Fuels In The Cement Industry: Complete Technical Guide

The cement kiln is a machine of fire: the raw meal becomes clinker at the 1,450 degrees and the heat that makes this happen comes from the fuel: the coal, the petcoke, the gas, the oil and, increasingly, the wastes of the society: the fuels of the cement industry decide the largest part of the production cost after the raw materials, shape the flame of the kiln and increasingly determine the environmental balance of the plant: the fuel strategy is the strategy of the whole plant.

The Complete Cement Technical Package (931 files including the books, the courses, the Excel tools and the presentations: $249.99 one-time: instant download through the PayPal payment) includes this fuels file with its combustion tables, the fuel comparisons and the operating guidance of the burners: this article walks the file: the thermal balance, the conventional fuels, the alternative fuels, the combustion in the kiln and the emissions: the reader leaves with the complete fuel picture of his plant.

The fuel of the cement plant is not only the energy: it is also the chemistry: the ash enters the clinker, the sulfur enters the kiln gases, the flame shape enters the burning zone: this page follows the document and the engineer of the package can open the PDF and walk the chapters with this article.

1. The Thermal Energy: The Appetite of the Kiln

The file opens with the scale of the fuel consumption of the cement process:

• The specific heat consumption: the modern dry process kiln with the five-stage preheater consumes the 3,000 to 3,600 megajoules per tonne of the clinker: the older processes the more: the appetite of the line;
• The exchange rate: the 3,200 megajoules per tonne correspond to roughly the 110 to 130 kilograms of the coal per tonne of the clinker: the calendar of the fuel buying;
• The cost share: the fuel is the second largest cost of the cement production after the raw materials, and in the energy markets it can exceed them: the fuel bill of the plant, the budget fought daily;
• The thermal balance: the heat enters with the fuel and the hot air: the heat leaves with the clinker, the exhaust gas and the radiation: the balance of the kiln: the losses of the process, the targets of the audits;
• The trends: the specific heat consumption fell in the last decades with the preheater stages, the calciners and the modern coolers: the 3,000 to 3,200 megajoules of the best modern lines: the progress of the industry;

The appetite of the kiln is the frame of the whole fuel discussion: the file sets the numbers first so every comparison that follows carries the context: the megajoules per tonne of the clinker: the currency of the fuel engineer: the process, measured by its heat.

2. The Coal: The Classical Fuel of the Kiln

The coal is the traditional fuel of the cement industry and the file opens the fuel family with it:

• The hard coal: the carbonaceous rock of the mines: the net calorific value of the 25 to 30 megajoules per kilogram: the volatile matter of the 20 to 40 percent: the standard fuel of the classical plants;
• The lignite and the soft coals: the moist brown coals of the deposits: the calorific value as low as the 8 to 15 MJ/kg: the high moisture requires the heavy drying: the local fuels of the regions;
• The coal grinding: the coal mill grinds the fuel to the 1 to 3 percent residue on the 90 micrometer screen: the pulverized coal burns like the gas: the fineness of the combustion;
• The ash involvement: the coal ash enters the clinker chemistry: the ash content of the 5 to 15 percent: the ash dosing complicates the raw mix: the fuel and the meal intertwine;
• The sulfur of the coal: the sulfur of the fuel contributes to the sulfate cycles and the emissions: the coal selection balances the price and the process: the coal quality of the plant;

The coal profile of the file teaches the plant to read its own fuel: the calorific value, the volatile matter and the ash: the three numbers of every coal delivery: the file gives the analytical methods and the acceptance tables: the coal of the plant, understood at the gate. The moisture of the delivered coal matters equally: the wet coal steals the drying capacity of the coal mill and lowers the combustion temperature of the flame: the typical moisture of the coal for the pulverized firing stays below the 10 percent: the file includes the sampling protocol of the deliveries so the buyer and the supplier share the same numbers: the laboratory of the gate is the first referee of the fuel contract.

