AWARD OF EXCELLENCE: Quadrant Shiploader for Koch Carbon Pittsburg, California

Category: Industrial

LASSING DIBBEN CONSULTING ENGINEERS & UMA CONSTRUCTORS

UMA Constructors obtained a contract from Koch Carbon Inc. to engineer, build and commission a complete new marine terminal on a greenfield site beside the Sacramento River in Pittsburg, California, about one hour east of San Francisco. The terminal includes a shiploader and landside belt conveyor feed system.

At the new facility Koch Carbon handles and markets the petroleum coke from several petrochemical refineries in the Bay Area. The coke is brought by truck to the terminal, then sold and shipped internationally.

The company needed a method to load Panamax sized vessels more quickly. Loading these large ships can be time consuming due to the fact that traditional shiploaders require the vessel to be repositioned regularly as the various holds are filled. UMA Constructors contracted Lassing Dibben Consulting Engineers to prepare the design for a shiploader using a belt conveyor that would meet Koch Carbon’s technical requirements, while also satisfying the rigorous environmental requirements of the Bay Area Air Quality Management District, and the Uniform Building Code structural regulations for the area. Lassing Dibben also provided assistance with field engineering and commissioning. A history of collaboration between the two Canadian firms fostered a dynamic environment in which to approach the project, which was multi-disciplinary and involved Canadian environmental, structural, civil, marine, mechanical, electrical and construction engineers.

Quadrant design

The shiploader is called a “quadrant shiploader” in the bulk material handling industry, as it is able to rotate on a rail that is the “quadrant” of a circle. The shiploader can rotate about its pivot point (slewing) at a radius of 64 metres from pivot to rail over a range of 120 degrees. The shiploader can extend its length (shuttling) from a base length of 84 metres to a fully extended length of 125 metres. It is also capable of lowering or raising its discharge point by pivoting its extended boom (luffing) by an angle of 16 degrees above horizontal and 15 degrees below horizontal.

All the above movements can operate at variable speeds and permit the shiploader to completely cover all the holds of a Panamax vessel (almost the length of two football fields) without the vessel having to move. The shiploader can also manoeuvre in all three dimensions to avoid any obstructions on the deck of the vessel.

Due to California’s strict environmental controls, the shiploader had to be designed and constructed so as to have no impact on the air, land or water. UMA and Lassing Dibben designed the system to be totally enclosed so that the product is not exposed to the environment. The enclosures are conveyor belt covers, specially designed seal belts and stainless steel catchment trays the entire length of the shiploader. At the point of discharge an automatic retractable spout was installed to maintain the discharge point directly on top of the material in the ship’s hold so that no dust is generated. As a further back-up, a high efficiency dust collector was installed directly above the discharge point. The entire shiploader has an internal wash-down system and water collection for the wash-down water.

The shiploader was constructed 18 kilometres from the Green Valley Branch of the San Andreas Fault System and only 70 kilometres from the main San Andreas fault line itself. It was designed to the requirements of seismic zone 4 of the Uniform Building Code, which is the most severe earthquake zone in North America.

Building and operating

The constructability aspects of the shiploader design also called for innovative solutions. The main bridge girder of the 600 tonne shiploader was constructed and assembled off site, and transported to the site by river barge. Engineered lifts were then used to raise the bridge from the barge onto its pivot point and the slewing rail.

Because there is limited visibility into the ship’s hold, an operator’s cab was not included. Instead the operator supervises the loading directly from the ship’s deck using a remote radio control unit he supports on the shoulder.

The turnkey project was on a fast track schedule, with accelerated design, equipment supply and construction. The shiploader was turned over to the owners in April 1998. It has met or surpassed all the environmental requirements and is now the standard against which new shiploading facilities will be measured for operating in heavily populated areas of the United States. CCE

Project name: Quadrant Shiploader for Koch Carbon

Owner: Koch Carbon

Award-winning firm: Lassing Dibben Consulting Engineers, Trenton, Ont. and UMA Constructors, Mississauga, Ont.

Project team: (Lassing Dibben) Harold A. Dibben, P.Eng., Thomas A. Coates, P.Eng., Julie R. Hietala, Rod MacKenzie; (UMA) Malcolm MacKay, P.Eng., Mike Whitby

AWARD OF EXCELLENCE