Heat recovery steam generator
AssigneeBabcock-Hitachi Kabushiki Kaisha
InventorIwao Kusaka
Life of this patent
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Abstract
Heat recovery boiler equipment comprising high and low pressure boiler drums and high and low pressure evaporators is disclosed. A recirculation pipeline system is also disclosed in which a control device is provided to control the flow rate of recirculated feed water to maintain a temperature below which cold corrosion occurs. The recirculation of feed water allows for a shorter starting time during restart. Additionally, pressure can be held at a predetermined value to prevent corrosion due to the intrusion of air.
Claims13
A heat recover boiler equipment, comprising:
- a high pressure boiler drum and a high pressure evaporator operatively connected together;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a low pressure economizer and a high pressure economizer;
- a first pipeline operatively extending between the outlet of said low pressure economizer and the inlet of said low pressure drum;
- a second pipeline extending between the outlet of said low pressure economizer and the inlet of said high pressure economizer, and bypassing said low pressure boiler drum;
- a source of feed water;
- pump means for receiving water from said source of feed water and pumping the water through said low pressure economizer and into each of said first and second pipelines;
- valve means in said first pipeline for controlling the flow of water into said low pressure boiler drum;
- second pump means in said second pipeline for pumping the water in said second pipeline that is downstream from said first pipeline into the inlet of said high pressure economizer;
- a third pipeline operatively extending between the outlet of said high pressure economizer and the inlet of said high pressure boiler drum;
- and
- valve means in said third pipelines leading to the inlet of said high pressure boiler drum for providing flow control into said high pressure boiler drum from said third pipeline.
A heat recovery boiler equipment, comprising:
- a high pressure boiler drum and a high pressure evaporator operatively connected together;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a low pressure economizer and a high pressure economizer;
- a first pipeline operatively extending between the outlet of said low pressure economizer and the inlet of said low pressure drum;
- a second pipeline extending between the outlet of said low pressure economizer and the inlet of said high pressure economizer, and bypassing said low pressure boiler drum;
- a source of feed water;
- pump means for receiving water from said source of feed water and pumping the water through said low pressure economizer and into each of said first and second pipelines;
- valve means in at least one of said pipelines for controlling the relative flow of water in said pipelines;
- second pump means in said second pipeline for pumping the water in said second pipeline that is downstream from said first pipeline into the inlet of said high pressure economizer;
- a third pipelines operatively extending between the outlet of said high pressure economizer and the inlet of said high pressure boiler drum;
- a recirculation pipeline operatively connected from the inlet of said high pressure economizer to the inlet of said low pressure economizer;
- and
- a flow control valve provided in said recirculation pipeline.
A heat recovery boiler equipment, comprising:
- a high pressure boiler drum and a high pressure evaporator operatively connected together;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a low pressure economizer and a high pressure economizer;
- a first pipeline operatively extending between the outlet of said low pressure economizer and the inlet of said low pressure drum;
- a second pipeline extending between the outlet of said low pressure economizer and the inlet of said high pressure economizer, and bypassing said low pressure boiler drum;
- a source of feed water;
- pump means for receiving water from said source of feed water and pumping the water through said low pressure economizer and into each of said first and second pipelines;
- valve means in at least one of said pipelines for controlling the relative flow of water in said pipelines;
- second pump means in said second pipeline for pumping the water in said second pipeline that is downstream from said first pipeline into the inlet of said high pressure economizer;
- a third pipeline operatively extending between the outlet of said high pressure economizer and the inlet of said high pressure boiler drum;
- a connecting pipeline for steam provided between said high pressure boiler drum and said low pressure boiler drum;
- and
- means for determining when steam pressure in said low pressure boiler drum is lowered to a predetermined value or less, to thereafter send high pressure steam to said low pressure boiler drum through said connecting pipeline, so that pressure in said low pressure boiler drum is held at the predetermined value or thereabove.
A heat recovery boiler equipment, comprising:
- a low pressure economizer;
- means for pumping feed water into said low pressure economizer;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a high pressure economizer;
- a high pressure boiler drum and high pressure evaporator operatively connected together;
- a pipeline for passing water from the outlet of said high pressure economizer to the inlet of said high pressure boiler drum;
- pipeline means for receiving water from the outlet of said low pressure economizer and feeding it to the inlet of said low pressure boiler drum and the inlet of said high pressure economizer, and including pump means for increasing the pressure of the water between said low pressure boiler drum and said high pressure economizer;
- a recirculation pipeline operatively connected from the inlet of said high pressure economizer to the inlet of said low pressure economizer;
- and
- a flow control valve provided in said recirculation pipeline.
A heat recovery boiler equipment, comprising:
- a low pressure economizer;
- means for pumping feed water into said low pressure economizer;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a high pressure economizer;
- a high pressure boiler drum and high pressure evaporator operatively connected together;
- a pipeline for passing water from the outlet of said high pressure economizer to the inlet of said high pressure boiler drum;
- pipeline means for receiving water from the outlet of said low pressure economizer and feeding it to the inlet of said low pressure boiler drum and the inlet of said high pressure economizer, and including pump means for increasing the pressure of the water between said low pressure boiler drum and said high pressure economizer;
- a connecting pipeline for steam provided between said high pressure boiler drum and said low pressure boiler drum;
- and
- means for determining when steam pressure in said low pressure boiler drum is lowered to a predetermined value or less, to thereafter send high pressure steam to said low pressure boiler drum through said connecting pipeline, so that pressure in said low pressure boiler drum is held at the predetermined value or thereabove.
A heat recovery boiler equipment, comprising:
- a low pressure economizer;
- means for pumping feed water into said low pressure economizer;
- a low pressure boiler drum and a low pressure evaporator operatively connected together;
- a high pressure economizer;
- a high pressure boiler drum and high pressure evaporator operatively connected together;
- a pipeline for passing water from the outlet of said high pressure economizer to the inlet of said high pressure boiler drum;
- pipeline means for receiving water from the outlet of said low pressure economizer and feeding it to the inlet of said low pressure boiler drum and the inlet of said high pressure economizer, and including pump means for increasing the pressure of the water between said low pressure boiler drum and said high pressure economizer;
- high pressure cyclone separator means for separating steam from water and being provided inside of said high pressure boiler drum at its inlet;
- low pressure cyclone separator means for separating steam from water and being provided inside of said low pressure boiler drum at its inlet;
- and
- each of said high and low pressure cyclone separators includes two separate cyclone separator portions, each portion having a compartment closed off from the water in its drum connected to receive the drum inlet water/steam and associated evaporator water/steam, respectively, and a centrifugal separator with an inlet connected to said compartment, a steam outlet connected to the steam area of its drum and a water outlet connected to the water area of its drum;
- a separate downcomer pipe connected between the water area of each boiler drum and its associated evaporator;
- and
- said cyclone separator portions being spaced from each other and said downcomer pipe in each of said drums.
Dependencies are inferred from the claim text.