Material conveying apparatus with shut down valves

Abstract

Disclosed is a system and method for conveying particulate material. A plurality of injector arrangements are arranged along the conveying pipeline, for injecting a continuous flow of conveying gas into the pipeline. Each injector arrangement is operable to increase the flow rate at which conveying gas is injected into the pipeline on of pressure conditions in the conveying pipeline indicative of locally decreased material permeability. Each injector arrangement comprises a piloted shut-off valve positioned between the flow rate adjustment arrangement and the conveying pipeline and operable to close in response to a received pilot signal indicative of a pressure condition in the conveying pipeline below a lower threshold pressure condition. The continuous flow of conveying gas injected by each of the injector arrangements prevents particulate material from entering any part of the injector arrangements, thereby reducing the risk of blockage of nozzles, injection pathway selection valves and the like. The continuous injection of conveying gas along the pipeline also maintains a degree of permeability particulate material in the pipeline and promotes stable conveying. The piloted shut-off valve of each injector arrangement is operable to independently detect a large pressure drop in the pipeline, and to close in order to store pressurized conveying gas in the injector arrangement and supply thereto.

Description

technical field [0001] The present invention relates to apparatus and methods for conveying particulate materials through pipelines, and in particular to conveying dense phase particulate materials using pressurized or vacuum techniques. Background technique [0002] Pneumatic conveying by pressure or vacuum is a technique used to convey granular materials along pipelines. These techniques are commonly used to convey material over long distances, typically in the range of 10m to 500m, and in some cases even further. Pneumatic conveying avoids the need to use conveyor belts, etc., which can be bulky and costly to maintain. [0003] Pneumatic conveying technology is particularly useful where material must be conveyed along complex paths or to multiple transfer points. These techniques also ensure that the particulate material is completely contained within the pipeline, which avoids the need to deal with dust or material contamination as the material travels along the convey...

AI Technical Summary

Problems solved by technology

[0013] Delivery speed and pressure may also be limited by allowing excess delivery gas pressure and volume to 'bypass' the material plug eg via internal grooved piping or external pressure relief valve controlled bypass circuits

Also, however, "bypass" arrangements can be prone to clogging and wear

In the case of internal bypass piping, repair or replacement can be particularly difficult and expensive

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