Effluent & Sewage Solutions

OFT Projects has aligned its services to the provision of portable and efficient effluent treatment plants in addition to its OEM water treatment plant offerings. Our Modular Equipment provides rapid turnaround time and simple maintenance solutions once commissioned at the client's site. We represent market leaders in effluent technology who offer highly-efficient solutions that benefit both the environment and communities.

 

Black & Grey Water Solutions


 

Our plants are perfectly suited to provide rural communities, holiday resorts, mining facilities, factories, housing developments and smaller municipal wastewater treatment plants with reliable and low maintenance designs, durability, and energy efficient alternatives.

 

Submerged Fixed-Film Aerated Technology


 

Submerged fixed-film technology has proven itself over the last 40 years to be reliable and cost-effective, and we have over the last 20 years installed, commissioned and operated many successful plants in Africa. The process uses natural occurring bacteria and oxygen to reduce the BOD load and facilitate the nitrification and denitrification of ammonia.

 

The system comprises of 4 stages:


 

  1. Effluent flows via gravity to a collection sump or lifting station.

  2. Anaerobic and aerobic treatment employing bioreactors.

  3. Clarifier where settled sludge is recycled back to the anaerobic phase.

  4. Disinfection

 

The bioreactors used in the process contain high surface area PVC media to host natural bacteria. The key to our success is the patented Whale Tooth Technology TM aeration system, which utilises venturi’s, pressure cylinders and counters current flows to optimise aeration required for aerobic bacteria function. This, together with our Brush Filter and Matrix Cage Technologies protect our intellectual property and differentiates our technology from others.

Fixed-film systems produce very little sludge. Small quantities collected in the settling tank are returned to the anaerobic phase and broken down into methane gas, carbon dioxide and water. Depending on the volume and BOD influent values, the anaerobic zone (septic tank) will require de-sludging every 3-5 years.

Our effluent systems are robust with little maintenance requirements. The only moving parts are the pumps which operate automatically. Back-up aeration pumps and off-the-shelf components reduce downtime and trouble-free operation in all conditions across Africa. All our systems are designed to meet the Department of Water Affairs RSA general standards, applicable to discharge to a water resource.

 

Plant designs include three options

Concrete Systems


 

Generally for flows exceeding 200 kl/day. 

 

Containerised Systems:


 

50 kl/day 12m containers, or 25 kl per day 6m containers. This option is best suited for short to medium term projects such as construction camps. Modular designs are easily upgradeable to meet growing capacity loads, and location-specific demands can be accommodated in every design.

 

Freestanding Sewage Treatment Plants:


 

1 – 50 kl/day. Chemical grade, UV protected roto-moulded tanks are used. Where possible we prefer separating black and grey water effluents streams to optimise the recycling of grey water for alternative use. The low biological load in grey water allows for high recovery rates meeting standards for irrigation, toilet flush, process and wash water.

 

Membrane Reactor (MBR) Technology:


 

MBR technology is extremely efficient in treating high organic load effluent, including food process waste, industrial wastewater, effluent containing fats, oils & greases and sewage. Treated effluent complies with the Department of Water Affairs RSA general standards, applicable to discharge to a water resource, and may be used for irrigation, toilet flush and process wash water.

MBR technology combines membranes separation and conventional activated sludge (CAS) process. While the CAS process uses a secondary clarifier or settlement tank for solid/liquid separation, an MBR uses a membrane for this function, greatly improving solid-liquid separation and producing effluent of a very high quality. A Nominal pore size of membranes is typically 0.1 microns and effectively removes all suspended solids and virtually all bacteria and protozoa from the wastewater, resulting in a clarified and disinfected product effluent.

Since the sludge solids are completely retained in the bioreactor, this means the solids retention time in the bioreactor can be controlled separately from the hydraulic retention time. High sludge concentrations can thus be treated in a much smaller footprint and retention time than with other technologies.

Our bioremediation process is assisted by the addition of specific natural bacteria to significantly reduce COD, BOD and suspended solids, and effectively remediated fats, oils & grease as well as petroleum hydrocarbons. Odour control is through breaking down of hydrogen sulphide and complex mercaptans. Real bottom-line savings are achieved by increasing overall efficiency of the plants and reducing sludge removal frequency.

 

 




Please feel free to Contact us or browse our website to learn more about the extent of our combined services.