WASTE WATER TREATMENT SYSTEM
DATE OF ISSUE:
11 OCT 2010
TABLE OF CONTENTS
2.3MATERIALS AND CONSTRUCTION6
3.FUNCTIONAL DESCRIPTION AND PRINCIPLES OF THE WASTE WATER TREATMENT PROCESS6 3.1WASTE WATER INPUT6
3.2PRIMARY TREATMENT - SEPTIC TANK7
3.3SECONDARY TREATMENT – BIOLOGICAL REACTORS7
3.4TERTIARY TREATMENT - SETTLEMENT TANK AND DISINFECTION:7 3.5OUTPUT PRODUCTS OF THE PROCESS7
4.2SUBSTANCES THAT MUST NOT BE INTRODUCED INTO THE SYSTEM8 4.3SUBSTANCES THAT MAY BE INTRODUCED IN LIMITED QUANTITIES9 4.4SUBSTANCES THAT MAY BE USED REGULARLY9
5.FIELD TESTING OF THE EFFLUENT9
DEFINITIONS OF TERMINOLOGY10
THE BIO-MITE® WASTE WATER TREATMENT SYSTEM
This document provides an overview of the sewage treatment process registered under the trade name Bio-Mite® (Biomite).
The Biomite water treatment system is designed to biologically treat raw sewage through a bacterial breakdown process requiring no chemicals. The waste stream flows through the plant under gravity, ensuring quiet operation and low energy demand.
The liquid effluent is safe to be returned to the environment and is suitable for non potable reuse such as irrigation. The output solids, of which a small amount is produced, are removed in the form of sludge for sanitation by sun drying in a suitable place, after which it can be used as fertilizer.
Apart from removal of the sludge (typically every 8-12 months if operated within specification), the system requires only minimal servicing and maintenance.
1.1.1The waste water/sewage is treated in a plant based on an enhanced natural bacteriological breakdown process followed by disinfection through oxidization. The treatment process consists of the following three phases, as illustrated in the diagram (Fig 1) below: •Primary treatment: Anaerobic digestion in the septic tank. •Secondary treatment: Aerobic digestion in biological reactors. •Tertiary treatment: Settling tank and disinfection unit. 1.1.2In the treatment process the waste water/sewage flows through a series of tanks where a biomass of bacteria progressively break down biodegradable waste and convert it into carbon dioxide and water. Any non- biodegradable matter collects at the bottom of the tanks and is periodically removed by pumping it out as sludge. 1.1.3The biomass is a colony of different bacteria that will naturally flourish in their particular habitat and that will survive as long as they have a suitable food source (the waste water/sewage) and a comfortable environment (sufficient oxygen and no harsh chemicals). The septic tank provides the food source and the design of the “Biological Reactors” the comfortable environment.
Fig 1: The three phases of the biological sewage treatment process
1.1.4The Biological Reactors consist of a matrix of plastic media in a honeycomb structure (to maximize the surface area) upon which the slimy bacteria cling. As the waste water circulates through the media “food” is delivered to the bacteria. A powerful air blower aerates the waste water introducing oxygen into the system and ensures that the waste stream is continuously circulated through the media. 1.1.5To produce effluent that is safe for re-introduction into nature, the waste stream is disinfected to kill any pathogenic organisms that may be present. This is done in the specially constructed disinfection tank. 1.1.6The bio-mite system has been designed to treat waste water from toilets (black water), showers or baths and kitchens (grey water). It is important that the...