At least five people are dead and more than 160 injured after an explosion at an anhydrous ammonia fertilizer plant in the small Texas town of West. Anhydrous ammonia is a highly toxic, volatile chemical that may have exacerbated the explosion and can blind, suffocate, burn, and kill humans. What is it? And why is it so dangerous?
What is it?
Anhydrous ammonia is a widely used, efficient form of nitrogen fertilizer. When used in agriculture, it's compressed into a clear, colorless liquid and stored at extremely low temperatures. In its natural form, in the open air, it's a gas, so agriculturists use special equipment to compress and handle it, storing it in tanks that can withstand 250 psi. But outside of that tank, it quickly reverts back to its gaseous state. Contact with it as a liquid can cause severe chemical burns and inhaling it can cause damage to the lungs. The "anhydrous" portion of it--"without water"--refers to the fact that the chemical reacts with water, meaning the effects are especially damaging when they combine with the human body's moisture, whether that's in the eyes, lungs, or other parts of the body. When that happens, the reaction forms a highly basic solution that's very corrosive.
Why is it used?
The same thing that makes it dangerous make it useful as a fertilizer. When injected into the soil as a liquid, anhydrous ammonia expands into a gas, where it's more easily absorbed by the soil. Adding nitrogen to soil is a potent way of making the soil more fertile.
What's the treatment?
There's no specific treatment, but it's recommended that anyone handling the chemical keep a nearby supply of clean water on hand. First aid procedure is to flush with clean water where the liquid meets the person's body, to dilute the effects of the burn. (A small amount of body moisture can cause the corrosive reaction, but a large amount of water will dilute it.) In its gaseous state, the ammonia might be even more dangerous. Inhaling it causes the chemical to react with moisture in the lungs, potentially damaging the lung lining, causing respiratory problems and even death. In that case, the University of Minnesota recommends people provide "cardiopulmonary resuscitation if the victim is not breathing, and summon emergency medical assistance."
Is it explosive?
Yes--under certain conditions, at least. It's not, on its own, very flammable, but if there's a leak of the chemical, it can ignite when it becomes about 16 to 25 percent of the air--a huge, usually detectable concentration--and reaches temperatures of at least 1,200 degrees Fahrenheit. Since it takes that much heat to ignite, the gas likely wasn't the source of the fire, although it could've ignited and exacerbated it if the fire was caused by something else. The tanks are also stored at high pressure, so could become explosive during a fire. And in the case of the West, Texas explosion, there was a lot of the stuff: as much as 54,000 pounds.
ten years ago, i was a lot different boy than the man i am now. i was arrested and served over a year in jail for possession of anhydrous ammonia. It is one of the ingredients needed to make meth. I have spent a LOT of time using and handling anhydrous nh3. It is some bad sh*t. I had a quart stored in a disposable fire extinguisher, (to keep it under pressure) It built more pressure than the vessel could hold, and exploded in my hand. I was burnt up and in the hospital for a week and then indicted off my hospital records. It is the coldest burn you could have.Anhydrous is some bad stuff. It will completely overwhelm you if there is ANY kind of leak. You couldn't pay me now to go around that stuff. I cant imagine what the emergency personnel are having to go thru breathing around that stuff while putting out the fires.
Please note that when you mix it with water it turns into ammonium hydroxide, which is a common floor cleaner typically called ammonia.
I agree it is bad stuff. I hauled tanker loads of it years ago. You need to wear a respiratory mask to load and unload it. Scary is some of the people handling it.
I went into a BC hydro site north of Vancouver years ago. I was restricted to night movement as I had to pass through a residential area to access the unload location. Upon arrival I was assisted by a power engineer for the unloading.
At first the product starting flowing off the tanker because of pressure in the trailer vessel. When the pressure dropped after about 10 minutes, his automated computer program for unloading shut down. He tried restarting it several times and it would shut down right away. He wandered around the plant and said he did not know what was wrong. I asked if he would mind if I had a look as I also hauled propane and the system was similar as a compressor pushed the product off. He said OK so I had a quick look at the pipe pumping.
I found intake valves were shut off to the compressor so it was starving for air in the enclosed pipe system. It was heating up and sending an error code to the computer, there fore it would shut down due to built in safe guards.
I opened the valves and he restarted his computer program and the load finished coming off fine. Later I thought that is pretty pathetic that the truck driver had to show the guy with a power engineering ticket how to find the problem. He was probably making 3 times the money.
Pretty scary to think about some of the people they have in charge of these very dangerous products.
Cosmic fabulous icon and awesome comment, thanks for the info!
so an explosion at a place where there are safety standards put in place to prevent it, with a chemical that doesn't explode unless mixed with the air correctly, at a location where the casualties would be high but not too high, and we're still calling it an industrial accident. how come posci didn't say anything about the other chemical explosion that happened at the same time in oaklahoma?
to mars or bust!
Stick to the facts people:
1. West Fertilizer was NOT an anhydrous ammonia plant as stated in the article. I work in an ammonia plant and that is not what a plant looks like. West Fert was a storage a distribution facility. Ammonia was stored there along with many chemicals, etc., which ALL may have been contributing factors.
2. Despite the implied message that an ammonia release contributed to the explosion and injuries / fatalities, there have no reports that support that speculation - no reports of burns, suffocation or nasty smells that accompany ammonia releases.
3. It is important to note that many dangerous chemicals are closer than we think all the time. The key to avoiding disasters like this one is being prepared for the worst case scenario, which was obviously not the case here.
