Further Details for Waste Incinerator and Waste Water Treatment System
lens1.1 Process Flow Chart
1.2 System Description
Waste matter is to be fed manually into the incinerator. The incinerator comprises primary and secondary combustion chambers with diesel being used to fuel the combustion process. After incineration in the first chamber, a second round of incineration takes place in the second chamber at temperatures in excess of 1,1000C to burn off leftover hazardous substances. Air blowers are used to supply the oxygen required for combustion, which can be controlled by adjusting the air flow rate inside the furnace. The flue gas from the second chamber is then passed into a cooling tower where the temperature of the gas is brought down to 180-2000C by scrubbing with alkaline substances. At the same time, acidic gas content is reduced.
The flue gas then passes through the cyclone dust removal system where fly ash is forced out of the system. The gas then enters the activated carbon filter where metal content in the flue gas is reduced before being discharged safely through a chimney into the atmosphere. Air quality will be monitored frequently to detect any possible deviation from National standard guidelines. If any deviation is detected, the process will be paused until the problem has been identified and solved.
2.0 Waste Water Treatment
lens2.1 Process Flow Chart
2.2 System Description
Waste water is first collected in the collecting basin and then passed into the fine screen where large solids and trash are screened out before the water enters the equalization tank. In the equalization tank, air diffusers are used for even mixing of the waste water. The water is then transferred via submersible pump into the fast-mixing tank where pH adjustment and chemical coagulation are conducted. The resulting sludge is settled in the chemical sludge sedimentation tank whereas the water is passed as overflow into the activated sludge aeration tank. In this tank, aerobic bacteria is used to digest organic matter to reduce the BOD. In order to facilitate this process, oxygen is supplied through air diffusers. The overflow is then passed into the second sedimentation tank where the sludge is settled and transferred into the sludge tank.
The water is then passed through activated carbon filters to remove any odour and colour and then temporarily stored in the effluent tank where water samples are to be taken and analyzed before being discharged into the man-made fishpond next to the treatment facility.
In the event that the water content is unsuitable to be discharged into the pond, the water will be re-directed into an emergency storage tank and then recirculated back to the equalization pond for re-treatment.
The sludge will enter a dehydrator where it will be filter pressed into dried sludge cake. The water from the dehydrator is recycled back into the equalization basin whereas the sludge will be sent to the incinerator to be burnt off.