2 Constituents in Wastewater nd reuse facilities. and in the engineering r nt of environmental qualitv. To promot this understanding, the information in this cho er, (2)sampling and analytical procedures, (3)physical ter is presented in eight sections dealing with(1)an introduction to the constituents found in wastewat characteristics,(4)inorganic nonmetallic constituents, (5) metallic constituents,(6) aggregate organic constituents,(7)individual organic constituents and compounds, and( 8)biological characteristics 2-1 Wastewater Constituents Constituents found in wastewater The principal physical properties and the chemical and biological constituents of wastewater, and their sources,are reported in Tab 2-1. It biological characteristics are interrelated. For example, temperature, a physical property, affects both the amounts of gases dissolved in the wastewater and the biological activity in the wastewater Constituents of concern in wastewater treatment The important constituents of concern in wastewater treatment are listed in Tab 2-2. Secondary treatment standards for wastewater are concerned with the removal of biodegradable organics, total suspended solids and pathogens. Many of the more stringent standards that have been developed recently deal with the removal of nutrients, heavy metals, and priority pollutants. When wastewater is to be reused, standards normally include additional requirements for the removal of refractory organics, heavy metals, and in some cases, dissolved inorganic solids 2-2 Sampling and Analytical Procedures Proper sampling and analytical techniques are of fundamental importance in the characterization of wastewater. Sampling techniques, the methods of analysis, the units of measurement for chemical constituents, and some useful concepts from chemistry are considered below Sampling Sampling programs are undertaken for a variety of reasons such as to obtain(1)routine operating data on overall plant performance,(2)data that can be used to document the perfomance of a given treatment operation or process, (3)data that can be used to implement proposed new programs, and(4)data needed for reporting regulatory compliance. To meet the goals of the sampling program, the data collected must 1. Representative. The data must represent the e wastewater or environment being sampled. 2. Reproducible. The data obtained must be reproducible by others following the same mentation must be available to validate the sampling procedures. The data must have a known degree of accuracy and precision. Useful. The data can be used to meet the obiectives of the monitoring plan. Because the data from the analvsis of the samples will ultimately serve as a basis for implementing wastewater management facilities and programs. the techniques used in a wastewater sampling program must be such that representative samples are obtained. Table 2-1 Common analyses used to assess the constituents found in wastewa Test Abbreviation/ Use or significance of test results definition Total solids determine most suitable type of operations and Total volatile solids processes for its treatment Total fixed solids TFS I suspended solids TSS Volatile suspended solids Fixed suspended solids FSS Total dissolved solids TDS(TS-TSS) VDS2-1 2 Constituents in Wastewater An understanding of the nature of wastewater is essential in the design and operation of collection, treatment, and reuse facilities, and in the engineering management of environmental quality. To promote this understanding, the information in this chapter is presented in eight sections dealing with (1) an introduction to the constituents found in wastewater, (2) sampling and analytical procedures, (3) physical characteristics, (4) inorganic nonmetallic constituents, (5) metallic constituents, (6) aggregate organic constituents, (7) individual organic constituents and compounds,and (8) biological characteristics. 2-1 Wastewater Constituents Constituents Found in Wastewater The principal physical properties and the chemical and biological constituents of wastewater, and their sources, are reported in Tab 2-1. It should be noted that many of the physical properties and chemical and biological characteristics are interrelated. For example, temperature, a physical property, affects both the amounts of gases dissolved in the wastewater and the biological activity in the wastewater. Constituents of Concern in Wastewater Treatment The important constituents of concern in wastewater treatment are listed in Tab 2-2.Secondary treatment standards for wastewater are concerned with the removal of biodegradable organics, total suspended solids, and pathogens. Many of the more stringent standards that have been developed recently deal with the removal of nutrients, heavy metals, and priority pollutants. When wastewater is to be reused, standards normally include additional requirements for the removal of refractory organics, heavy metals, and in some cases, dissolved inorganic solids. 2-2 Sampling and Analytical Procedures Proper sampling and analytical techniques are of fundamental importance in the characterization of wastewater. Sampling techniques, the methods of analysis, the units of measurement for chemical constituents, and some useful concepts from chemistry are considered below. Sampling Sampling programs are undertaken for a variety of reasons such as to obtain (1) routine operating data on overall plant performance, (2) data that can be used to document the performance of a given treatment operation or process, (3) data that can be used to implement proposed new programs, and (4) data needed for reporting regulatory compliance. To meet the goals of the sampling program, the data collected must be: 1. Representative. The data must represent the wastewater or environment being sampled. 2. Reproducible. The data obtained must be reproducible by others following the same sampling and analytical protocols. 3. Defensible. Documentation must be available to validate the sampling procedures. The data must have a known degree of accuracy and precision. 4. Useful. The data can be used to meet the objectives of the monitoring plan. Because the data from the analysis of the samples will ultimately serve as a basis for implementing wastewater management facilities and programs, the techniques used in a wastewater sampling program must be such that representative samples are obtained. Table 2-1 Common analyses used to assess the constituents found in wastewater Test Abbreviation/ definition Use or significance of test results Physical characteristics To assess the potential of reuse a wastewater and to determine the most suitable type of operations and processes for its treatment Total solids TS Total volatile solids TVS Total fixed solids TFS Total suspended solids TSS Volatile suspended solids VSS Fixed suspended solids FSS Total dissolved solids TDS(TS-TSS) Volatile dissolved solids VDS