While tank containers are known for transporting liquid products, ISO tank containers are built based on ISO standards (International Organization for Standardization) and are designed to carry liquids in bulk, both hazardous and non-hazardous.

These containers are made of stainless steel and are surrounded by various types of protective layers. Based on the cargo type, different skins can be used. The container has a manhole on the top along with at least one valve and another valve on the bottom. They are shaped like a cylinder. Since ISO tanks are built based on ISO standards, the frame which the tank sits in measures about 6 meters long, 2.4 meters wide and between 2.4 – 2.5 meters high and vary in size and type and can carry between 21,000 and 40,000 liters of liquid.

Below are the types of liquids can be carried in ISO tank containers.

1. Molasses
2. Milk and other dairy products
3. Alcoholic and Non-Alcoholic Beverages
4. Liquefied sugars
5. Hydrogen Peroxide
6. Sulphur Acid / Nitric Acid
7. Chemicals / Solvents
8. Liquid Food Products
9. Heating oil / Vegetable oils
10. Gasoline / Diesel / Liquefied petroleum gas
11. Liquid Resins

Below are some of the benefits of ISO tank containers.

1. ISO tank containers are a reliable, cost-effective (depending on the product being shipped) and definitely safe way of transporting bulk liquids.

2. ISO tanks are designed to meet specific criteria according to the substance they will be carrying.

3. Because of the above, ISO tanks are very reliable and can withstand extreme pressure and damage.

4. ISO tanks are highly unlikely to leak and do not require additional packaging materials for cargo.

5. ISO tanks maintain a specific temperature for temperature-sensitive cargo and can be transported by land or ocean.

Flexitanks vs. ISO Tank Containers for Bulk Liquid Transportation

Since ISO tank containers are often compared with Flexitanks, I would say this comparison can be applied depending on the product type along with the Origin/Destination of the shipment. Flexitanks and tank containers are both used to transport bulk liquids. Depending on what you are shipping and the Origin/Destination, one method can be better than the other.

Bulk liquid transportation is an important segment of the freight transportation industry. Depending on the type of product being shipped, the origin of the product and the cargo’s destination, the most reliable and economical method of bulk liquid transportation may not be obvious.

While ISO tank containers and flexitanks are both used to efficiently transport bulk liquids, there are some distinct differences between these two options. Flexitanks are cost-effective when product is non-hazardous depending on the Origin/Destination. Due to high cost of repositioning tank containers back to origin of the cargo if there is no two-way business in Origin/Destination, these tanks need to be repositioned back to their origin or somewhere where tank container suppliers need. Therefore, this increases the cost of ocean freight. In this scenario, flexitanks can play a crucial role to maintain freight advantage versus tank containers.