As the era evolve and ameliorate, technology has improved much to make a better human life with convenient and comfortability. Yet, as the world is improving, the pollution caused to the environment has deteriorate day by day, especially water pollution. One of the major role of pollution in water pollution is industrial wastewater (Hanchang SHI, no date). Most of the sources of water before treatment is from surface water, which include rivers, dams, lake and so on. Water pollution can be caused by several reasons for example dumping, industrial waste, acid rain, global warming and so on. Based on WWF Malaysia CEO Datuk Dr Dionysius Sharman said water pollution has become a critical issue in Malaysia and brought a huge negative effect on maintainability of Malaysia’s water resources. Especially the water quality of coastal water in the area of Klang and Kuala Langat was below the Environmental Quality Act (EQA) standard, it was because of the raise of waste throwing into the river specially from dwelling and manufacturing areas, also the discharge from human activities suchlike agriculture and land evolvement (The Rakyat Post, 2015). Therefore, water is very important as it is one of the human basic needs.
Industrial waste is a waste or material produced during some manufacturing activities such as mining, car service centre, factories and industries operation. Industrial waste contains toxic heavy metal pollutants like Mercury (Hg), Cadmium (Cd), Arsenic (As), Chromium (Cr), Cobalt (Co), Lead (Pb), Zinc (Zn), Copper (Cu), Nickel (Ni) etc (HuiHu, QianJin, Kavan, 2014). As water is used as a raw material in production and cooling process, different waste will be brought into the water during the manufacturing process (Hanchang SHI, no date). Therefore, if the effluent of industrial waste to surface water does not have a proper control and adjustment according to the Environmental Quality Regulations, it is bitterly pernicious to human health and environment. It is due to the heavy metal in the wastewater is non-biodegradable in nature and they are soluble in aquatic environment thus can be easily absorbed by aquatic living organisms. Thus entering the food chain, they can be bioaccumulated and biomagnified in higher trophic level (Tripathi, Ranjan, 2015). Some heavy metal with certain limit or dosage can be a medicine to human but once exceeded the limit toxicity may develop and accumulate in our body which will inimical to our health (Renge, Khedkar, Pande, 2012).
The most conventional way to reduce or limit the dosage of heavy metal effectively in the industrial effluent is adsorption by using activated carbon (S. Chand, et.al,1994), while there are a broad choice of adsorbents such as clays, bentonite, fly ash, alumina, magnesium oxide, ferric oxide, silica, zeolite and activated anthracite volcanic ash soil (Rath, Puranik, 2001). Yet all the adsorbents mentioned above are expensive and contained of chemical which are not economical and eco-friendly. Hence, scholars have tried on low cost material suchlike coconut shell, chitosan, egg shell, saw dust and mango leaves as an alternative of activated carbon which work effectively and can obtained easily (Renge, Khedkar, Pande, 2012).
Nowadays, peoples are looking for a more safety and more economical ways to eliminate heavy metal from wastewater through adsorption process. As adsorption process is defined as the adhesion of chemical species onto the surface of particles (Helmenstine, 2018), in the other words the heavy metals will be adhere with adsorbent and heavy metals are eliminated after a simple filter process by filter paper. Thereupon, this research paper is aimed to conduct adsorption by using low cost, natural and eco-friendly material (rice husk) as adsorbent in the treatment of effluent containing heavy metal instead of activated carbon.
Statement of Problem
As the advance technology has developing rapidly, it has gave a great effect increasing in the accumulation of heavy metal every day in daily life through wastewater and the common ways used to remove heavy metal from polluted wastewater are chemical precipitation, ultra-filtration, ion-exchange, reverse osmosis, carbon adsorption, phytoremediation etc (Joshi, 2017). Yet these process bring disadvantages even though it remove heavy metal from contaminated wastewater.
