Waste Conversion: The Benefits of Gasification

As the uses for gasification expand into municipal and hazardous waste conversion, plant operators have the opportunity to conserve resources and limit hazardous emissions.

Savannah Admire

 

With coal-fired power plants releasing potentially hazardous chemicals and threatening the environment, operators around the world seek new ways to generate electricity and other forms of energy. Processes such as gasification provide more environmentally friendly, economically beneficial methods for producing energy.

 

Environmentally and Economically Advantageous

The process of gasification converts organic materials into carbon monoxide, carbon dioxide and hydrogen gas. This process is widely used on industrial scales for the generation of electricity from fossil fuels. A wide variety of biomass and waste-derived feedstock can be gasified, including wood waste, plastics, aluminum, municipal solid waste (MSW), agricultural and industrial wastes, sewage sludge and crop residues.

 

Gasification can potentially process both mixed waste and the plastic-only fraction of waste. The process uses a smaller amount of air, resulting in higher energy recovery efficiency and limited formation of pollutants like nitrogen oxides.

 

The gasification of waste has numerous environmental advantages over incineration and other technologies. Gasification plants produce significantly lower quantities of air pollutants. The process reduces the environmental impact of waste disposal because it allows for the use of waste products as a feedstock. Gasification plants also use less water than traditional coal-based power plants. The by-products of gasification are non-hazardous and readily marketable.

 

Gasification is not only beneficial to the environment, but also economically advantageous. This process can effectively compete in high-price energy environments to provide both power and products. Gasification can be utilized to turn lower-priced feedstock, such as pet coke and coal, into valuable products, like electricity, fuels and fertilizers.

 

The operating costs of a gasification power plant are lower than conventional coal-fired plants and require less pollution control equipment. A gasification plant also offers wide fuel flexibility, as it can vary a mix of solid feedstock or run on a gas or liquid feedstock, allowing the operator more freedom to adjust to the price and availability of various kinds of feedstock.

 

Producing Transportation Fuels and Electricity

Gasification has numerous applications, including agriculture and forestry residues and household and commercial waste, as well as recovering energy from residues left from materials recycling, such as electronic scrap, tires and plastic waste.

 

The gasification process can be used to produce methanol and chemicals like ammonia and urea, which are the foundation of many fertilizers. Gasification can also be used to produce transportation fuels from oil sands, coal and biomass.

 

Waste gasification can be used to enhance recycling programs. One ton of MSW can produce up to 1,000 kW of electricity. The gasification of waste reduces the need for landfill space, decreases methane emissions and reduces the use of fossil fuels.

 

Similarly, coal gasification provides one of the cleanest and most versatile ways to convert coal into electricity, hydrogen and other valuable energy products. The process breaks down coal into its basic chemical constituents, producing a mix of hydrogen, carbon monoxide and other gaseous compounds. Gasification offers the cleanest, most efficient means of producing electricity from coal and the lowest cost option for capturing carbon dioxide from power generation.

 

Reliable Technology

Gasification has been reliably used on a commercial scale around the world for more than 50 years in the refining, fertilizer and chemical industries. As the uses for gasification expand into municipal and hazardous waste conversion, plant operators have the opportunity to conserve resources and limit hazardous emissions.

 

Savannah Admire is the Writer at Vulcan® Systems (formerly Worldwide Recycling Equipment Sales) and has published articles in more than 20 industry publications. For more information on Vulcan® Systems, call (660) 263-7575, e-mail marketing@vulcansystems.com or visit www. vulcansystems.com.