FR3048621A1 - CONCENTRIC TRAP FOR SOLID PARTICLES IN LIQUIDS - Google Patents

Abstract

The invention makes it possible to filter the solid particles in the liquids by limiting the pressure drops. The device consists of a conical shaped mesh basket on its upper part (1) (FIG. 3) and of cylindrical shape on its lower part (2) (FIG. 3). The solid particles are directed by the conical shape toward the center of the filter and are trapped concentrically in the central cylindrical shape while the liquids flow freely without loss of load. This filter can operate continuously thanks to a system of sassage (fig 4). This device is recommended on oil installations.

Description

The present invention relates to a device for filtering solid particles in a liquid by limiting the pressure losses to ensure a constant flow rate of this liquid

This device is recommended in the field of petroleum refining. The filtration of liquid hydrocarbons is traditionally ensured either by a filter located at the suction of a pump (fig 1) or by a line filter (fig 2). By their design, the filters are quickly clogged by a small amount of solid material (coke type) which causes serious disturbances of the installation. The problems caused by these disturbances are: pump cavitations caused by the loss of flow and pressure with risks of material breakage and fire. This results in production losses, maintenance costs and safety hazards for the responders.

In the case of a filter installed on a pump, this filter is a small basket {Fig. 1) fitted perpendicularly in the suction pipe of the pump. In disturbed operation {following a prolonged stoppage of the unit or following a pigging) this fiiter shows very quickly its limits and is quickly clogged despite a negligible amount of coke.

In the case of a filter mounted in line, this basket is larger (Figure 2) but the problem is that the little coke that comes in sticks to the grid suction side of the pump and obstructs fast enough. The report that is generally made to disassembly of this filter is that according to the pressure difference between the inlet and the outlet of the filter, it appears to fill while there is very little coke in the filter. inside. The proposed innovation is a concentric trap to separate solid waste into liquids (Fig. 3). Indeed, when starting units after a prolonged shutdown or following a "pigging", we are faced with a problem of more or less massive arrival of solid particles such as coke. The filters put in place are not designed to contain all these wastes so we have to clean them very often and a drop in the load of the unit is inevitable.

The design of the concentric trap is designed to channel the solid particles at its center to freely let the flow be on the sides of the filter by greatly limiting the pressure drop with a possibility of continuous purge via a sassage system (fig 4 The goal is to limit the maneuvers on the filters and pumps and thus capture maximum margins by a maximum and constant unit flow rate.

Claims (2)

1) Device for filtering solid particles in liquids (FIG. 3), characterized in that it comprises a conically-shaped grid basket in the upper part (1) which guides the impurities towards the cylindrical lower part (2) of smaller diameter. 2) Device according to claim 1 characterized in that this filter can operate continuously by an impurity bagging system by actuating the valve (1) to recover impurities in the lock (3) and then actuating the valve (2) to purge the airlock (3) (fig 4).