Experience is our Technology SmartMill Technology Guaranteeing Particle Size, Quality and Production with On-site Sorbent Milling Experience is our Technology 1
Milling & Feeding Technology STM Line of Mills Roller Mills Hammer Mills Screen Mills Jet Mills Pin Mills Cryogenic Mills Laboratory Mills 2
Milling & Feeding Technology STM Line of Feeders, Injectors & Classifiers Volumetric Feeders Gravimetric Feeders Dry Eductors Wet Eductors Distributors Lump Breakers Dynamic Classifiers 3
Sodium Sorbent Milling Sodium Dry Injection Technology Experience In the 90s, STM led the world in dry grinding for gas cleaning applications by helping a world-leading chemical supplier develop a novel gas cleaning approach using sodium sorbents. STM Serial No. 1. Reggio Emilia Incinerator, Italy Today, STM has more sorbent mill installations than any other mill supplier, exceeding 500 installations. Latest STM Hammermill Design 4
Na Sorbent Decomposition Behavior of Sodium Sorbents at Temperature Sodium Sorbent Decomposition Sodium Bicarbonate 2NaHCO 3 Na 2 CO 3 + H 2 O + CO 2 Trona 2 [ Na 2 CO 3 NaHCO 3 2H 2 O ] 3Na 2 CO 3 + 5H 2 O + CO 2 Acid Gas Neutralization HCl Removal Na 2 CO 3 + 2HCl 2NaCl + H 2 O + CO 2 SO 2 Removal Na 2 CO 3 + SO 2 Na 2 SO 3 + CO 2 and Na 2 SO 3 + 1 /2O 2 Na 2 SO 4 Slide Courtesy of Solvay 5
Gas Cleaning Systems Optimal System for Each Application Combustion Process Sodium Sorbent Type Sodium Bicarbonate Trona Industrial and Hazardous Waste Incineration Biomass Cement Power Water Treatment Metals Recovery Furnace Cremation General Combustion: Heavy Fuel Oil and Natural Gas Municipal and Hospital Waste Incineration Steel and Foundries Glass 6
Gas Cleaning Comparison Characteristics of Various Sodium Sorbents Sodium Bicarbonate Trona Stoichiometric Ratio 0.8-1.4 1.8-2.5 Gas Temperature 120-400 C 135-800 C Reaction Time >2 Sec >4 Sec HCl Efficiency >99% >95% SO2 Efficiency >98% >90% SO3 Efficiency >98% >95% 7
Na Performance curve Variations in Stoichiometry for a Given Efficiency Slide Courtesy of Solvay 8
Na Performance curve Variations in Efficiency for a Given Stoichiometry Slide Courtesy of Solvay 9
Efficiency Factors Some of the Factors that Affect Acid Gas Removal Given the same operating conditions and reaction chamber geometry, stoichiometry and efficiency variations can be reduced down to one main operational parameter - Particle Size Distribution. Achieving the correct sorbent particle size is necessary to achieve the required efficiency. Maintaining the correct particle size yearover-year is necessary to achieve compliance. 10
Sorbent Particle Size Particle Size for SO2 Removal 20 µm PARTICLE SIZE x 10 = 0.93µm x 50 = 5.60µm x 90 = 20.15µm x 97 = 32.29µm x 98 = 37.55µm x 99 = 48.14µm 11
Sorbent Particle Size Particle Size for HCl Removal 30 µm PARTICLE SIZE x 10 = 1.87µm x 50 = 14.64µm x 90 = 33.88µm x 97 = 44.47µm x 98 = 48.19µm x 99 = 53.62µm 12
Na Calcining Calcination occurs at elevated temperatures 13
Sorbent Injection Flowsheet for PC-fired Boiler with Duct Injection 14
Sorbent Injection Flowsheet for PC-fired Boiler with Reactor 15
Sorbent Injection Typical Reactor Designs Single Pass Reactor Double Pass Reactor 16
CFD Optimization Bold Eco - Infratech Reactor Modeling L-14-BEX-02 Need for Distribution Analysis Design 1 Model Results Total Velocity - Centerline Second Reactor Figure 8 Throat Design Double Pass Reactor 0.0 12.0 24.0 36.0 48.0 60.0 Airflow 17
Efficiency Factors Some of the Factors that Affect Acid Gas Removal Gas Flow Factors Temperature Mixing (turbulence) Distribution Sorbent Factors Particle Size Purity Material Integrity 18
Milled Sorbent Challenges On-site Particle Size Reduction vs. Pre-milled Pre-milled Storage silo release Materials handling and transport Particle size (clumping) On-site Milling Maintenance Particle size consistency Operational issues (difficult to keep clean) 19
