Water & energy reuse : From waste to resource
Francesco Suman explains how Alufluor found novel ways to recover resources by partnering with an EU-funded project
Over the past years , EU industries and academics have increasingly collaborated to develop environmentally friendly yet profitable products . The focus of research is increasingly shifting towards converting industrial waste into economically valuable resources , especially with raw materials and by-products from industries that operate at high temperatures , like chemicals .
An interesting example of this approach is found in Alufluor , a chemical company based in Helsingborg , Sweden . Alufluor produces aluminium fluoride , a crucial ingredient in the aluminium melting process . The company is quite well known in the industry for its compound production , especially given its purity rate of 97.5 %.
The production process generates a lot of wastewater , gases and chemical compounds that must be treated or removed . For example , drying generates hot vapours containing residual materials . Although these gases are filtered and scrubbed before flowing into the chimney , some waste still manages to escape .
Moreover , the process requires hot water to clean the reactors , wash the centrifuges and minimise any loss of fluorides in the process . Energy consumption is another critical issue : the whole industrial process requires a fair amount of power , mainly for drying aluminium fluoride and heating water .
Alufluor already recycles part of its heat , but the demand continues to be high . The company relies on a biogasdriven steam generator , representing one of its highest energy costs . As a result , it was one of 19 companies that took part in the iWAYS project , a research initiative funded by the European Commission .
In iWAYS , universities and companies collaborate to develop techniques for reducing emissions and recycling materials , heat and water . Some of these technologies will allow Alufluor to save and reuse approximately one third of the water it usually produces as waste and reduce its biogas consumption by 20 %.
“ iWAYS not only allows us to be more efficient and lower production costs , but it also gives us further strength in our sustainability brand ,” says Dan Turesson , a mechanical engineer who is the technical director at Alufluor .
Saving energy & reducing emissions
The heat pipe condensing economiser ( HPCE ) is the core technology developed by iWAYS scientists : it allows recovery of heat , water and materials . In addition , it is flexible enough to be adjusted to several industrial contexts .
The design was first developed by Professor Hussam Jouhara of Brunel University London . The University of Modena and Reggio Emilia worked on modelling , and EconoTherm , a UK company , manufactured the actual system .
Alufluor is about to install a multisection iWAYS HPCE , expecting to increase energy recovery and reduce chimney emissions . “ The condensation energy is much higher than the one you get from ordinary sensible heat exchangers ,” says Turesson .
“ Energy savings could double using iWAYS components . Consequently , we expect to reduce the need for steam used for heating washing water to a minimum . Of course , steam generators will remain as back-ups , but we can reduce biogas consumption by 20 % with these innovations .”
Emission reduction will be achieved by burning less fuel and sending cleaner gases to the chimneys . This is because condensation takes up a lot of fluoride particles , acting
54 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981