Differential equation
The chemical waste pollution of Sungai Kim Kim in 2019 is a water pollution incident that
occurred on March 7, 2019, caused by the dumping of chemical waste in Sungai Kim Kim in
Pasir Gudang, Johor, Malaysia. Some students and canteen workers from two schools near the
river began to fall ill and complained of difficulty breathing, until they were sent to Sultan Ismail
Hospital.
Through investigation, a tanker is believed to have dumped chemical waste into the Kim Kim
River early in the morning before the victim fell ill. Johor's Department of Environment (JAS) has
arrested a chemical factory owner in Kulai on March 10 followed by another arrest involving a
waste factory owner and one of the workers in Taman Pasir Puteh the following day after a
series of investigations. The investigative team has also identified the illegally dumped
chemicals as marine oil that emits flammable methane gas and benzene fumes. Several other
types of toxic gases have been identified as released following the interaction of chemicals that
react with water and air including acrolein, acrylonitrile, ethylbenzene, hydrogen chloride, D-
limonene, toluene and xylene which can cause headaches, nausea, fainting and difficulty
breathing if inhaled..
Assume that the pollution modeling of Sungai Kim Kim is done using several tanks that
represent several segments of the polluted water flow of Sungai Kim Kim. For a tank, the
maximum capacity is 1000 liters of water and it receives an inflow of contaminated water from
the chemicals above with the initial amount of water in the tank being 800 liters with 2 grams of
chemicals dissolved in it. Contaminated water flows into the tank at a rate of 3 liters/hour and
contains 5 g/liter of contaminated chemicals. Contaminated water flows out of the tank at a rate
of 3 liters/hour as well. When the amount of contaminated material in the tank reaches 500 g of
contaminated water flow
inflow is stopped and clean water will enter the tank at a rate of 2 liters/hour while the outflow
increases to 4 liters/hour. Determine the amount of pollution in the tank at any time t.
