Verona, ottobre 2013!

Transcription

1 Verona, ottobre 2013!

2 University of Padua Dept. of Chemical Engineering Processes (DPCI) Environmental Systems Analysis Lab(LASA) Eng. Laura Ranzato Comparison between a sensorial technique (Field Inspection) and an atmospheric dispersion model (CALPUFF): odour impact evaluation of an anaerobic digestion plant

3 1. MATERIALS : Outline : how to assess the odourimpact laws and monitoring techniques 2. A CASE STUDY: evaluation of the odour impact of an anaerobic digestion plant with two techniques: odourmonitoring (Field Inspection) odourdispersion dispersion modelling(calpuff) 3. : comparisonbetweenthe techniquesfor odourimpact assessment

4 A CASE STUDY : odour impact assesment with ODOROUS EMISSIONS from PRODUCTION ACTIVITIES citizens complaint NEED TO ASSESS THE ODOUR NUISANCE THE EMISSIONS (at the source) GC/MS + dynamic dilution olfactometry ANALYSIS AT THE RECEPTOR sensorial techniques: Field Inspection/ electronic nose atmospheric dispersion models

5 EVALUATION of the ODOUR NUISANCE The Italian legislation and the European legislation do not regulate the assessment of the odour impact ITALIAN legislation: not any national legislation about odour emissionsand odour impact only regional laws Lombardy Region: o o Guidelines for composting plants, draft: Guidelines for characterization and control of odorous sources ) EUROPEAN legislation (EN : 2003) techniques for measuring odouremissions : dynamic olfactometry techniques for measuring odour impact: none

6 EVALUATION of the ODOUR NUISANCE in many European countries, the legislation evaluates the odour frequency worse than the odour intensity or quality criteria for assessing the impacted area = frequency of exceedance of a threshold UNITED KINGDOM: "IPPC-H4 -Draft. Horizontal guidance for Odour (2002) odour threshold: depending on the hedonic tone (1.5 UO/m 3 ) odour frequency: 98 th percentile of the hourly average concentration GERMANY: Guidelines on Odour in Ambient Air (GOAA, 1998) odour threshold = 1 OU/m 3 odour frequency: depending on the destination of use of the territory

7 EVALUATION of the ODOUR NUISANCE How to estimate frequency ofodours: SENSORIAL TECHNIQUES a) measured by trained people during a referencelaw: VDI 3940 (Germany, 2006) b) measured with an instrument: ELECTRONIC NOSE reference law: none MODELS c) prediction by a MATHEMATICAL MODEL reference law: VDI 3945: gaussian-puff models

8 A case study: odourimpact evaluation of an ANAEROBIC DIGESTION PLANT

9 anaerobic digestion plant in Bassano del Grappa (VI) d

10 vs CALPUFF same GRID Field Inspection grid = 1 x 1.8 km 2, 33 cells with side ~200 m same TIME RANGE 6 months =16 / 7/ 2009 to 15 /1/2010 same ODOUR SOURCES BIOFILTER YARD WASTE BIOGAS BIOFILTER YARD WASTE BIOGAS: cannot be modeled same CRITERIA for assessing the odour impact odour frequency isofrequency lines odour frequency odour threshold

11 CHARACTERIZATION OF THE SOURCES OF ODOURS in the plant area 4 5 PLANT LAYOUT: 1. waste inlet 2. mechanical treat. 3. anaerobic digestion 4. composting plant 5. scrubber + biofilter 6. landfill 90 t/day organic waste 20 t/day yard waste

12 CHARACTERIZATION OF THE SOURCES OF ODOURS most significant sources of odours in the plant area: BIOFILTER treats the exhausted air from the composting process HEAP of YARD WASTE diffuse emissions from yard waste (grass, leaves ) stored outdoor BIOGAS fugitive emissions from anaerobic digestors or from the energy recovery unit

13 CHARACTERIZATION OF THE SOURCES OF ODOURS SAMPLING the odour sources biofilter HOOD (areal sources, emitting with forced flux) heap of waste FLUX CHAMBER (areal sources, with free convection flow) biogas NONE!! (fugitive emission)

14 CHARACTERIZATION OF THE SOURCES OF ODOURS ANALYSING THE SAMPLES GC/MS identify odorous substances OLFACTOMETRY evaluate odor intensity (OU E /Nm 3 )

