Update On Snow Shed

The humid weather we have been having lately is causing adverse effects on the urethane casting resin. I have ordered some new types of resin from Smooth-On to see how they work. Have added a dehumidifier in the work shop unfortunately it raises the ambient temperature causing the resin to catalyze to rapidly. New resin has a longer pot life and slower set time.

David

1897 Niter Storage Building

The final building associated with the sulfuric acid plant is the salt peter storage shed. It is a single story building with 9 foot eaves and is 15' x 12' in size. It should be noted that this building is set apart form other buildings in this complex. This is due to the explosive nature of the product being stored.

A Google Book Reference

http://books.google.com/books?id=uRJDAAAAIAAJ&printsec=frontcover&dq=a+treatise+on+chemistry&hl=en&ei=HZhXTKbEMNC2ngfK54CcBA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CC0Q6AEwAA

The above link is to a Google book (A Treatise On Chemistry) that gives a very good review of the chamber process for creating sulfuric acid. The description begins on PDF page 440. It is contemporary to the time period and has several illustrations of the manufacturing facilities. I have reviewed several other period references and they are essentially the same in there descriptions of the manufacturing process. My continued discussion will utilized the information learned to make educated guesses as to how these buildings looked as I have not been able to locate any photographs of the Carbon Works.

David

1897 Chamber Building

The acid chamber building is 190 feet long and 72 feet wide with eaves 32 feet above the ground. There is a raised roof 8 feet wide and 3 feet high at the peak and it is indicated that the structure is 3 stories tall with the first story empty. A single story 18' x 50' office and engine room with eaves at 12 feet is on the end of the chamber building.

The acid chambers are voluminous lead walled rooms built on wooden frames and supported above the ground, in this case about 12 feet to match the single story eave height. If we assume that there are 10 foot walk ways around the entire interior of the chamber building for inspection purposes and that this is a three chamber process then the size of an individual cell could be 15 feet wide by 170 feet long. The height of the chamber can be estimated as 15 feet; 20 foot height of walls less 5 feet for the support frames. This calculates to be about 38,000 cubic feet per chamber which is well within the established specifications for these types of facilities.

As the acid collects in the bottom of each chamber it flows by gravity to storage tanks under the chambers. It is then pumped from the tanks to the Glover tower for concentration. The usual means employed for pumping the acid is compressed air, I speculate that the engine room has a steam driven compressor to provide this air for the entire acid facility.

1897 Acid Towers

This detail shows the layout of the acid towers and there relationship to the burner building and the chambers. An enclosed pipe conducts flu gas from the burner building to the Glover tower, another covered pipe conducts gases into the chamber building. An additional covered pipe travels from the chamber building into the Gay-Lussac tower. The drawing indicates that the towers are 60 feet tall and having a foot print of 10 feet by 25 feet. Although not clearly identified I believe that the 8 foot square below the nitrous recovery tower is the chimney.

1897 Buildings Burner House

This is the 1897 burner building and pyrite storage shed. The shed is a one story open sided building with 20 foot eaves its dimensions being 48' long by 58' wide.

The burner house is also a one story structure with 12" thick walls (brick) on all sides, 88' long and 58' wide. There are two windows indicated on the side opposite the shed, this side extending 24" above the roof line. The side walls do not extend above the roof line and are also 20' above the ground.

Why Talk About Chemistry?

Before I go further in my discussion I want to clarify how I look at modeling an industry. I believe that you need to understand what an industry does in order to model it effectively. In the case of the sulfuric acid plant it is necessary to understand how the acid is synthesized, this allows you to understand how the manufacturing process effects the building in which the process occurs.

In this case it clearly allows you to understand the relationship between the components described on the 1897 Sanborn map. The acid towers are the Glover and the Gay-Lussac towers. The modern plant has no towers shown but since they are essential in the production of the acid they must be on the interior of the building. In fact the end of the building by the burners shows alternating high and low roof elevations, the high ones most likely cover the acid towers.

David

An Industry You Can Model 3

We will start the examination of the components of this facility by looking at the Sulfuric Acid Plant. This plant exists in both the 1897 and 1950 Sanborns. The 1897 plant is comprised of four components; a pyrite storage shed, a pyrite burner building with horizontal furnaces, two external acid towers and an acid chamber building. The 1950 era plant has a pyrite burner building with vertical furnaces, attached to a three cell chamber building with no acid towers indicated.

