Finland
Port Neal, IOWA (USA)
Fertilisers
Railcar Loading & Fall Prevention
2013-2014
Background
The transfer of bulk fluids and solids from storage to transport is one of the few areas where a factory’s output is exposed to the atmosphere and human presence during its lifetime. This fluid/powder has been crafted using science and engineering. Sometimes, this takes minutes, but most likely, it is the summation of many hours of consumed energy, craft, and valuable ingredients.
The point at which the product is transferred from site storage to transport storage (drums or road, rail and marine tankers) creates several genuine risks for the integrity of the finished product, the operators handling it and the environment.
The Risks
In the fertiliser industry, the volumes of fresh and waste liquids classified as highly dangerous are abnormally high compared to many other sectors. In particular, acids, ammonia and other harmful chemicals that must be handled carefully are transferred hourly to provide feedstock.
In general, these are top-loaded into tankers and bottom-unloaded. The operators need to connect the transport container to the plant system quickly and without risk of injury through burns, inhalation or falls from height. The solution for safe handling can only arise from a multi-faceted approach to the problem, as detailed below:
- Falls from height
- Fluid handling
- Ergonomics
- Environmental
Each of these depends heavily on the design and ability of the other facets to allow the other to function effectively within its environs. In 2015, bulk fluid handling problems cannot be resolved by attempting to tackle a single aspect of the problem. Understanding that is key to making systems future-proof and capable of being operated by untrained or unfamiliar personnel while simultaneously providing a level of safety that meets corporate, local and national guidelines.
Look at these two recent projects Carbis Loadtec Group has worked on.
A Large Fertiliser Conglomerate, Finland
The first is carried out in Finland for a large fertiliser conglomerate.
The site receives railcars in two configurations for the import of ammonia. The position of the tanker connections is such that they can only use three of the four unloading spots due to the working range of the existing arms. Changing the arms in isolation would provide the increased range necessary to unload four tankers simultaneously.
However, preventing falls from heights meant that the only viable arrangement was to equip the bay with harnesses and wires. This being a 24/7 operation in a country where temperatures reach -40oC, the client considered that a safer method of accessing the tankers was needed.
Carbis Loadtec developed a unique safety cage system that would allow the client’s operators unrestricted access to each tanker with no risk of falls. These have unique flooring that allows the rail tank cars’ ladders to pass through without obstruction while the gap between the cage and tanker is minimised or eliminated. The operator can access the entire length of the rail car and position the liquid unloading and vapour return arm anywhere within the cage structure.
The connections are made using high-pressure couplings, and the design of the loading arms means that all that is required is simple and efficient guidance of the arms to working and parking positions. Every facet is covered and dealt with using a long-term viability approach. The system can deal with constant traffic for long periods and will remain ahead of any foreseeable legislation tightening on all facets.
CF Industries, USA
The second is also somewhat unique. CF Industries in Port Neal, Iowa, is building a state-of-the-art facility to manufacture urea, which is shipped in powder form to a processing plant on the Gulf Coast.
In this case, the rail cars are loaded continuously. The compartments are sealed using “coffin lid” style closures and filled from overhead hoppers using bellows systems. The solution for the quickest, safest and cleanest operator access and filling is to provide a safety cage that is almost 43 metres (140 feet) long.
The operators access the cage from standard gangways fixed to a permanent platform. They can travel the length of the cage using the built-in and fully enclosed walkway. When they need access to the compartment opening, they can step through the spring shut gate onto the tanker, open the compartment lid in cage one, operate the bellows in cage two, and close the lid in cage three.
The whole system elevates to allow clearance from the rail car. This is a unique and exciting development as the urea market in the USA begins to expand rapidly, and clients are looking for fool-proof, efficient and durable systems.
