湿地 外文翻译.docx

1、湿地 外文翻译CROSS-REFERENCE TO RELATED APPLICATIONS0001 This application claims the benefit of U.S. Provisional Patent Applications Ser. No. 60/870,660, filed Dec. 19, 2006, entitled Wetland Water Treatment System which is hereby incorporated by reference in its entirety.FIELD OF THE INVENTION0002 The pr

2、esent invention relates, in general, to a water treatment system and a method of using the same. More particularly, the present invention relates to a system which removes pollutants from water and treats stormwater runoff or other grey water. This is system and method wherein the water is passed th

3、rough a wetland filtering and treatment system. This invention removes solids, metals (dissolved/particulate), nutrients (dissolved/particulate), oils, and bacterial contaminants from the water.BACKGROUND OF THE INVENTION0003 Water treatment systems have been in existence for many years. These syste

4、ms treat stormwater surface run-off or other polluted water. Stormwater surface runoff is of concern for two main reasons: one because of the effects of its volume and flow rate, and two, because of the pollution and contamination it can carry. The volume and flow rate of stormwater is important bec

5、ause high volumes and high flow rates can cause erosion and flooding. Pollution and contamination are important because stormwater is carried into our rivers and streams, from there into our lakes and wetlands, and furthermore because it can eventually reach our oceans. Pollution and contamination t

6、hat is carried by stormwater can have adverse affects on the health and ecological balance of the environment.0004 Beginning in 1972 with the passage of the Clean Water Act the federal government through the Environmental Protection Agency has mandated progressively tighter controls over the quantit

7、ies of pollutants and contaminants that are allowed to be released into our nations waters. These progressively tighter mandates also encompass control of peak flows and/or volumes and the rate at which they can be discharged into existing water ways or drainage infrastructures. These resulting mand

8、ates and controls have given birth to new programs and procedures collectively referred to as stormwater management. Devices and procedure that remove or reduce the pollutants and contaminates and/or control peak flows and volumes are often referred to as best management practices or BMPs. BMPs util

9、ize natural means, artificial or man-made means, and even combinations of either and/or both. Some examples of these BMPs include trash filters, sedimentation basins, retention and detention ponds, wetlands, infiltration trenches, grass swales, various types of media filters, and various types of na

10、tural filter systems including sand filters, and aggregate filters including natural and artificial wetlands. These BMPs typically use one or more mechanisms to remove the pollutants and contaminates. These mechanisms include sedimentation, filtration, absorption, adsorption, flocculation, stripping

11、, leaching, bioremediation, and chemical process including oxidation reduction, ion exchange, and precipitation.0005 Furthermore, stormwater treatment systems can also be classified in relationship to the treatment level in which they are being used. In this respect the term treatment is generally u

12、sed to describe the unit processes that are used to reduce the quantities of pollutants and containments in stormwater runoff. For example, basic or pre-treatment typically refers to the removal of gross solids, sediments and larger debris through the processes of settling and screening, while enhan

13、ced or advanced treatment typically refers to processes for reducing targeted pollutants; filtration being the main form of enhanced treatment for stormwater. Filtration utilizes a combination of physical, chemical, and biological processes. Types of filtration greatly vary dependent on the media us

14、e. Medias can be both inert and/or sorbent and are also strongly linked to natural biological processes that thrive in and/or around the media environment. Advanced filtration techniques especially include chemical and biological processes and generally include, but are not limited to processes that

15、 bring stormwater in contact with plants including both macrophytes and microphytes, plants that are both visible and invisible to the naked eye. One type of stormwater treatment system that is especially effective at advanced treatment is known as a wetlands system or often simply referred to as a

16、wetlands.0006 When creating a constructed wetlands, the objective is to minimize the size of the media to maximize the surface area of the media and to also maximize contact time with possible biofilm which can grow on the media, but also to provide media sufficiently large so that the interspacing

