Background INEOS's most important product is paraformaldehyde, which is produced from formaldehyde. By-products are hexamine and an aqueous, low-concentrate formaldehyde solution. Large amounts of fresh air are needed for the spray-drying production process, and also for product handling in dryers, the mill and for transportation through the entire plant. The INEOS paraform (paraformaldehyde) plant currently emits some 38 000 m3/h of waste air containing some 70-80 tonnes/yr of methanol (~28 mt/y), ammonia (~40 mt/y), formaldehyde (0.5 mt/y) and malodorous substances (5-6 mt/y). This exceeds Germany's legal limits under the “Clean Air Act” ("TA-Luft"), but to date no feasible technology has existed to improve the situation, so the plant has been running with an exemption permit. Recent tests carried out by INEOS in a laboratory and a pilot plant showed that emission levels could be considerably reduced by the implementation of a more efficient plasma catalytic waste air treatment. Objectives The objective of the Waste air treatment project was to set up a plasma catalytic waste air treatment module on a large-scale in the paraformaldehyde plant of beneficiary INEOS, a first for this type of industry. The project aimed to reduce emissions of methanol, ammonia, formaldehyde and malodorous substances; reduce annoying odours in the neighbourhood and cut resident complaints by 50%; reduce acidic and eutrophic nitrogenous contaminant emissions into the air, soil and water; reduce risks for the health of people living nearby, as well as for local ecosystems; and optimise energy usage by heat recovery to warm the input air stream. Results The Waste air treatment project successfully set up a prototype plant to purify the production exhaust air at the paraform (paraformaldehyde) plant of beneficiary INEOS. The demonstration plant removed formaldehyde, methanol, ammonia, nitrous compounds and ozone far below the legal limit values, and odour emissions were significantly reduced. The technology will probably become a new BAT (Best Available Technique). The plasma catalytic technology also has significant environmental and economic advantages compared to other treatment methods for formaldehyde. The prototype plant has been operating since June 2014, keeping emissions well below industry thresholds. Emissions before the LIFE project were 10 mg/m³ for formaldehyde, 150 mg/m³ for methanol and 300 mg/m³ for ammonia. Using the new catalytic plasma process for waste air purification, formaldehyde emissions were nearly eliminated (below 1 mg/m3), and methanol and ammonia were below 20 mg/m3 and 30 mg/m3, respectively. Nitrous compounds and ozone could not be detected in the treated air stream, and the air emissions from the plant did not smell anymore. The emissions from the paraform plant are now reduced annually by about 4 tons of formaldehyde, 25 tons of methanol and 15-20 tons of ammonia. The new technology is also cheaper than conventional solutions for treating formaldehyde. Refinements to the process were made throughout the project. At first, the catalyst was unstable, but this problem was solved by using a different surface material and a structural change (from pellets to a honeycomb structure). During the re-design, the energy recovery was greatly enhanced, while further optimisations to the plant included a decrease in the operating temperature of the catalyst, and correspondingly a further decrease in energy consumption without reducing the good purification performance. The plant improves the local environment for both workers and people living in nearby neighbourhoods, by reducing the emission of odours, hazardous substances and ozone, which equates to an improved quality of life and less health problems. The project also contributes to environmental improvement due to the very low NOx emissions, which help reduce nitrogen levels in the surrounding soil and groundwater. The low temperature plasma catalytic process uses comparatively little energy and therefore has low CO2 emissions. In addition, the technology permits recover of up to 90% of the process’s consumed energy in the form of heat to be re-used in the treatment, thus increasing the sustainability of the technique. Without the project’s novel purification solution for waste air treatment, the whole site would probably have been closed down with the loss of 140 jobs. With the new waste air treatment process, the plant can expand and still comply with the threshold emission values, which in turn can create new jobs. Furthermore, the related production of burners and catalysts was contracted to RELOX in Bremerhaven, an economically weak region with a high unemployment rate. Due to the stricter legislation for formaldehyde in waste air (it is being reclassified European-wide as a “cancer causing substance" with significantly lower emission thresholds), the pressure on companies using such substances will grow. The project therefore has a high demonstration value. Project beneficiary INEOS, as a supplier of paraformaldehyde, also has a role as technical adviser for handling such substances, including waste air treatment. Therefore, the prototype plant is an ideal showcase to demonstrate this solution to potential further users. The project also demonstrated how such a plant can be optimised to operate with a minimum of energy consumption and a long-lasting catalyst. Five to eight replications of similar size were estimated for the ten years following the project. The project will probably set a new state-of-the-art concerning formaldehyde treatment in waste air. This could have a massive impact on users of formaldehyde, which often are SMEs, where the high costs of waste air treatment can impair competitive production. The project was awarded the Best Environmental prize 2014 by the Minister of Environmental of Rheinland-Pfalz. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).