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The Development of Waste-to-Energy Technologies around the World

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1 The Development of Waste-to-Energy Technologies around the World
Waste to Energy Workshop - QCAT San Shwe Hla| Senior Research Scientist 23rd June 2014 Energy technology

2 About today presentation
Current Status for MSW Generation/Management around the World Development of Waste-to-Energy Technologies Brief History of Waste-to-Energy Process and Environmental impacts Conventional and Advanced Incineration Technologies Novel Gasification-based WtE Technologies Comparison between Conventional and Novel WtE Technologies Main Drivers for Practices of WtE Summary and Conclusions (Notes: Economic of WtE is not included) The Development of Waste-to-Energy Technologies around the World| San Shwe Hla | Page 2

3 What a Waste! Waste is an unavoidable by-product of our modern days living. Waste generation increases as GDP increases. MSW generated continues to increase. Current global MSW generation levels are approximately 1.3 billion tonnes per year. EAP = East Asia and pacific region (70% from China) LAC = Latin America & the Caribbean ECA = Eastern and Central Asia MENA = Middle east and north Africa SAR = South Asia Region AFR = Africa Region Exception – Taiwan (Singapore, Korea) is one of the few countries who manages to reduce MSW waste 2000  8.7 m ton, 394 kg /capita 2010  7.95 m ton, 344 kg/capita Japan maintain well around 400 kg/capita for 20 years ( ) Reference: Tanaka, M. 2009; Hoornweg & Bhada-Taka, 2012; US EPA, 2013: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 3

4 MSW generation per capita, selected countries
Reference: National Waste Report, 2010: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 4

5 What is Municipal Solid Waste (MSW)?
This is domestic waste that is generated by household kerbside-collected material and local government street sweeping, maintaining litter bins and public parks and gardens. It includes food wastes containers (product packaging) yard wastes other miscellaneous inorganic wastes. Such as appliances newspapers clothing boxes office and classroom paper furniture wood pallets rubber tires cafeteria wastes Typical MSW composition (Australia) Reference: Australian Bureau of Statistics: Australia’s Environment: Issues & Trends, 2006 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 5

6 Some Novel Technologies
The functional elements of MSW Landfilling/ Dumping Recycling/ Reused/ Composting Thermo-chemical Treatment Landfill gas capture – Some of methane released in Landfill sites are captured in the modern sanitary landfills that are provided with a gas collection network Incineration Some Novel Technologies The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 6

7 The Management of MSW in Europe
Reference: European Waste to Energy Plant Market, 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 7

8 The Management of MSW in Selected countries
Reference: MSW Management in Asia & the Pacific Islands, 2014 TEPA, McCrea et al, 2008 US EPA 2013 National Waste Report 2010 (Environment Protection and Heritage Council (EPHC), 2010) Victorian Local Government Annual Survey ( )- Published by Sustainable Victoria NSW Local Government Waste and Resource Recovery Data Report State of Waste and Recycling in Queensland 2012 (Department of environment and Heritage Protection) The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 8

9 Incineration of MSW Major Benefits Major Drawbacks
The first incinerators for MSW were built in England in 1874, in New York in 1885. Large scale MSW incinerator was mounted in Hamburg in 1895. Major Benefits Major Drawbacks Reducing the amount waste (about 70% - 80% in mass) and (80% -90% in volume), if compress (90-95%). Significant reduction of landfill space- 30 times less (incineration does not completely replace landfilling). High investment and operating cost Emission in flue gas & fly ash Amount of mass residues and impurities in bottom ash Public’s view on WTE Other benefits- Reduce GHGs Reducing fossil fuel use by substituting energy recovery from waste Concentration of inorganic contaminants for safely Utilization of recyclables from the thermal residues (e.g. metals from bottom ash and slag) Other Drawbacks - Especially higher initial cost than landfill Some technical issues, require good technical skill some problem with heat recovery systems ( boiler fouling, erosion, corrosion) a The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 9