3. The Petcoke: The Refinery Residue

The delayed coker and the refinery catalyzers produce the petcoke, the fuel of many modern plants:

• The characteristics: the petcoke burns at the 33 to 35 MJ/kg: the volatile matter of the 8 to 12 percent: the hard fuel of the slow ignition: the burnable but the stubborn;
• The sulfur: the petcoke carries the 3 to 7 percent of the sulfur: the sulfur dioxide of the kiln gas and the condensation cycles: the impact on the SO3 of the clinker: the process price of the cheap fuel;
• The grinding: the petcoke grinds harder than the coal: the special coal mills and the drier burners: the very fine: the 1 to 3 percent residue: the vertical mill of the petcoke: the drying of the low moisture;
• The ignition: the petcoke ignites at the higher temperature: the co-firing with the coal and the high flame temperatures of the modern burners: the combustion management: the volatile matter of the mixture;
• The economy: the petcoke was historically cheaper than the coal per unit of energy: the savings of the fuel budget: the installation requirements and the process penalties: the economic equation of the petcoke;

The petcoke is the fuel of the pragmatists: it burns hard, carries the sulfur and saves the money: the file teaches the plants the full picture: the grinding, the firing and the chloride cycles: the petcoke of the modern kilns: the fuel of the economy at the price of the technology.

4. The Oil and the Natural Gas: The Clean Burners

Not every plant burns the solids: the file covers the liquid and the gaseous fuels:

• The heavy fuel oil: the 40 to 42 MJ/kg of the residual crudes: the atomization at the burner tip: the steam and the air atomizers: the flame of the old burners: the fuel of the coastal plants and the crisis times;
• The light oil and the diesel: the cold start and the flame support: the pilot flames of the kiln: the occasional burning: the simplest fuel of the operation: the stand-by of the industry;
• The natural gas: the 33 to 40 MJ per cubic meter: the clean burning without the ash: the flame control of the burners: the dynamism of the markets: the gas is the fuel of the plants near the pipelines;
• The flame characteristics: the volatile fuels shorten the flames and the liquid fuels lengthen them: the burner settings per the fuel: the shape of the flame and the burning zone: the art of the flame;
• The storage and the safety: the tank farms and the pipelines, the gas pressures and the leak detection: the safety of the volatile: the fire protection of the fuel systems: the emergency plans;

The liquid and the gaseous fuels shine in the flexibility: no ash, no grinding, no storage: but the price of the molecules: the file compares the fuels with the numbers: the engineer of the fuel procurement weighs the stages: the clean burners of the kiln, the flexible instruments of the plant.

5. The Alternative Fuels: The Waste Becomes the Fuel

The modern section of the file: the alternative fuels that transformed the industry:

• The refuse derived fuel: the processed fractions of the municipal and the industrial wastes: the 12 to 20 MJ/kg of the RDF: the sorting, the shredding and the drying plants: the kilns of the substitution rates;
• The tires: the whole and the shredded tires: the 26 to 32 MJ/kg: the steel of the tires adds the iron to the raw mix: the whole tire firing at the kiln inlet: the classic of the alternative:
• The plastics and the SRF: the solid recovered fuel with the Chinese: the 18 to 25 MJ/kg: the chlorine of the PVC watches: the household the industry: the SRF production plants:
• The meat and bone meal: the rendering residues: the 15 to 20 MJ/kg: the phosphates of the fuel enter the clinker: the regulated gain and the emission angles: the nutrient of the alternative menu;
• The solvents and the liquids: the industrial solvents of the chemical plants: the high calorific liquids injected at the burners: the chlorine and the ash checks: the liquid waste burner;

The alternative fuels are the double revolution of the cement: the cost reduction and the waste management: the file teaches the plants the evaluation: the calorific value, the chlorine, the moisture and the logistics: the substitution of the fuel: the progress of the 10 to 50 percent and beyond in the leading plants: the alternative fuels, the fuel of the present. The chlorine deserves the special caution: the chlorides of the PVC plastics disturb the preheater cyclones and the bypass system: the plants cap the chlorine of the fuel blend and analyze every lot: the alternative fueling is a dual profession: the fuel engineer and the environmental engineer in one: the file forms both.

6. The Combustion in the Kiln: The Flame of the 1,800 Degrees

The file explains the combustion space of the kiln where the fuel meets the air:

• The primary air: the transport air of the pulverized fuel: the 8 to 12 percent of the total air: the carrier of the coal and the shaping of the flame at the burner: the primary:
• The secondary air: the hot air from the cooler at the 750 to 1,000 degrees: the main oxygen of the combustion: enters the kiln hood: the heat recovery: the secondary:
• The tertiary air: the air duct to the calciner: the oxygen of the suspension firing: the two-point combustion of the modern plants: the kiln and the calciner share the load: the 60/40;
• The flame temperature: the burning zone at the 1,800 to 2,000 degrees in the flame core: the clinker bed at the 1,450: the temperatures of the combustion:
• The excess air: the oxygen of the kiln gas at the 1.5 to 3 percent: the air balance: the O2 analysis at the tower: the efficiency: the combustion trimmed to the minimum;

The air system is the anatomy of the combustion: the file teaches the fluxes, the temperatures and the control: the modern plant burns in the two points and the engineer reads the whole system: the primary in the kiln, the tertiary in the calciner: the oxygen of the flame, the thermomap of the firing.

