Figure 1 – ESP design

1 grit pulp supply pipe; 2 flow swirling chamber; 3 gear motor; 4 water drain pipe; 5 organic compounds drain pipe; 6 technical water supply pipe; 7 mixer; 8 grit discharge conveyor; 9 grit discharge zone; 10 water drainage after dehydration

A mixture of water, grit and organic substances is fed into the device through the supply pipe (1) and flows through the flow swirling chamber (2) into the cartridge. The swirled flow changes from the vertical to horizontal direction, and a definite flow field is formed in the reservoir, creating thereby optimum conditions for the separation of the mineral inclusions from the mixture. Since the deposition depends on both particle size and density, not only mineral but also organic inclusions are precipitated.

Separation of mineral particles from organic ones occurs in the lower part of the device free of intensive movement. For this purpose, a certain amount of water (technical) is supplied to the device through the supply pipe (6), thereby creating a fluidized bed where the particles behave as if in a boiling liquid, constantly colliding with each other. This fluidized bed makes it possible to separate organic substances from grains of grit, regardless of the particle size. This separation by density of the grit-organic mixture components is maintained by a mixer (7) with a low rotational speed. The grit cleaned from organic inclusions is automatically discharged outward by a screw conveyor (8). It is simultaneously dehydrated statically, and then discharged into a container. The organic matter remaining in the device is discharged through a special drain (5) – also automatically, but in intermittent mode and depending on the process parameters. The separated water is collected in the annular chute through the spillway and discharged through the drain pipe (4).

The ESP grit separation and washing device can operate both in manual and automatic modes and is supplied complete with a control system that ensures the continuous operation of all units and devices. The control system consists of a control cabinet (installed in the control room), equipped with a touch screen and a local control panel (installed in close proximity to the equipment).

In the automatic control mode, the operation of all actuators takes place according to a special program without operator’s intervention.

The manual control mode is intended for routine maintenance of the separator. At the same time, independently of each other, a solenoid valve (technical water supply), a mixer, an organic waste flow damper and a conveyor can be activated using the local control panel.