10 A very brief history of WTE
Combustion chamber with fix grate 1900 1900 1920 Development of moving grate/ Stoker grate Incinerators’ smoke & odors were accepted as a necessary evil 1930 First rotary kiln in US 1950 Public still satisfied as long as the flue gas is invisible 1950 Fluidized bed technology Introduced 1960 CAA 1970 Awareness of toxic effects of dioxins & furans TA-Luft - Flue gas becomes invisible when combustion conditions is improved and fine dust is removed below 100mg/Nm³ Until 1960s, Little was known about the environmental impacts of the waste discharges and air emissions form MSW incinerators. Dioxin accident at the chemical plant in Seveso, Italy, 1976 trigger the awareness of dioxin effects. - CAA- Clean Air Act (1970)- US mainly with acid gas issues TA-Luft (1974) German emissions codes In 1980s waste incineration plants became the symbol of environmental contamination as dioxins were found in flue gases and fly ahses. - BlmSchV (1990) Germany Combustion of MSW grew in the 1980s, with more than 15 percent of all U.S. MSW being combusted by the early 1990s.  The majority of the non-hazardous waste incinerators were recovering energy by this time and had installed pollution control equipment.  With the newly recognized threats posed by mercury and dioxin emissions, the EPA enacted the Maximum Achievable Control Technology (MACT) regulations in the 1990s.  As a result, most existing facilities had to be retrofitted with air pollution control systems or be shut down. This action required the use of good combustion practice at all facilities, set lower particulate emissions limits to control metals and established emission limits on nitrogen oxides (NOx), organics, HCL, SO2 and opacity. 1980 1980 Advanced WTEs (moving grate) with complex cleaning systems EU- 89/369 1990 BImSchV 1990 USEPA- MACT 2000 EC 2000/76 Slagging operating started 2000 Melting in WTE is mandatory in Japan The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 10

11 Fixed grate incinerators
Simple technology with a fixed metal grate over an ash pit below. Brick-lined cell ovens, opening in the top or sides for loading, another opening in the side for removing the solid residues. Low efficiency , high emissions. The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 11

12 Moving grate incinerators (Stokers)
Traveling grates support the fuel, while conveying it from the front feeding to the ash-discharging side. Primary airs under the grate for primary reactions distributed differently Secondary airs above the grate for post-combustion. The most common, the most proven technology 84% of Japanese WTE (33 mtons/year) 91% of European WTE , almost all of US WTE It was initially designed for coal firing and adapted for MSW incinerations. There are several different grate designs- including forward movement, backward movement, double movement, rocking and roolers. Advantages No need for prior sorting or shredding Wide ranges of fuels (composition and calorific values) Each furnace can be built with a capacity up to 1,200 t/day The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 12

13 Fluidized bed Incinerators
Waste mixed with inert materials are fluidized by air. High thermal efficiency up to 90%, suitable for wide range of fuel and mixtures of fuel (sludge & solid waste) Pre-treatment of waste always required Suitable for RDF. 6% of European WTE 80 plants in Japan (Ebara) Advantages suitable for wide range of fuel and mixtures of fuel and can handle liquid or solid waste either in combination or separately. Relatively low capital and maintenance costs due to a simple design concept Dis-advantages A less common technology for waste incineration Relatively strict demands to size and composition of the waste, which usually requires through pretretment The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 13

14 Rotary Kiln Incinerators
A slight inclined shaft-furnace operating (generally) in a co-current mode. The waste are transported through the furnace by rotations. Long retention, good thermal isolation, and high excess air. Applicable for hazardous waste, chemical waste and dry sewage sludge incinerations. The capacity 2.4 t/day  480 t/ day. Hitachi Zosen- Kiln Incinerator Advantages No need for prior sorting or shredding Wide ranges of fuels (composition and calorific values) Overall thermal efficiency up to 80% Dis-advantages A less common technology for waste incineration Limited maximum capacity The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 14

15 Advanced Moving Grate MSWI system
Conventional one – % (Gross efficiency) Advanced one – % (Gross efficiency) In comparison, the average efficiency of plants in service in Europe lies at about 13%. (H. Spliethoff, Power generation from solid fuels: Springer, 2010.) Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 15

16 Moving Grate Incineration System
Mass balance of MSW Incineration 7 – 8.6 ton of flue gas (Need cleaning before stack) 20 – 40 kg of fly ash (highly toxic) 1 ton of MSW Moving Grate Incineration System 6.2 – 7.8 ton of Air Data are for typical mechanical grate incineration generates (EU conditions) Bottom ash contains stones, glass, cans, ash proper Flue gas, CO2, H2O, N2 & O2 Incomplete combustion leads to formation of CO, total organic carbon (TOC) & black carbon (or) soot 250 – 350 kg of bottom ash (contains heavy metals, salts, chloride & organic pollutants) 5 – 15 kg boiler slag 5 – 15 kg neutralization salts Reference: Incineration Technologies, 2012 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 16

