Look around you. Chances are that much of what you see – from the paint on the wall to the adhesive under your carpet – began inside a liquid bulk tank. In our previous article, we introduced you to these tanks along with some of the other equipment involved in bulk liquid transportation.
We’ll continue with liquid bulk basics in this article by examining the processes employed by bulk liquid tanker carriers to get liquid products into and out of these tanks and into the supply chain.
Loading and unloading bulk liquid tanks
As important as having the right liquid tank and equipment are the processes that put this equipment into action. And, as with many things, procedural success starts with simple communication.
For starters, you will want to put your service partner (i.e., your bulk liquid tanker carrier or freight broker) in touch with at least one person at the pickup site – and one at the delivery site – who understands all the necessary requirements. Your partner will reach out to that point of contact to confirm key details about procedures and equipment.
If your driver is responsible for loading and/or unloading, make sure you always have someone supervising that work. The driver might be in charge, but if something goes wrong, the headache is yours.
Prior to loading, you must first make sure the driver knows what the product will be loaded out of (e.g., a tank, a series of drums, or other containers) and has the right equipment to do the job. Next, the trailer must be inspected to ensure that it is clean, dry and odor-free.
When it is time for unloading, the receiver should first take a sample to confirm that the truck has brought the right product and that the product is in good condition. As the driver attaches the hoses, the receiver should double check to make sure the product will be flowing into the right tank or other container.
There are two primary methods for unloading a trailer, compressor and pump, and there is an important difference between the two. When unloading with a compressor, the dome must be closed. But, when you’re unloading with a pump, the dome must be open, otherwise the vacuum set up by the pump could collapse the trailer walls, ruining a piece of equipment worth over $100,000.
As for the trailers, some unload at the center; others from the rear. This difference can be important. If your truck is parked on a surface that pitches upward and you’re unloading from the rear, some of the liquid will stay stuck in the front end of the trailer. That leftover bit, called the “heel,” can prove expensive: if you can’t get it out, you’ll need to dispose of it elsewhere. To avoid waste, make sure the mechanism for unloading fits the environment where you’ll be using it.
Liquid bulk tank washing
One of the biggest differences between liquid bulk and other kinds of freight is the need to wash the trailer. It’s a vital – though inconvenient – part of bulk liquid shipping that prevents cross contact of products and contamination. When a driver arrives to pick up a load, you should not only inspect the tank, but also ask the driver for a washout slip from the wash station. This document tells you exactly how the equipment was washed, letting you know if it was done correctly.
This tank washing requirement adds extra time to every shipment. It also adds cost, partly because every shipment includes deadhead miles, and partly because the shipper pays for the wash. After dropping a load, the driver might have to travel an hour or more — maybe even to another state — to reach a suitable tank wash station.
Not every washing facility is designed to clean every liquid bulk tank. Some handle chemicals only, while others are designed only for food-grade loads. The wash station may use detergent, steam or a caustic wash to clean the tank, depending on the last product hauled. Along with the trailer, the station also washes pumps and hoses.
The cost of washing the trailer may appear on your freight bill as a separate charge. For some products, bulk liquid tanker carriers will apply a standard washing charge. For others, the carrier will pass along the actual dollar amount that the wash station charges. To avoid surprises, ask about this charge when you book the load.
Finally, there is one exception to the washout requirement: a tank wash may not be required when a carrier unloads a liquid product and then plans to load the exact same commodity.
To read our full eBook about the basics of bulk liquid transport, download Liquid Bulk Freight 101. And, when you’re ready to get your own liquid bulk products on the move, contact Bulk Connection to speak with an expert that’s been transporting bulk liquids for over 30 years.