important elements for successful biogas projects€¦ · water recycle, use as process water, wash...
TRANSCRIPT
Important Elements for successful biogasprojects
Steve Brewster
1Webinar - May 2015
IDENTIFY DRIVERSEnergy extractionRegulatory complianceLandfill MinimisationGreen House Gas controlEnvironmental
2
Parameter Design BVFInfluent
Removalefficiency
Flow (m3/d) 2 990
COD (mg/l) 25 000 99%
BOD (mg/l) 12 500 99.6%
TSS (mg/l) 2 200 96%
TN (mg/l) 200
IDENTIFY PRODUCT PRIORITIESBiogas use it, sell it, upgrade itFertilizer use it, sell it,Biomass dry it, sell for fertilizer – when dried it stores well,
packs well, light & transportableWater recycle, use as process water, wash water, further
purification to potable water
4
Know your feedstock• Feed characteristics determine plant process and design• Volumes -Max and min• Seasonality - e.g. Dairy, fruit waste, vineyards• Variability - Many samples over time• Analysis - water content, BOD, pH, consistency, temperature• Inhibitory Factors - Disinfectants, antibiotics
- Biological = pathogens, viruses• Contamination - glass, plastic, wood, metal, sand & rocks• Consider multiple feedstocks and sources - Source and feed
- diversity is good• Contract - Don’t accept supplier’s word on content, do due
diligence on the supply and material 5
Agricultural & Horticultural
Food and Beverage
Dairy
Breweries & Distilleries
Fisheries & Abattoirs
Pharmaceutical and Chemical
Pulp and Paper & other industries
Municipal sorted wastes
PossibleFeedSources
SECURE YOUR FEEDSTOCK !Ensure the feed will be available as plannedContract it if possible to ensure it continues to match plant designMultiple feeds and sources ensures stability of operation.Set-up an analysis programme the feedstock suppliers need to complywith and document, to ensure the quality of the feed
Plant success depends on the feedstock
7
8
Sydney
DEFINE THE PROCESS
9
Produce a Process & Instrumentationdiagram and.
10
11
A scaled equipment layout plan as the basis for most ofthe subsequent detailed civil, electrical and hydraulicdesign
CONSIDER DOWNSTREAM PRODUCTSHeat - Direct flame, boiler ,dryer, steamElectricity – IC engine, micro-turbine, sterling engineClean water - Digestate requires further treatment and solids and dissolved
components removed by membrane, RO etcCooling (directly or indirectly, absorption chilling or electric compression)CNG (for pipeline reticulation or transport fuel)
Other chemicals from biogas refining and reforming, plastics etcCarbon Dioxide - dry ice, drink aeration, greenhouse atmosphere
CO2 enrichment
12
CNG powered bussesBiogas fuelledBoiler
MONITOR YOUR PRODUCTS
Regular analysis of products (digestate & Biogas)
Document it to have a proof of quality
13
BIOGAS TREATMENTUpgrading:
Scrubbing (H2S, SiOx, CO2, H2O) removalTransport
Compressedto CNG in steel tanks for vehiclesMeasurement
Rated by energy content; measure % methane
15
Biogas Treatment and Utilisation
16Refuelling of an institute vehicle with biogas from the farm biogas digester around 1986. Invermay,Dunedin
NZ history
Hidden & forgotten considerations
17
• Environmental - Resource consents & appeals= costs & delays
- Does intended use match the permitted orspecified use?
• Hazardous area survey - electrical requirement
• Gas regulations - Aus; state to state differences, Consider Porkindustry code of practise.
• Electrical supply - Adequate for load? consider distance tomajor loads
• Water supplies - Quantity, Potable and process (recycled) water
• Site waste disposal, traffic volumes and control, noise, odours, dischargesto air / water / soil, operational hours
• Benefits from larger scale operations
CONTRACT
Possible contract services:Design,Design-build,Design build operate,After project completion servicesFinancial model, payment timing, cash flow
18
CONTRACTSInternational considerations,
local regs and laws regarding ownership & operations.Local custom,local labour“Inducements”
InsurancesWarranties
19
CONTRACTORSModel: Project manager or master contractor?Who provides what;Health and safety; who?Demarcation of responsibilitiesElectrical - competency, familiarity with gas sitesConstruction contractor. Competency, communications,
cooperation with other trades, leadership
20
Parameter Design BVFInfluent
BVF Effluentquality
Flow (m3/d) 8 000
COD (mg/l) 8 000 < 300
BOD (mg/l) 2 800
TSS (mg/l) 2 700 50-500
TKN (mg/l) 81
COMPONENTSInstruments - single vendor
Equipment / process Packages – clearly defined responsibility,- diagram. Confirm interface
requirementsMechanical Equipment - define installation demarcation
points and responsibilities.
22
SUPPLY LOGISTICSGetting stuff from wherever to the project site in timely fashion:
Transportation methodStorage & insuranceClimatic considerationsCash flowWarranty time-outs Timing of orders and site arrival
23
Digester types
24
Standard tank design
– Small footprint– Accessible
– More expensive– Parts usually remotely manufactured– Considerable civil design & work required
In – ground– Inexpensive– Simple to construct– Mostly local materials & labour– Liner & cover – imported– Requires large area
25
Digester types
NZ expertise history
Duffill Watts & King
26
The first full-scale plantundertaken by the companyforbear in 1991. The formerFortex meatworks (Dunedin,New Zealand)
In-Ground casava waste treatment. Approx 8 Megawatts combined Electricity and heat output
ADI-BVF®- Dairy Plant Application
Flow(m3/d)
COD(mg/l)
Biogas(m3/d)
CH4(%)
BVF(ML)
Additionaltreatment
450 6800 1400 75% 5.6 SBR
28
ADI-BVF®- Dairy Plant Application
Flow(m3/d)
COD(mg/l)
Biogas(m3/d)
CH4(%)
BVF(ML)
Additionaltreatment
4000 6520 10900 75% 28 SBR
29
ADI-BVF®- Dairy Plant Application
Flow(m3/d)
COD(mg/l)
Biogas(m3/d)
CH4(%)
BVF(ML)
Additionaltreatment
1860 25,000 28,800 75% 39.3 SBR
30