Solids flow meter for integrated boiler control system

Abstract

A combustion control system [100] for a combustion system [7] having a plurality of fuel pipes [5]. The combustion control system [100] including a plurality of flow meters [10], a controller [8], fuel flow controls [11] and secondary air controls [61,62,72]. Each meter [10] is adapted to monitor flow of fuel within a respective one of the fuel pipes [5] by sensing a pressure field within the fuel pipe [5]. A controller [8] receives the flow information from each of the flow meters [10], to evaluate performance of the combustion system [7]. Controller [8] also providing control information for controlling the flow of secondary air dampers [61,62,71] into the combustion system [7], and optionally controlling the flow of fuel in each fuel pipe [5].

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]This invention relates to coal-fired combustion systems, and more particularly to more efficient coal-fired combustion systems that accurately measure fuel flow and adjust secondary air flow based upon the measured fuel flow.[0003]2. Description of the Related Art[0004]In various coal-fired combustion systems, such as a boiler or furnace, a pulverizer is used to feed pulverized coal to the combustion system through a number of fuel pipes. Typically, the flow rate of coal through the fuel pipes cannot be accurately measured with intrusive flow meters due to the erosive environment within the coal pipe. Periodic measurements are used to adjust riffle distributors to provide approximately the same fuel flow through each fuel feed lines, balancing the lines.[0005]Fuel line imbalance can cause improper air / fuel ratio and improper combustion in various portions of the combustion system. This affects carbon loss and can lead t...

AI Technical Summary

Benefits of technology

[0010]At least one secondary air flow control [61,62,71] receives the control information and controls the secondary air flowing into said furnace [7] creating more efficient combustion and reduced emissions.

Problems solved by technology

Typically, the flow rate of coal through the fuel pipes cannot be accurately measured with intrusive flow meters due to the erosive environment within the coal pipe.

Fuel line imbalance can cause improper air / fuel ratio and improper combustion in various portions of the combustion system.

This affects carbon loss and can lead to production of undesired emissions such as carbon monoxide (CO), various nitrogen compounds (NOx), as well as various volatile organic compounds and others.

Such emissions can cause a plant to be out of emissions compliance or run inefficiently.

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