Biogas upgrading, compression and utilization as an alternative to CHP Dr. Alfons Schulte-Schulze Berndt April,
1 Company, Technology and Products 2 Biogas production and utilization routes 3 4 4 Quality & specification Biogas, CNG and LNG Biogas upgrading process / Standard & Advanced technology Utilization alternatives / Best practice examples in Europe
Company Viessmann Group HQ Germany Heat & Power supply systems from 1.5 kw to > 120 MW Oil, Gas, Solar, Photovoltaic, Biomass, Biogas
Company Carbotech Company and Products Experts in Gas Processing & Biogas Upgrading
Carbotech Products and Services Turn- Key On - Site Gas Generation and Purification Biogas Biogas/LFG/Sewage upgrading to pipeline quality and grid injection units & Bio-CNG / Bio-LNG, small to large scale containerized upgrading and injection plants Hydrogen Nitrogen on-site hydrogen purification and generation small to large scale customized PSA- units small hydrogen generators utilizing SMR NEW: PEM water electrolysis on-site nitrogen generators small scale standardized to large scale customized ProcessGas process gas purification customized small scale to large scale, Coke Oven Gas purification References > 1000 PSA systems installed worldwide since 1989, capacity up to 20.000 Sm/h
Biogas Upgrading and Utilization Biogas utilization and alternatives Bio-CNG and Bio-LNG Conventional Direct Power Production Conversion to CNG or LNG or Grid Injection Biogas Upgrading Biomass Biomethane Slurry Anaerobic Digester Biogas Power Grid Off-gas Trailor transport Power Heat CHP On site CHP Power Heat CNG LNG CHP Natural Gas Grid Grid Injection Disadvantages: Advantages: High CHP maintenance cost Low CHP-Efficiency Best remote area concept No CHP investment High CHP-re-invest Limited grid access No power grid limits Highest sustainability Low overall profitability Low FIT for power Highest added value High overall profitablity
PSA Biogas Upgrading Process Biogas quality at Digester outlet Parameter Air Biogas @ Digester Outlet Methane 50 60 % Carbon dioxide 40-50 % H2S Scrubber Nitrogen < 1 % Oxygen < 0,2 % Wash fluid Water 3000 6000 mg/sm3 Hydrogen sulfide 2000 to 4000 ppm* (EFB) Cooling& Condensing Secondary Digester / Gas Storage Biogas PSA towers Biogas Plant Digester Bio-Methane POME & EFB Hydrogen NH3 Compression 500 ppm up to 100 ppm Caloric Value (HHV) Siloxane 16 22 MJ/Sm3 5 20 mg/sm3 H2S Fine Cleaning Off Gas Other CxHy < 100 ppm
PSA Biogas Upgrading Process Biogas quality at H2S Scrubber outlet Air H2S Scrubber Secondary Digester / Gas Storage Biogas Plant Digester POME & EFB Biogas Wash fluid Biogas Parameter Compression Biogas @ H2S Scrubber Outlet Cooling& Condensing Methane 46 56 % Carbon dioxide 36-46 % Parameter Hydrogen NH3 PSA towers Biogas @ H2S Scrubber Outlet 500 ppm < 10 pm Bio-Methane Nitrogen up to 6 % Oxygen up to 2 % Water 3000 6000 mg/sm3 Hydrogen sulfide 200 to 400 ppm H2S Fine Cleaning Caloric Value Siloxane Other CxHy Effect of H2S - scrubber air injection 15 20 MJ/Sm3 5-20 mg/sm3 < 100 mg/sm3 Off Gas
Gas quality specification Biogas / CNG / LNG Gas specifications & quality requirements Bio-CNG & Bio-LNG Parameter Raw Biogas @ Upgrading Plant Bio - CNG to meet ISO/SAE CNG stand. Bio-LNG to meet Int. LNG stand. Methane 46 56 % > 95 > 98 % Carbon dioxide 36-46 % 1-3 % < 50 ppm Nitrogen up to 6 % 1-2 % < 1 % Oxygen up to 2 % < 0.5 % < 0.1 % Water 3000 6000 mg/sm3 < 50 mg/sm3 < 10 mg/sm3 Hydrogen sulfide 200-400 ppm < 3 ppm < 3 ppm Hydrogen 500 ppm < 1000 ppm < 1000 ppm NH3 < 10 ppm technical free technical free Caloric Value (HHV) 15 20 MJ/Sm3 37-42 MJ/Sm3 38 46 MJ/Sm3 Siloxane 5 20 mg/sm3 < 5 mg/sm3 < 1mg/Sm3 Other CxHy < 100 ppm no condensation @ 250 bar No condensation @ 10 bar / -170 C To meet quality standards and caloric value these steps are a must : CO2 and significant air rejection (N2 & O2 ) Total H2S removal Very high gas drying Siloxane and CxHy removal Total CO2 removal required only for LNG
Gas quality specification Biogas / CNG / LNG Biogas upgrading challenge Challenge for the advanced biogas upgrading system : is not to remove CO2, (any Water or Chemical Scrubber or any Membrane can do this job) but within same plant simultaneously also reject significantly part of air (N2 & O2 ) remove totally H2S provide very dry gas remove Siloxane and other condensable CxHy Only Carbotech PSA biogas upgrading units can ensure this :
