Working with U.S. Borax › Shipping and Handling

Shipping and Handling

Recommendations for optimal processing

Bags or Bulk

Most Borax customers choose delivery of product in 50-lb or 25-kg bags. Others prefer bulk delivery, particularly of our Neobor^®, Optibor^®, Dehybor^®, and borax decahydrate products. Whichever method you prefer, our refinement processes help to improve your shipping and handling experience by reducing the potential for dust and caking. For an optimal experience, we suggest following a few best practices.

Handling Bagged Borates

Handle bagged borate products with care. Avoid puncturing bags while using sharp instruments. A hole in a bag not only results in spillage but might expose the product to moist air, which can cause caking. Punctured bags also increase the potential for product contamination. For more information about the packaging and storage of bagged products, see Packaging and Storage or download the Borate Handling and Storage technical bulletin.

Borate best practices

Handling Borates in Bulk

With increasing demand and changes in industrial practice, many users of sodium borates and boric acid—particularly Neobor borax pentahydrate, Optibor boric acid, Dehybor anhydrous borax, and borax decahydrate—find it more economical to use bulk transfer.

Neobor is the most stable of the three sodium borates and is ideally suited to bulk transfer. It shows little tendency to cake, except after prolonged storage or severe wetting by rain or other substantial water ingress.
Optibor is also ideally suited to bulk transfer. Like Neobor, Optibor shows little tendency to cake, except after prolonged storage or severe wetting.
Borax decahydrate shows the greatest tendency (among the sodium borates) to cake. However, it can be successfully shipped and handled in bulk if proper precautions are taken.
Dehybor generally handles well in terms of its flow characteristics, but attention must be given to the abrasive nature of the particles. When handling large quantities or for long-term, continuous operation of the unloading plant, we strongly suggest using mechanical transfer equipment rather than pneumatic systems.

The relevant physical properties of these products for handling and storage are summarized in the Borate Handling and Storage technical bulletin.

Handling borates in bulk

Bulk Delivery Systems: Railcars, Trucks, and Containers

Trucks and containers can typically ship a bulk load of 18 to 28 tons; railcars, 100 to 110 tons. Before converting to bulk shipment, we suggest that customers work with their supplier to determine the most appropriate transport system.

Railcars generally have a bottom gate for discharge between the tracks. However, some cars are equipped for pneumatic discharge—either with their own pneumatic systems or using the customer’s equipment. The average hopper car is approximately 4,450 ft³ (126 m³) and holds 100 tons (90,700 kg). Cars are available upon request, with dual systems for unloading via either gravity or pneumatic methods. All cars are equipped with center dump gates.
Trucks are generally equipped with their own pneumatic discharge systems, operating at pressures of about 29.4 psi (2 atmospheres). These trucks can deliver into silos up to a height of 100 ft (30 m). Avoid long horizontal runs of piping.
Containers (with or without liners) are emptied by gravity or by suction using the customer’s equipment.

You can find schematics and specifications for railcars in the Borate Handling and Storage technical bulletin.

Shipping and handling

Unloading Product

Gravity unloading is the typical choice, especially with products that tend to cake and form lumps under certain humidity and temperature conditions (e.g., borax decahydrate). Gravity unloading is accomplished by discharging product directly from a rail hopper car to a pit located between the rail tracks. Customers should use an air-operated impact wrench to open and close the slide gate, which can bind with the build-up of product in the slide tracks. Product can then be discharged at a controlled rate from the track hopper, through an adjustable slide gate, to a mechanical conveying system, and then to a storage silo.

Pneumatic unloading is done by vacuum or combination vacuum-pressure techniques. Neobor and Optibor are nonabrasive, so this procedure can be used to easily convey these products directly from the car to the silo. A flexible hose with quick coupler is usually attached to a side port on the car; the other end is attached to permanent piping that runs parallel to the silo. This unloading method prevents the product from being exposed to the elements; the closed system eliminates the potential for contamination from outside sources.

For more information about unloading systems, see the Borate Handling and Storage technical bulletin.

Unloading product

Borax decahydrate contains a higher percentage of water than either Neobor or Optibor, making it more prone to caking. Therefore, although pneumatic unloading is possible, mechanical unloading is strongly recommended. If pneumatic unloading is used, gravity discharge the product through a double-finger crusher and into a holding bin before pneumatically conveying it to the silo.

Transferring Product

A mechanical conveying system can consist of belt conveyors, screw conveyors, and centrifugal bucket elevators. Electric or air vibrators mounted near the discharge opening of the track hopper can facilitate discharge, if necessary. Mechanical systems should incorporate sealed transfer chutes or dust extraction.

Pneumatic conveying systems have the advantage of being dust-free. Neobor, Optibor, and borax decahydrate can be air conveyed by pneumatic pipe systems or air slides. Dehybor, because of its abrasive nature, requires the use of ceramic or hard-faced liners at specific points where abrasive wear is expected: elbows, transition pieces, and impingement surfaces in cyclones, diverters, and receivers.

If considering an air slide to convey Borax Decahydrate, use the same precautions noted for pneumatic unloading (gravity discharge through a double-finger crusher and into a holding bin before conveyance). Use only dry, cooled air and be sure to maintain air conveying temperatures below 95°F (35°C). Air conveyance is not recommended for locations that are frequently humid with high ambient air temperatures.

The Borate Handling and Storage technical bulletin provides additional details and important recommendations for product transfer.

Transferring product

Ideally, unloading and transfer equipment should be sheltered from direct rainfall. Caking (as opposed to mild consolidation) usually occurs only when the material becomes wet as a result of a massive ingress of water.