CN203547811U

CN203547811U - Improved high temperature subcritical unit

Info

Publication number: CN203547811U
Application number: CN201320548970.6U
Authority: CN
Inventors: 冯伟忠
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-09-04
Filing date: 2013-09-04
Publication date: 2014-04-16
Anticipated expiration: 2023-09-04

Abstract

The utility model discloses an improved high temperature subcritical unit, which comprises a boiler with a superheater and a reheater, a steam turbine with a high pressure cylinder and an intermediate pressure cylinder, a main steam pipeline and a valve, a reheat steam pipeline and a valve and a high and an intermediate pressure by-pass valves, and is characterized in that temperature parameter grades of the superheater and the reheater of the boiler, the high and the middle pressure cylinders of the steam turbine, the main steam pipe, the valve and the reheat steam pipe and the valve and the high and the intermediate pressure by-pass valves are rated temperature or higher temperature parameter grades of an ultra supercritical unit, and the high pressure cylinder is arranged on the top portion of the boiler. The improved high temperature subcritical unit is relatively low in improvement cost, can greatly improve efficiency, is high in cost performance, and has obvious advantages.

Description

A kind of modified model high temperature Subcritical Units

Technical field

The utility model relates to a kind of modified model high temperature Subcritical Units, particularly, relates to the modified model high temperature Subcritical Units being transformed into by traditional Subcritical Units.

Background technique

Along with the development of material technology and the growing tension of world energy sources, the advantage of the relative Subcritical Units of supercritical unit/ultra supercritical unit is also more and more embodied, and has developed into the first-selection of domestic and international new-built unit at present.Existing subcritical, overcritical, ultra supercritical unit canonical parameter is respectively 16.7MPa/538 ℃/538 ℃, 24.1MPa/538 ℃/566 ℃, 27MPa～31MPa/600 ℃/600 ℃, overcritical/ultra supercritical unit is because its parameter is higher, and therefore its efficiency is relatively high.And in China, in order to improve electric structure, in recent years also started " upper large pressure is little " engineering, start gradually to eliminate middle-size and small-size highly energy-consuming unit, but it is still larger that subcritical generating set capacity accounts for total electricity electric motor power proportion, existing 300MW/600MW grade Subcritical Units total amount approximately reaches 300,000,000 kilowatts, in view of its working time not long, and be subject to the condition restriction such as power supply and fund, present stage can not be closed down these relatively medium-sized units of high energy consumption, comparatively ideal solution route is that the Subcritical Units of existing 300MW/600MW grade is undergone technological transformation to reduce its energy consumption, reduce pollutant emission, can meet again the demand of electrical production simultaneously.

But at present, for the transformation of this class Subcritical Units, traditional method is confined to carry out in the framework of the original parameter grade of unit the local flow improvement of some equipment or system more, and the advantage of transformation is not obvious, and investment is not high with the cost performance of energy saving profit.And in fact, along with the development of material technology, present stage, by transformation Subcritical Units, promote its parameter, there is not technical problem, on the one hand, this can obviously promote unit efficiency, on the other hand also can corresponding increase power plant retrofit cost, for example, promote the pressure parameter of unit, the wall thickness of overwhelming majority e-quipment and pipe is wanted corresponding increase, or select performance and the higher material of price, comprise such as boiler, steam turbine, heater, feed water pump, the equipment unit that pipe valve etc. need bear high pressure all needs to change comprehensively, transformation face is too wide and cost is huge, and in temperature-resistant situation, only solely improve pressure parameter, although efficiency of thermal cycle increases to some extent, but because vapor volume flow declines to a great extent, the internal efficiency of steam turbine also can obviously decline, therefore, also also not obvious to the lifting of unit overall efficiency, if adherence pressure simultaneously, temperature parameter, reforming cost can further promote again.Thereby, this type of transformation, though without technical problem, its transformation cost performance is low.In view of this, those skilled in the art is devoted to develop a kind of retrofitted unit that can significantly improve Subcritical Units efficiency, the reconstruction scope appropriateness, cost performance and have significant advantage.

Model utility content

In view of the demand of above-mentioned current thermal power plant Subcritical Units transformation and the deficiency of existing renovation technique, the utility model aims to provide a kind of Subcritical Units that can significantly improve Subcritical Units efficiency, cost performance and have significant advantage.

For achieving the above object, the utility model provides a kind of modified model high temperature Subcritical Units, comprise the boiler with superheater and reheater, there is high-pressure cylinder, the steam turbine of intermediate pressure cylinder, main steam line and valve, heat is steam line and valve and height again, intermediate pressure by-pass valve etc., it is characterized in that, the superheater of described boiler and reheater, the high-pressure cylinder of described steam turbine, intermediate pressure cylinder, described main steam line and valve, described heat is steam line and valve and described height again, the temperature parameter grade of intermediate pressure by-pass valve is rated temperature or the higher temperature parameter grade of ultra supercritical unit, wherein said high-pressure cylinder is all placed in boiler top.