Basic Milling Technology Dose, Mill, Classify, Propel Components or a typical milling circuit to Duct or Reactor Dosing Element Grinding Element Milled Sorbent Raw Sorbent Feed Propulstion Element Separation Element Positive Pressure Propulsion Air Heat Exchanger 20
Basic Mill Technology What mills have been used before? Pin Mill Uses pins rotating on rotors Screen Mill Uses hammers rotating against a screen Hammer Mill Uses hammers rotating against a track 21
Basic Mill Comparison Mills that should not be used and why Pin Mill: Prone to build-up Difficult to clean pins online Requires frequent and long interventions No classifier to separate fine particles Screen Mill: Prone to build-up Difficult to clean online Requires frequent cleanings No classifier to separate fine particles 22
Basic Mill Comparison Mills that could be used and why Compact Hammer Mill: Easy to keep clean with glycol addition Requires little maintenance Built-in propulsion fan - negative pressure Self classifier to separate fine particles Twin Rotor Hammer Mill: Not as prone to build-up Easy to clean and maintain Twin rotors for higher production Separate dynamic classifier 23
Compact Mill Self-classifying, compact design Flow-through, self-classifying mill coupled to a transport air fan. The self-classifying design makes it a good choice for applications where narrow particle size distribution is not critical. Ideal for low-cost retrofit applications. Operational advantages: Low energy consumption Minimal maintenance needs Compact, small space requirement Ease of installation Automatic operation 24
Compact Mill Limitations Design limitations of a compact hammer mill Limited size single rotor Limits production rate Requires higher velocity Typically used in smaller installations In-line classifier Imperfect control over particle size distribution D 50 particle size ±10-15 µm D 90 particle size ±35-40 µm 25
Basic Twin Hammer Mill Air classifying, twin rotor design Twin rotor, air-classifying mill with a separate transport air fan. The twin rotor design makes it a good choice for applications where mill temperature and particle integrity is not critical, such as calcium-based materials. Ideal for medium/large gas cleaning plants and for low-cost retrofit applications. Operational advantages: Low energy consumption Minimal maintenance needs Compact, small space requirement Ease of installation Basic Hammer Mill Automatic operation 26
Hammer Mill Limitations Mills that could be used and why Older generation mill Medium size twin rotors Limits production rate Requires higher rotor velocities Dynamic classifier Better control over particle size distribution D 97 particle size ±15-20 µm Significant heat build-up Like all ACMs, heat build-up makes it less desirable for milling sodium 27
Other Hammermills Competitive Mill - Positive Pressure and Excess Heat Older generation mill Shroud baffle assembly Requires that first pass milled material flow around it Designed to create circuit for rejects to return to mill hammers Turbulence around shroud baffle plate causes excess heat Dynamic classifier Good control over particle size distribution D 97 particle size ±15-20 µm Significant material build-up Heat causes build-up making it less desirable for milling sodium 28
Typical ACM Popular Air Classified Mill Design for Sorbent Milling 29
Typical ACM Air Classified Mill Internals 30
Typical ACM Air Classified Mill - Design Material + Transport Air Inlet Outlet - Air + Material Classifier Shroud Baffle Assembly Milling Liner Milling Air Inlet Rotor w/hammers 31
Other Hammermills Competitive Mill - Positive Pressure Operation Air + Material Reject Material Return: Turbulence=Heat Heat=Build-up Milling and Classifying Air 32
Example Installation Competitive Mill - Positive Pressure Operation 33
Example Installation Competitive Mill - Build-up due to Overheating of SBC 34
Example Installation Competitive Mill - 2 Mills Replaced with 1 STM Bicarmill 35
