Composting Toilet Guidelines and other Initiatives. Composting Toilet Initiative

Transcription

1 Composting Toilet Guidelines and other Initiatives Rupert Benzon Ministry of Health Health Protection Branch Composting Toilet Initiative Concerns raised by stakeholders that option needed for low flow systems Approval to move forward with composting initiative granted by Ministry of Health in late 2014 Composting Toilets to be an option for onsite (filing with Health Authority) 1

2 Outcomes of Composting Toilet and greywater system Guidelines Enhanced understanding of composting toilets as an onsite alternative Designs and installations suitable to site specific conditions System designs which protect public health and the environment Developments based on reduced water consumption footprint Outcome based criteria for compost material and grey water quality. Support of composting toilet applications through health authority filing process Other Initiatives Review of Maintenance Bylaws as Tools for Onsite Management Review what is being done across Canada Develop principles or common elements Goal to promote local government s authority and potential role in maintenance Ground Water at Risk of Pathogens document Provides a framework for determining risk to drinking water supplies and disinfection requirements Document and consultation process available at: 2

3 Recap of Accomplishments Version 3 Standard Practice Manual Training on SPM V3 Thank you! Rupert Benzon Land Use Manager Rupert.Benzon@gov.bc.ca (250) Michele Gee Drinking Water/Wastewater Engineer Michele.Gee@gov.bc.ca (250) Mike Zemanek Director Healthy Community Environments Michael.Zemanek@gov.bc.ca (250)

4 Composting toilet and greywater practice WCOWMA Workshop 2015 Introductions Ian Ralston ROWP Eng.L Ed Hoeppner ROWP 4

5 Context and draft process Manual of Composting Toilet and Greywater Practice (MCTGP) Early draft ASTTBC for Ministry of Health Ian Ralston, TRAX Timeline Consultation 9 Technical group Gord and Ann Baird Geoff Hill Ed Hoeppner Michael Payne Mike Seymour 10 5

6 Purpose of the Manual Standards and guidelines Filing approach For: Non water borne waste management Greywater systems Seasonal diversion systems Source separation systems 11 Manual approach Based on SPM, does not repeat SPM Split to standards and guidelines Separate rationale Performance objectives Appendices 12 6

7 Basis for standards Same approach as SPM Outcome (performance objectives) Rationale Where practical, builds on SPM standards Allow opportunity for innovation 13 Filing under the SSR Composting toilet systems On site burial of composting toilet residual organic matter Greywater systems Seasonal diversion systems for greywater sub surface irrigation 14 7

8 Under the OMRR Land application Possibly with simplified process 15 BC Building Code WC required by BCBC for Part 9 bldgs. Composting toilet as equivalent Generic wording for alternative solution Manual and rationale as support Approval rests with AHJ (local authority) 16 8

9 MCTGP SOURCE SEPARATED WASTE SYSTEMS Typical sanitary drainage and sewerage systems Water closets for human waste Plumbing fixtures Combined sanitary drainage system To onsite sewerage system No intentional recycling of resources 18 9

10 Ecosan 19 Source separation Water closets for human waste Blackwater Plumbing fixtures Greywater Separate sanitary drainage system To onsite separate sewerage systems Intentional recycling of some resources 20 10

11 Composting toilets Composting toilets for human wastes Plumbing fixtures Greywater Greywater onsite sewerage system 21 Composting toilet option Non water borne system: Collection Conveyance Treatment (composting) Discharge 22 11

12 Other separation options for human waste Water borne sanitary drainage with: Separation of feces and TP by filter Or by centrifugal action (Aquatron) Ultra low flush toilets Vacuum toilets and collection 23 Source separation options Urine Brownwater Types of greywater: Very Light Greywater Laundry Greywater Light Greywater Dark Greywater Seasonal greywater diversion 24 12

13 MCTGP PURPOSES Why use a composting toilet? Constraints for conventional system Water conservation Reduced volume for solid waste removal Recycling of organic matter and nutrients Life style choice 26 13

14 Why use a greywater system? Smaller sewerage system Irrigation to use water and nutrients Water conservation in summer Flexible seasonal options Life style choice 27 Why use source separation? Treatment and discharge designed for specific waste or wastewater type Reuse of nutrients from urine Reuse of water for irrigation 28 14

15 MCTGP COMPOSTING TOILETS Primary purposes Safely collect and contain human waste Manage odors and prevent vector or human access during storage Manage leachate and safely discharge leachate or diverted Provide for safe and practical management of residual organic matter

