Prediction of automated sorter performance utilising a Monte Carlo simulation of feed characteristics

Abstract

a b s t r a c tTo evaluate the performance of an automated sorter typically requires testing of the material to be separated on a full-scale device. In many cases limitations on the quantity of material available for testing, and the costs of the test programme, may limit the range of operating conditions examined. In this paper we propose a method for prediction of automated sorter performance, based on material and machine characteristics, which can be used to evaluate how changes to these characteristics affect performance.The distribution of particles at the point of identification is a key parameter in determining sorter efficiency. A Monte Carlo simulation was used to predict the position of particles on a feed conveyor used to deliver particles to the identification zone. The results produced show that this technique can be used to simulate the particle distribution achieved by an operating automated sorter (TiTech Combisense).Sorter efficiency depends on firstly accurate identification of the target product (typically deflected) and secondly the precision of selective deflection, using compressed air jets or mechanical actuators. A reduction of deflection efficiency is generally caused by the co-deflection of ''non-target'' particles resulting from their close proximity to particles being deflected. In order to fine tune the sorter model data from automated sorting experiments were analysed to provide information on deflection efficiency over a wide range of operating conditions. The sorter model developed for the À10 + 6 mm size fraction was shown to provide a realistic prediction for coarser (À15 + 10 mm) particles.The sorter model was used to demonstrate that sorter performance could be significantly improved by improved particle feed distribution. When a high separation efficiency is required for a sorting application a 3 stage process was predicted to have a higher separation efficiency than a single stage process using the same number of sorters.

Identification of a mixture of grain particle velocity through the holes of the vibrating sieves grain separators

“…-оптимизацией кинематических режимов [5]; -аналогии с гидродинамическими моделями [6][7][8][9]; -механики сплошных сред [10]; -моделирование вероятности просеивания частиц различными методами, в т. ч. методом Монте-Карло [11,12];…”

Experimental Evaluation of a Novel Sensor-Based Sorting Approach Featuring Predictive Real-Time Multiobject Tracking

“…In [41], the authors propose a definition of separation efficiency and utilize it to quantify sorting performance as a function of the proximity of objects in the material feed. They further investigate different feed characteristics by means of a Monte Carlo simulation and quantify results based on their prior introduced definition of sorting efficiency in [42]. Following the concept of receiveroperating characteristic (ROC) curves, the idea of a sorting optimization curve (SOC) is presented in [43].…”

“…With respect to the amount of material to be deflected, we consider a ratio of 5%. The impact of the mass flow and ratio to be deflected on sorting performance has already occasionally been investigated in the literature, e.g., in [41], [42].…”

“…There exist different approaches how the pattern can be calculated [49]. As also done in [42], we use the common approach of using the bounding box of an object to be deflected to calculate the deflection pattern. However, we consider two configurations.…”

Intensification of the process of dosing bulk concentrated feeds by sieve hopper

“…Adequate simulation of the motion of bulk materials during their separation into fractions, as well as their passage through the holes of vibratory sieves, was conducted using the analogy with hydro-medium [17,22] and continuum mechanics [23]. To study the parameters of motion of granular materials, we used the theories of probability of particles passing through the openings [24], as well as the methods of discrete elements [25].…”