17 About Dioxin/Furan Polychlorinated dibenzo-p-dioxins (PCDDS) DIOXINS
Polychlorinated dibenzofurans (PCDFs) FURANS Small amounts of PCDD/Fs are formed whenever carbon, oxygen and chlorine are available at certain operating temperatures Dioxins are highly toxic and can cause reproductive and developmental problems, damage the immune system, interfere with hormones and also cause cancer. Sources of Dioxin  Industrial processes Waste incineration Smelting Chlorine bleaching of paper pulp The manufacturing of some herbicides and pesticides 2,3,7,8-Tetrachlorodibenzo-p-dioxin Other sources Volcanic eruptions Forest fires Backyard trash burning The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 17

18 Flue gas cleaning Because of the very heavy (public and political) pressures, MSW incineration (at present) is the most regulated and best controlled form of combustion. Some milestones in the evolutions of emission limits values from Germany and European Reference: Incineration Technologies, 2012 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 18

19 Dioxin/Furan in MSW incinerations
Dioxins were discovered on MSW incinerator fly ashes and flue gases in (Olie et al. 1977). MSW incinerators were major sources of dioxins emissions in 80s. The dioxins became an extremely large problem in Japan, US, Europe form around the mid 1990s. Emissions amount reduced 99% since then. - Poor operating conditions not only lead to more dioxins but also to a prolonged increase in dioxins (Absorb on boiler deposits) Reference: Deriziotis 2004; Kawamoto, Yokohama National University The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 19

20 Required reduction of emission levels
Pollutant Concentration in raw gas from boiler(mg/Nm³, dry) Maximum admissible at exhaust (mg/Nm³, dry) Removal efficiency required (%) Dust 2,000 – 10,000 (Stokers) 10,000 – 50,000 (FB) 10 99.9 Fly Ash 1,500 – 2,000 HCl 300 – 2,000 >99 SO2 200 – 1,000 5 99.5 NOx 200 – 500 70 86 HF 2 – 25 1 96 Hg 0.2 – 0.8 0.01 99 Cd , Tl + other metals 2 – 15 0.05 >99.5 Dioxins and furnas (ng I-TEQ/Nm³) 0.5 – 5 0.1 98 TEQ = Toxic equivalent quantity Reference: Achternbosch & Richers (2002); Quina, et al. 2011 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 20

21 Modern MSWI with advanced cleaning system
B – Quick cooling of gas prevents the dioxin reformation C – Fine particulates, dust, Fly ash, SOx, HCI (absorbed) are eliminated D – HCl, SOx, Hg are removed E– Discharge heavy metal and the dioxin in the flue gas absorbed in activated carbon. F – NOx revmoved and, dioxin decomposed and removed. C- The fly ash in flue gas, as well as the SOx and HCI that has reacted with and been absorbed by such substances as slaked lime, are eliminated when they attach to the cylindrical filtration cloth D - Hydrogen chloride and sulfur oxides, as well as mercury, are removed from the flue gas. By the reheater, white plumes can be prevented. E - Discharge the dioxin in the flue gas absorbed in activated carbon. Activated carbon charged from the upper part of the tower is moved down periodically and discharged at the bottom of packed bed. F- Besides removing the nitrogen oxide contained in flue gas as nonpolluting nitrogen and water by blowing ammonia gas and catalyst, dioxin can be decomposed and removed. Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 21

22 Main Drivers for Adapting Novel/ Gasification Technologies for WTE
1995 UN Environmental Program published that 4 kg out of 10kg TEQ of dioxin came from Japan. New regulations and policies between in Japan were main drivers for the development and installation of new gasification and melting systems. E.g. new dioxin regulation in 2003 limited 1 ng TEQ/Nm³ (for existing plants) and 0.1 ng TEQ/Nm³ (for new plants) [up until the end of 2002, 80 ng TEQ/Nm³ was still acceptable] & melting process in WTE becomes mandatory in Japan. There are currently over 120 gasification based (ash melting) WTE plants operating in Japan with a total capacity of 6.9 million tonnes / year. Main purposes are to reduce dioxin emissions (and other harmful substances) and to produce glassy slag (to improve ash quality). Features of melting system - High-temperature combustion controls emissions of dioxins and other harmful substances - Low air ratio produces low volume of exhaust gas - Recycling of the molten slag and metals reduces final landfill volume High energy recovery efficiency is achieved. The technology of melting MSW incinerated ash became of interest to the national government, as it promised to reduce the level of dioxins in incineration by-products, prevent the leaching of heavy metals from incinerated ash into the ground, and achieve both landfill volume reduction and effective energy use. The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 22

