Environmental protection

Environmental protection goals

We aim to use all natural resources as efficiently as possible while reducing emissions into the environment to the greatest extent possible. The management tool we use for this purpose is our continuously updated integrated management system. Sophisticated data management systems also help us identify and realize potential efficiency improvements and keep the environmental impact of our production activities to a minimum.

Covestro aims to halve direct and indirect emissions of greenhouse gases per metric ton of product by 2025 compared with the 2005 base year levels. In addition, our goal is to halve the specific energy consumption of our production facilities by 2030 compared with the same base year. This improvement in energy efficiency is a key lever for significantly lowering our specific greenhouse gas emissions.

Optimizing energy consumption

Our production volume fell by 0.5% in 2019. Energy consumption also decreased over the same period. Although total energy input rose by 0.3%, the calculation-based equivalent primary energy consumption stated below fell by 1.0%. As a result, the specific energy consumption figure improved by 0.5% over the previous year. Compared with the base year 2005, this represents an improvement of 36.0%.

Along with other factors, our STRUCTese® energy efficiency system contributed significantly to this result over the years.

This system developed by Covestro compares actual energy consumption in production with the realistic potential optimum. Eliminating inefficiencies results in permanent energy savings. STRUCTese® comprises many different steps that can be used to identify potential improvement measures – from analysis to monitoring and benchmarking. These are known at Covestro as STRUCTese® projects. The system, which has been gradually rolled out since 2008, is now used in many of our energy-intensive production facilities worldwide and will be implemented in other facilities in the future.

Equivalent primary energy consumption comprises the fuels used directly at Covestro for generating energy (primary energy) plus externally sourced energy (secondary energy), such as electricity, steam and refrigeration. The latter are converted into the energy required to generate them.

Every year, projects are implemented under STRUCTese® that bring about lasting energy savings. An example is the optimization of the polycarbonate plant in Map Ta Phut (Thailand) in which recycled solvents can be reused within the plant from this year onward. Steam usage was therefore cut by more than 15,000 MWh of primary energy in 2019, which is the equivalent of reducing emissions by some 4,500 metric tons of CO₂. At the Baytown (United States) site, the electrolytic cells for chlorine production have been continually retrofitted to the newest technology used at the site since 2016, which lowered electricity requirements by around 20,000 MWh of primary energy in 2019 alone and reduced CO₂ emissions by some 3,000 metric tons. Covestro carried out various other projects in 2019, resulting in annual savings totaling 145,000 MWh of primary energy corresponding to 28,000 metric tons of CO₂ emissions. Combined, all the projects implemented since the introduction of STRUCTese® in 2008 result in lasting annual reductions totaling 2.22 million MWh of primary energy and 680,000 metric tons of CO₂.

These energy savings become evident particularly when viewing the significant fall in specific energy consumption in production since fiscal 2005 (see chart).

Development of specific energy consumption

(Change in specific primary energy consumption per metric ton of product, compared with the baseline year, in %)¹

Greenhouse gas emissions in detail

Direct emissions from our plants (Scope 1) are determined at of Covestro’s production locations and relevant administrative sites. Emissions are calculated based on the specific activity rates, e.g. of the fuels used, and the relevant material parameters. In addition to CO₂, the calculation includes nitrous oxide (N₂O), methane (CH₄) and partly fluorinated hydrocarbons.

Indirect emissions (Scope 2) are calculated in accordance with the methods outlined in the GHG Protocol and are based on the energy used and the corresponding production site-specific emissions factor. If there is no specific factor available, the International Energy Agency’s (IEA) country-specific emissions factor is used among others for the calculation. The factors are taken from the IEA Emissions Factors (2018 Edition), ©2019 IEA Online Data Services. Since the 2018 reporting year, Scope -2 emissions have been reported using the location-based method and the market-based method in accordance with the most recent requirements of the GHG Protocol (dual reporting). The new form of presentation does not affect comparability with prior-year figures with regard to the two long-term corporate goals of lowering specific energy consumption and specific greenhouse gas emissions.

Total greenhouse gas (GHG) emissions fell by 10.3% from the previous year, with direct greenhouse gas emissions up by 2.4% and indirect greenhouse gas emissions down by 13.2%. At our major production sites, which account for over 95% of our energy consumption, the production volume fell by 0.5% in 2019. Specific emissions consequently decreased by 10.2% compared with the previous year.

