Waste, solid types

Hearth incinerators. This type of incinerator is designed primarily to incinerate solid waste. Solids are moved through the combustion chamber mechanically using a rake. 

It is the roughly 7 percent of solid wastes produced by industrial and energy-generation operations and the 3 percent produced by nonindustrial human activities that present the most serious environmental problems in the United States today. These fall into three large categories (1) pure volume of wastes, (2) hazardous wastes, and (3) radioactive wastes. Each type of solid waste poses its own set of problems and requires its own set of solutions. 

Containers for conventional wastes. The types and capacities of containers now commonly used for on-site storage of solid wastes are summarized in Table 22-62. The small containers are used in individual offices and workstations. The medium-size and large containers are used at locations where large volumes are generated. 

Containers for conventional wastes. The types and capacities of containers now commonly used for on-site storage of solid wastes... 

Rather than carry out liquid-liquid extractions, which are time-consuming and lead to large quantities of waste, solid supports can be constructed that have high affinity for selected types of molecules. Simple filtration of a solution through a column of the solid-phase medium results in efficient extraction of the product. This method is quite widely used and is of particular interest for fluorous chemistry (see below). 

Limestone (CaCC>3) dissolution is an important phenomenon in stack gas desulfurization processes using limestone slurry to absorb SC>2 and produce CaSC>3/CaS04 waste solids (1). The rate of dissolution directly determines the need for excess limestone and interacts strongly with SC>2 removal and scale-free operation in the absorber. There is a need to know the dependence of dissolution rates on both solution composition and the type and grind of limestone. This paper presents a mass transfer model and... 

Figure 13.2 Components of municipal solid waste and types of packaging waste by weight (redrawn from data in ref. [4]).

Sohd wastes, as noted previously, include all sohd or semisolid materials that are no longer considered of sufficient value to be retained in a given setting. The types and sources of solid wastes, the physical and chemical composition of sohd wastes, and typical solid-waste generation rates are considered in this subsection. 

Types of Solid Wastes The term solid wastes is aU-inchisive and encompasses all sources, types of classifications, compositions, and properties. As a basis for subsequent discussions, it will be helpful to define the various types of solid wastes that are generated. It is important to note that the definitions of solid-waste terms and the classifications vary greatly in prac tice and in literature. Consequently, the use of published data requires considerable care, judgment, and common sense. The following definitions are intended to serve as a guide. 

Conventional Wastes Sources and types of industrial solid wastes generated by Standard Industrial Classification (SIC) group classification are reported in Table 25-49. The expected specific wastes in the table are those that are most readily identifiable. 

On-Site Storage Factors that must be considered in the on-site storage of solid wastes include (1) the type of container to be used, (2) the container location, (3) public health and aesthetics, (4) the collection methods to be used, and (5) future transport method. 

Containers To a large extent, the types and capacities of the containers used depend on the characteristics of the solid wastes to be collected, the collection frequency, and the space available for the placement of containers. 

TABLE 25-55 Data on the Types and Sizes of Containers Used for On-Site Storage of Solid Wastes... 

Manual Component Separation The manual separation of solid-waste components can be accomplished at the source where solid wastes are generated, at a transfer station, at a centralized processing station, or at the disposal site. Manual sorting at the source of generation is the most positive way to achieve the recoveiy and reuse of materials. The number and types of components salvaged or sorted (e.g., cardboard and high-quality paper, metals, and wood) depend on the location, the opportunities for recycling, and the resale market. There has been an evolution in the solid waste indus-tiy to combine manual and automatic separation techniques to reduce overall costs and produce a cleaner product, especially for recyclable materials. 

---