16 Secondary objectives (e.g.) Volume or mass reduction Stabilization for transport Stabilization and sanitizing for: On site burial On site land application 31 A composting toilet system Toilet pedestal Collection and conveyance system Composting processor 32 16

17 Pedestal and inputs 33 Collection or conveyance Direct to processor To bucket or bin To dedicated bin processor Ultra low flush, or foam toilets Water borne with filtration or Aquatron Diversion of urine (improves process) 34 17

18 Aquatron separator 35 Compost filter 36 18

19 Types of composting processor Batch Continuous 37 Composting 38 19

20 Batch bins Milkwood 39 Batch bins Milkwood 40 20

21 Aquatron batch carousel 41 Inclined floor continuous processor Clivus Multrum 42 21

22 Foam flush toilet Water and soap 0.18 L water per flush No water trap (vent fan used) 43 Continuous mouldering decomposition process Clivus Multrum 44 22

23 The composting process Aerobic Moist Warm May use worms or BSF larvae Often with additives E.g. bulking agents 45 Stabilization and sanitizing Stability Maturity Pathogen removal 46 23

24 Stages (typical batch) Collection and addition Mesophilic phase Thermophilic phase Mesophilic cooling phase Curing phase 47 Stages of composting 48 24

25 Other potential phases Pre-treatment Microaerobic fermentation Pasteurization Drying toilet collection Continuous mouldering process May be followed by batch process Incineration 49 Residual organic matter Off site discharge On site discharge Burial Land application 50 25

26 On site discharge Process standards Documentation of process Testing of residual organic matter Burial standards (under SSR) Land application, professional, OMRR

27 Batch sanitizing step Process standards Documentation of process Testing of residual organic matter Burial standards (under SSR) Land application, professional, OMRR

28 Batch curing or sanitizing steps 55 Outcome based standards With documentation and testing 56 28

29 MCTGP ON SITE BURIAL OF RESIDUAL ORGANIC MATTER Process standards Incineration Curing Stabilizes Long term curing = sanitizing Specific sanitizing steps Still required stability (curing) May reduce required curing time 58 29

30 Batch sanitizing steps Thermophilic step Pasteurization ph adjustment Urea addition 59 Process monitoring Documented monitoring Review by AP 60 30

31 Material testing Stability and maturity testing Quality standards By AP or under AP supervision 61 Burial, follows SPM standards Site and soil evaluation Vertical Separation and other standards per gravity standards Cover standard and no disturbance Loading rates Based on SPM Adjusted by factor 62 31

32 MCTGP GREYWATER SYSTEMS Source separated wastewater Urine Composting toilet leachate Blackwater and brownwater Water separated from blackwater Greywater 64 32

33 Urine Low pathogen content Most of the nitrogen High phosphorous A person s urine will fertilize approx. 80% of crop intake 65 Composting toilet leachate High strength (BOD close to sewage) Pathogens similar to septic tank effluent High NH 3 and salts Low volumes Some composting systems retain Combine with greywater or dark greywater 66 33

34 Types of greywater Dark grey = Kitchen Light grey = all but Kitchen Very light grey = Bath, shower, hand basins Laundry Total greywater: High P content (~50% of total WW) BOD ~50 60% of total Flow ~60% of total 67 Type Average flow (L/c/dy) BOD (mg/l) Fecal Coliforms Log10CFU/100mL Light Grey to 5 Dark Grey to 7.6 Blackwater Sewage to 7 Septic tank effluent to

35 Types of greywater system All season Seasonal diversion Urine diversion Urine storage for seasonal use 69 MCTGP URINE DIVERSION AND STORAGE 70 35

36 Urine diversion Waterless urinals Urine diverting toilets Urine diversion in CT pedestal Urine separation in CT conveyance 71 Waterless urinals New or retrofit Trap with oil Curtain valve 72 36

37 Maintenance issues with liquid traps Each urinal has two plastic insert pipes, which are removed to replace the blue blocking liquid (this liquid just drains to the sewer) 30 August 2006 in UNESCO-IHE building after approx. 5 months of use 73 Low cost waterless urinal for South Africa and beyond Urinal bowl viewed from underneath (minimal maintenance required) Supplier: Addicom, see detailed info on next 3 slides Price: approx. $100 Addicom EcoSmellStop device (ESS) 74 37

