treatment, the disposal of wastewater into freshwater and ... fish, human pathogens in recreation water, odor problems, ...... dardized measurements: a review.
Waste Water Treatment DL Jones, C Freeman, and AR Sa´nchez-Rodrı´guez, Bangor University, Bangor, UK Ó 2017 Elsevier Ltd. All rights reserved. This article is a revision of the previous edition article by D.L. Jones, C. Freeman, volume 2, pp. 772–781, Ó 2003, Elsevier Ltd.
Glossary Ammonification The conversion of organic N to NH4 þ by soil microorganisms. Biological oxygen demand The amount of dissolved oxygen consumed by organisms in wastewater during a 5-day incubation period. Denitrification The conversion of NO3 to N2O, NO and N2 by soil microorganisms. Macrophytes Large plants used in wetlands.
Nitrification The conversion of NH4 þ to NO3 by soil microorganisms. Polished water Water that has already been pretreated to remove most of the pollutant load. Total suspended solids The amount of particulate matter in wastewater. Wastewater Water that has previously been used for domestic, industrial, or agricultural purposes.
Abbreviations BOD Biological oxygen demand COD Chemical oxygen demand
TSS Total suspended solid
Introduction The safe disposal of both solid and liquid waste is of ever increasing concern due to the growing scientific and public awareness about the impact of untreated wastes on both human and environmental health. Although the most successful way to preventing environmental pollution is to prevent the formation of waste in the first instance (e.g., by enhancing water use efficiency, reducing packaging, recycling, etc.), it is inevitable that there will be a continued need for society to dispose of waste in an ecologically friendly manner. The aim of this article is to demonstrate the effective use of different plant-based strategies for the sustainable treatment of wastewater. However, some of the principles outlined below are also relevant to the treatment of other solid wastes. One example of this is the treatment of liquid effluent (leachate) produced as a consequence of the burial and subsequent decomposition of domestic waste in municipal solid waste (landfill) sites. As a society, we produce many types of liquid waste, which can be broadly classified into three categories: agricultural, industrial, and domestic waste (Table 1). Although these can range from highly toxic wastewaters (e.g., landfill leachate) through to relatively nontoxic wastewaters (e.g., storm drain water from road/urban runoff), many features of their treatment remain independent of waste type (e.g., reduction in biological oxygen demand (BOD), chemical oxygen demand (COD), suspended solids, and inorganic nutrients (NH4 þ , PO4 3 , Na); Table 2). Without remedial treatment, the disposal of wastewater into freshwater and marine systems can have catastrophic consequences resulting in both short-term impacts (eutrophication, death of
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fish, human pathogens in recreation water, odor problems, etc.) and long-term effects (loss of wildlife, build-up of toxic chemicals, etc.). Furthermore, improper disposal of wastewater onto land can result in the frequently irreversible loss of ecosystem productivity (e.g., due to salinization) and a pollution of groundwater resources. The treatment of wastewater by plant-based systems therefore requires careful management. The two most widespread types of wastewater management strategies that employ plants are (1) wetland treatment systems and (2) land-based treatment systems. They represent low-cost green technologies and have been used extensively in rural areas and developing regions in recent decades due to their ability to reduce pollution and their simple operation and management.
Table 1 Types of wastewaters that can be treated by either wetland or land-based plant-based treatment systems Domestic
Industrial
Agricultural
Untreated sewage
Acid minewater drainage Cooling water
Dairy parlor washings Pig and cattle slurries Sheep dips Vegetable washings
Partially treated sewage Road runoff
Encyclopedia of Applied Plant Sciences, 2nd edition, Volume 3
Metal processing Pulp and paper waste Chemical production Food processing Abattoir waste Landfill leachate Pharmaceutical
http://dx.doi.org/10.1016/B978-0-12-394807-6.00019-8
Table 2
Typical chemical composition (mg l1) of different types of wastewater commonly utilized in land-based and wetland treatment systems Urban stormwater runoff
Agricultural wastewater
Agricultural wastewater
– 220 220 500 1 25 15 – 8 – – – – – – – 1000 –
7.5 160 7 33 1 0.2 3 6 5 0.05 0.03 0.6 – – – – 100 000 16 000
– 500 500 850 – 70 20 – 20 – – – – – – – – –
– 500 500 850 – 70 20 – 20 – – – – – – – – –
Fish farm – 150 – 700
30 30 – – – – – – – – –
Raw sewage
Paper processing effluent
Cooling tower water
Oil refinery wastewater
Cheese production wastewater
Acid minewater drainage
River water
7.4 700 600 300 3.0 51 18 10 7 0.4 1.6 0.8 20 10 9.8 23 10 000 000 2 000 000
6.6 300 200–800 – – – –
7.3 70 150 150 – 50 – 400 6 – 2 1 162 – – – – –
8.4 350 10–1000 50–4000 1 87 – 700 49 – – – 310 – – – – –
7.1 500 1200 – – 38 36 500 – – – – – – – –
