『Abstract
Constructed wetlands (CWs) have been used in ecological engineering
for more than two decades, since 1990. In order to understand
the present application and trend of CWs in China, this paper
summarized the status quo, prospect and influencing factors in
CWs construction, technology application and operation management
in China, according to the data obtained by literature survey.
Results of the systematic survey showed that CWs technology achieved
gradual perfection under pushes of national policies, market demand
and technical feasibility, with the capacity of wastewater treatment
increasing year by year. However, there were still some problems
concerning engineering operation and management. Moreover, the
results demonstrated that limited by the economic level, the degree
of industrialization and urbanization, climatic conditions as
well as land availability, CWs were distributing predominately
in the region of 20゜13'N-35゜20'N in China, where covered the central
areas with a subtropical monsoon climate and southern or central
areas at province level. In these areas, there were more than
40 plant species, which accounted for 57.14% of the total number
of common wetland plants. Most of the CWs composted series or
parallel combination forms of the vertical flow and free water
surface flow CWs units, and they were suitable to treat more than
20 different types of wastewater. For these CWs, the effluent
chemical oxygen demand (COD), biological oxygen demand (BOD),
total nitrogen (TN) and total phosphorous (TP) reached in the
ranges of 20-60 mg/L, 4-20 mg/L, 1-20 mg/L and 0.2-1 mg/L, respectively.
The effluents from CWs were reused in more than eight ways, such
as for agricultural irrigation, supplying surface water, green
belt sprinkling, etc.
Keywords: Constructed wetland; China; Project; Wastewater treatment』
1. Introduction
2. Investigation method
3. The situation and trends of CW's construction and management
in China
3.1. The quantity of constructed wetlands in China
3.2. The capacity of CWs for wastewater treatment
3.3. The issues of CWs operation and management
4. Engineering applications of different types of CWs system
4.1. Regional distribution of different process types of
CWs
4.2. Types of wastewater treated by CWs
4.2.1. Three types of CW applications
4.2.2. Engineering application of combined CWs
5. Distribution status of commonly used CWs plants
6. Situation of CWs effluents in China
7. Conclusions
Acknowledgements
References