LCA of plasma-based gas treatment technologies. Inga Stasiulaitiene, Ph. D. Faculty of Chemical Technology Department of Environmental Technology

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1 LCA of plasma-based gas treatment technologies Inga Stasiulaitiene, Ph. D. Faculty of Chemical Technology Department of Environmental Technology

2 APPLICATIONS OF PLASMA FOR THE ENVIRONMENTAL TECHNOLOGIES Characterized as a very reactive media, thus capable in destroying various forms of hazardous substances. Has been demonstrated for variety of applications - Energy sector flue gas treatment - Ventilation exhaust/intake/indoor air treatment - Drinking water decontamination - Wastewater treatment - Environmental spill management - Thermal disposal of solid waste - Decontamination of polluted soils - Synthesis for nano-sized materials for catalysis Etc.

3 ENVIRONMENTAL BENEFITS? Although technologically sound and rather efficient, still struggling their way to the market. Among other aspects, the question remains are these technologies environmentally sound? Life cycle analysis (LCA) helps in assessing overall environmental performance of product systems (or technologies)

4 LCA ANALYSIS Life cycle analysis technique considers the entire life cycle of a product or technology: from raw material extraction and acquisition, through energy and material production and manufacturing, to use and end of life treatment and final disposal Product Design and Life Cycle Assessment, 2006

5 LCA ANALYSIS Life Cycle / Eco Efficiency Assessment Goal and scope definition Inventory analysis Eco efficiency: Product system value assessment Applications: Product development and improvement Stategic planning Budgeting Investment analysis Public policy making Marketing Green purchasing Awareness raising Other Impact assessment Interpretation (including quality assurance)

6 THE METHODOLOGY OF THE LCA The analysis was carried out by comparing several standardized units, involving plasma and non-plasma ( conventional end-of-pipe) technologies

7 EBFGT Electron beam flue gas treatment (EBFGT) technology is a dry-scrubbing process of simultaneous SO 2 and NO x removal, where irradiation of stack gases with an electron beam induce chemical reactions that make removal of SO 2 and NO x easier.

8 WFGD+SCR WFGD with SCR is a two stage NOx/SOx removal process most frequently used to reduce emissions from sulfur-rich coal-fired utility boilers. The WFGD system is usually installed after a baghouse or an electrostatic precipitator. In a typical design, slurry is pumped through banks of spray nozzles to atomize it to fine droplets and uniformly contact the gas. The droplets absorb SO 2 from the flue gas, facilitating the reaction of SO 2 with the reagent in the slurry. SO 2 is dissolved in the liquid and calcium sulfite or sulfate are formed. These are removed by dewatering and settling into a thickener.

9 DBD TECHNOLOGY (1) Non-thermal atmospheric pressure plasma allows the creation of active species without generating excessive heat, which is then easy to use and have lower operational costs. In the DBD field, the oxygen molecules split into two atoms of oxygen, i.e. the elemental oxygen radical forms ozone, when the radical oxygen atom reacts with a normal molecule of oxygen.

10 DBD TECHNOLOGY (2) In this study, the plasmanorm process (Airtec competence GmbH, 2008), was chosen as a representative DBD installation.

11 ZEOLITE REGENERATIVE SORPTION This process consists of an adsorber bed where the volatile compounds are adsorbed. After reaching saturation, the contaminants are desorbed, after which the new cycle can proceed again.

12 BIOFILTRATION This method uses microorganisms to oxidize VOCs, consuming them as a nutritional source. In the biofilter, the polluted gas stream is passed upwards through the filter bed, containing biological material, such as compost, tree bark or peat. The filter material serves as a supplier of necessary nutrients. The degradation products include carbon dioxide, sulfate, nitrate, and other oxides.

13 THE METHODOLOGY OF THE LCA Process boundary was established, based only on processes The functional unit was set as 1000 Nm 3 of treated flue gases

14 Fuel incineration Emmisions to air, soil and water Heat Fuel (diesel) Fuel incineration Iron ore mining and melting Transportation Manufacturing: device housing Emmisions to air, soil and water Emmisions to air Emmisions to air, soil and water Fuel incineration Emmisions to air, soil and water 1 4

15 THE METHODOLOGY OF LCA Inventory analysis of SOx/NOx Parameter Flue gas treatment method EBFGT WFGD+SCR Flue gas flow volume Nm Input Pollutants SO 2 kg 1.17 NO x kg 0.52 Output Pollutants SO 2 kg NO x kg Removal efficiency SO 2 % NO x % Resources kwh Ammonia kg Limestone kg 1.79 Water kg Catalyst (zeolite) kg 0.02 Byproducts Ammonia salts kg 2.01 Wastewater kg 1.03 Water vapour kg 6.15 Gypsum kg 3.09 Catalyst (zeolite) kg 0.02 Stasiulaitiene, Inga; Martuzevicius, Dainius; Abromaitis, Vytautas; Tichonovas, Martynas; Baltrusaitis, Jonas; Brandenburg, Ronny; Pawelec, Andrzej; Schwock, Alexander. Comparative life cycle assessment of plasma-based and traditional exhaust gas treatment technologies.//journal of Cleaner Production. doi: /j.jclepro

