Page 22 - HUB-4 Magazine Issue 84

Recycling News
Beating a battering from batteries in Mexico
One example that Martin Engineering was involved with was in Mexico, at Enertec at a plant dedicated to the recycling of vehicle batteries. The machinery grinds down and separates the plastics from the lead in spent batteries and the materials are reprocessed and used to manufacture new batteries.
However, their main conveyor belt suffered from continual impact damage and misalignment as a result of heavy batteries dropping onto it. Smaller batteries (such as motorcycle batteries) tended to rebound out of the loading chute because the conveyor belt lacked an effective support system.
Enertec's conveyor belt suffered from impact damage and misalignment.
Copyright © 2023 Martin Engineering
Some of the batteries ran down the back of the chute, which caused damage to the conveyor belt and also to the tail pulley. And others fell down the sides, getting stuck between the chute and the conveyor and accumulating over time. In addition to this problem, the lack of proper support meant that significant vibration was being transmitted to the nearby weighbridge.
All these issues were causing repeated drops in productivity and an increase in unplanned maintenance to allow corrective actions to be taken – this was mainly carried out during unscheduled shutdowns when it was necessary to manually clear the chute and surrounds, as well as replace and repair damaged conveyor components. Besides the loss of production time this was also expensive and labor intensive, not to mention the additional risks of clearing the blockages by hand.
Following examination from technicians at Martin Engineering, the solution came with the installation of an Impact Cradle positioned under the belt conveyor loading zone beneath the chute. The Impact Cradle absorbs the force of falling objects and materials to prevent damage to the belt
Martin’s Impact Cradle absorbs the force of falling materials and objects to prevent damage to the belt and structure and eliminates any belt sag. Copyright © 2023 Martin Engineering
and surrounding structure. It eliminates any belt sag and is designed to minimise any bounce-back from the initial impact with the belt.
Like many of Martin’s installations the cradle was custom- manufactured to meet Enertec specific requirements – in this case that meant it had to be made from stainless steel to resist attack from the corrosive acids in the electrolyte solution of the batteries they recycle. Following installation, the problems of misalignment and impact damage were corrected and Enertec recorded fewer production problems and lower maintenance costs.
Stemming the spillage from steel slag in Germany
Another example comes from the steel industry in Germany, where residues from the blast-furnace are transformed into a cement substitute known as GGBS (ground granulated blast- furnace slag). This happens at steel plants the world over.
In this case the producer was experiencing extreme carryback on a main material transport belt, which was causing excessive build-up beneath the conveyor and significant damage to the superstructure and conveyor system. An existing belt cleaner made from a horizontal strip of metal plate tilted slightly to face the discharge chute did not adequately remove dust and fines from the cracks and divots in the belt.
Carryback on the return side of the belt caused fugitive dust to travel away from the operation area and crested poor air quality throughout the plant. Spillage along the belt path also built up around the mainframe and increased operational costs for cleaning. The arrangement was impacting productivity and increasing maintenance costs. It also had the additional disadvantage of damaging the belt and catching on mechanical splices, causing costly premature belt replacement and running the risk of a catastrophic breakdown.
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www.hub-4.com Jan/Feb - Issue 84