Introduction to Solid Waste and Its Management

Solid Waste Production

Solid waste generally refers to unused solid materials generated as a result of human activities. Many of these items can be considered as waste such as domestic rubbish, sewage sludge, wastes from manufacturing activities, packaging items, discarded cars, discarded electronic devices, garden waste, old paint containers etc. Accordingly, all human daily activities can give rise to a large variety of different wastes arising from different sources (Ngoc & Schnitzer, 2009). Based on their sources, solid waste can be classified into various types which include MSW, hazardous waste, agricultural waste and industrial waste (Tchobanoglous et al., 1993). In Malaysia; the generation of MSW has significantly increased in recent years, ranging between 0.5 - 2.5kg per capita per day (or a total of 25000 - 30000 tons per day). More than 70% of the generated wastes are collected using both curbside and communal centers with a collection frequency varying from daily to every two days (Johari et al., 2014).

MSW defined as a waste collected from households, in addition to the commercial waste collected by a municipality but it generally excludes hazardous wastes. Because urbanization and population growth have rapidly increased the rate of MSW production and disposal in many cities of the world, the management of MSW has emerged as a major concern around the world particularly the rapidly developing countries.

According to Tanaka (2006), the generation of solid waste is expected to increase steadily along with economic growth if we continue the lifestyle of mass production, mass consumption and mass disposal (Figure 1).

Figure 1.

Predicted solid waste generation (Tanaka, 2006)

It has been reported by Chong et al. (2005) that solid waste is one of the biggest environmental problems in Malaysia and the generation rate of solid waste is expected to increase tremendously due to the rapid increase in population and economic growth in the country.