23 Gasification & Melting
Routes for Ash Melting System Melting Slag Recycled in construction work With ash melting Fly ash Landfill (~2%) Waste Incineration Bottom ash, fly ash Without ash melting Landfill (>20%) 100% Power generation, Heat utilization (a) Incineration + Melting Fly ash Landfill (~2%) Gasification is compared to conventional incineration with ash melting system Has higher energy conversion efficiency Has low air ratio (cost-effective) Better emissions of raw fuel gas Waste Gasification & Melting Slag Recycled in construction work 100% Power generation, Heat utilization (b) Gasification & Melting Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 23

24 Installation of ash melting process in MSW-to-Energy plants in Japan
Gasification is compared to conventional incineration with ash melting system Has higher energy conversion efficiency Has low air ratio (cost-effective) Better emissions of raw fuel gas Gasification & melting Incineration Reference: Professor Yoshikawa, Tokyo Institute of Technology The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 24

25 Type of gasification based WtE Plants
There are over 120 WtE plants using novel/gasification technologies in Japan & 13 plants in Europe. Fixed beds (Direct Melting System) Fluidised Bed Gasification and Ash Melting Pyrolysis/ Gasification & Melting Moving Grate Gasification Plasma Gasification The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 25

26 Nippon Steel The Largest supplier of gasification based WTE plants in Japan 33 in Japan 2 in South Korea. Fixed bed, updraft gasifier, Co gasification. 23% overall efficiency Oxygen enriched air Coke (5% wt) and limestone are introduced to the gasifier along with the waste. Residue char and coke burned at the bottom of the bed with oxygen-rich air (36% of O2) to produce the temperature up to 1800°C. Waste dry at the top section at temperatures between 200 and 300°C Toxic heavy metals are volatilized and distribute to fly ash Few toxic heavy metals remain in slag and metal Low HCL and SO2 concentration Raw syngas is post-combusted in a recovery boiler with heat/electricity production via steam turbine cycle (Ref: Arena 2012). Reference: Nippon Steel & Sumikin Engineering Co., Ltd, 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 26

27 Process Flow – Nippon Steel
Reference: Nippon Steel & Sumikin Engineering Co., Ltd, 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 27

28 Shin Moji Plant – NS largest gasification plant
Reference: Nippon Steel & Sumikin Engineering Co., Ltd, 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 28

29 JFE- Fixed Beds WTE Merger of Kawasaki steel and NKK.
Fixed bed types under JFE is similar to Nippon Steel Currently 10 operational plants using MSW, RDF as feed stocks Raw syngas is post-combusted in a recovery boiler with heat/electricity production via steam turbine cycle (Ref: Nishino 2009). Reference: Professor Yoshikawa, Tokyo Institute of Technology The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 29

30 EBARA- Fluidized bed gasification and Ash- melting Process
Shredded MSW is first gasified inside fluidized bed gasifier operated under a low air ratio. Combustion of syngas in second reactor for ash melting. No oxygen enrichment. Fuel preparation required. Currently 11 plants in Japan & 4 in Korea (mostly for MSW and some for industrial wastes) Similar WTE process has also being supplied be Kobelco (15 plants) & Hitachi Zosen (8 Plants) An inclined distributor plate is used with a number of separate fluidizing air supply chambers to provide differential air flows across the bed. This technology is industrially proven for the processing of MSW, RDF, automobile shredder residue (ASR), waste plastics, sewage sludge and medical wastes. EBARA fluidised bed gasifier is called (Twin Internally revolving Fluidized bed gasifier” (TIFG), which is internally circulating fluidized bed. Kobelco & Hitachi Zosen used bubbling fluidized bed. Operating temperature of EBARA system is °C (gasifier), °C (ash melter) Reference: Professor Yoshikawa, Tokyo Institute of Technology The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 30

31 EBARA Fluidized bed gasification (TIFG) & Ash melting system
- EBARA's fluidized-bed gasification and ash melting system is composed of our proven fluidized-bed technology and a circulating ash melting furnace in which ash is melted by the waste energy, turning it to slag which can be recovered and utilized effectively. - The internally circulating function inherited from fluidized-bed incinerator technology makes it possible to recover incombustibles like ferrous material and aluminum in an unoxidized state, further reducing final disposal into landfill. - The low-excess-air high-temperature combustion at the circulating ash melting furnace also reduces emissions of dioxins, and resulting higher boiler efficiency makes the system suitable for high-efficiency power recovery. Mixed treatment of ash from other facilities, sludge or refuse dug up from final disposal sites are also possible, helping reduction of final disposal and also effective use of final disposal site Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 31

