Biomass Power System. Dr. Sahataya Thongsan. School of Renewable Energy Technology Naresuan University, Phitsanulok, Thailand

Transcription

1 Biomass Power System Dr. Sahataya Thongsan School of Renewable Energy Technology Naresuan University, Phitsanulok, Thailand 1

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3 Downdraft Gasifier

4 Current Gasifier Projects Most gasification work is for large scale power plants Small Scale gasifiers: Finland, Sweden, Thailand, India, USA

5 Application of biomass gasified power generation system 5

6 Types of biomass power plant Steam boiler Gasification 6

7 Biomass boiler power plant 7

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11 Biomass Power Plant in Thailand

12 Biomass gasification gas engine (BGGE) Plant 12

13 3 kw biomass power plat

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19 150 kwe Biomass Power Plant at Chiang Rai 19

20 Gasifier 20

21 Cleaning System 21

22 Cleaning System

23 Cleaning System 23

24 Biomass storage

25 Waste water treatment 25

26 Engine Room 26

27 Biomass Power Plant at SERT

28 Biomass Power System Biomass Gasifier Producer Gas Gas Engine Generator AC

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37 ผลการทดลอง

38 Biomass Power System Termo meter Hopper TM Cyclone Mist Saw-dust Wet Seperator Filter Scrubber FM Blower (starting) Gasifier Pump Tar Water Water Blower Gas Meter Inverter Flare Tower Inverter Air-Gas Mixture Air Cleaner Water Gas Holder Exhaust Gas TM Diesel Generator Set

39 Main factors Gasifier effiicency 70% Initial Cost Technology 20% Economic Cost of energy Gas enginegenerator efficiency 28% Plantation Operating cost Waste water Storage Biomass supplying system Environmental Impacts Logistics/ Harvest Air pollution Noise

40 Why gasification is appropriate? Technology is mature. To crease jobs and skill To install and operate Biomass gasification technologies The know-how is available investment are low. not characterized by daily fluctuation of energy supply.

41 25 kw Biomass Gasifier Generation System The system comprises three main parts 1. Gasifier 2. Gas engine 3. generator Biomass Gasification system Cleaning producer gas Diesel Engine The schematic of biomass conversion to electricity Generator AC 3-Phase

42 The technical performance can be calculated using the equation below. = gasifier x engine x generator where = the efficiency of entire system gasifier engine generator = the efficiency of gasifier = the efficiency of diesel engine = the efficiency of generator

43 Max. electrical output kva kva kw cosθ 25 kw kva where cos θ 0.8

44 1. Generator Specific Generator can provide electricity 25 kw kw 3V Icosθ p p 25 kw (3 x 230 x 46 x 0.8)/1,000 kva

45 Generator Specification of this system Ratting :31.25 kva, V volt,46 A, 50 Hz 1,500 RPM

46 2. Engine η η v η t η m v t m = the efficiency of entire system = the volume efficiency = the thermal efficiency = the mechanical efficiency

47 Max. mechanical output of engine P M.max. P M.max. kva cosθ kva 0.8 P M.max. 39 kwm

48 The engine efficiency The engine efficiency depends partly on the compression ratio. For a compression ratio of 9.5:1, the engine efficiency can be estimated at 28 percent.

49 The thermal power in the gas Pg Pg p m kw kw Pg 139 kw

50 The thermal power in the gas The heating value of the gas is taken at : 4800 kj/m 3 Therefore the real gas intake (m 3 /s) = P g HV g = 139 kj/s 4800 kj/m 3 The real gas in take = m 3 /s

51 At 1500 rpm, for well designed and clean air inlet manifold, ɳ v can be taken at 0.8 Therefore the maximum gas intake is = 0.029/0.8 m 3 /s The maximum gas in take = m 3 /s 51

52 Max.air/gas intake Max.Air/gas in take 1/2 rpm D m /s - rpm of the engine = D = Displacement volume in cylinder of the engine (l)

