Starter Strip Nickel Removal Process Design

Abstract

A new system design for removing leftover nickel from the refining process was required by Vale at their Thompson, MB facility. After the refining process, some nickel remains on plastic starter strips and must be removed so that the strips may be reused and the nickel is recovered. The current removal system involves an employee manually removing the nickel by hitting the starter strips against a hard surface, which is labour intensive, unsafe and time consuming. The client required a design that required less manual labour by the employee, was safer, and improved through-put of the cleaned starter strips. The final design selection was made by first collecting a broad range of initial concepts and ideas, which were later refined into preliminary designs. These designs were then screened for feasibility through scoring schemes which evaluated their expected performance against the requirements and constraints of the design problem. The five highest scoring designs were further researched, and the final tilted tumbler design was selected. The tilted tumbler design consists of a rotary tumbler mechanism made up of two five-foot long concentric drums, with a major diameter of five feet open at both ends. The diameter of the inner drum will contain the starter strips and nickel and is intended to clean approximately 500 strips per batch, with each batch intended to tumble for 30 minutes. Based on an eight-hour workday, this will allow approximately 8000 strips to be cleaned per day which is a 60% increase to the through-put of the current system, approximately 5000. At the end of the 30-minute tumble cycle, the strips will remain in the inner barrel, and the removed nickel will have fallen into the outer barrel through holes in the inner barrel. The constraints of the working environment ban the use of galvanized steel or aluminum; therefore the tumbler system will be made from 316 stainless steel. The door on the unload end of the tumbler will have two separate access hatches that can be opened to allow separate unloading of the nickel and starter strips. The strips for cleaning enter the inlet end […]