32 EBARA Pressurized twin internally circulating Fluidized bed gasification system (PTIFG)
Almost all of the WtE plants in Japan generate the electricity as a main (end) product of their waste management system. The only exception is that Ebara use their pressurized twin internally circulating fluidized-bed gasification system (PTIFG) to gasify plastic waste in order to produce a syngas containing a certain level of hydrogen high enough for Ammonia synthesis -Unlike the power gasifier, mixture of oxygen and steam are used as gasifying medium under high pressure in this system. A such facility was delivered to Showa Denko in year 2003, and 195 ton per day of collected plastic waste are gasified and processed into 175 tons of liquid ammonia as well as into other products in Kawasaki City Two gasifiers, with O2 and Steam as gasifying medium under high pressure. Relatively H2 riched syngas for NH3 systhesis Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 32

33 JFE- ThermoSelect 30.7% H2, 32.5% CO, 33.8% CO2, 2.3%N2 8.5 MJ/Nm³
This is the process flow diagram of ThermoSelect waste gasification technologies. The waste is transported to a Press using overhead cranes. Then the Press compacts the waste into a plug, removing much of the air and evenly distributing moisture in the waste. The waste plugs are pushed into the Degasification Channel and are moved forward by subsequent plugs. The plugs are heated by the radiant heat from the High Temperature Chamber. As each component of the waste reaches its vaporization temperature, it is transformed into gas which moves down the Channel toward the High Temperature Chamber. At the end of the Degasification Channel, a carbon char and inert components of the waste remain and fall into the High Temperature Chamber. 95% pure oxygen is added through nozzles and the carbon char is transformed into synthesis gas. The inorganic material becomes molten, reaching temperatures of 2,000 degrees C. As the gases exit the upper section of the High Temperature Chamber at 1200°C , they are shock quenched in less than one second to a temperature below 70°C to ensure that dioxins and furans do not form. The synthesis gas is cleaned to remove sulfur, heavy metals and other impurities and becomes a usable fuel source. The molten material is shock cooled at the end of the Homogenizer and becomes sand-like material and metal pellets. No additional fuel, no additional heat source by electricity or plasma required. But 95% of O2 required. Because of O2 feed plants, Heating value of syngas is quite high. Reference: Frank Campbell, IWT, 2008 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 33

34 JFE- ThermoSelect.. Cont.
Develop in Switzerland between ( ). Demonstration facility in Fondotoche, northern Italy (100t/d) ( ). Commercial scale in Germany ( , test phase), ( ) full operational. Shut down due to litigation between the supplier Thermoselect S. A. & The owner EnBW (or) due to emissions issue. Currently, 7 ThermoSelect facilities are being operated in Japan by JFE treating MSW and IW. (5 plants powered by gas engine, 2 plants by steam turbines) JFE have stated that they no longer offer the technology as it is too expensive. - Prof. Themelis is founder and Chairman of the Waste to Energy Research and Technology Council. - Director, Earth Engineering Centre, Columbia University Reference: Frank Campbell, IWT, 2008 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 34

35 Takuma-Waste pyrolysis gasification and melting system
Wastes are first pyrolysed using a pyrolysis drum and using a vertical downflow-type rotary melting furnace, conversion of ash to molten slag. - This technology uses a pyrolysis drum with high-temperature air pipes in it for pyrolysis. - Waste is crushed, fed to the pyrolysis drum while being compacted, and then pyrolyzed and gasified for about one hour in oxygen-free conditions. The long retention time makes it possible to absorb variations in the refuse quality, enabling stable operation. Steam is recovered from high-temperature exhaust gas and is used for turbine power generation. - Company K (90 tons per day 2,000 kW of power generation), City K (81 tons per day × 2 1,600 kW of power generation), 3 other facilities “Kiln-type pyrolysis gasification and melting furnace” (Mitsui) - This technology is used to modify waste into pyrolysis gas and char and allow the waste to melt thermally by itself, which reduces the consumption of fuel for combustion. This technology uses a kiln as a gasification furnace. [Objective and application of the technology] Waste is gasified, melted, and recycled as ash for high-efficiency power generation. [Characteristics of the technology] - An indirectly heated kiln is used to pyrolyze and gasify waste. - Domestic: 7 facilities Overseas: 2 facilities (licensed) The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 35

