Waste-to-Energy Industry B&W Volund

Waste to Energy
for a Sustainable, Circular Economy

B&W Renewable

What is Waste to Energy?

Ecologically Sound, Cost-Effective Energy

Waste to energy (WtE) is a vital part of a strong and sustainable waste management chain. Fully complementary to recycling, it is an economically and ecologically sound way to provide a renewable source for energy while diverting waste from landfills. 

 

  

How Does Waste to Energy Work?

A WtE plant converts solid waste into electricity and/or heat - an ecological, cost-effective way of energy recovery.
 
A waste-to-energy (or energy-from-waste) plant converts municipal and industrial solid waste into electricity and/or heat for industrial processing and for district heating systems – an ecologically sound, cost-effective means of energy recovery. The energy plant works by burning waste at high temperatures and using the heat to make steam. The steam then drives a turbine that creates electricity.

Recover valuable resources
 
Energy from waste (EfW) isn’t just a trash disposal method. It’s a way to recover valuable resources.

Today, it is possible to reuse 90% of the metals contained in the bottom ash. And the remaining clinker can be reused as road material. 

The results and benefits are proven:

  • Avoids methane emissions from landfills
  • Offsets greenhouse gas (GHG) emissions from fossil fuel electrical production
  • Recovers/recycles valuable resources, such as metals
  • Produces clean, reliable base-loaded energy and steam
  • Uses less land per megawatt than other renewable energy sources
  • Sustainable and steady renewable fuel source (compared to wind and solar)
  • Destroys chemical waste / conventional HAPs
  • Results in low emission levels, typically well below permitted levels
  • Catalytically destroys NOx, dioxins and furans using an SCR


High efficiency and low emissions

Waste to energy is one of the most robust and effective alternative energy options to reduce CO2 emissions and replace fossil fuels.

Approximately 2/3 of household waste is categorized as biomass. Therefore, we can recover 2/3 as CO2-neutral energy and reduce our dependence on fossil fuels.

In Europe, 50 million tons of waste is converted into valuable energy through WtE technology, supplying 27 million Europeans with electricity. Still, 50% of municipal solid waste becomes landfill. This releases greenhouse gasses like methane which is more than 20 times more powerful than CO2. Our WtE technology eliminates these emissions.

Our goals are two-fold: to maximize production and efficiency to meet energy needs, and to reduce our environmental footprint. 

Waste facts

  • 4 tons of waste equals 1 ton of oil
  • 2 tons of waste equals 1 ton of coal

How Can WTE Be Part of Our Circular Economy

Did You Know?

As urbanization and spending on consumables increases, more solid waste is generated. The amount of solid waste has grown over the last century to more than 3 million tons now generated per day globally, and the number is expected to double by 2025 (Organization for Economic Cooperation and Development).

Solid waste management is often one of the greatest costs to municipal budgets. Increasing the amount of municipal solid waste in landfills translates to increases in greenhouse gas (GHG) emissions, air and odor pollution, and soil and water contamination.

Sustainable waste management

To reduce the size, cost and environmental impacts of landfills, many regions are shifting from a linear economy (make-use-dispose) to a more circular economy model, where materials are made, used and reused to their fullest extent. Complementary to recycling, WtE plants extend the useful life of the solid waste, converting it into electricity and/or heat for industrial processing and district heating systems, filtering out harmful substances and recovering metals and other material for reuse. WtE is one of the most robust and effective energy options to produce power while treating waste and reducing emissions as an alternative to fossil fuels.

 

How waste to energy works

Waste to energy is one of the most robust and effective alternative energy options to reduce CO2 emissions and replace fossil fuels.

Waste-to-Energy Technologies

Mass-Burn or Refuse-Derived Fuel (RDF)

B&W provides two boiler options when using waste as a combustion fuel. Mass burning municipal solid waste uses the refuse in its as-received, unprepared state. The second technique uses prepared refuse, or refuse-derived fuel (RDF), where the as-received refuse is first separated, classified and reclaimed in various ways to yield salable or otherwise recyclable products. The remaining material is prepared for firing in the boiler.

Boiler Designs

Mass burning is the most common refuse combustion technology worldwide. Three major designs are used in modern mass burn power plants: 1) single-pass furnace, 2) multi-pass furnace with vertical convection pass, and 3) multi-pass furnace with a horizontal convection pass.

B&W has proven experience with designing and building all three variations, with the choice of design determined by the application. All three designs feature a furnace that is strategically arranged over the grate to control gas flow and maximize heat absorption, and thus, maximize efficiency. B&W designs the flue gas flow path to provide reasonably uniform cross-section flow and temperature distributions by using physical and/or numerical computational fluid dynamics (CFD) modeling, and empirical data. A short summary of each follows:

Single Pass Furnace

B&W’s single-pass furnace is a top-supported design that features a single vertical shaft for the rising combustion gases from the grate, with enough residence time and temperature to burn the fuel completely and cool the flue gas to the required furnace exit gas temperature before entering the superheater. The flue gas then turns 90 degrees around a furnace arch to pass through the horizontal crossflow top-supported superheater before turning downward to flow through the longflow steam generating bank. The flue gas then passes vertically over the crossflow economizer and exits the boiler enclosure.