The superheater of wherein said boiler and reheater, the high-pressure cylinder of described steam turbine, intermediate pressure cylinder, described main steam line and valve, described heat is steam line and valve and described height again, intermediate pressure by-pass valve can use high temperature austenite steel, ferrite steel, Martensite Steel or other can bear the material of higher temperature, the trade mark can be P91, T91, P122, P92, E911, FN616, HCM12, HCM12A, EM12, HCM9M, SA-387Gr22/22L, SA-387Gr91, SA-387Gr911, SA-1017Gr122, HT9 and HT91 and other can bear the trade mark of higher temperature material.

Wherein, described high-pressure cylinder disposes the generator of respective volume.Described ultra supercritical unit rated temperature parameter is representative temperature parameter grade, 600 ℃-620 ℃.

The utlity model has following advantage and effect:

1, the utility model, by keeping unit pressure parameter constant, promotes the temperature parameter grade of unit, and boiler side only need change superheater, reheater (primary superheater, the one-level reheater of low temperature parameter still can retain constant); Steam turbine place need change high, intermediate pressure cylinder; Be main steam line, valve in addition, heat is steam line, valve again, high, intermediate pressure by-pass valve.Generally speaking, change amount is few relatively, and in addition, pressure parameter is constant, and the wall thickness of pipeline also can be controlled, thereby total transformation face appropriateness, and cost performance is high.

2, the utility model has significantly promoted the temperature parameter of unit, on the one hand, can significantly promote unit thermal efficiency of cycle; On the one hand, in the situation that unit capacity is certain, pressure is constant in addition, and the lifting of temperature increases steam specific volume, and the internal efficiency of steam turbine also can correspondingly promote.

3, the utility model changes high, intermediate pressure cylinder because promoting unit temperature parameter, in identical reforming cost, also can obtain the income of current advanced person's the technology such as inner cylinder steam admission mode, flow passage component, blade profile optimization.For the height of 600MW grade, the internal efficiency of intermediate pressure cylinder, can be promoted to 92%, more than 94%.

4, the utility model does not change unit pressure parameter, and control mode, the method for operation of unit all do not change yet, and concerning unit operation personnel, its operation theory is also substantially unchanged.

5, the utility model also comprises reinforcement boiler foundation, the high-pressure cylinder of described Subcritical Units is arranged on the top of described boiler, to shorten the length of described main steam line, cold steam line again, this not only can greatly reduce the reforming cost of pipeline material, also can reduce the pressure drop of pipeline, further promote unit economy.

6, the utility model can be under the prerequisite that does not increase unit fuel consumption the generated output that significantly promotes corresponding raising unit of utilization ratio, not only energy-conservation and additional income.

Below the technique effect of design of the present utility model, concrete structure and generation is described further, to understand fully the purpose of this utility model, feature and effect.

Accompanying drawing explanation

Overcritical/ultra supercritical unit hear rate value under the equal capacity that Fig. 1 provides for same manufacturer.

Fig. 2 is the utility model embodiment one schematic diagram.

Embodiment

The utility model provides a kind of modified model high temperature Subcritical Units, comprise the boiler 1 with superheater 11 and reheater 12, there is high-pressure cylinder 21, the steam turbine 2 of intermediate pressure cylinder 22, main steam line 3 and valve, heat is steam line 4 and valve and height again, intermediate pressure by-pass valve, it is characterized in that, the superheater 11 of described boiler 1 and reheater 12, the high-pressure cylinder 21 of described steam turbine 2, intermediate pressure cylinder 22 and described main steam line 3 and valve, described heat is steam line 4 and valve and height again, the temperature parameter grade of intermediate pressure by-pass valve is rated temperature or the higher temperature parameter grade of ultra supercritical unit.

The superheater 11 of wherein said boiler 1 and reheater 12, the high-pressure cylinder 21 of described steam turbine 2, intermediate pressure cylinder 22, described main steam line 3 and valve, described heat is steam line 4 and valve again, described height, intermediate pressure by-pass valve can use the high temperature austenite steel that is usually used at present ultra supercritical power generation unit, ferrite steel, Martensite Steel or other can bear the material of higher temperature, the trade mark can be P91, T91, P122, P92, E911, FN616, HCM12, HCM12A, EM12, HCM9M, SA-387Gr22/22L, SA-387Gr91, SA-387Gr911, SA-1017Gr122, HT9 and HT91 and other can bear the material of higher temperature.

Wherein said high-pressure cylinder 21 is placed in boiler 1 top, and disposes the generator of respective volume.Described ultra supercritical unit rated temperature parameter is representative temperature parameter grade, 600 ℃-620 ℃.

