Future Directions of Environmental Engineering.
This is an article about the future development of my major.
I still have many doubts about my major.
What kind of work will I do in the future?
Will I be able to use my professional knowledge in the future?
Maybe I need to find the answers to these questions slowly.
The world population has increased substantially over the past centry, as has the peoples'desire for a better quality of life. The resulting requirement for resoureces to improve the quality of human life has meant that organic and inorganic, living and non-living materials have been and will continue to be used to service peoples'needs and wants. This has resulted in a tremendous impact on the earth. During the past two millennia, air, water, and soil have been changed in a variety of ways, most of which originated with the attempts to meet the needs and wants of humans. In addition, for the past 12 000 years, the earth has been in a warming trend that has reduced the amount of water held in ice and snow masses and is now manifesting itself as "global warming".
The challenge of meeting human needs and wants is being met by an industrial and business aggressiveness that has never been seen before. The shock of the local, regional, and world impacts of meeting these needs has brought growing concern in many segments of the human population. The relationships between organisms and health, between chemicals and health, and between aesthetics and enjoyment of the environment require ways to make changes in what is done and how the residues are managed. Very early efforts at meeting the requirements were directed at the use of water.
A challenging aspect of environmental engineering is the rapid changes in the field due to the rate of knowledge increase in the fields of science and health. Accordingly, environmental engineers must understand the fundamental change to sustainable management and the legal, social, and political components related to it, but we also have a broad and expanding list of measurement and monitoring tools, new processes and technologies, and the need to examine complex inter-related systems. Overviews of the various areas and types of changes are summarized in the following sections.
Measurement and Monitoring Tools
The driving force for significant change in understanding impacts is the availability of measurement tools that accurately provide information for evaluation and model development. For environmental engineering, like most fields, the process of measurement requires two parts: (1) sample acquisition and (2) analytical techniques. Sample acquisition requires a very careful analysis of the sampling purpose, handling, and analysis methods.
In most cases, the collection of samples must conform to legal requirements for accuracy in collection and recording, as well as chain-of-custody requirements. In addition, the use of the Global Positioning System (GPS) means that the exact location of every sample can be identified at most locations on the earth.
However, the major imapct on the field has come from the chemistry and biological sciences. Table Ⅰ lists some of the recent and underdeveloped methods for determining the chemicals present in samples. The identification of microbiological constituents of samples will be more stringent as better methods for genetic identification are developed and accepted into practice. Indeed, it is possible that, within the next 10 to 15 years, in situ identifications may be possible. Table Ⅱ lists recent advances in microbial identification technologies.
Table Ⅰ New analytical methods-chemical
Inductively coupled plasma (ICP)
Gas chromatography (GC)
Mass spectrometry (MS)
High performance liquid chromatography (HPLC)
Inductively coupled plasma massspectrometry (ICP-MS)
Table Ⅱ New analytical methods-microbiological genetic finger print identification
Fluorescence in-situ hydration (FISH)
Polymerase chair reaction (PCR)
Denaturing gradient gel electrophoresis (DGCE)
Transmission electron microscopic (TEM)
Scanning electron microscopic (SEM) (cryogenic option, X-ray option)
Atomic force microscopy
Air Quality Issues
Air contaminants can be suspended particles, odour causing materials, hydrocarbons, toxic materials, volatile organic compounds (VOCs), aerosols, and microorganisms. All can adversely affect the health of humans, animals, plants, or microbial life. Typically, nationwide emissions are monitored as priority pollutants in the following categories: particulates, sulfur oxides, nitrogen oxides, hydrocarbons, carbon monoxide, and ozone as they contribute to the formation of smog. Controlling air pollution is not always easy because of the diverse sources and concentrations, with regulations usually developed to control emissions instead of ambient air quality.
In many cases, the use of scrulers, filters, covers, adsorbents, oxidants, electrostatic precipitators, and after-burnes has reduced the release of many contaminants. These are then combined with atmosgheric dispersion and natural atmosgheric reactions to minimize pollutant levels. However, the reduction of costs and the improvement of efficiency and reliability will continue to be major activities for development. New technologies such as biofilters provide a potential for capital and operating cost reduction, with increased reliability when applied. Support media and media replacement, as well as area required, appear as major engineering challenges to expanded use.
Adsorbed chemicals originating from the materials people use will also lead to an expansion of in situ treatment processes to reduce exposure to these materials. Examples include the reduction of chemicals in the indoor environment released from the materials of construction and finishing. Examples are organics from carpet and wood bonding agents, surface finishes, chaemicals used in washing and cleaning, and furnes from food processing.
In the future, air quality issues will focus on the areas: personal exposure and associated risk, contaminant impact on other living and non-living things, and the technological methods of reducing the adverse impacts of the above. If our ability to reduce the emission of contaminants from major point sources and automobiles continues, the major source of personal exposure to contaminants will be in the home and work place. New technologies to reduce the contaminants in the living environment are needed.
Wastewater System Issues
Although water and wastewater treatment have evolved into relatively complex technologies during the past 30 years, the ability to reduce the wide range of materials found in discharges in economical ways has not come into wide use. Society, through its political will has routinely decided that, in the face of limited knowledge, only those materials that have demonstrated adverse effects will be removed from water, wastewater, solid wastes, or gas streams.