Multiple Pass Furnace with Vertical Convection Pass

B&W’s multipass furnace with vertical convection pass locates the steam generating bank and superheater in the vertical third pass, and the economizer in the fourth pass. In this design, furnace gases pass upwards through the radiative section then makes a 180-degree turn and flows downward through a second vertical radiation pass. The gas then makes another 180-degree turn and flows up through the third pass where the superheater and generating bank are located. Finally, the flue gas is directed downward through the fourth pass which contains the crossflow economizer. While this design minimizes the larger footprint of the three-pass furnace, accessing the superheater in the vertical gas path for maintenance is more difficult.

Multiple Pass Furnace with Horizontal Convection Pass

The combustion gases of B&W’s multipass furnace with horizontal convection pass leave the grate and lower furnace and pass upward through the first open furnace pass and then downward through the second open pass. A portion of the first pass may be covered with specialized materials to reduce heat absorption and permit the flue gas to maintain a suitable temperature for complete combustion of the fuel in smaller boilers, and at lower loads in larger units. At the bottom of the second open pass, the flue gas turns 180 degrees to pass upward through the third pass to cool the flue gas to the required gas temperature before entering the horizontal convection pass.


Combustion Grates 

B&W combustion grates provide waste flow that ensures drying, ignition, combustion, energy release and complete burn-out before the bottom ash outlet.

In a waste-to-energy plant, the grate is where waste is converted into energy – the heart of the system. As such, grates are a significant focus area for us. Over the past 80 years we have supplied more than 500 combustion grates worldwide. Many of our older grates are still in operation, running efficiently and living up to current environmental standards.

B&W offers two combustion grates: the DynaGrate® technology and Vølund combustion grates. Each grate is available in both water-cooled and air-cooled designs. The DynaGrate and the Vølund grates were developed to provide reliable transport of waste through the furnace.


WASTE-TO-ENERGY TECHNOLOGIES

Combustion Grates & Stokers

Combustion Grate
In a waste-to-energy plant, the grate is where waste is converted into energy – the heart of the system. Over the past 80 years we have supplied more than 500 combustion grates worldwide. 

Waste Fuel Feeder Systems

Fuel Feeding Systems
Steady and continuous feeding of fuel in waste-to-energy plants is the key to stable operation, maximum efficiency, and lower operational and maintenance costs.

Water-Cooled Wear Zones

Water-Cooled Wear Zones
Water-cooled wear zones are a revolutionary, efficient, and economical way to improve operational accessibility and productivity for waste-fired power plants.

Energy   Recovery

L90 Waste-to-Energy Plant
Improved revenue and reduced greenhouse emissions are benefits that come from extended energy recovery by condensation of the hot flue gases.

VoluMixTM Systems

VoluMix
Proper turbulent mixing of the flue gases in the boiler furnace provides a better combustion process and burn-out in the gas phase.

Emissions  Control

SCR System for NOx Reduction
As a single-source supplier, we can develop an integrated multi-pollutant strategy to match your long-term requirements.  Through every phase of the project, we take time to determine your needs and recommend a customized solution.

Flue Gas Treatment

Flue gas cleaning
Our flue gas cleaning systems are purpose-designed to treat the gas so emission limits meet acceptable margins during fluctuations in the gas composition.

Corrosion Protection

Corrosion Protection
At our production facility in Denmark, capabilities such as spiral welding and cold metal transfer welding allow us to design and manufacture boiler tubes and wall panels that can withstand the special operating conditions of WTE applications.


PROJECTS & CASES

ARC, Copenhill

B&W Volund Copenhill Waste-to-Energy Plant

DENMARK

Located in Copenhagen, Copenhill / Amager Bakke sets new standards for environmental performance, energy production and waste treatment.

Video: The Story of Copenhill

 

SWA, Palm Beach 2

Palm Beach WtE Facility 2 Babcock & Wilcox

USA

In partnership with BE&K, B&W engineered, designed, procured and constructed SWA's Palm Beach Renewable Energy Facility No. 2. - one of the largest WtE facilities in the world. And through our subsidiary, we are providing O&M services.

Video: One of the largest WtE facilities in the world

 

Indaver, County Meath

B&W waste-to-energy plant in Ireland

IRELAND

For the first time in Ireland's history, in 2011 20,000 households in Meath County are provided with waste-powered electricity.    

Video: Virtual Plant Tour

 

RESOURCES & SELF STUDY

Clean Power From Burning Trash

Mechanical Engineering WtE cover

Did you know that there is a clean alternative to landfills?

Sustainable, Clean Energy from Waste

Sustainable Waste Brochure

A proven technology with measureable results.

New Build

Palm Beach Renewable Energy Facility

Each waste-to-energy plant has a unique profile and achieving full potential requires a tailor-made business model. B&W can work with you to create the best model built on our proven technology.

Aftermarket Support

B&W Aftermarket Support

Our specialists provide a wide range of services, improvements and upgrades to support useful lifetime of a waste-to-energy, biomass, multi-fuel or fossil fuel-fired plant.

Environmental Systems 

SCR Systems

Whatever your environmental solution requirements, however complex they may be, our engineers will work to find the right solution.