Encyclopedia of Environmental Science and Engineering, Volume I and II

INSTRUMENTATION: WATER AND WASTEWATER ANALYSIS 543

Twenty-five years ago the dearth of instrumentation was

used in Standard Methods.^4 However, in the present edition

the following instrumentation is employed in the method-

ologies: molecular spectroscopy (visible, uv, ir), atomic

spectroscopy (absorption, flame, ICP), chromatography

(gas, ion, liquid), mass spectrometry (GC/MS, gas chroma-

tography/mass spectrometry), electro-analytical techniques

(polarography, potentiometric and amperometric titrations,

selective ion electrodes), radio-activity counters (gas filled

and semiconductor detectors and scintillation counters), and

automated continuous-flow methods.

Also included in Standard Methods are aspects such as

safety, sampling, mathematical treatment of results, reagents,

apparatus etc. It is fortunate, indeed, that such a compre-

hensive work is available and that it is regularly revised.

Enlightened editorial leadership and the many members of

the Standard Methods committees in the last twenty years

can be credited for the steady increase in the inclusion of

instrumentation in Standard Methods. In the increasing com-

plexity of environmental and ecological problems and guid-

ance of Standard Methods is a valuable and practical support

in obtaining necessary analytical data.

The American Society for the Testing of Materials,

ASTM, is an important compendium for the analysis of raw

and finished material products. A large section is devoted

to the analysis of water and wastewater in the context of

processing and usage.^5

The EPA has published instrumental methods for the

analysis of priority pollutants and other substances controlled

by Federal legislation.^6

Types and Purposes of Instrumentation and Computer

Systems

The development of a large variety of analytical instru-

mentation has been a boon to water and wastewater char-

acterization, research, management, and process control.

In addition to the requirements of the process industries,

the needs of the water and wastewater area have spawned

the development of some specialized laboratory, monitor-

ing and process control instrumentation. Some examples

are the total carbon and organic carbon analyzers, biologi-

cal oxygen analyzers and the residual chlorine analyzer.

Monitoring and data acquisition systems, in conjunction

with this instrumentation, are increasingly used in waste-

water management and plant process control. Certainly a

number of physical parameters such as temperature, flow

rate, pressure and liquid level have been measured instru-

mentally in the process industries, including wastewater

treatment plants, predating the development of this wide

variety of analytical instrumentation.^7

Instruments utilized in the measurement of parameters

important to wastewater analysis, treatment and manage-

ment can be divided into two categories based on application.

Monitoring of water bodies and waste treatment processes

require monitoring instruments which are characterized by

ruggedness and capability of unattended operation and data

storage and/or transmission. A second category, laboratory

instruments, in many instances, may be more sophisticated,

sensitive to the surrounding environment and also have data

storage and transmission capabilities. Each type has its spe-

cific utility in the scheme of analysis and data acquisition

for wastewater characterization and processing. In many

instances monitoring instruments are laboratory devices

which were ruggedized and prepaared for field use. Thus

the variables measured and the principles of operation are

the same in many cases. Some examples of variables mea-

sured by laboratory and monitoring instrumentation are pH,

conductivity, DO (dissolved oxygen), specific cations and

T A B L E 2

Some water quality parameters a

Physical Chemical Biological

Color Acids or alkali Algae

Conductivity Ammonia Bacteria

Odor Biochemical oxygen demand Pathogens

Radioactivity (BOD) Protozoa

Solar radiation intensity Calcium Viruses

Suspended solids or Chloride

sludges Chlorophyll

Temperature Chemical oxygen demand

Turbidity (COD)

Dissolved oxygen

Hardness

Heavy metals:

Chromium

Copper

Iron

Lead

Manganese

Mercury

Magnesium

Nitrate, nitrite

Organic compounds:

Detergents

Herbicides

Pesticides

Phenol

Oils and greases

Oxidation–reduction potential

pH

Phosphates

Potassium

Sodium

Sulfate

Total organic carbon (TOC)

a Reprinted from Ref. (4), p. 1438 by courtesy of Marcel Dekker, Inc.

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