Monograph 18

The influence of characterisation of water pulsation in water jigs on receiving selected mineral products process

Aleksander Lutyński, Mariusz Osoba

This research work describes the progress which has been made over some years in the development of pulsated jigs for the benefication of coal fines. It shows that a number of design improvements, including a new pulsator valve and the introduction of advanced drive systems, coupled with an electronic control system, have dramatically improved throughput and efficiency of jigs. The adoption of a computer-controlled system in the design of the jigs, together with the use of pneumatically-driven pulsatory disc valves, electrohydraulic units for the automatic control of the discharge of heavy product have provided several advantages: control of water pulsation within any selected cycle, automatic control over the discharging of the heavy product and automatic control over the loosening of the bed. This is the need for the correct selection of the characteristics of the pulsation cycle to match the specific type of coal which is cleaned. This work describes differences between results received in the jigging process for the normal sinusoidal jigging diagram in single-phase and for two and three-phase rotary or disc valves and describes also new potentials for the application of the jigging technology for gravel and sand preparation to separate mineral and organic impurities from the obtained aggregate. 

The results of the work were used in pulsated jig, designed to separate the sand-and-gravel feed into two products of grain sizes of 32-2(0) mm and to separate mineral and organic impurities from the obtained aggregate. An operation of the jig is based on a typical gravity separation of minerals and consists in a stratification of suitably prepared feed in the water pulsating environment, according to components size analysis and density. Proper operation of the jig is guaranteed by the electronic control system, which enables to control the water pulsation characteristic as well as the collection of washed gravel. Additional equipment of the jig is as follows: screw compressor and air blower. Rated output of the pulsated jig, which depends on sand content in the feed (max. 35%), for the operational surface of 4 m2 is 80-100 t/h. Innovative electronic control system (SES) enables to select the water pulsation characteristics, depending on technological parameters of the feed by use of electro-pneumatic drive (pulsatory drive), as well as controls the gravel collection by electric pulses provided by the float sensor.