7. The Burner: The Pilot of the Flame

The burner is the instrument of the fuel and the file dedicates the chapters to the modern machines:

• The multi-channel burners: the kiln burners with the central fuel and the annular air channels: the swirl, the axial and the radial airs: the flame shape control: the tools of the modern firing:
• The momentum: the kinetic energy of the burner jet: the momentum of the flame: the long or the short flame per the process: the retention of the gases: the momentum of the petcoke and the alternative fuels process;
• The coal injection: the transport of the pulverized coal: the carrier air: the velocities of the 20 to 40 meters per second: the coal firing: the maintenance of the nozzles:
• The swirl: the tangential air: the recirculation of the combustion gases: the igniting the fuel at the muzzle: the swirl adjustment per the fuels: the aerodynamics of the flame:
• The flame cameras: the CCD cameras of the burning zone: the flame image analysis: the luminous patterns: the fire, watched: the instrument of the operator:

The burner is the last ladder of the fuel and the file: the burner settings per fuel: the momentum, the swirl and the positioning: the plants that change the fuels change the burner — the file makes the engineers the masters of the flame: the flame of the plant, controlled.

8. The NOx and the Combustion: The Emissions of the Fire

The combustion has the unwanted children and the file explains the emissions of the firing:

• The thermal NOx: the nitrogen oxides of the high flame temperatures: the 900 to 1,500 milligrams per normal cubic meter from the kiln flame: the limit values of the permits: the burning:
• The reduction: the staged combustion, the low-NOx burners, the SNCR ammonia injection: the 50 to 70 percent reductions: the cooled flames: the nitrogen of the air and the fuel:
• The fuel NOx: the nitrogen of the coal and the alternative fuels: the bonds: the control of the fuel: the concentration of the fuel in the flame:
• The CO control: the incomplete combustion: the carbon monoxide in the gases: the dryer of the kiln: the CO monitoring at the baghouse: the safety of the explosive mixtures:
• The particulate and the metals: the dust of the combustion and the trace metals of the fuels: the filters capture and the environment: the metals: the alternative fuels toxin:

The emissions of the fire are the license to operate: the file maps the pollutants, the reduction technologies and the measurement: the plant that knows its NOx knows its future permits: the combustion of the kiln: the environment statement of the plant: the fire, responsible.

9. The Sulfur Cycle: The Fuel and the Chemistry

The sulfur of the fuels circulates through the kiln and the file explains the cycle:

• The sulfur sources: the fuel sulfur, the raw material sulfur: the pyrite and the sulfates of the rocks: the total sulfuric units of the kiln feed and the fuel:
• The volatilization: in the burning zone the sulfur compounds evaporate: the alkali sulfates circulate in the preheater: the condensation and the re-entry: the internal cycle of the bypass:
• The blockages: the excessive sulfur alkalis condense at the riser ducts: the blockages and the material buildups: the chlorine surgical: the SEM requires: the blockages of the cyclones:
• The SO2 emissions: the sulfur dioxide from the fuel and the meal: the controlled at the kiln: the SO2 emission measurements: the target: the raw sulfur peaks in the preheater:
• The clinker sulfates: the incorporating sulfur in the clinker SO3: the cement chemistry: the gypsum the complement: the sulfur of the fuel, the sulfate of the cement:

The sulfur is the chemistry of the fuel: the file teaches the cycle so the plants understand the buildups and the clinker: the fuel bill enters the quality report of the cement: the sulfur and the alkali of the kiln: the internal process: the file: the cycle of the fire, documented.

