Chapter Six - Clean Coal Technology Combustion Products: Properties, Agricultural and Environmental Applications, and Risk Management

Abstract

Coal combustion products (CCPs), as the name suggests, are residues derived from the burning of coal in power generation industries. Traditionally, they have been dumped in large piles and/or ash-ponds mostly around the power stations. The CCPs are generally ash materials, mostly made of fine particles but some are also generated as coarse particles. Generation of these products poses serious threats to air, water and soil, and consequently to living organisms. The extent of the environmental effects caused by CCPs depends on (1) the coal source, (2) the combustion technology used and (3) the collection and segregation of the residues. Over the past two decades, there have been progressive research on the quality of power generation in terms of economic viability and environmental safety, and the effective usage of the waste products generated as a result of the power generation. This resulted in the emergence of clean coal technologies (CCTs), which aim at minimal environmental impacts, especially in curbing air pollution and ensuring more beneficial residues compared to conventional methods of combustion. In the global perspective, CCTs also reduce emission of several pollutants, decrease waste generation and increase the amount of energy gained per unit amount of coal combustion. This chapter will focus on the recent developments in CCTs and the applications of CCPs arising from those technologies, particularly agricultural and environmental applications. This chapter outlines the coal economy, their importance in power generation, latest technologies in the coal-fired power stations addressing emission control, the properties of CCPs generated, applications of CCPs and threats posed by the products. Each section will start with the products of conventional combustion technology (e.g. fly ash) and will later cover the applications pertaining to the products from CCTs (e.g. fluidized bed combustion ash). Future research should aim to focus more on the biological implications of CCPs addition to soil, long-term trials and a repository on ash information.