17、will not be occluded with the sedimentation that is being carried in the treated water. Accordingly, as a matter of practicality it makes sense to remove as much sediment as possible before allowing the water to enter the wetlands system. In this respect the design of an effective treatment system w

18、ould contain sufficient screening to remove trash and debris, sufficient sedimentation to remove sediment to a level sufficient to maximize the use of the wetlands. And to preserve efficient operation of the system, the system should be operated at an appropriate flow rate that maintains and preserv

19、es the life and operation of the system as a whole. The average or mean time that water remains in contact with the wetlands system is termed the hydraulic resident time or HRT of the wetlands.0007 Given uniform flow through the sediment chamber, the sedimentation HRT is proportional to the volume o

20、f the chamber and inversely proportional to the flow rate. The time required for a particle to settle a specific distance is often referred as the settling time for that particle size and density. Because deeper settling chambers require a greater distance for particles to settle, deeper settling ch

21、ambers have longer respective settling times. And, because the volume of a sediment chamber is also proportional to the depth of the chamber, increasing the depth increases both the volume (and thereby the HRT) and the settling time. Therefore, increasing the depth of the chamber increases the HRT,

22、but may not increase settling efficiencies since the distance to settle increases proportionally with increase in HRT. Accordingly, the overriding principle of achieving effective sedimentation is to provide the maximum surface and floor areas in the chamber as possible. Other considerations are to

23、increase the path length through the sediment chamber to increase the uniformity of the flow and to prevent high flow rate conditions from re-suspending existing sediment (often referred to as scouring).0008 In a similar manner, the basic principles separation that apply to the settling of particles

24、 more dense than water apply to particles that are less dense than water except that the particles float to the surface rather than settle to the bottom of the chamber. Because oils and hydrocarbons are typically less dense than water, because these products can often be separated mechanically by fl

25、otation, and because the products can create adverse biological demands on a wetlands system placed downstream of the sedimentation and flotation chamber, it makes sense to allow the floatable products to remain in the chamber and to remove the out-flow water from below the surface.0009 Because the

26、objective of a sedimentation and flotation chamber is to remove sediment and floatable products from the incoming water, the accumulated sediment and floatable products will require periodic removal. Systems that are configured to allow easy removal of these products will undoubtedly provide reduced

27、 maintenance costs.0010 Flow-rate control is another consideration. Because the performance of some BMPs like sedimentation and flotation chambers and wetlands systems is dependent on hydraulic resident times (HRTs), optimum performance can be obtained by having sufficient control to not allow flow

28、rates to vary excessively beyond certain limits. Devices that can be used to control the flow rate include bypass controls and inlet and outlet control systems such as adjustable valves or orfice plates.0011 Because some treatment locations may have high levels of specific pollutants and contaminate

29、s, specific configurations using additional BMPs may provide benefits and advantages above typical or standard configurations. Such BMPs may include additional filter systems, additional media chambers, aeration, bioremediation systems, irrigation systems, and mixing manifolds. Any system that can b

30、e configured to accommodate additional devices and methods of pollution and contaminate removal is by definition a more versatile BMP.0012 There is, thus, a need for a wetlands stormwater treatment system which can treat high levels of specific pollutants and contaminants.SUMMARY OF THE INVENTION001

31、3 This invention involves a method for manufacturing and using a wetlands water treatment system (system) which is reliable, dependable, effective, low maintenance and structurally sound. This is a self-contained wetlands treatment system. The system and housing is easy to maintain and construct. It

32、 increases the ability to remove nitrogen with the addition of an anaerobic environment in the lower chamber which promotes denitrification. The system and system housing can be fabricated, built, and assembled in a broad range of sizes and materials to accommodate and treat a broad range of influen

33、t flow rates. The functional components of the system can be selected, sized, tailored, and assembled to provide a range of performance and options from basic configurations to customized configurations which provide levels of performance suited to specific or individual situations which may require various unique solutions t