Firstly, chemical precipitation process might seem simple, cheap and effective but it will produce a huge amount of sludge and will caused disposal problem (Farooq et.al, 2010) because if it is sent to landfill or act as fertilizer it will caused land pollution since it contain high content of heavy metal. Besides, ultrafiltration with membrane process is very high efficiency but high initial and running cost needed also with low flow rate which mean ultrafiltration take longer time for removal than other process. Furthermore, ion-exchange can remove metal selectively but it need high cost and partial removal of certain ion (Joshi, 2017). Therefore we can conclude that most of the chemical process will produce gigantic amount of sludge which will cause disposal problem, non-eco-friendly also needed high initial and running cost.
Without a proper way to remove heavy metal in wastewater, it will not only caused water pollution but also many diseases and illness will be caused if peoples are contacted with contaminated wastewater for a certain duration such as dead, cancer, blood contamination, bronchitis, tuberculosis, catarrhs, nasal discharge, loss of Intelligent Quotient (IQ), hair, teeth, nails and kidney function (The Guardian, 2018) (Mongabay, 2018).
The purpose of this research is to remove heavy metal contained in wastewater before industries effluent discharged to surface water. In order to achieve this goal, following objectives must be accomplish:
To investigate the quality of effluent from Bangi Perodua Car Service Centre.
To determine the suitability of rice husk as the bio-sorbent in removal of Cu(II) and Zn(II) from aqueous solution using bio-adsorption process.
To investigate the effect of pH, initial concentration, bio-sorbent dose and particle size on the bio-adsorption capacity of rice husk on Cu(II) and Zn(II).
Scope of Study
In this research, rice husk is acted as the adsorbent. It will be collected from Sekinchan Paddy Processing Factory and Gallery. Rice husk will be collected in a plastic container and will be brought back to IUKL environmental lab within 2 hours for further lab work. Rice husk is washed by distilled water and dried in oven at 100°C for 24 hours. Next the dried rice husk will be grounded into powder by laboratory mill and rice husk powder will be stored in an airtight plastic container for further usage to avoid it contact with atmosphere moisture. While 5L of industrial wastewater sample will be collected from Bangi Perodua Service Centre and will be transported back to IUKL environmental lab within an hour to avoid any changes due to environment.
Batch experiment is carried out to check all the parameters going to be tested from the wastewater sample collected from Bangi Perodua Service Centre which are pH, initial concentration, bio-sorbent dose and particle size of rice husk. All parameters are checked in room temperature ± 28 °C with a pH ranging from 4 to 9.
Significant of Study
Removal of heavy metal in industrial wastewater is a must to be done before the effluent discharged to surface water with a natural, economical, eco-friendly and effective adsorbent. It is because heavy metal can enter our body through air, water and food. A small quantity of metals are required for living things health and growth but once it exceed the needed concentration, it may cause a huge impact on our health and the environment (Gautam et.al, 2014). Therefore, removal of heavy metal by using rice husk bring lots of benefit to us.
Firstly, people will become healthier since the metal contained in wastewater are reduce without adding any chemical in. As we know excessive of Copper will cause a metal fume disease which look a flu-like reaction and disturbances in blood. While overexpose of Zinc might cause flu-like symptoms of metal fume fever, stomach and intestinal disturbance and liver dysfunctional (NORD, no date).
Next, we will have a better environment by reducing heavy metal in contaminated water, reduce agriculture waste produced and reduce pollutions in all aspect. Using chemical process to remove heavy metal will produce a large amount of sludge that may need to send for disposal or landfill. While agricultural waste (rice husk)is used as replacement of activated carbon, since an enormous amount of rice husk is produced annually, most of the rice husks are discarded because rice husk doesn’t has any commercial potential which result in environmental pollution. The utilization of rice husk as adsorbent can extremely reduce the amount of waste produced.
Moreover, as all the chemical removal processes required high initial, running and maintenance cost because they required specialise skilled manpower, machines, a huge area of land and so on. Therefore, the adoption of rice husk can reduce the cost of process with high efficiency of metal removal from aqueous solution and easily available in market. Furthermore, by doing this research we can enhance the process did previously by other scholars. Therefore we can use the latest technology to help the world by reducing pollution in every aspect.