum
is readilly available all over the Midwest? Could these be cars used
for other service or would they be dedicated or downgraded cars?
I only know that in the late 60's the CNW was using down graded cars in
this service. The only true info I have on this time period is of a
couple of FtDDM&S cars. I can look them up if you like.

I was thinking that in addition to inbound gypsum, box cars would
bring in packaging material like barrels and bags.
Cement was sold by the barrel, but not shipped in them since maybe the
20's. Car loads of sacks would be infrequate.

Also, there would
be inbound coal in open top hoppers and empty covered hoppers for
outbound bulk cement and empty box cars for outbound packaged cement
Coal could come in gondolas, depending on the plants unloading setup.
Covered hoppers were a fifties invention (general statement). Most
cement would be sacked and loaded into box cars in the 40's.and early
50's.

Somewhere along the line I saw something to the effect that tank cars
of some type of chemical fit into the equation.
Plant's needed to dry the raw materials, it's possible to have fuel oil
tank cars.

And how about
byproducts or refurse from the Kiln process or the shipment of Kiln
components on a flat car?
Byproducts or refuges was not a problem. There was a great deal of
modernization taking place during the 50's. So it's possible to bring in
new equipment on flat cars.

Hope this helps,
Clark

Isn't Gilsonite used for about the same thing? If so,
the D&SL shipped 8000 carloads a year from Craig,
Colorado until the late 60's. Lets me run LOTS of
boxcars!
Actual STMFC Content Starts here:
Anyone know if Al Westerfield has any plans to make
his Fowler Clones into one piece cars? I need a bunch
for Gilsonite service.

Kevin Slark

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Isn't Gilsonite used for about the same thing? If so,
the D&SL shipped 8000 carloads a year from Craig,
Colorado until the late 60's. Lets me run LOTS of
boxcars!

Gilsonite is unlike anything else. A momment with google produces 3690 hits,
the second of which is:

http://zieglerchemical.com/gilsonit.htm


Dave Nelson

Kevin,

Are you sure about this use for gilsonite? Gilsonite is a solidified petroleum, roughly akin to solid
tar. I can't see how it was used in cement, though it might have substituted for coal in the kiln.

Most of gilsonite from the Rainbow, Utah area went to Mack, Colorado (via the narrow gauge Uintah Ry.
until 1938, and later by truck) where it was refined into high octane gasoline. I didn't know the D&SL
hauled it, though they would have been the closest rail connection to Rainbow after the URY was
abandoned. And although I haven't heard of any other sources, there might have been other gilsonite areas
besides Rainbow.

Kind regards,


Garth G. Groff

Kevin Slark wrote:

For some strange reason, I assume that Tim Gilbert
will be able to answer this, but I'll throw it out to
the group - from where and how would the New Haven
have received shipments of gypsum in 1947? Would this
have come from the Southeast in gons (maybe some of
those really short IH SAL gons)? I know that the New
Haven customers were not huge cement producers, but
there was some that didn't come from the eastern PA,
northern NJ area.

Thanks in advance.

Ted

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http://fifaworldcup.yahoo.com

Ted Culotta wrote

For some strange reason, I assume that Tim Gilbert
will be able to answer this, but I'll throw it out to
the group - from where and how would the New Haven
have received shipments of gypsum in 1947? Would this
have come from the Southeast in gons (maybe some of
those really short IH SAL gons)? I know that the New
Haven customers were not huge cement producers, but
there was some that didn't come from the eastern PA,
northern NJ area.

Uncalcined gypsum, the type used as a cement ingredient, is
produced nowadays mostly in the west and the midwest. But a
fair amount comes from New York State, and Virginia. Only a
conductors' log would tell us how it was delivered to the
New Haven's online cement producer(s). (I think there was
and is an active plant on the Housatonic branch.)


Tim O'Connor <timoconnor@...>
Sterling, Massachusetts