PSA Biogas Upgrading Process Overall process assembly Biogas Plant Air H2S Scrubber Secondary Digester / Gas Storage Digester POME & EFB Biogas Wash fluid Biogas Activated Carbon Carbon-Molesieve PSA towers Bio-Methane Compression Cooling & Condensing PSA Biogas Upgrading Plant Condensate H2S & Siloxane Removal Off Gas
PSA Biogas Upgrading Process Process basics Gas molecules: Biomethane CH 4 N 2 / O 2 H 2 O/ H 2 S Power needed kwh el /m³ 0,25 CO 2 0,20 0,15 Carbon Molecular Sieve (CMS) 50 40 30 % CO 2 -Biogas Biogas Compressor Vacuum Pump CH 4 / CO 2 / N 2 / O 2 / H 2 O / H 2 S CO 2 / N 2 / O 2 / H 2 O / H 2 S / CH 4 Main Characteristics: Separation through molecular sieve effect; CMS fully self-regenerated Biomethane production at elevated pressure CMS regeneration at low pressure. Selective & simultaneous separation CO 2, H 2 O, H 2 S, NH 3, N 2 & O 2 Operational pressure range 1 10 bar Upgrading Process at ambient temperatures 5 40 C
PSA Biogas Upgrading Process 3 D Model Waste gas upgrading plant 2000 Nm3/h Product buffer tank H2S & Siloxane adsorber Raw gas buffer compressor dry cooler Control Room Vacuum pump Chilled water unit 6 bed PSA
PSA Biogas Upgrading Standardized Model Range plant type raw gas capacity [Sm 3 /h] (raw gas capacity) [SCFM] container compressors vacuum pumps average power consumption @ 40 % CO2 BUP 350 350 (210) 1x40 1 1 80 kw BUP 500 500 (300) 1x40 2 1 110 kw BUP 750 750 (440) 1x40 2 2 165 kw BUP 1000 1000 (600) 2x40 3 2 220 kw BUP 1200 1200 (710) 2x40 3 3 260 kw BUP 1400 1400 (830) 2x40 3 3 300 kw BUP 2000 2000 (1200) 2x40 4 4 430 kw TaylorMade 3000-5000 (1800-3000) Cont/Skid 4-8 4-8 0.22 kw/sm³
PSA Biogas Upgrading Process Features, benefits & advantages Carbotech PSA single stage removal of CO 2 & H 2 O & NH3 & CxHy, Siloxanes, N 2 /O 2 no post treatment, biomethane is very dry High product quality, up to 99 % CH 4 high methane recovery, up to 99% No dilution of biomethane with O 2 /N 2 dry process, no process water or liquids no chemicals, no waste materials no offgas treatment, offgas free of H 2 S automatic part load adjustment 30 to 110% very power efficient 0,16 to 0,22 KW/m3 No plant performance degradation over time
PSA Biogas Upgrading Process Features & Benefits: Carbotech PSA specials : Air Rejection PSA integrated Air Rejection process no additional separation stage to remove O2 and N2 needed to achieve gas grid & CNG quality flexible Air Rejection can be adjusted without additional hardware-> high availability even with upset inlet gas conditions CH4 recovery / % Unique for PSA not possible for Membrane or scrubber systems 1 0,99 0,98 0,97 0,96 0,95 0,94 Raw Biogas 0,93 @ 0,92 2 4 % Air 0,91 0,9 8 bar s 8 bar ns 2015 8 bar s 2015 0 0,2 0,4 0,6 0,8 1 O2 removal efficiency / %
PSA Biogas Upgrading Process Features & Benefits: PSA specials : CO2 free Biomethane PSA integrated CO2 purifier removal of CO2 from 3 % to < 50 ppm CO2 CO2 free Biomethane mandatory for Bio-LNG production No additional gas losses, maintaining high CH4 recovery No additional compressor, no additional PLC / control system H2S / Siloxane / VOC Removal Regular PSA Biomethane CO2 free Biogas Compression Cooling& Drying CO 2 Purifier Vacuum Pump
PSA Biogas Upgrading Process Features & Benefits: PSA specials : Ageing and Power Consumption Specific power consumption (kwhel/sm3 raw gas) 0,4 0,35 0,3 0,25 0,2 0,15 0,1 Power consumption versus operation time Membrane (10 years average) Membrane (ageing over time) Assumption : - Capacity 1000 Sm3/h - CH4 recovery > 99 % - Biogas < 2mbar @ 35 C - Product max. 3 % CO2 - All auxilliary units included - Power : 0,1 $/Kwh Membrane module change after every 4 to 6 years operation PSA Upgrading Plant (no ageing effect) 1 2 3 4 5 6 7 8 9 10 11 Years in Operation 2 Mio. $ savings PSA versus Membrane PSA plant 10 years operation
PSA Biogas Upgrading Process Alternative Biomethane utilization options Source : Atlas Copco CNG Compressors / Download Brochure
Plant Examples Biogas upgrading plants BUP 350, Sewage Gas BUP 500, Agricultural Waste BUP 750, Slaughterhouse BUP 1000, Municipal Waste BUP 2000, Agricultural Crops BUP 1800, Landfill Gas
Plant Examples Biogas upgrading plant energy crops 1400 Nm3/h
PSA Biogas Upgrading Process Municiple waste biogas upgrading / ultra low noise level
Plant Examples Biogas upgrading plant container inside
Plant Examples Container assembly in the workshop
Thank you for your attention Contact : www.carbotech.info alfons.schulte@carbotech.info