HOxyGas - Validation of an innovative automotive glass process: hot oxygen combustion and hot natural gas

PROJECT DESCRIPTION

BACKGROUND

Glass is a key element to many industries. In 2006, the world market for flat glass –in the automotive and other sectors - was estimated at around 42 million tonnes, which is equivalent to 4.2 billion square metres of glass with a thickness of 4 mm. Worldwide, the average yearly consumption is of 6 kg per person, which rises to 18 kg per person in Western Europe.

Flat-glass production requires a lot of energy and produces a large amount of greenhouse gas (GHG) emissions. Limiting these negative impacts has long been a challenge in the industry. One recent trend to improve environmental performance has been a shift from powering furnaces by oil to natural gas. These gas-powered furnaces - which now make up over 95% of the market – typically use gas air combustion technology.

This project operated at the AGC Flat Glass Czech plant of Retenice, which is a flat-glass production site with three furnaces using the float technique - in which a uniformly flat sheet of glass is produced by floating molten glass on a bed of molten metal. The specialism of this plant is the production of flat glass for the automotive division, architectural glass and laminated glass.

OBJECTIVES

The aim of the HOxyGas project was to demonstrate the technical feasibility of an innovative, cleaner technology for the production of clear and coloured flat glass for the automotive industry.

The proposed technology was based on the use of hot oxy-fuel combustion technology using only natural gas and oxygen. It involved pre-heating natural gas (450°C) for use as fuel and the use of pure oxygen (550°C) as oxidiser – instead of typical processes using air. The project aimed to demonstrate a reduction in both energy consumption and emissions of greenhouse gases (GHG) - in particular the well-known pollutants CO2, NOX, SOX and dust - compared to furnaces using air-combustion techniques.

Whilst the project aimed to demonstrate lowering the environmental impact of automotive glass production using the float technique, validation of the technology expected to be applicable also to other glass applications and other industrial sectors using natural gas furnaces.

RESULTS

The HOxyGas project demonstrated the maturity and full potential of the hot oxy-fuel combustion technology, using pure natural gas and O2 as oxidiser. It covered the engineering, construction, demonstration and validation of the furnace at Retenice, with a capacity of 500 t/day at low pull (for coloured glass) or 600 t/day at high pull (for clear glass).

The innovative technology achieved the following results:

Average 18.7% savings of melting energy at low pull versus the classical air furnace (the target was 18.4% at low pull and 19.7% at high pull);

Decrease of CO2 emissions by 5% (the target was 5.5%), equating to annual savings of 4 800 t;

Decrease of NOX emissions by 85% (the target was 79.2%), equating to annual savings of 745 000 t;

Decrease of SOX emissions by 82% (the target was 35.5%), equating to annual savings of 220 000 t;

Decrease of dust emissions by 83% (the target was 67.7%);

Since March 2016, the foreseen quality of glass was reached;

Production settings were validated;

Creation of 67 jobs and the long-term protection of many jobs at the project partners – the furnaces and other equipment should serve for about 15 years.

Replication of the piloted technology is now being considered for several plants within the AGC group. Adaptation should also be feasible to use the technology in other production processes that use melting furnaces, such as the steel industry or the cement industry, which is known for its vast CO2 emissions.

Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).

The HOxyGas project demonstrated the maturity and full potential of the hot oxy-fuel combustion technology, using pure natural gas and O2 as oxidiser. It covered the engineering, construction, demonstration and validation of the furnace at Retenice, with a capacity of 500 t/day at low pull (for coloured glass) or 600 t/day at high pull (for clear glass).

The innovative technology achieved the following results:

Average 18.7% savings of melting energy at low pull versus the classical air furnace (the target was 18.4% at low pull and 19.7% at high pull);

Decrease of CO2 emissions by 5% (the target was 5.5%), equating to annual savings of 4 800 t;

Decrease of NOX emissions by 85% (the target was 79.2%), equating to annual savings of 745 000 t;

Decrease of SOX emissions by 82% (the target was 35.5%), equating to annual savings of 220 000 t;

Decrease of dust emissions by 83% (the target was 67.7%);

Since March 2016, the foreseen quality of glass was reached;

Production settings were validated;

Creation of 67 jobs and the long-term protection of many jobs at the project partners – the furnaces and other equipment should serve for about 15 years.

Replication of the piloted technology is now being considered for several plants within the AGC group. Adaptation should also be feasible to use the technology in other production processes that use melting furnaces, such as the steel industry or the cement industry, which is known for its vast CO2 emissions.

Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).