53 Max.gas intake Max.gas in take 1/2 rpm D m 3 /s - Air/gas ratio (stoichiometric) = 1.1 : 1.0 The real gas in take is (max.gas in take) x (volumatric Efficiency) The realgas in take (max.gas in take) η v

54 volume flow of the gas,m 3 /s Q g (volume flow of the gas, m 3 /s) depends on - rpm of the engine - Displacement volume (D) in cylinder of the engine - Air/gas ratio (stoichiometric)

55 Max.gas intake Max.gas in take 1/2 rpm D 1.0 m /s m 1/ D 1.0 3/s D = 6.09 L

56 3. Design calculation of downdraft gasifier The gasifier will be designed for operation in conjunction with the engine 3.1 Biomass consumption gasifier The thermal efficiency of the gasifier is taken at 70% Thermal power consumption (full load) = P g /0.7 = 139 kw/0.7 = kw

57 Heating value of biomass (14% moisture content): From DEDE reported that LHV of eucalyptus residual = MJ/kg = 17,300 kj/kg Biomass consumption gasifier = /17,300 = kg/s = x 3600 kg/h = 41.4 kg/h

58 So the installation under consideration uses = 41.4 (kg/h)/25 (kw) = kg biomass to produce 1 kwh electricity

59 3.2 Reactor Design For a double throat gasifier hold: B g max. 0.9 m 3 /cm 2 h gas intake engine surface area " throat" B g max. 0.9 m /cm Where B= heart load of Gasifier 3 2 h m /s s

60 S= surface area throat = 145 cm 2 S = 145 cm 2 = r 2 =1/4 x(d throat ) 2 x cm 2 = r 2 =1/4 x(d throat ) 2 x3.14 (d throat ) 2 = (145 x 4)/3.14 = 185 d throat = 14 cm

61 4. Oxidation Zone 4.1) Chemical components of eucalyptus Proximate Analysis (%) Ultimate Analysis (%) Volatile matter (%) Fixed Carbon (%) Carbon (%) Hydrogen (%) 5.91 Ash (%) 1.51 Oxygen (%) Nitrogen (%) 0.94 Sulfur (%) -

62 4.2) Chemical formular of eucalyptus Substance % kg/(kg/mole) Mole mole/mole of C C / H / O / N /

63 4.2) Stoichiometric Air Fuel Ratio - Complete combustion equation C A H B O C N D S E + [A+B/4+E-C/2]O 2 + (0.79/0.21)[A+B/4+E-C/2]N 2 [A]CO 2 + [B/2]H 2 O + [E]SO 2 + {(0.79/0.21)[A+B/4+E-C/2]+D}N 2 + H eat CH 1.61 O N [(X)O (X)N 2 ]

64 Stoichiometric Air Fuel Ratio - Complete combustion equation C A H B O C N D S E + [A+B/4+E-C/2]O 2 + (0.79/0.21)[A+B/4+E-C/2]N 2 [A]CO 2 + [B/2]H 2 O + [E]SO 2 + {(0.79/0.21)[A+B/4+E-C/2]+D}N 2 + H eat CH 1.61 O N [(X)O (X)N 2 ] X = A+B/4+E-C/2 X = 1 + (1.61/4) + 0 (0.837/2) = CH 1.61 O N [(0.984)O (0.984)N 2 ] [ ]

65 Stoichiometric Air Fuel Ratio - Complete combustion equation Eucalyptus 1 kg and air for complete combustion 4.95 kg Equivalent Ratio = for gasification Biomass 1 kg use air = x 4.95 kg Eucalyptus 1 kg air = kg Air/Fuel Ratio, A/F = kg Air/kg Fuel At T= 30 C, P= 1 atm Air density (P) = 1.16 kg/m 3 Air for producer gas = /1.16 = 1.09 m 3 Air/kg Fuel Eucalyptus 1 kg and air for gasification 1.09 m 3

66 Thank You for Your Attention 66