Multiple pass economizer and method for SCR temperature control
    1.
    发明授权
    Multiple pass economizer and method for SCR temperature control 有权
    多通道节能器和SCR温度控制方法

    公开(公告)号:US07637233B2

    公开(公告)日:2009-12-29

    申请号:US11542413

    申请日:2006-10-03

    IPC分类号: F22G1/02

    CPC分类号: F22D1/12

    摘要: A control system for maintaining a desired heat exchanger outlet flue gas temperature across a range of boiler loads. The heat exchanger includes a plurality of tubular configurations in heat exchange contact with the flue gas with each tubular configuration having a separate feedwater inlet. Flue gas temperature control is achieved by modulating the feedwater flow rates through the tubular configurations. In a system having two tubular configurations, the overall heat transfer capacity of the heat exchanger may be reduced to maintain the desired heat exchanger outlet flue gas temperature by reducing feedwater flow through one tubular configuration and overflowing the other, while maintaining the total flow of feedwater through the heat exchanger substantially constant.

    摘要翻译: 一种用于在一定范围的锅炉负荷下维持期望的热交换器出口烟气温度的控制系统。 热交换器包括与烟道气热交换接触的多个管状结构,每个管状构造具有单独的给水入口。 通过调节通过管状构造的给水流速来实现烟道气体温度控制。 在具有两个管状构造的系统中,可以减少热交换器的总传热能力,以通过减少通过一个管状结构的给水流量并溢出另一个而保持所需热交换器出口烟气温度,同时保持给水总流量 通过热交换器基本上恒定。

    Multiple pass economizer and method for SCR temperature control
    2.
    发明申请
    Multiple pass economizer and method for SCR temperature control 有权
    多通道节能器和SCR温度控制方法

    公开(公告)号:US20070261647A1

    公开(公告)日:2007-11-15

    申请号:US11542413

    申请日:2006-10-03

    IPC分类号: F22D7/00

    CPC分类号: F22D1/12

    摘要: A gas temperature control system for maintaining a desired economizer outlet gas temperature across a range of boiler loads comprises a plurality of tubular configurations having surfaces that are in contact with the flue gas. Each tubular configuration, preferably, comprises a plurality of serpentine or stringer tubes arranged horizontally or vertically back and forth within the economizer, and each tubular configuration having a separate feedwater inlet. Heat transfer from the flue gas is accomplished by controlling the feedwater flow rates through the tubular configurations. In a temperature control system having two tubular configurations, the overall heat transfer capacity of the economizer may be reduced to maintain the desired economizer outlet gas temperature during low boiler loads by reducing feedwater flow through one tubular configuration and by overflowing the other tubular configuration, such that total flow of feedwater through the economizer is maintained substantially constant. Feedwater flow rate entering the economizer may be used to engage/disengage the economizer water internal proportion or bias system. Once engaged, the measured feedwater flow to the economizer is used to generate a proportioned or biased flow rate demand signal. The demand signal is then compared to the measured underflow proportioned or biased flow rate. If there is a difference between the demand signal flow rate and the measured flow rate, control valve(s) modulating the proportioned or biased flow is/are adjusted.

    摘要翻译: 用于在一系列锅炉负荷下保持期望的节能器出口气体温度的气体温度控制系统包括具有与烟道气接触的表面的多个管状构造。 每个管状构造优选地包括在节能器内水平或垂直地前后排列的多个蛇形管或纵梁,并且每个管状构造具有单独的给水入口。 通过控制通过管状构造的给水流速来实现来自烟道气的热传递。 在具有两个管状构造的温度控制系统中,可以减少节能器的整体传热能力,以便在低锅炉负荷期间通过减少通过一个管状构造的给水流量和溢出其它管状构造来维持期望的节能器出口气体温度,例如 通过节能器的给水的总流量保持基本恒定。 进入节能器的给水流量可用于接合/分离节能器内部的比例或偏压系统。 一旦接合,使用测量到节能器的给水流量来产生比例或偏压的流量需求信号。 然后将需求信号与测量的下流比例或偏压流量进行比较。 如果需求信号流量和测量流量之间存在差异,则调节调整成比例或偏置流量的控制阀。