38 75 Ernst waterless urinal (at a camping park in Switzerland) This painted-on fly improves men s aiming (don t laugh, it s true!) Same EcoSmellStop device as Addicom (previous slide) 76 38

39 Advantages and disadvantages of rubber tube/curtain vs. oil based odour control systems Advantages: Quick and easy to clean Does not need frequent and costly replacement of blocking fluid Can be inspected without losing blocking fluid Much less likely to develop hard blockages Disadvantages: May need regular manual cleaning Rubber tube may loose elasticity over time and need replacement (but low cost) 77 Urine diverting toilet 78 39

40 Urine diverting seat for composting toilet pedestal 79 Urine storage ~ sterile with 6 months at 20 C Store and fertigate Dilute 1 urine : 10 water or greywater Or urine can just be combined with the all season greywater system 80 40

41 Urine fertigation Subsurface To diversion system mulch basins To other seasonal sub irrigation system Standards provided 81 MCTGP GREYWATER SYSTEM STANDARDS 82 41

42 Adjusted standards Adjust SPM standard by multiplier DDF Septic tank size HLRs 83 DDF adjustment 84 42

43 Septic tank size

44 All season greywater systems Meet all standards of SPM Use adjusted design inputs Allows use of mulch cover for chambers 87 Adapting dispersal systems Subsurface Drip Dispersal for irrigation Sand lined beds Bottomless sand filters as planter beds Shallow or at grade chamber systems Mulch cover standard 88 44

45 Irrigation demand growing season only Diversion systems Zoned systems Water addition in summer Forest irrigation in winter Aquifer recharge Nutrient benefit Nutrient risk also 89 Seasonal diversion Light greywater only Small, residential only Most standards per SPM Summer season VS, no summer LLR Must have alternate discharge Sewer Onsite system Direct subsurface discharge Mulch basins and branched drains 90 45

46 Diversion of light greywater Y valve Sliding gate valves Backflow risk management Labeling Divert during rainfall events

47 MCTGP TECHNIQUES FOR SUB IRRIGATION 93 Mulch basins and branched drains Gravity dispersal, splitting flows using splitter tees To shallow basins with mulch Can use chambers for the basins Maintenance (including cleaning chambers and replacing mulch) will be needed 94 47

48 Oasis branched drain 95 Oasis branched drain 96 48

49 Splitter 97 Branched drain and mulch 98 49

50 Tipping D-Box Mulch basin with chambers, low HLR 99 Sub irrigation mulch basin To sand media or soil with chambers All systems Basin, trench or bed Consider risk from rainfall input Direct discharge OK for seasonal diversion To mulch media with chambers or other enclosures Small flow residential seasonal diversion only Direct discharge OK Partial treatment in mulch

51 Mulch basin layout Allison Bailes m/blog-building-science-hers- BPI/bid/38249/How-to-Install- a-branched-drain-greywater- System-in-a-Green-Home 101 Branched drains to all season system

52 Discharge to soil with blinding layer

53 Chambers under mulch only. All season system

54 107 Clivus Multrum greywater illustration, chamber system

55 Mulch infiltrative surface (small flow residential seasonal diversion only) Mulch standard Based on performance Similar to sand mound loading High HLR to mulch Minimum mulch depth Basal area HLR 109 Small mulch basins with mulch infiltrative surface

56 Dosed mulch basin. 111 Subsurface drip dispersal Good option for subirrigation where using combined wastewater stream Flexible, easy application to varying zones Meet SPM standards Not for direct application, Type 1 pretreatment at minimum

57 Subsurface drip dispersalfurther cautions Use tubing and components designed for Wastewater and for subsurface use Essential to maintain unsaturated conditions 113 URS New Zealand Employee Presentation p

58 Installing around greens in stage 2 Employee Presentation p 115 Tee installed in 1 day (URS) Employee Presentation p

59 Long term Irrigated vs. Non-Irrigated URS Planter bed systems Adaptation of bottomless sand filter Meet SPM standards Not for direct application, Type 1 pretreatment at minimum Design for irrigation and fertigation objectives

60 Precast Planters Combined Wastewater Treatment 119 Cast in Place Planter Combined Greywater Treatment

61 Seasonal Evapotranspiration Not in Manual so far Design recognizing ET for seasonal diversion systems Or for summer use only sites Or with pump and haul in winter 121 Questions? Ian Ralston Eng.L Ed Hoeppner ROWP