16 THE METHODOLOGY OF LCA Inventory analysis of VOC Method Parameter Regenerative adsorption DBD (zeolite rotor) Biofilter Flue gas flow volume Nm Input pollutants Aliphatic hydrocarbons Kg 0.3 Output pollutants Aliphatic hydrocarbons Kg Removal efficiency VOC % Resources Natural gas Kg 0.27 Compressed air m kwh Hydrosorp material Kg Activated carbon material Kg Zeolite Kg 0.37 Water Kg 20 Biofilter (leaf compost, wood chips) m Resources for DBD equipment generation kwh Copper Kg Plastic Kg Printed wire board m Solder Kg Steel Kg Byproducts Hydrosorb material Kg Activated carbon material Kg CO 2 Kg Water vapor Kg Wastewater Kg 0.8 Zeolite Kg 0.37 Biofilter (leaf compost, wood chips) m

17 Gabi 4 professional software with EcoInvent database was used to analyze material flows and to assess environmental impacts. The impacts were presented as global warming potential, acidiphication, eutrophication, human toxicity potential, ozone layer depletion potential. LCA ENVIRONMENTAL IMPACT ASSESSMENT

18 LCA ENVIRONMENTAL IMPACT ASSESSMENT (SOX/NOX) Global Warming Potential Ozone Layer Depletion Potential Materials By-products 7.0E E x10-7 Materials By-products E-07 kg CO2 Equiv kg R11-Equiv. 4.0E E E x E EBFGT WFGD+SCR 0.0E+00 EBFGT WFGD+SCR Acidification potential Eutrophication Potential Materials By-products Materials By-products kg SO2-Equiv kg Phosphate-Equiv EBFGT WFGD+SCR 0.00 EBFGT WFGD+SCR

19 LCA ENVIRONMENTAL IMPACT ASSESSMENT (SOX/NOX) Human Toxicity Potential Overal weighed impact kg DCB-Equiv Materials By-products CML2001 Experts IKP (Central Europe) score Materials By-products EBFGT WFGD+SCR 0.0 EBFGT WFGD+SCR

20 LCA ENVIRONMENTAL IMPACT ASSESSMENT (VOC) Global Warming Potential Ozone Layer Depletion Potential Materials By-products E E-07 Materials By-products 2.93x E kg CO2 Equiv. 1.5 kg R11-Equiv. 2.0E E E E x x Plasma Adsorption Biofiltration 0.0E+00 Plasma Adsorption Biofiltration Acidification potential Eutrophication Potential Materials By-products 1.13x E E-02 Materials By-products 7.19x E-02 kg SO2-Equiv kg Phosphate-Equiv. 5.0E E E x E x10-4 Plasma Adsorption Biofiltration 1.0E E x x10-3 Plasma Adsorption Biofiltration

21 LCA ENVIRONMENTAL IMPACT ASSESSMENT (VOC) Human Toxicity Potential Total weighed impact kg DCB-Equiv Materials By-products Plasma Adsorption Biofiltration CML2001 Experts IKP (Central Europe) score Materials By-products Plasma Adsorption Biofiltration

22 CONCLUSIONS (1) The life cycle analysis proved to be a suitable tool for the assessment of environmental performance of plasma and non-plasma end-of pipe technologies, although certain limitations exist.

23 CONCLUSIONS (2) In case of SOx/NOx treatment, EBFGT performed better compared to WFGD+SCR with respect to acidfication, eutrophication, and human toxicity potential due to the possible utilization of by-products; on the other hand, due to higher energy consumption, it was worse with respect to global warming potential and ozone layer depletion. In case of VOC treatment, DBD-based plasma unit successfully competed with zeolite adsorption and biofiltration unit. The energy consumption was not a major contributor, but the management of remaining waste caused the highest impact to the environment.

24 REMOVAL OF POLLUTANTS BY ENHANCED PLASMA/CATALYSIS/SORPTION/REGENERATION TECHNOLOGY

25 FURTHER INFORMATION Full report available at: downloads Reports, surveys and other results of PlasTEP. Stasiulaitiene et al., Comparative life cycle assessment of plasma-based and traditional exhaust gas treatment technologies, Journal of Cleaner Production, doi: /j.clepro Contact