Other direct emissions into the air

In addition to greenhouse gases, Covestro’s business activities result in other emissions into the air, e.g., from burning fossil fuels in order to generate electricity and steam. Emissions are also recorded and analyzed as part of determining the Group’s environmental impact. The impacts are assessed annually in the environmental management process with the Chief Technology Officer (CTO). While carbon monoxide emissions (–11.3%) and nitrogen oxides (–14.4%) fell, sulfur dioxide emissions remained at the previous year’s level. Dust emissions increased by 19.7%. The reported figure for NMVOC emissions rose by 11.3% year over year. The key reason for this increase was a data collection methodology we refined this year that now for the first time includes measurement of diffuse NMVOC emissions from improper seals or leaks, as well as those from defined direct sources (such as chimneys or ventilation ducts). The data is collected according to the locally applicable official standards in each case.

Water consumption and usage

For our production sites, the availability of and access to clean water is vital. As part of our Corporate Commitment on Water issued in 2017, we initiated and have continually updated a risk assessment of our production sites covering water availability, quality and accessibility.

Once again in this reporting period, we refined our risk-based water approach and implemented it at all sites currently exposed to a high risk of water stress. Water stress includes water scarcity as well as other factors such as water quality and access to water. 16% of our total water consumption is at sites located in current water stress regions.

By analyzing local water management at sites, risks can be spotted at an early stage and potential for improvement can be identified. For instance, the production site in Antwerp launched a program to decrease water consumption and increase the percentage of recycled water used.

Use of water in 2019 (million cubic meters)

At 256 million cubic meters, total water consumption in the Group is lower than in the previous year. Once-through cooling water accounts for 80.2% of this figure, which consequently represents most of the water used by Covestro in 2019. This water is only heated and does not come into contact with products. It can be returned to the water cycle without further treatment in line with the relevant official permits. The total volume of once-through cooling water was 205 million cubic meters in the reporting year.

Some of the water used can be recycled in various ways. For instance, recycled water can be used again in the same process multiple times, e.g., for cleaning or cooling purposes. It is also possible to reuse water from upstream processes in subsequent steps. This permits corresponding quantities of fresh water to be conserved each year. In the reporting period, the volume of recycled water used stood at approximately 5 million cubic meters, around the same share as the prior year.

Wastewater

Our goal is to minimize wastewater emissions, which depend largely on our production volumes and the current product portfolio, as much as possible.

The volume of process wastewater decreased by 6.4% year over year. The proportion of process wastewater purified at a wastewater treatment plant operated by Covestro or a third party amounted to 74.8% worldwide. Following careful analysis, another 24.9% was categorized as environmentally safe and returned to the water cycle. The remainder (around 0.3%) was disposed of mainly through incineration. In the reporting year, the percentage of evaporation losses dropped by 10.8% to 10 million cubic meters.

Total organic carbon (TOC) emissions into wastewater decreased by 5.1% compared with the previous year, while the volume of phosphates discharged was down 7.3%. The amount of nitrogen compounds discharged also fell by 7.0%, and the volume of inorganic salts discharged into wastewater was down 6.2%. During the year under review, the volume of heavy metals emitted rose by 1.8%.

Work on the Re-Salt joint project aimed at recycling salt-laden industrial process wastewater promoted by the German Federal Ministry of Education and Research (BMBF) since 2016 is coming to a close. A pilot plant has been successfully operated at the Uerdingen site since mid-2019 that increases the salt concentration in process wastewater. In addition, insights into quality assurance gleaned from the project have already been transferred to the Caojing site in China. Salt-laden process wastewater is not used by Covestro there, but instead supplied to an external electrolyzer operator who in turn uses it to manufacture chlorine.

Waste and recycling

In nearly all countries the law stipulates exhaustive reporting on waste volumes and waste streams, a requirement complied with accordingly by Covestro’s sites. In Germany, for example, there are waste-tracking procedures between the waste producer and the waste disposer that enable end-to-end traceability of the waste flows. We classify waste in the individual waste categories and the corresponding methods of disposal according to the locally applicable definitions. Based on this documentation, we prepare and evaluate our waste balance, which is published annually.