36 ENERGOS A leading European WTE system.
Norway (6 plants), Germany (1), UK (1) Waste are pre-treated prior to use Gasification took place on moving grate High temperature oxidation in a secondary chamber End used: Thermal (mostly) 8 Waste are pre-treated prior to use (Shredding & magnetically separating ferrous materials for recycling). Fuel is fed into the gasification chamber via a fuel hopper. - The thermal conversion of waste to energy happens in two stages. In the first stage, fuel enters a primary chamber, where gasification of the fuel takes place and a syngas is produced. The syngas is transferred to a secondary chamber where high temperature oxidation takes place.  At each stage of the process a high degree of control is exerted to ensure that emissions to the atmosphere are minimised. As a by-product of the process, bottom ash is discharged from the primary chamber at the end of the grate The HRSG consists of a water-tube boiler, a smoke-tube boiler and an economiser. Depending on how the energy is to be utilised, the boiler system is designed to deliver saturated steam (for the delivery of heat) or superheated steam (for the production of electricity). Most plant of Energos does not generate electricity, rather all steam produced is piped to Industries. Isle of Wight Plant, UK (Electricity): 1.8 MW 7 Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 36

37 Plasma gasification The use of plasma torches is not new.
The use of Plasma torch in gasification of solid waste is new. Plasma is simply a high-temperature ionized gas created within a plasma torch that is both thermally and electrically conductive. AlterNRG/WPC design the temperature of the plasma plume would be between 5,000 °C and 7,000°C. In plasma gasification process, ash melting occurs in the absence or near absence of O2, prohibiting combustion. Two types of plasma gasification: Plasma assisted gasification Plasma assisted gas cleaning & melting MSW ash (from incineration plants) melting using Plasma torch are not considered as plasma gasification. Plasma is one of the four states of matter are observable in everyday life: solid, liquid, gas and plasma. Plasma consisting of a mixture of electrons, irons and neutral particles, although overall it is electrically neutral. Gas ---- Ionization  Plasma: Plasma --- Deionization  Gas A gas is usually converted to a plasma in one of two ways, either from a huge voltage difference between two points, or by exposing it to extremely high temperatures. Plasma technology involves the creation of a sustained electrical arc by the passage of electric current through a gas in a process referred to as electrical breakdown. Because of the electrical resistivity across the system, significant heat is generated, which strips away electrons from the gas molecules resulting in an ionised gas stream, or plasma. The use of plasma torches is not new. Westinghouse Plasma Corporation (WPC) began building plasma torches for NASA in conjunction with the Apollo Space Program as long ago as the 1960s. Commonly used gases air, N2, CO2, steam and argon. MSW ash (from incineration plants) melting using Plasma torch are not considered as plasma gasification. Kinura, Japan  MSW Ash  50 TPD  1995 Kakogawa, Japan  MSW Ash  30 TPD  2003 Shimonoseki, Japan  MSW Ash  41 TPD  2002 Imizu, Japan  MSW Ash  12 TPD  2002 Maizuru, Japan  MSW Ash  6 TPD  2003 - Westinghouse Plasma Corp Plasma Torch (Willis et al 2010) The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 37

38 Plasma assisted gasification
Gasification and melting occur inside a single rector. Operating temperature are hot enough to drive the gasification reactions and brake down tars and higher MW compounds into CO and H2. Updraft type fixed bed gasification Torch temperature ≈ 5,000°C – 7,000°C Bulk bed temperature at base ≈ 2,000°C Molten slag temperature ≈ 1,650°C The syngas temperature ≈ 890°C – 1,100°C Utashinai Plant  MSW (50%) + ASR (50%)  165 tpd  2003 Mihama-Mikata  Dried sewage sludge (20%) + MSW (80%)  22 tpd, 2003 ASR = Automotive shredder residue Those two Japanese plants were built by Hitachi Metals under licence from Westinghouse Plasma Corporation (WPC). AlterNRG acquired WPC in AlterNRG is a Canadian company. - ALTER NRG Plasma Gasification Reactor (Ref: Alter NRG) Reference: Willis et al 2010; Wood et al 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 38

39 Plasco Plant Plasma assisted gas cleaning and ash melting to treat MSW in Ottawa (100 tpd) by Plasco Energy Group. Gasification and plasma ash melting occur separately Plasco Energy Group (Canadian company) is currently developing opportunities across North America, Europe and China. Presently, Plasco owns and operates two facilities a 100 tonne-per-day commercial demonstration facility in Ottawa, Canada, and a 5 tonne-per-day research and development facility in Castellgali, Spain. Drawback of single stage plasma Heat transfer, Scale and modularity  as the plasma arc is a relatively localized source of heat generation. Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 39