It's a terrible situation which could easily have been prevented.
I think the whole "anhydrous kaboom" is exceptionally over-rated. Some news agencies are now stating it was the Nitrate now.
Much simpler if the huge pile of abandoned pallets visible on satellite view up by the two Ammonium Nitrate storage silos overheated the agricultural grade solid fertilizer inside. - Pretty simple in the end, little kaboom causes big kaboom. This being supported by debris arriving BEFORE shockwave in the cell-phone video from the pickup truck on the grassy knoll.
One would think that Texas had learned not to store flammable materials next to solid fertilizer, what with Texas City and all...
This facility clearly had a second Anhydrous storage tank that was dismantled some time in the past.
The anhydrous ammonia (NH3) in question was used to MAKE fertilizer. That and other toxic chemicals like nitric acid, for example. What detonated, to such devastating effect, likely occurred in the stockpile area of the plant, where the finished product, ammonium nitrate prills, was being stored prior to sale in bulk or prior to being bagged. The most important question is where and what caused the fire that eventually reached the the large stockpiles of fertilizer.
The first-responders were quite aware that most profound danger to the nearby public was from explosion, not an ammonia leak (NH3 is lighter than air, and dissipates rapidly). They should have concentrated their efforts in evacuation activities, while maintaining a cordon beyond the worst-case-scenario blast vulnerability zone. Why residential or commercial building were allowed to be built within this blast zone is another question that should be asked.
Texas, of course, is infamous for its disdain for worker and public safety rules. The EPA and OSHA are going to fine the company out of existence after the Chemical Safety Board concludes its investigation. Whatever's left will go to the lawyers of the victims. But, I'll bet dollars-to-donuts that a Texas state legislator is already drafting a bill that would retroactively limit the liability the owner is responsible for in this disaster. That's how it is done in Texas.
@Duncan Idaho: My first question when I heard about the explosion was not how, or why it happened, but what kind of genius approved the zoning in West, Texas in the first place?
Even if chemical industrial facilities don't blow up on a daily basis, there are still some inherent risks with these places. Approving the construction of residential buildings, homes for the elderly and schools /right next door/ to such a site is not only irresponsible, it is downright stupid.
A letter in response to her article:
Your article, Liquid Ammonia at Texas Plant Had Small Window to Explode, answers questions I had when I wrote my comment in response to others. I thought you might find it interesting, especially, the frame of the video showing the explosion originating from one of the tanks of anhydrous ammonia. This is what I wrote.
[Support the VFD: In response to other blogs filled with blamers.
The cause of the explosion: A suggestion based on physics and videos, submitted by mystirc.
A frame-by-frame analysis of videos, especially, that by the father with his daughter, parked on the west side of the factory; shows that had the 35 to 40mph wind been blowing from any other direction than South, the explosion might not have occurred. The fire and smoke were blowing nearly horizontally toward the tanks. The tanks of anhydrous ammonia were directly north of the building fire and the smoke trail was blown directly into the first tall tank. When the first responders arrived, they should have broken protocol, attacked the fire from the north, the smoky side, and sprayed water into the smoke to reduce the temperature, as well as the base of the fire, which is the proper way to attack a fire. In addition, they should have called for reinforcements to attack the fire from the other side because they had to keep attacking the heat in the smoke hitting the first tank. That smoke appears to have heated the tank of anhydrous ammonia, increasing pressure well beyond the required 250psi design, to the point of rupture, releasing massive amounts of NHз reaching the perfect mixture of 16-25% for the flash point of 1200 degrees F and then the tank exploded. Only one frame shows that the explosion occurred from the end of the smoke trail, coming from the tank outside the left side of the video, not from the building, which was already burning, on the right side of the video. In no way would I accuse firefighters of anything. They did the best they could considering they could not see the situation as I did from hundreds of yards away through the video. The overall responsibility is to plan for such a possible situation by the local authorities, the plant owners, the plant safety division, the EPA (totally underfunded), and probably some others. In no way should any of the blame be put on the first responders, especially, since I do not agree that their spraying of water had anything to do with the explosion. The main question now would be how and why did the fire start in that building and how did it get so out of control in a fertilizer plant?. Moreover, please, ask yourselves, did any one of the first responders wake up that morning thinking that today is the day I’m going to screw up and hurt others? I think not! I’m sure that all of them were guys and gals with whom I’d love to have a beer and throw darts or play pool, even if we disagreed on politics, religion, social issues, gun regulation, immigration, or whatever, and just brag about our kids. I loved them all before they were born, and Lord, may I enjoy meeting them all.]
This disaster, if this is the cause, is reminiscent of the first shuttle, the Challenger, explosion when the main fuel tank received heat directly from an assembly junction on one of the side rockets. Other articles imply that the plant was built first, but the town was built next to the plant long before the large storage tanks were installed. After the tanks were there, the permit was finally approved in 2006, and the governing agencies accepted the verbal and written statements of the company that there was no danger of explosion. Apparently, no one thought to consider the worst-case scenario. I’m sure the authorities investigating will examine the videos frame by frame with much better equipment than mine. It is so sad that the fire fighters and other first responders did not realize what was happening; like the Challenger astronauts, they didn’t have a chance.
Maybe the EPA should require large hazard placards all around the tanks about how dangerous any heat will increase pressure to explosive range. I have no idea what signs were on the tanks, but isn’t what needs to be done is something that would have triggered instinctively in the minds of plant personnel and first responders that heat from the fire couldn’t touch the tanks.
Anna Edney’s article is at bloomberg.com