Making green choices

Tata Chemicals Europe is continuously improving its manufacturing processes to become more energy efficient and climate sensitive

At Tata Chemicals Europe (TCE), the UK arm of Tata Chemicals, efforts to cut greenhouse gas (GHG) emissions began way back in 2000 when the company commissioned a gas-fired combined heat and power plant (CHP) at its Northwich West site. The plant, set up at a cost of £150 million, marks the beginning of a series of decisions that have helped TCE grow without adding to the emissions trail.

Over the past decade or so, the company has relied increasingly on clean fuel and alternative energy to run its plants. It has built up a portfolio of products that help customers control their carbon emissions, and in the pipeline is a £300 million sustainable energy plant that will be fuelled by waste and biomass. All of this has made TCE an important player in Europe’s carbon reduction journey and invaluable to the overall Tata Chemicals’ climate change programme. Its story is about how a few well-deliberated measures can make a big impact on the environment.

Green line
TCE is one of the world’s leading manufacturers and suppliers of sodium carbonate, sodium bicarbonate and associated alkaline products. It produces around one million tonnes of its primary product sodium carbonate – or soda ash – each year. With more than 1,500 customers worldwide including glass makers, bath additive producers, sugar extractors and suppliers of haemodialysis treatments, TCE reaches out to a diverse set of businesses and people. By choosing to be ecologically sensitive in the way it manufactures these products, it indirectly influences its customers to behave in the same manner. Besides, its products are used to make solar panels and glass, which is used in green buildings, thereby helping support a green way of life.

Energy management
TCE's production processes are energy-intensive and require a large amount of steam. Every year 2.5TWh (2.5 million megawatt hours) of heat energy is required to run the business. By switching to alternative energy sources and making the production process itself more energy efficient, the company has been able to significantly bring down its GHG emissions.

The main change has been switching from coal to a gas-fired CHP in 2000. More recently a new decarbonator was commissioned at the same site. Designed in-house, the new unit has cut the energy used in the sodium bicarbonate production process by 5 per cent.

TCE has also made the production processes more energy efficient through the use of improved distributed control systems and energy-efficient distillation columns. Distributed control systems helps monitor the steam usage and distillation columns, required to separate the ammonia from the liquor by injection of steam into the column, help control its usage. The two together help cut down the energy used in the process.

Sustainable energy

The UK government has set itself a target of 80 per cent reduction in carbon emissions by 2050 and is promoting waste-fuelled power plants as an important means of reaching these targets. TCE has proposed setting up a sustainable energy plant which will go a long way in meeting these targets. The plant is being developed in alliance with E.ON, a company with a strong track record of developing, building and operating sustainable energy plants to the highest technical and environmental standards. It will be built on the site of a disused coal-fired power station at Northwich East and will use approximately 600,000 tonnes of fuel per year to produce up to 60MW of electricity and around 100 tonnes per hour of steam. The facility will be regulated and monitored by the Environment Agency to ensure that it operates in accordance with strict legislation and environmental standards. It will use solid fuel made from waste materials that would otherwise go to landfill. Through the ‘energy recovery’ process, these materials will be treated to produce clean, sustainable power.

Future impact
TCE plans to build a sustainable energy plant at its Northwich East site, which will turn pre-treated waste into electricity and steam (see box: Sustainable energy). The plant will save approximately 200kt per year of CO² and will result in the company having one of the lowest carbon footprints, lower than that of any ash producer, natural or synthetic, in the world. Expected to be ready by 2015, at an investment of £300 million, the plant will:

	Cut CO2 emissions by switching to a non-fossil fuel energy source.
	Cut methane emissions by burning waste to recover energy instead of burying in a landfill site.
	Meet a third of the company’s high energy requirements, lower costs and help secure the future of the TCE business by making it less reliant on gas supplies.

The sustainable energy plant will supply renewable heat and electricity (see box: What is renewable energy) for both sites in Northwich. And in the years to come, it will not only help the environment at large but also make TCE among the world’s most competitive soda ash producers in the world.

What is renewable energy?

Renewable energy is an inexhaustible source of energy that comes from natural resources such as sun, wind, etc. It also includes: The ‘energy from waste’ or ‘energy recovery’ process, which takes materials that would otherwise go to landfill and uses them to produce clean, sustainable power. Biomass, which is a plant-derived material.     Switching to renewable energy will help tackle the challenge of climate change in a big way because: A 60-MW power station, such as TCE's proposed new sustainable energy plant, can produce enough energy for 45,000 homes. Waste is an excellent fuel and there is an abundant supply of potential fuel for a sustainable energy plant. Using waste-derived fuel as a replacement for fossil fuels results in lower climate-damaging emissions of CO2 and methane. Around 50 per cent of domestic waste in the UK consists of biomass plant-derived materials. In the UK, methane emissions from biodegradable waste in landfill account for 40 per cent of all methane emissions and three per cent of all greenhouse gas emissions. Methane is 23 times more damaging than carbon dioxide.

Dr Ladan Iravanian
Business development director, Tata Chemicals Europe

Sourced from Quest, Volume 5 , November 2010, in-house Publication of Tata Quality Management Systems.