Embodiment one

Take certain Subcritical Units as example, its main steam condition design load is 16.7MPa/538 ℃, and reheat steam temperature design load is also 538 ℃, and hear rate design load is 7862KJ/KWh.

According to follow-on high temperature Subcritical Units of the present utility model, boiler side installs superheater 11 and the reheater 12 by 600 ℃ of grade ultra supercritical power generation unit materials, made additional in original boiler 1 equipment Foundations; Steam turbine side, is replaced by steam turbine 2 height,

intermediate pressure cylinder

21 and 22 respective cylinder of 600 ℃ of grades; Meanwhile, by boiler 1 to the pipeline 3 of the main steam between steam turbine 2, valve and heat pipeline 4, valve and height, the relevant device that intermediate pressure by-pass valve is all replaced by 600 ℃ of grade material of steam again.Unit design pressure is constant, remains on 16.7MPa, and the design temperature value of main steam, reheated steam is all risen to 600 ℃.

(600 ℃ temperature-resistant under) the hear rate value of different pressures and hear rate design load 7602KJ/KWh of supercritical unit (23.96MPa/538 ℃/566 ℃) during ultra supercritical unit sliding pressure operation under the equal capacity unit providing according to same manufacturer, as shown in Figure 1.Utilize interpolation, the unit hear rate value that easily obtains improved high temperature Subcritical Units (steam parameter 16.7MPa/600 ℃/600 ℃) is about 7492KJ/KWh.As can be seen here, by the present invention, traditional Subcritical Units is transformed into high temperature Subcritical Units, can make its hear rate value be reduced to 7492KJ/KWh by former 7862KJ/KWh, and this hear rate level is obviously better than the supercritical unit of same manufacturer, be only second to current ultra supercritical unit.

In addition,, by strengthening boiler foundation, high-pressure cylinder 21 is placed on to boiler 1 and pushes up, and configure the generator of respective volume.From boiler superheater main steam out, directly enter the high-pressure cylinder acting boiler top, the steam discharge of high-pressure cylinder is that cold steam again enters boiler reheater and further absorbs heat, and the heat after heat absorption again steam enters the intermediate pressure cylinder that is arranged in conventional steam turbine generator firing floor again and continues acting.As shown in Figure 2, the steam turbine that wherein A is ordered comprises high-pressure cylinder 21, and B point steam turbine comprises intermediate pressure cylinder 22 and low pressure (LP) cylinder 23.

This mode of execution has greatly shortened main steam line and cold steam line again, has not only reduced high alloy pipeline cost of material, and has reduced pressure and the radiation loss of main steam line and cold steam line again, has improved unit economy.By this mode of execution, traditional Subcritical Units is transformed into high temperature Subcritical Units, can make its hear rate value be reduced to 7492KJ/KWh by former 7862KJ/KWh, simultaneously, owing to further high-pressure cylinder being placed on boiler top, can reduce pressure and the radiation loss of main steam line and cold steam line again, be converted to hear rate, can further be reduced to 7474KJ/KWh.

More than describe preferred embodiment of the present utility model in detail.The ordinary skill that should be appreciated that related domain just can be made many modifications and variations according to design of the present utility model without creative work.Therefore, all technician in the art comply with design of the present utility model on the basis of existing technology by the available technological scheme of logical analysis, reasoning, or a limited experiment, all should be in by the determined protection domain of claims.

Claims

1. a modified model high temperature Subcritical Units, comprise the boiler with superheater and reheater, there is the steam turbine of high-pressure cylinder and intermediate pressure cylinder, main steam line and valve, heat is steam line and valve and height again, intermediate pressure by-pass valve, it is characterized in that, the superheater of described boiler and reheater, the high-pressure cylinder of described steam turbine and intermediate pressure cylinder, described main steam line and valve, described heat is steam line and valve and described height again, the temperature parameter grade of intermediate pressure by-pass valve is rated temperature or the higher temperature parameter grade of ultra supercritical unit, wherein said high-pressure cylinder is all placed in boiler top.

2. modified model high temperature Subcritical Units as claimed in claim 1, it is characterized in that, the superheater of described boiler and reheater, the high-pressure cylinder of described steam turbine and intermediate pressure cylinder, described main steam line and valve, described heat is steam line and valve again, described height, intermediate pressure by-pass valve use high temperature austenite steel, ferrite steel or Martensite Steel material, and the trade mark is P91, T91, P122, P92, E911, FN616, HCM12, HCM12A, EM12, HCM9M, SA-387Gr22/22L, SA-387Gr91, SA-387Gr911, SA-1017Gr122, HT9 or HT91.

3. modified model high temperature Subcritical Units as claimed in claim 2, wherein, described high-pressure cylinder disposes the generator of respective volume.

4. modified model high temperature Subcritical Units as claimed in claim 3, wherein, described ultra supercritical unit rated temperature parameter is representative temperature parameter grade, 600 ℃-620 ℃.