15 CHARACTERIZATION OF THE SOURCES OF ODOURS ANALYSING THE SAMPLES biofilter 300OU/Nm 3 (*) Nm 3 heaps of green waste OU/m 3 surface= 60 m 2 biogas?? (fugitive emission) 8300 UO/s 5120 UO/s (*) lombardy: Guidelines for composting (Deliberation of Regional Council n 7 / 12764, 2003) BENCHMARK LIMIT VALUE effluent from biofilter 300 UO/Nm 3 ammonia 5 mg / Nm 3 particulate matter 10 mg / Nm 3

16 monitoringprocedure: ODOUR

17 ODOUR statistical method for evaluating the odorous impact regulated by the German VDI No (2006) based on visits within an area of interest around the sources odourassessment is made in some points of interest: the evaluators sniff the air every 10 seconds over a period of 10 minutes, evaluating any odour registration form biofilter, biofilter, none, yard waste Odour Field Inspector 60 MEASURES in 10 minutes

18 ODOUR : settingthe the campaign 16 Odour Field Inspectors recruited between citizens selected for their standard odour sensitivity to the European reference (n-butanol) we trained evaluators to identificate the typical plant odours BIOFILTER odour YARD WASTE odour BIOGAS odour

19 ODOUR : settingthe the campaign monitoring period: at least 6 months (16 july january 2010) every point must be visited at least 26 times, by different panellists, at different hours and days (except for night-time) 26 visitsfor each point of interest * 48 points of interest * 60 measures for each visit 26 * 48 *60 = measures data statistically meaningful!! good estimation of reality!!

20 grid= 1 x 1.8 km ODOUR : settingthe the gridofinterest Field Insp. was carried out on 48 grid points with a mutual distance = 200 m

21 TOTAL PLANT odour frequency in the grid-cells interpolation isofrequency lines

22 modelling procedure: CALPUFF

23 modelling procedure: CALPUFF geophysical data meteorological data STEP 1) diagnostic meteorological model CALMET STEP 2) atmospheric dispersion model CALPUFF emissions data STEP 3) post-processing: plot of isofrequency maps exposure assessment

24 modellingprocedure STEP 1) diagnostic meteorological model SPATIAL GRID computational domain: 5 x 5 km 2 grid resolution : 100 m vertical levels: 20, 100 m

25 modellingprocedure STEP 1) diagnostic meteorological model terrain elevation DEM (from USGS) landuse Corine Land Cover DB

26 modellingprocedure STEP 1) diagnostic meteorological model ground-level data 1 weather station = weatherstation in the plant area sounding data 2 weather stations = Milano airport Udine airport metar data 1 weather station = Venice airport wind speed & direction, T, pressure, Rh at various heights cloud cover & cloud height input for the meteorological model

27 modellingprocedure STEP 2) dispersion model BIOFILTER: 8300 OU/s HEAP of YARD WASTE: 5120 OU/s BIOGAS: cannot be measured cannot be modeled but can be perceived by Field Inspectors

28 vs CALPUFF

29 vs CALPUFF Criteria for assessing the odour impact: GOAA (Guidelines on Odours in Ambient Air, 1998) odour impact occurs when the frequency of odour episodes exceeds the frequency threshold = 10% (municipal areas) 15% (industrial areas)

30 ACTIVE SOURCES ACTIVE SOURCES -biofilter -waste heap -biogas -biofilter -waste heap -biogas: not modelled CALPUFF odour frequency > 15% (orange area) = very frequent episodes of odours [10% 15 %] (yellow are) = less frequent episodes of odours < < 10 %(green area) = odourfrequencyisnotannoying

31 ACTIVE SOURCES ACTIVE SOURCES -biofilter -waste heap -biogas -biofilter -waste heap -biogas: not modelled CALPUFF -the extensionof the odour impact is almost the same (diameter ~ 500 m ) -the odor plume spread more towards the SW (prevailing wind: from NE) -far from the plant:the model overestimatesthe impact MASKING EFFECTS - near the plant: the model underestimates the impact FUGITIVE SOURCE

32 CONCLUSIVE REMARKS the FieldInspectiongivea realisticevaluationofthe odourimpact the resultsofthe techniquesare similar, so the modelassessesthe impactedarea witha good precision especially near the sources so this approach is successful, and it will be used for further investigations the model requires a shorter time and involves less people, compared with Field Inspection. Moreover, the model can be run in a predicitive way Next worksshould study a simplified emission scenario to improve the sensitivity of the analysis

33 Dr. Luca Palmeri ACKNOWLEDGEMENTS University of Padua- Environmental System Analysis Lab (LASA) Main activities: modeling of environmental systems Dr. Maurizio Benzo Osmotech SrL Main activities: odour monitoring

34 Thank you for your attention