RETROFITTING PACKAGE FOR POWER FIRED HIGH PRESSURE BOILER WITH UPSTREAM GASTURBINES

Obiettivo

The aim of the project is to demonstrate the possibility of fuel conservation by retrofitting existing industrial cogeneration plants (gas fired power boiler with back pressure turbine) to combined cycle cogeneration plants in adding a gas turbine in front of the boiler. Simultaneously the total amount of NOx-emissions is reduced.
In addition, a special configuration is applied within this project for further NOx-reduction of the CCP.
Primary fuel saving exceeds 45,000 MWh/year and the payback time is 3,8 years. The emission rate of NO2 is only 60% of the emission admitted by the German environmental protection regulations for steam and gas cogeneration plants. Those of CO are nearly negligible and do not even reach at peak emission 5% of the admitted value.
The purpose is to improve the power output of conventional cogeneration plants by retrofitting the plant with a gas turbine generator set (GT).
Economic investigations and sensitivity analyses of industrial plants point to the superiority of gas fired cogeneration plants with a power heat ratio of 0.3 in the range from 15 to 60 MW heat demand. Conventional cogeneration plants can easily be improved by placing an additional gas turbine generator set in front of the high pressure boiler to replace the F.D. fan. The gas turbine exhaust, which contains sufficient oxygen for additional power burning, is fed directly to the conventional gas or oil burners. The mass flow through the boiler rises by 10%. The boiler efficiency is diminished by only 1%. In spite of this loss, the total efficiency of the additional power generation lies in the range of 83% depending on the site of the gas turbine. Applications of this kind were realized with success in the past by public utilities for powerproduction (400 - 700 MW) only.
The development of a new generation of gas turbines in the rnage of 0.8 - 8 MW output with high thermal efficiency promises economic operation of conventional cogeneration plants or steam generation plants with upstream gas turbine generator sets.
The implementation of the complete retrofitting package within an existing plant comprises the following components :
- gas-turbine generator set - new burner equipment
- new boiler - electrical tie-up
- flue gas piping - remote control equipment
For the pilot installation a gas turbine generator set of 3.5 MW was selected.
The retrofitting package with upstream gas turbine improves in the plant electricity production of the factory and reduces electricity purchase from public utility.
One (1) MW electric power, generated in a cogeneration system consumes 1.2 MW fuel (cogeneration efficiency 83 %). One (1) MW electric power, generated in a condensingsteam power plant of a public utility consumes 2.6 MW fuel (efficiency 38%). Substituing public utility power cogenerated power conserves 1.4 MW primary energy per MW electric power.
For the selected pilot plant of a paper mill the following balance is given :
Additional power generation 27 000 MWh/y
Substituted fuel consumption 32 000 MWh/y
In respect to admissible NOx-emissions, in the FRG combined cycle plants are treated like gas fired power stations (200 mg/m3).
With conventional cycles this limits are hardly met without secondary emission control measures. A special heat cycle using an exhaust gas cooler was developed to reduce NOx-emission and to compensate heater surfaces.
The test phase will mainly deal with the basic research dissociation of GT-Nox and of forming new NOx in the flame of the power burner.

Programma(i)

ENG-ENDEMO C - Programme (EEC) of demonstration projects and industrial pilot projects (EEC) in the energy field, 1985-1989

Argomento(i)

3.3 - ENERGY INDUSTRY

Invito a presentare proposte

Data not available

Meccanismo di finanziamento

DEM - Demonstration contracts

Coordinatore

KONSORTIUM MCH

Contributo UE

Nessun dato

Indirizzo

C/O ENERGIE UND UMWELTTECHNIK STEINBEISSTRASSE 6
7250 LEONBERG
Germania

Costo totale