10. The Fuel Storage and the Handling: The Logistics of the Fire

The fuel arrives, stores and fires: the file presents the logistics of the fuel yard:

• The coal yard: the allocated stockpiles: the coal: the stacking, the reclaimers and the homogenisation through the layering: the calorific blend of the fuel: the handling: the dust control:
• The pulverized coal storage: the silos after the milling: the inert gas fire safeguards: the pneumatic distribution: the coal fired: the flows: the coal line of the burner:
• The petcoke management: the petcoke storage: the dusty handling: the dust collection and the spillage: the degradation of the volatiles: the sale of the petcoke: the fuel: the easy:
• The liquid fuels: the tank farm, the heated tanks for the heavy oil: the fuel pumps: the temperatures: the viscosity: the liquid lines to the kiln burner: the fuel oil of the liquid lines:
• The alternative fuel lines: the reception, the quality control and the conditioning: the dosing: the feeders: the whole tires and the shredded: the fuel feeding of the calciner: the security of the waste: the quality check of the feeding:

The fuel handling is the discipline of the fire: the file teaches the yard layout, the stock management and the safety: the plants that manage the fuel manage the cost: the fire of the kiln begins in the yard: the fuel logistics, engineered: the handling of the fire, the file.

11. The Alternative Fuel Preparation: The Factories of the Waste

The alternative fuels arrive prepared and the file covers the preparation plants:

• The sorting: the incoming selection: the ferrous, the non-ferrous and the inert: the magnets and the eddy currents: the contaminants removed: the fuel: the combustibles: the sorting:
• The shredding: the shredders at the two stages: the one-stage 300 to 500 millimetres, the final at the 80 to 150: the size distribution of the fuel: the qualification of the combustion:
• The drying: the waste moisture: the 15 to 40 percent: the biological drying: the greenhouse drying: the kiln dryer: the moisture of the solid recovered fuel: the value lost:
• The segregation: the metals and the chlorines: the PVC: the test benches: the sampling of the produced SRF: the quality declaration: the feed composition: the plant: the fuel:
• The storage: the bunkers and the silos: the fire detection in the fuel warehouses: the heat and the vapors: the extinguishing systems: the safe storage of the fire: the safety:

The preparation is the front end of the alternative fuel economy: the file teaches the flowsheet of the SRF plants: the shredders, the magnets and the dryers: the quality control of the waste fuel: the cement kiln is the final recipient: the preparation, engineered: the fuel of the waste, tamed.

12. The Fuel Strategy of the Plant: The Economic Framework

The business chapters of the file frame the fuel as the strategic decision:

• The energy mix: the portfolio of the fuels: the coal base, the petcoke discount, the alternatives: the ratio per the year: the supply contracts of the plant: the mixing plan: the strategy:
• The substitution rate: the share of the thermal energy from the alternative fuels: the leading plants above the 50 to 80 percent: the CO2 deduction of the landfill: the double credit:
• The energy cost: the dollar per ton of the clinker: the fuel cost / the thermal ratio: the benchmark: the exchange of the audit: the monthly: the cost line of the plant:
• The supply security: the multiple suppliers: the regional fuels: the strike and the weather: the buffers: the flexibility of the plant: the supply: the continuity:
• The emissions allowances: the CO2 certificates in the emissions trading: the fuel carbon content: the alternative shares: the certificates: the cost of the carbon: the fuel economy of the emissions:

The fuel decision is the boardroom decision: the file translates the technology into the economics: the tons, the certificate prices and the substitution rates: the engineer: the purchasing: the TCO: the fuel economy of the plant: the file teaches the strategic thinking of the fuel. The monthly fuel report of the file contains the delivered energies per fuel, the realized substitution rates and the costs per tonne of clinker: the report becomes the bridge between the process floor and the management table: the numbers of the file: the complete picture of the thermal economy: the strategy of the fire, decided with the measured data.

13. The Operations of the Fuel Change: The Daily Switch

The file’s the operations: the change of the fuels on the running kiln:

• The warm switch: the switch from the gas to the coal: the burner pressure, the air and the flame: the monitored: minutes: the transition of the process: the permanent: the switch: the daily:
• The commissioning: the new fuel: the trials: the sampling: the adjustment of the burner: the test phases: the trials of the process: the acceptance: the fuel: the angles:
• The instability: the fuel variations: the variations of the flame: the operations: the kiln and the quality: the reaction of the operators: the corrections: the automated control:
• The emergencies: the fuel interruptions: the failure: the answer: the heavy oil support: the gas support: the fallback: the emergency of the fuel: the plan:
• The record: the fuel logs: the energies and the rates: the analysis reports: the monthly: the statistics of the fuels: the fuel accounting of the plant:

The operations chapter of the file teaches the change management: the plant that burns the multiple fuels runs the change sequences smoothly: the temperature, the oxygen and the flame watch: the operator’s the crafts: the file: the switch, planned: the daily fuel, the continuous change: the ops of the fire, methodical.

