Control of Groundwater Pollution from Bottom Ash Electro-Precipitation Process

Coal combustion technology is an alternative to cut down emission level caused by
combustion of energy. The use of coal will produce waste called bottom ash which may
contain heavy metal and can cause hazard if being exposed to the acid rain. Acid rain
directly can lead to groundwater pollution if the waste is being disposed directly into
water bodies without adequate treatment to remove harmful compounds. Contaminated
water by bottom ash is called leachate which can dissolve into ground water. Leaching
test is conducted to produce leachate from bottom ash. Electro-precipitation process is a
process to treat bottom ash by reducing heavy metals before being disposed. Through
this process, about 4.5% of heavy metals leached from bottom ash after react to acid rain
are determined. As the sample solution is more acidic (pH of 3.4), the amount of heavy
metals leached are up to 6.9%. This indicated that electro-precipitation is the processes
that can help in controlling bottom ash from pollute the groundwater.