40 CHO Power WtE Plant CHO-Power (& Europlasma) process consists of a primary gasifier (a moving grate system) with plasma assisted syngas cracking reactor and ash melting unit. First commercial plant in Morcenx, near Lyon, France. 37,000 tpa (IW) + 15,000 tpa (WC) - The CHO-Power process comprises a primary gasification stage based on a moving grate system from which syngas is produce which passes through a plasma polishing reactor where the high temperature and oxygen free conditions ‘crack’ the higher molecular weight molecules and any liquid hydrocarbons present to produce a cleaned syngas comprising CO, H2 and traces of CH4. - As an optional addition a second plasma reactor can be incorporated to melt the ash (inorganic) residues from the gasifier and produce a vitrified slag that could be recycled into civil engineering applications. The cleaned syngas is then directly converted to electricity via gas engines. - 37,000 tpa (IW) industrial waste 15,000 tpa (WC) wood chips Europlasma has supplied their plasma melting system to a number of leading incineration companies in Japan for bottom ash melting duties and therefore the company would be confident about that part of the process. The performance of the grate gasifier is unknown at this time and Europlasma will need to demonstrate 6 months of continuous operation before the process could be consider fully proven. The investment for the Morcenx plant was in the order of 40 million Euros. Reference: The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 40

41 Utilisation of Slag and metal
Reference: Professor Yoshikawa, Tokyo Institute of Technology The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 41

42 Slag recycling The slagging of the inorganic content of the waste to produce a vitrified slag material has enabled the production of a re-usable material for civil engineering applications and metallurgical processing. The slag is converted into products such as paving slabs, roof tiles, etc which have passed the relevant Japanese regulatory tests to be accepted as building products, as shown in the following table: The vitrified slag has been utilised in Japan in several construction applications (see photographs below): ■ as a replacement aggregate; ■ mixed with asphalt for road and car park surfacing; ■ manufacture of roof tiles; ■ manufacture of paving slabs; ■ manufacture of concrete blocks. Reference: Nippon Steel & Sumikin Engineering Co., Ltd, 2013 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 42

43 List of proven gasification based WTE plants
Company Type of WTE No of plants End Uses Remarks Nippon Steel Fixed bed-Direct Melting 33 (2) ST Enriched O2, 5% Coke JFE (NKK) 10 (1) Enriched O2, Coke Kawasaki Giken 5 High Concentration O2 JFE (ThermoSelect) Kiln Pyrolysis-Gasification-Melting 7 GT-E, ST 95% O2, Waste Compression Mitsui 7 (2) Waste are shredded first. Takuma Co. Ltd 2 Ebara Co. C-Fluidised gasification- Melting 11 (4) Kobelco Co. Ltd B-Fluidised gasification- Melting 13 (2) Hitachi Zosen 8 Ebara & Show Denko PTIFG & Ash melting 1 NH3 Pressurized, O2+H2O AlterNRG-Hitachi-M Plasma Assisted Gasification Plasma, MSW-ASR-SS Plasco Energy Plasma assisted cleaning/melting GT-Eng Plasma, MSW CHO-Power-Europlasma ENERGOS Stoker-gasification - Combustion Steam Waste pretreated. No melting. This list excludes demonstration/research facilities, facilities under constructions. All are systems with melting except Energos Auto color – Japan Light blue – Korea Yellow – Ottawa, Canada Deep Blue- Europe Only total 7 plants generate electricity via gas enegine. : Thermoselect (5), Plasco (1), Cho-power (1) According to some reports, emissions from Energos plants are questionable. The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 43

44 World’s first waste-to-biofuels facility
Enerkem waste to biofuels and chemical facility at Edmonton Opened on 4th June, 2014 60% of waste into biofuels and chemicals 100,000 tonnes/year to MSW into 38 million liter of biofuels 70$/ton landfill, 75$/ton WtF Manual & mechanical Separating Shredded Organic waste Waste Gasification Syngas Clean syngas Ethanol Inert Biofuel facility Methanol Chemical intermediates Reference: Edmonton Journal , 5 June, 2014; The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 44

