Wastewater treatment system and method

Abstract

A system, method and apparatus for treating wastewater containing biodegradable material wherein a submerged stand alone perforated cylinder reactor pod containing aerobic bacterial growth media and a draft tube with air pressure induced pumping action creates a spray or splash pattern so as to recirculated aerated liquor through the media and also to the area surrounding the cylinder pod. Free interchange of mixed and unmixed liquor is provided via the perforations in the cylindrical pod wall. Provision is also made for back flushing the media and returning mixed liquor to an area remote from the reactor pod.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to on-site wastewater (sewage) treatment systems and processes, and more particularly to a stand-alone aerobic treatment unit or pod system for promoting oxygen transfer and aerobic bacterial activity in conjunction with conventional septic tank systems for family residences and commercial establishments. [0003] 2. Description of the Prior Art [0004] At present, many single and multiple family dwelling units as well as small commercial installations rely upon the well known process of wastewater (sewage) disposal involving a septic tank and drain field installation. In these installations the biodegradable wastewater contains a wide variety of solid and liquid materials which are introduced directly from the source into a septic tank for primary treatment. The septic tank itself functions as a settling chamber in which the solids are allowed to settle out in a quiescent zone with both l...

AI Technical Summary

Benefits of technology

[0009] In order to increase the effectiveness of the treatment of the liquid in the tank, a return line may be installed for the purpose of collecting a predetermined volume of oxygen rich aerated liquor from the spray pattern and returning it to the quiescent or settling zone of the tank in the general area of the inlet. In this manner, the entire volume of the tank may be converted from an anaerobic to an aerobic digestion processes. A buoyant microbial growth media is preferred for containment in the cylindrical reactor pod. Although this media does not tend to incur flocculent build up during normal operation, a back flushing feature for scrubbing off organic build up and preventing the process from becoming anaerobic is provided. A back flushing air pressure manifold is located in the bottom end of the cylindrical pod which may release air jets upwardly from a manifold in order to scrub off organic build up and to create a turbulent zone to increase treatment and oxygen transfer if desired.

[0010] The features of the present invention include the ability to add or withdraw self contained stand alone reactor pods to accommodate the actual organic waste load at a given site or under given conditions of loading. The pod as described is preferably a cylindrical open ended cylinder supported on the bottom of the septic tank. When used in the normal septic tank environment, the tank will be fitted with access openings and the diameter of the cylindrical pods may be chosen so as to allow for easy insertion and withdrawal of pod units as the situation dictates. This is also made possible by the fact that the reactor pods can be made as a stand alone self contained unit not connected in any way to the structure of the septic tank.

Problems solved by technology

The anaerobic treatment system is extremely slow compared to aerobic processes whereby oxygen is introduced and absorbed into the wastewater so that aerobic micro organisms are relied upon to provide aerobic metabolism of sewage organics.

Filter systems and / or chemical treatment processes have been used for both large and smaller installations, however, such systems tend to be complex, expensive to install, unreliable and difficult to maintain.

Thus, only the liquor-effluent within the reactor chamber is being aerated and mixed leaving the balance of the volume within the settlement tank untreated.

The major part of the septic tank thus remains anaerobic with the usual inefficient and slow odor producing decomposition attendant standard septic tank systems.

The volume of liquor treated is thus limited and frequent clogging of the media and / or filter system may occur with ultimate failure of the tank system during overload periods or after long use.

Systems of this type may also employ pumping devices which must be regulated in such a manner as to accommodate variations in flow volume and timed dosing, resulting in frequent failures and a fluctuating liquid depth within the septic tank.

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