Heat Build-up Competitive Mill - Horizontal ACM Design 36
Heat Build-up Competitive Mill - Vertical In-Line Design 37
No Heat Build-up Bicarmill - Horizontal Design 38
Basic Milling Technology Dose, Mill, Classify, Propel Components of a smart milling circuit to Duct or Reactor Dosing Element Raw Sorbent Feed Negative Pressure Propulsion Air Grinding Element Milled Sorbent Propulstion Element Separation Element 39
+ Basic Mill System Elements PLC Feeder Booster Fan Sorbent Injection + + + + Fan/blower Chiller Mill Classifier Traditional Sorbent Milling Component Arrangement Traditional milling systems are made up of several components, each engineered, purchased, installed, wired and controlled separately. Until recently, there was no option that provided a single, integrated milling solution. 40
Mill System Components Feeder - Required for metering the needed amount of sorbent into the mill Mill - Finely grinds the sorbent to improve the efficiency of the scrubbing Classifier - Allows fine sorbent through and returns the large material to the mill Fan/blower - Blows fine sorbent to the injection lances Chiller - Cools the incoming air to prevent sorbent from reacting in the mill Booster Fan - Boosts the pressure of the sorbent transport air PLC - Regulates each element of the milling circuit 41
Site-Assembled Mill Systems Feeder - $40,000 Mill - $90,000 Classifier - $20,000 Fan/blower - $15,000 Chiller - $15,000 Booster Fan - $10,000 PLC - $50,000 Cost of an Assembled Sorbent Milling System Cost of components-only 1000 kg/h sorbent milling system: $240,000 and that does not include installation, wiring, engineering nor 8400 hour guarantee! 42
Site-Assembled Mill Systems Engineering - $30,000 Engineering Review - $20,000 Electrical Installation - $30,000 Mechanical Installation - $40,000 Total Installed Cost of a Traditional Mill System Installed cost for 1000 kg/h sorbent milling system: $240,000+$120,000= $360,000 But still does not provide an 8400 hour guarantee! 43
Bicarmill Smart Mill - Bicarmill - The Complete Package Housing all of the necessary components into a single, pre-engineered compact system, the Bicarmill is the guaranteed solution to on-site milling of sodium sorbent, all at a price that is much lower than the combined components of any mill on the market today. Total cost of a complete 1000 kg/h Bicarmill system: $189,000 including an 8400 hour continuous operation guarantee! 44
Bicarmill Smart Mill Features Maintainability - Designed for ease of maintenance Auto-lubrication - Lubricates on-line to ensure long bearing life Build-up Control - Exclusive glycol additive ensures a clean machine Remote Telemetry - Signals before critical failures occur Particle Size Guarantee - Integrated controller guarantees the optimum particle size Weather Enclosure - Fully enclosed machine protects vital equipment Chemical Integrity - Optimal chemistry is maintained for maximum efficiency 45
Bicarmill Smart Mill Features Smart Mill - Controls every function of the milling, dosing and transport circuit Cool Operation - Mill design has little turbulence, and therefore cool operation Maintenance Provisions - Enclosure fitted with maintenance I-beams for part removal Negative Pressure Operation - No messy dust emissions from milling system Air Flow Control - Ensures proper airflow and provides early fault detection Vibration Control - Ensures proper mill operation by modifying glycol injection rate Air Temperature Control - Ensures proper temperature and provides corrective action 46
+ Bicarmill Smart Mill STM Bicarmill Controller Feeder Fan/blower Sorbent Injection + + Mill Classifier The STM Bicarmill smart milling system is a complete package, ready to set down for two-wire installation, one power and one control signal - pre-engineered, pre-wired, pre-programmed, preinstalled - a single, integrated milling solution, guaranteed to operate for a minimum of 8400 hours! 47
