Overland Conveyor System India's first Elevated, Triangulated Gallery Overland Conveyor System
In 2010 the Adani Group broke ground on a new solid cargo handing port with the installation of a unique conveyor system that moves up to 6000 t/h to a rail loading silo approx. 4.75 kilometres from the port. These conveyors are supported by lightweight triangular galleries that do not include walkways and are maintained with a motorised trolley.
In March 2013 the Adani Group commissioned two high speed (7.5 m/s), elevated, horizontally curved conveyors (1100 m radius), that transport 6000 t/h of coal from the Dahej Port to a wagon loading silo. These conveyors are supported by unusual lightweight triangular galleries spanning 36 m each and weighing only 209 kg/m. The triangular galleries do not include walkways and are maintained with a motorized trolley. This article discusses the design and construction of this unusual conveyor system.
Located in the Gulf of Khambhat in the Bharuch district of Gujarat on the west coast of India, the Adani Group's new solid cargo handling port at the city of Dahej includes two fully mechanised deep draft berths for excavating coal from cape class vessels at a rate of 4600 t/h. Excavated coal is transported by conveyor to two stockpiles holding 125000 t apiece. Two 2500 t/h reclaimers discharge coal from these stockpiles onto Yard Conveyor J10C1. The discharge chute at the head end of J10C1 includes a diverter gate that allows operators to either direct coal to a truck loading conveyor, or direct coal to the “Silo Conveyor” System that moves up to 6000 t/h to a rail loading silo approx. 4.75 km from the port. From the silo, coal is transported by a private Adani rail network to an Indian Railways station.
Conveyor Dynamics, Inc. (CDI) was initially awarded a contract by PMC Projects (a subsidiary of the Adani Group) to produce a basic engineering design of the elevated Silo Conveyors, and a basic engineering design for the Adani Power Conveyor system PMC intends to build in the future to transport coal from the terminus of the second silo conveyor to a new power plant they will build 10.85 km away.
After CDI completed the basic engineering, PMC realized that acquiring the land in the conveyor corridor posed a significant challenge. To avoid large change orders, the Adani group decided to handle all procurement, construction, and project management in-house. CDI was awarded a new contract to supply PMC with detail engineering design drawings of the silo conveyors and their supporting structures as well as a control philosophy. CDI also provided consulting services during fabrication, and support services during commissioning of the silo conveyors. The transfer house detail drawings were supplied by Elecon Engineering Co. Ltd (Elecon). All electrical and instrumentation work including PLC logic development and programming was completed by Larsen and Toubro (L&T). Project management was handled directly by PMC.