The primary raw materials in the production of sulfuric acid are iron pyrite (source of sulfur), water and sodium nitrate (catalyst). The pyrite is burned to release SO2 and provide heat for the reactions. The sodium nitrite is mixed with sulfuric acid releasing nitrous fumes which promotes the reaction of the sulfur dioxide, oxygen and the water in both the Glover tower and chambers.

The Glover tower is a reaction vessel in which nitrated sulfuric acid and chamber acid are introduced at the top of the tower. In there passed down the interior they encounter the hot combustion gases from the pyrite furnaces. The interaction of the nitrated sulfuric acid and the SO2 gas releases the nitrous fumes dissolved in the acid. As the chamber acid passes down the tower, any water it contains is evaporated. The steam created reacts with the SO2 and oxygen to create sulfuric acid. Concentrated acid is collected at the bottom of the tower and pumped into storage tanks.

After the gases pass out of the Glover tower they enter a series of large lead chambers where more water/steam is misted into the gas flow to produce additional acid. This acid is collected along the floor of the chambers, it is known as chamber acid, and is drawn off through floor drains. After passing through the third chamber the majority of the sulfur oxides have been converted to acid, the residual gas vapor now being nitrous gasses.

The nitrous gasses are recovered in the Gay-Lussac towers. Concentrated sulfuric acid has a great affinity for nitrous gas and is introduced into the top of the Gay-Lussac towers, the chamber gases entering from the bottom. As the acid mingles with the chamber gas stream it absorbs the nitrous gases. The acid recovered at the base of the tower is then pumped to the Glover tower. After passing through the tower the flu gases are vented to the atmosphere.

An Industry You Could Model 2

Examination of the map reveled several bone warehouses, gelatin plants, a bone black plant, a sulfuric acid as well as a muriatic acid manufacturing facility, ammonia storage tanks, a lime kiln and an ammonium carbonate plant, a phosphate rock storehouse, a fertilizer plant and packaging building. Also scattered about were several smaller warehouses and a water treatment facility.

Questions I asked myself were how did this diverse assembly of factory's create fertilizer and gelatin? What is bone black? Is this the gelatin you eat or something else? What was the history of the Michigan Carbon Works?

This link gives a history of the company and an overview of the products produced, http://www.ebonex.com/hist.htm

I will continue this discussion looking at each individual facility and try to explain the relationships between all of the various plants.

An Industry You Could Model

I have had long time interest in the Wabash railroad. In studying photos in the book Wabash In Color II, particularly photos taken around Delray tower, I noted that a spur ran south off the West Detroit Branch track crossing the joint trackage and paralleling the Michigan Central's mainline as it enters the city of Detroit. No mention of this spur was made in the book and I was curious as to where it went.

I had access to some Sanborn maps of the area and they suggested that this track was a connection to the MC and also served, via what appeared to be joint MC track, an industry identified as the Michigan Carbon Works. A quick look at the complex indicated that it was a fertilizer factory. This didn't sound particularly interesting until I took a closer look at the individual buildings which comprised the factory complex.

More later, David

Will It Work

Here are some photos of what I will call the prototype model. It is composed of 25 sections and is about six feet in length. The purpose was two fold, first to provide a really interesting model for a western mountain scene on the NAPM club layout, and second to proof out that the parts could actually be assembled into a model. It has worked out as planned and the next step is to build up the pilot model and document the construction steps.

The first photo shows the side with open ventilation doors.

The next photo shows the sides with closed ventilation doors.

The last photo shows the end view.

Four side variations will be possible in the kit. The model can be built without any side sheathing allowing a full view of the interior. It can be constructed with the ventilation doors closed or open. A final alternative is to modify the open doors to create a completely sheathed wall.

My plan for the kit is to provide enough parts to construct a 10 panel shed, a scale 200 feet. Each panel will consist of exterior sheathing closed door, back of open door, outside frame, support footings, center frame, support footings, rear retaining wall, roof supports, and roof section. Additional parts will be provided to allow construction of two 100 foot sheds if the modeler chooses.

So long for now, David

Snow Shed Model

Currently under development is a model of a typical western snow shed. The model is based upon a Great Northern prototype and is fabricated from resin castings. I have created the pattern work and am currently in the process of assembling a pilot model.