Value enhancement of municipal organics through the addition of Effective Microorganisms

Transcription

1 Value enhancement of municipal organics through the addition of Effective Microorganisms Compost Council of Canada Compost Matters! March 11 th, 2015 B A S A N T I B A N D E K A R S U P E R V I S O R D R. G O R D O N P R I C E C O M M I T T E E M E M B E R S D R. A N D R E W H A M M E R M E I S T E R D R. PA U L A R N O L D

2 Introduction Municipal solid waste (MSW): Unwanted waste materials from households and offices disposed off through human activities excluding construction, hazardous and industrial wastes. (Al. Ansari, 2012) Composition of representative MSW Item Percentage (%) Organics (biodegradable) Metals 6-8 Glass 4-8 Plastics 4-6 Other organics Moisture (De Bertoldi et al, 1983)

3 Challenges with MSW Disease vectors Cost of disposing MSW MSW Surface water pollution Ground water pollution Unpleasant odour (Turan et al., 2009)

4 Introduction MSW 2008 Canada Nova Scotia 25.8 million MT 0.3 million MT Non residential Residential Non residential Residential 67% 23% 58% 42% (Statistics Canada, 2008)

5 Definition of composting Composting is an accelerated biological process in which organic materials are decomposed when carbon is oxidized by microbial activity, and the end result is a stable organic product which can be used as soil amendment (Diener et al., 1993)

6 Composting process Raw SSO material (Chen and Inbar, 1993; de Araujo et al., 2010) Photo credits: A. Hammermeister

7 Effective microorganisms A group of mutually compatible species of microorganisms like lactobacteria, yeasts, photosynthetic bacteria, filamentous fungi and actinomycetes. (Xi et al., 2002) Commercial inoculants Dr. Earth, Probio, EM-1 microbial inoculant 1. Lactobacillus plantarum 2. Saccharomyces cereviasiae 3. Rhodopseudomonas plastris 4. Streptomyces griseus

8 Influence of EM on composting process EM inoculation accelerated cellulase activity and organic matter decomposition (Ghaffari et al., 2011). EM addition increases the temperature and microbial population (Xi et al., 2002). No significant difference in accelerating composting process was observed (Daly, 2005). Application of EM had no effect on speeding up the decomposition rate of compost prepared with banana residues (Formorwitz, 2007).

9 Objective Examine whether the inoculation with EM increases rate of carbon mineralization or enhances chemical and physical properties of the mature product(s) from source separated organics (SSO).

10 Specific Objectives Study 1: Evaluation of inoculants to enhance the microbial decomposition in source separated municipal organics from different facilities. Study 2: To evaluate the efficiency of inoculants in a municipal solid waste compost pile.

11 MATERIALS AND METHODS

12 Compost sample collection

13 Maturity criteria and age of compost Facility name Compost maturity criteria Age (months) A No steam from pile and temperature around 20 C. B Cured for minimum of 21 days, respiration rate is 400mg of O 2 /kg of volatile solids/hr, CO 2 evolution rate is 4mg of CO 2 - C/g OM/day, Temp rise of compost above ambient temperature is < 8 C Mature Immature C Temperature stable at 15 C 24 6 D Follow CCME guidelines (category A) and NSDE for compost maturity guidelines 18 N/A E Smells like black earth 24 15

14 SSO maturity assessment (Respirometry) Pre-incubate samples at room temperature 25g compost is added in 45 mason jars & moisture adjusted to 60%. Incubate at 37 C for 5 days Head space extracted everyday (20ml) CO 2 analyzed using a GC (TMECC, 2001)

15 Respirometry CCME, 2005

16 Study 1: SSO Compost Enhancement Study with EM Design of experiment: Factorial design with 2 factors (compost and inoculum): Compost (5 levels). Inoculum - 5 levels (2 commercial EMs Bokashi and Probio, active compost, molasses and plain immature compost). All the treatments are replicated 4 times. Incubated at 37 C for 105 days. CO 2 is sampled every day for first 10 days and five day intervals after. At the end of incubation period, compost physical and chemical parameters will be analyzed and compared to initial compost.

17 Carbon dioxide evolution in Facility A

18 Carbon dioxide evolution in Facility C

19 Study two Compost recipe: A one cubic yard compost pile was built in Bio- Environmental Engineering Centre, AgriTech Park in Bible Hill. Feed stocks: green waste from the cafeteria, Faculty of Agriculture, Dalhousie University as a nitrogen source and barley straw as a carbon source.

20 Study 2: Evaluate the efficiency of inoculants in a source separated organics compost pile Design of experiment: Factorial design with 2 factors (compost and inoculum): Compost (3 stages). Inoculum - 4 levels (2 commercial EMs Bokashi and Probio, active compost, and plain immature compost). All the treatments are replicated 4 times. Incubated at 37 C for 150 days. CO 2 is sampled every day for first 10 days and intervals after. At the end of incubation period, compost physical and chemical parameters will be analyzed and compared to initial compost.

21 Temperature profile of compost pile

22 mg CO2-C/g of C/day Stage one Carbon dioxide evolution Stage Day

23 Stage two Carbon dioxide evolution

24 mg CO2-C/g of C/day Stage three Carbon dioxide evolution 2.0 Stage Day

25 Conclusion The carbon respirometry results for both study 1 and 2 suggest that the carbon dioxide evolution fulfilled the CCME guidelines (<4mg CO 2 -C/ g of OM/day). EM showed significant effect on Facility A and C for study one and stage two for study two.

26 Acknowledgements Committee Members: Dr. Gordon Price Dr. Andrew Hammermeister Dr. Paul Arnold Financial support: Resource Recovery Fund Board Student Grant Program, NS Dept. of Agriculture. Compost facilities across Nova Scotia for their open support in providing materials. Dr. David Burton and Drucie Janes

27 THANK YOU