Biogas Utilization for Low Production Landfills. W. Gregory Vogt SCS Engineers 7 November 2006, Rimini

Transcription

1 Biogas Utilization for Low Production Landfills W. Gregory Vogt SCS Engineers 7 November 2006, Rimini 1

2 Outline Introduction Two East Coast USA case studies for heating small buildings Microturbine examples Conclusions 2

3 Onsite Energy Needs Electric Power Consumption Pumps Blowers Leachate Treatment Buildings - Lighting, Ventilation, etc Other Equipment - e.g., Shredders 3

4 Onsite Energy Needs (continued) Oil and Gas Heating Leachate Treatment Auxiliary Fuel for Incinerators or burners (e.g. wood waste) 4

5 Landfill Facilities Ripe for Retail Deferral Landfill gas flare station (50 hp blower 7.5 /kwh) Leachate or groundwater treatment plant MRF or transfer station Office complex Onsite Incinerator Over the Fence User 5

6 Introduction Technologies for landfill gas usage Conventional: boiler, electricity generation, pipeline upgrades Emerging technologies: Vehicle fuel, micro turbine, fuel cells, greenhouses... Infrared radiant tube heaters - 1st in US 6

7 Principle of Operation Infrared radiant tube heaters Same principle as the sun Heats the floor and objects 7

8 Landfill 1 Opened 1993, closure planned: ha facility; 45 ha for landfilling 1.5 million tons of waste in place Receives 550 tons/day of waste 3 ha portion capped (1999) 850 m3/hour* * 500 cfm 8

9 Frederick County Landfill, VA LFG PIPELINE CDD CAPPED AREA PERMIT 529 SCALE HOUSE PERMIT 40 BLOWER/FLARE MAINTENANCE SHOPS N APPROXIMATE SCALE 9

10 Feasibility Study Analyzed various alternatives $12K-15K/yr. 15K/yr. propane cost Recommended New infrared heaters Parallel with existing system Payback between 5 and 10 years 10

11 T T Biogas Service Line, Landfill 1 STORAGE BUILDING BLOWER/FLARE SKID COMPRESSOR BUILDING MAINTENANCE BUILDING NEW 4"Ø HDPE, SDR 17 LFG SERVICE LINE SCALE IN FEET 11

12 Blower/Flare Area, Landfill 1 12

13 Maintenance Building, Landfill 1 LFG SERVICE ENTRANCE FOR MAINTENANCE BUILDING FROM BLOWER/FLARE STATION T HTR3 HTR1 GARAGE DOOR T LEGEND WALL VENT NEW HEATER ROOF VENT EXISTING PROPANE HEATER NEW LFG HEATER T THERMOSTAT AND EMERGENCY SHUT-OFF ABOVEGROUND LFG PIPE VENT DUCT HTR2 T HTR5 T OFFICE SPACE HTR6 HTR4 T SCALE IN FEET 13

14 Maintenance Building, Landfill 1 14

15 Maintenance Building, Landfill 1 15

16 16

17 Storage Building, Landfill 1 T GARAGE DOOR HTR9 LEGEND T HEATER WALL VENT LFG HEATER THERMOSTAT AND EMERGENCY SHUT-OFF VENT DUCT ABOVEGROUND GAS PIPE HTR8 DOOR T GARAGE DOOR EXISTING PANEL "LP" HTR7 OFFICE SPACE T FROM BLOWER/ FLARE STATION LFG SERVICE ENTRANCE FOR STORAGE BUILDING SCALE IN FEET 17

18 Landfill 2 Closed, mid s 130 ha landfilled,, 22 million tons 65 ha portion capped 300 collection devices 18

19 I-95 Landfill ~Waste Footprint SCALE HOUSE MAINTENANCE SHOP I-95 Occoquan MAINTENANCE SHOPS 19

20 Maintenance Building, Landfill 2 20

21 Maintenance Building, Landfill 2 21

22 Design/Construction/Operation Landfill 1: 50 m3/hr Landfill 2: 25 m3/hr Stainless steel above- grade, HDPE below grade Standards heaters - modified for LFG Simple controls Ordinary mechanical contractor Construction time - 3 months Simple to operate Minimal maintenance expected 22

23 Startup/Operation Landfill 1 startup in late 2001 Operated for a few weeks Problem with sensor fouling Fixed by filtering out siloxane Carbon-filled drums Operational since December

24 Activated Carbon System 24

25 Findings First LFG infrared heater projects in the US Reasonable payback About 50 m3/hour biogas needed to heat about 600 m2 Minimal gas treatment Low sophistication - simple to operate 25

26 Microturbines Available from Capstone and Ingersoll- Rand in 30, 70 and 250 kw sizes NO x emissions one-tenth of reciprocating engines High pressure fuel (80 to 90 psig) Operates at 30% to 35% methane Net heat rate of 13,900 Btu/kWh to 15,400 Btu/kWh (HHV) 26

27 Microturbine Installation, San Diego 27

28 Microturbines (continued) Can recover hot water Equipment cost = $1,000 to $1,200/kW Installed cost = $2,200 to $3,500/kW Maintenance cost = $0.01 to $0.015/kWh Reasonable amount of field experience 28

29 Gas Treatment Skid for Microturbines 29

30 Calabasas Landfill Ten Capstone 30 kw microturbines 300 kw (gross) / 250 kw (net) Microturbine inlet pressure = 80 psig 30% to 45% methane content H 2 S = 75 ppb; siloxanes = 700 ppb 80 psig sliding vane compressor / chilling of gas to 40º F / reheat of gas by 20º F / activated carbon on 100% of fuel 30

31 Calabasas Landfill Capital cost = $770,000 ($2,570/kW) O&M cost = 2.5 /kwh Onsite retail deferral at 15 /kwh Interconnection cost = $5,000 ($16/kW) Design/construction = 5 months Simple payback (after grants) = 1.6 years 31

32 Conclusions Rising energy costs can make smaller projects viable Several emerging technologies are available to support small LFGTE projects Microturbines are proven technology (>25 USA projects in operation, startup, or design) 32

33 THANK YOU! 33