Bicarmill Smart Hammermill Negative Pressure and Heat / Build-up Control Newest generation, integrated hammer mill No shroud baffle assembly - negative pressure Has its own circuit for rejects to return to mill hammers No turbulence to create excess heat Dynamic classifier Better control over particle size distribution D97 particle size ±10-15 µm No material build up No heat build-up makes it desirable for milling sodium 48
STM Smart Mill Technology Enclosed Smart Mill with 8400 Hour Uptime Guarantee Classifying mill coupled to a transport air fan, complete with controller for all functions of a milling circuit. Is able to guarantee online operation without stopping for a minimum of 8400 hours. Main features of a smart mill: Packaged machine with controller Low noise emissions Automatic operation - on-board instrumentation Low maintenance - all external access High reliability and quality Alarming features BicarMill Smart Mill 49
Technical Data Bicarmill Equipment Specifications and Capacity Model Installed Power Absorbed Power Acid Gas GUARANTEED Particle Size Capacity* Air Flow Pressure Noise Rotor Size kw kw Type Range µm Range kg/h m 3 /h mm H2O dba 300 18.4 16.6 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 10-250 10-150 800 500 <75 400 29.2 26.3 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 40-450 30-300 1500 800 <75 630 64.2 57.8 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 80-1000 60-600 2700 800 <75 800 98.0 88.2 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 100-1400 70-900 4700 1000 <75 1000 129.0 116.1 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 100-1800 70-1200 6000 1000 <75 1250 205.0 188.7 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 120-3000 80-2000 9750 1000 <75 1500 284.0 261.2 HCl SO2 d90<30µm - d50<10µm d90<20µm - d50<5µm 150-4200 100-2800 13500 1000 <75 *Capacities Stated for Sodium Bicarbonate at GUARANTEED particle size distribution 50
Features of a Smart Mill Smart Bicarbonate Hammermill Functions Temperature control - unreacted particle Airflow control - temperature control Dosing control - accurate dosing rate Classifier control - guaranteed particle size Auto-glycol injection - build-up control Auto-greasing Operation Built-in Airflow Sensor Built-in Vibration Sensor Built-in Temperature Sensor 51
Smart Hammermill The Guts Full-feature classifying mill coupled to a negative pressure transport air fan. Operational features: High energy efficiency Low noise emissions Minimal maintenance needs Compact, small space requirement High reliability and quality Ease of maintenance Basic Smart Mill Mechanical Components 52
Smart Mill Schematic Integrated feeding and milling 53
Smart Mill Airflow Schematic Ambient Air Negative Pressure Sorbent Propulsion Integrated Feeder Mill Exhaust 54
Smart Mill Mill internals w/pneumatic Cylinder Removal Assist 55
BicarMill 630 Smart Mill with Automatic Control System 56
Smart Mill Internal View of Doser and Mill with Pneumatic Open Assist 57
Smart Mill Internal View of Doser and Mill with Hoist Assembly Full yearly programmed maintenance requires approximately 2 hours for complete replacement of all wear parts. 58
Smart Mill Rotor Disc Removal with Hoist Assembly 59
Smart Mill Indirect Injection Smart Mill with Multiple Dosing Units A - Dosing System B - Mill C - Filter/Reciever D - Suction Fan E - Rotary Valve F - Double Dosing System G - Eductor Venturi H - Regenerative Blower I - Mill to Filter Duct L - Filter to Fan Duct M - Air Recycle Loop N - Injection Point Piping 60
Smart Mill Installation Typical Installation on Dry Sorbent Injection System 61
Experience is our Technology Gas Cooling, Milling & Dosing Technologies for the Environment STM EcoSystems 83 Princeton Ave., Suite 3D Hopewell, NJ 08525 Sales Contact: Joe Riley Tel. 609.273.3331 info@stmecosystems.com www.stmecosystems.com Experience is our Technology 62