14. The Emissions and the Environment: The Fire Within the Law

The file closes the industrial chapters with the complete environmental frame:

• The emission limits: the dust: the 10 to 30 mg/Nm3: the NOx: the 200 to 500: the SO2: the 50 to 400: the law of the permits: the continuous emission measurements of the stacks: the reporting:
• The mercury and the metals: the traces of the fuels: the mercury monitor: the emission guarantees: the control room: the mercury, the fuel matter: the environment:
• The dioxin management: the combustion of the chloride wastes: the dioxins and the furans: the temperature and the abatement: the lime injection: the monitoring: the dioxin monitoring: the abatement proven: the file.
• The CO2: the process and the fuel: the total CO2 of the cement: the calcination 50 percent and the fuel 40 percent: the 800 kg per tonne of the clinker: the destiny of the cement: the energy transition of the industry:
• The future fuels: the hydrogen and the electrified calcining: the O2 enriched: the projects: research: the century: the cement plant of the future: the fire: the low-carbon puzzle of the transition: the file:

The fuels and the environment are the same chapter: the file teaches the limits, the measurements and the strategies of the low-carbon future: the fire of the kiln must become the green: the alternative and the process decarbonization: the cement of the future: the file brings the industry’s technology to the table: the fuel: the environment, one picture.

15. Conclusion

The fuels of the cement industry: the coal, the petcoke, the oil, the gas and the waste of the society: the family of the fire that feeds the 1,450 degrees of the clinker: the file of the package teaches the totality: the thermal balance, the fuel profiles, the combustion, the burners, the emissions and the strategy: the engineer who reads the file reads the flame of his plant with the new eyes: the fuel is the energy, the chemistry and the environment of the kiln: the fuel strategy of the plant, mastered: the fire, understood.

The Complete Cement Technical Package includes this fuels file with the combustion tables, the fuel comparisons and the economics of the substitutions: the one-time $249.99: the instant download: the library of the cement: the file of the fire: the engineer of the package: the kiln, fed right: the fuel bill, optimized: the knowledge of the combustion, the professional.

The Frequently Asked Questions

What is the typical heat consumption of the modern kiln?

The modern dry process kiln with the cyclone preheater and the calciner consumes about the 3,000 to 3,600 MJ per tonne of the clinker: the older the wet and the long dry processes consume more, up to the 5,000 to 6,000: the file compares the processes so the engineer measures his own plant against the modern reference and targets the audit savings.

Why do the alternative fuels keep growing in the industry?

Two logics: the economy and the environment: the waste-based fuels are often cheaper than the fossil thermal energy and they relieve the landfill problem of the society: many plants substitute the 50 to 80 percent of their heat with the alternatives: the kiln: the temperature and the retention destroy the organics: the double win of the fuel: the file shows both sides.

The petcoke and the sulfur: the problem is real?

Real: the petcoke commonly carries the 3 to 7 percent of the sulfur, far above the oil: the kiln cycles the sulfur through the preheater and the bypass systems must manage the volatiles: the plants that burn the petcoke master the sulfur cycle: the file covers the cycle: the emissions and the clinker sulfates together with the price advantage.

Which is the best fuel for the cement kiln?

There is no absolute: the best fuel is the cheapest per unit of the delivered energy after the process: the coal: the most flexible: the petcoke the cheapest and the sulfur: the gas the clean: the alternatives the cheapest in the regions: the file teaches the evaluation matrix: the calorific value, the ash, the chlorine, the logistics and the emissions: the best fuel: the plant’s local optimal.

The file includes the burner settings of the fuels?

The document gives the combustion principles, the flame characteristics and the burner adjustments per fuel family: the multichannel settings: the swirl and momentum: the staged combustion: the working examples: the burner tuning is practiced at the plant with the engineering and the experience: the file: the guide: the operator: the flame: the continuous.

Does the package include the Excel of the fuel economics?

The fuel comparison calculator is among the 931 files of the package: the engineer enters the prices, the calorific values and the substitution shares and receives the cost per tonne of the clinker and the carbon: the same library that carries this fuel guide: the economics of the fire, spreadsheet: the tool of the fuel decisions.

This file is part of the Complete Cement Technical Package (931 files) available from cementequipment.org. Respective rights holders; library copy for the licensed single user.