In some states where coal is in abundant supply, the coal is the primary raw material used to produce electricity. The process of generating electricity occurs in several stages:
- Coal is burned in a large boiler to make high-pressure, high-temperature steam.
- The steam is passed through a turbine.
- The turbine converts the thermal energy in the steam to mechanical energy.
- The spinning turbine then drives the generator to produce electricity.
During the course of power generation with coal, pollutants are emitted into the atmosphere. The three main pollutants that are emitted into the atmosphere that can be detrimental to the environment are nitrogen oxides, sulfur dioxide, and particulates. Specialized equipment is typically used at different points throughout the steam generation process to minimize emissions from the power plant:
- The first step in reducing emissions occurs by utilizing a low nitrogen oxides (NOx) burner to burn the coal. The equipment regulates the rate of combustion of the coal by controlling the amount of air available at different elevations within the boiler to complete the combustion. This process adjustment results in lower NOx emissions.
- In the second step, the flue gas is passed through an electrostatic precipitator (ESP) after it exits the boiler. In the ESP, a series of positively charged collection plates remove negatively charged particulate matter from the flue gas. The ESP captures more than 99 percent of the particulate matter in the flue gas.
- For the third step, a scrubber is used to control the sulfur dioxide compound in the flue gas. These are water-soluble compounds in the emissions. As the flue gas passes through the scrubber, it is mixed with limestone slurry in water. The limestone reacts with the flue gas and absorbs the sulfur dioxide in the flue gas.
Discuss additional current technologies for emission controls for coal-fired electricity generation facilities. Are the above emission control devices enough? Are there other cost-effective process changes or raw material processing operations that can either add to, or have the same effect as, reducing pollutant emissions from these types of plants? What additional clean coal technology (before, during, and after the combustion process) can be considered or used to further reduce emissions? Are carbon capture and storage technologies available for coal-fired plants? Discuss the economic feasibility and the overall benefit, if any, of adding these technologies.
Your response should be in APA format including a title page and a reference page. An abstract is not required for this assignment. The body of your paper (not including title or reference page) should be approximately 2-3 pages.