By integrating new solutions into existing company structures on two levels and exploiting new solutions a resource efficient water management was realized. The INSPIREWATER approach demonstrated how a generic framework for process industries can be used and further developed to provide a holistic approach for water management, including life-cycle thinking and resource efficiency as key performance indicators.
Water management
The scope was to develop a model and a framework for a holistic water management and to define relevant performance metrics (key performance indicators, KPI) that support the activities within water saving and process optimisation. As part of the holistic approach followed during INSPIREWATER, in-depth Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) analysis were conducted to evaluate the performance of the technologies from an ecological and economic point of view. The results of this assessment can be used to detect hot spots, to find efficient optimization potentials as well as to evaluate different options according to their environmental effects. Furthermore, the results of a LCA can easily be combined with economic figures, allowing interpretation of the eco-efficiency of systems and to determine how money is best invested.
Demonstration Arcellor Mittal
ArcelorMittal operates a Rail Mill and Heavy Plate Mill in Gijon, Spain with a cooling water circuit of 7000 m3 of holding volume. In the Rail Mail cooling water circuit occurs corrosion, scaling and biological activity caused by unavoidable production-related intake of oil, temperature, particle (scale) or the salting (e.g. accumulation of anions) of the water because of evaporation in cooling towers. The technologies that were tested at the site are: magnetic separator, 3layer filtration, reverse osmosis and an innovative reactor. Summarizing the results of the field trials and the evaluation it can be conclude that the magnetic separator allows a chemical free and energy saving solid removal in combination with a minimum of 10 times lower sludge amount compared to other technologies connected to lower sludge treatment effort. The blow down recovery by RO is an option for decreasing of waste water discharge and fresh water demand. The 3layerfiltration allows an improvement of sand filter operations at the selected site by using filter sand combinations allowing higher velocities in combination with increased turbidity removal.
Demonstration Sandvik
SANDVIK operates a stainless steel production site in Sandviken, Sweden. Among other products, stainless steel tubes are produced in this production facility. A necessary process step is the pickling of the tubes, which is carried out with a mixture of phosphoric and sulphuric acid. The spent pickling acid is then neutralized and landfilled. Nanofiltration can enable P recovery from P-rich waste streams by allowing the phosphorus to permeate through the membrane and retaining multivalent impurities. During the INSPIREWATER project phosphorus recovery from spent pickling acid using nanofiltration was demonstrated at the Sandvik site in Sweden. The technologies that were tested are: Nanofiltration, microfiltration and reverse osmosis. Summarizing the results of the field trials and the evaluation it can be concluded that the recovery of rinse water is highly efficient for reducing fresh water use, wastewater production and related energy use. The pickling acid recovery system provides a relatively low energy reduction when looking at the factory. An overall efficient solution is to combine the two recovery systems, providing a solution for the RO retentate to be used in the acid recovery system.
Demonstration Clariant
The demonstration case CLARIANT is carried out at the Clariant Ibérica production site in Tarragona, Spain. Here, specialty chemicals are produced, like healthcare products, non-ionic surfactants, additives and cosmetic compounds. A full-scale wastewater treatment plant is part of the infrastructure, where the wastewater of Clariant and neighboring chemical companies is treated. The technologies that were tested are: Forward osmosis with high brihe reverse osmosis or membrane distillation. Summarising the results of the fied trials and the evaluation shows that end-of-pipe water recovery by membrane technologies could be a suitable option, especially in water scarce regions. In particular, the demonstrated concept on the Clariant site in Tarragona exhibits 85% wastewater reduction and direct reuse possibility for medium and low-quality application. 69% fresh water can be saved when deploying full piloted membrane based ZLD concept. Comparing the piloted membrane based ZLD concept with the benchmark ZLD concept using evaporation instead of FO, 31% energy can be saved.