45 What are the main drivers of WTEs?
Government regulations Public Health Environmental issues Emission controls Reducing land fill areas Cost of WTE Vs tipping fees Electricity generation from MSW is not a main driver. It is one of the products while reducing amount of wastes. Let’s see an outermost case. Japan with 800 Plants (310 WtE Electricity) plants utilising 40 million tons MSW annually (80% of total MSW generation). Total install capacity ≈ 1673 MWe (in 2009) ≈ 0.6% of country’s electricity generation - The US Supreme Court rejected the practice of waste flow control which is legal provisions that allow state and local governments to designate the places where MSW is treated and disposed. This rejection then lead to an abrupt halting of the def energy from the waste schemes. No WTE plants built in US between The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 45

46 Tipping fees Vs WTE plants in US
The US Supreme Court rejected the practice of waste flow control which is legal provisions that allow state and local governments to designate the places where MSW is treated and disposed. This rejection then lead to an abrupt halting of the def energy from the waste schemes. No WTE plants built in US between  South Carolina   9,408 Massachusetts   9,450     New York ,319     Florida   ,756 Reference: The 2010 ERC Directory of Waste-to-Energy Plants The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 46

47 WTE Reduces GHG Emissions
Nearly one ton of CO2 equivalent emissions are avoided for every ton of MSW handled by WTE (US EPA) due to Avoided CH4 emissions from land fills. Avoided CO2 emissions from fossil fuel combustion. Avoided CO2 emission from metals production. Consideration also includes emission from vehicles which drives from transfer station to landfill At least 25% of methane escapes to the atmosphere even in the modern sanitary landfills that are provided with a gas collection network Reference: Thorneloe et al, 2006 The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 47

48 Feasibility Study: Requirements for a Successful WTE Project
Research on Technical Feasibility Survey of waste characteristics, LCV and amount of waste Selecting suitable WTE system Estimation of electricity output Plant Location Evaluation of Environmental and Social Impacts GHG Emission/Reduction Effect Plant Emissions Research of legal system and procedure related to environmental assessment Financial and Economic Feasibility The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 48

49 Road Map to commercial scale WtE plant
- Composition - Energy content - Reaction rates Fuel (MSW) characterization Fuel (MSW), Availability - Data collection from local councils - Steam Turbine - Gas Turbine - Combined Cycle - Chemicals - Liquid fuels Selection of type of WtE plant - Choice of plant size & End use Fuel (MSW) preparation methods Lab scale reactor Process Modelling Emissions Vs regulations Cost Analysis - Public acceptance is not included in this road map. no Meet the budget, regulations & WTE performance set yes Pilot/Commercial scale WtE plant The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 49

50 Summary of WTE technologies
Source: Frost & Sullivan analysis Moving grate technology is the most commonly used for WTE (84% Japan, 91% European, almost all of US WTE. Fluidised bed incineration provide higher efficiency with lower emission level. Gasification technology has smaller capacity than incineration but its integration with melting systems significantly amount of reduces WTE wastes (bottom ash). Grate technology is the most commonly used solution for WTE and is based on air. Originally, grate technology was dedicated to incineration of first generation MSW and its aim was to utilize waste material. This technology is characterized by low energy efficiency and high emission of fumes. Currently, grate technology has improved in terms of environmental and thermal parameters. Fluidized bed is based on quasi-sand material and its main benefits are high energy efficiency, complete incineration of input material, low emission levels, and the ability to incinerate MSW with high moisture level. Gasification technology has smaller capacity than grate or fluidzed bed solutions, but this technology is highly energy efficient, creates low level of ash (chars), and its main product is SNG, which is rich in hydrogen and methane. The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 50

51 Current status of gasification of MSW
Technical reliability Limited number of gasification based (melting) plants (~120) are able to offer a proven gasification process for different kinds of solid wastes. Environmental sustainability Gasification is considered as a sound response to the increasingly restrictive emission regulations and towards zero wastes. Economic convenience Usually more expensive in operating and capital costs higher than conventional combustion-based WtE. Recent evidences indicate a convenience of gasification plants for size smaller than about 120 kt/y. The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 51

52 Conclusions & some thoughts
Driving force for WTE options over landfill Tipping fees (Landfill tax, landfill levy) Government regulation regarding with landfilling Driving force for gasification based WTE over incineration WTE Government regulations on specific design of WTE plant (e.g. melting) Tipping fees for WTE bottom ash Emission control and regulations Important factors for establishing WTE plants in Australia Government regulations and policies Public acceptance The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 52

53 - This cartoon is from one of the recent reports of World bank publication series. A Global Review of Solid Waste Management (2012) The Development of Waste-to-Energy Technologies around the World | San Shwe Hla | Page 53

54 Thank you CSIRO Energy Technology
San Shwe Hla The Development of Waste-to-Energy Technologies around the World t e w Thank you


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