Amir Hashim Mohd Kassim

A monitoring of environmental effects from household greywater reuse for garden irrigation.

The option of reusing greywater is proving to be increasingly attractive to address the water shortage issue in many arid and semiarid countries. Greywater represents a constant resource, since an approximately constant amount of greywater is generated from kitchen, laundries, bathroom in every household daily, independent of the weather. However, the use of greywater for irrigation in particular for household gardening may pose major hazards that have not been studied thoroughly. In this study, a 1-year monitoring was conducted in four selected households in Perth, Western Australia. The aim of the monitoring works is to investigate the variability in the greywater flow and quality, and to understand its impact in the surrounding environments. Case studies were selected based on different family structure including number, ages of the occupants, and greywater system they used. Samples of greywater effluent (showers, laundries, bathtub, and sinks), leachate, soil, and plants at each case study were collected between October 2008 and December 2009 which covered the high (spring/summer) and low (autumn/winter) production of greywater. Physical and chemical tests were based on the literature and expected components of laundry and bathroom greywater particularly on greywater components likely to have detrimental impacts on soils, plants, and other water bodies. Monitoring results showed the greywater quality values for BOD, TSS, and pH which sometimes fell outside the range as stipulated in the guidelines. The soil analyses results showed that salinity, SAR, and the organic content of the soil increased as a function of time and affected the plant growth. Nutrient leaching or losses from soil irrigated with greywater shows the movement of nutrients and the sole impact from greywater in uncontrolled plots in case studies is difficult to predicted due to the influence of land dynamics and activities. Investigative and research monitoring was used to understand greywater irrigation in households. Greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater. Investigative and research monitoring was indicated that greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater.

Harvesting of microalgae biomass from the phycoremediation process of greywater

The wide application of microalgae in the field of wastewater treatment and bioenergy source has improved research studies in the past years. Microalgae represent a good source of biomass and bio-products which are used in different medical and industrial activities, among them the production of high-valued products and biofuels. The present review focused on greywater treatment through the application of phycoremediation technique with microalgae and presented recent advances in technologies used for harvesting the microalgae biomass. The advantages and disadvantages of each method are discussed. The microbiological aspects of production, harvesting and utilization of microalgae biomass are viewed.

Production and harvesting of microalgae biomass from wastewater: a critical review

The wide range of microalgae applications has increased in the last decade, due to their importance as the source of biofuel and biomass. The potential of wastewater as a culture media lies in the presence of high contents of nutrients and elements required to improve the growth of microalgae and, thus, the high quantity of biomass. However, these properties might be the limitations in the harvesting of microalgae biomass from wastewater. This review discussed the potential of wastewater as the production media for biomass and focused on the harvesting methods, because it represented a major challenge in the quality and quantity of microalgal cells. It can be concluded that among several technologies used for harvesting microalgae biomass from wastewater, the natural flocculant method was the most efficient due to the absence of toxic by-products and secondary effects on the quality of biomass yield, as well as the high biomass quantity.

Treatment of Wastewater From Car Washes Using Natural Coagulation and Filtration System

Wastewater generated from carwash is one of the main wastewater resources, which contribute effectively in the increasing of environmental contamination due to the chemical characteristics of the car wastes. The present work aimed to develop an integrated treatment system for carwash wastewater based on coagulation and flocculation using Moringa oleifera and Ferrous Sulphate (FeSO4.7H2O) as well as natural filtration system. The carwash wastewater samples were collected from carwash station located at Parit Raja, Johor, Malaysia. The treatment system of car wash wastewater was designed in the lab scale in four stages included, aeration, coagulation and flocculation, sedimentation and filtration. The coagulation and flocculation unit was carried out using different dosage (35, 70, 105 and 140 mg L-1) of M. oleifera and FeSO4.7H2O, respectively. The efficiency of the integrated treatment system to treat carwash wastewater and to meet Environmental Quality Act (EQA 1974) was evaluated based on the analysis of pH, dissolved oxygen (DO), chemical oxygen demand (COD) and turbidity (NTU). The integrated treatment system was efficient for treatment of raw carwash wastewater. The treated carwash wastewaters meet EQA 1974 regulation 2009 (Standards A) in the term of pH and DO while, turbidity and COD reduced in the wastewater to meet Standards B. The integrated treatment system designed here with natural coagulant (M. oleifera) and filtration unit were effective for primary treatment of carwash wastewater before the final disposal or to be reused again for carwash process.

Application of Phycoremediation using Microalgae Scenedesmus sp. as Wastewater Treatment in Removal of Heavy Metals from Food Stall Wastewater

This paper represents the results of using phycoremediation technology in treating the wastewater produced from food stall activity by using microalgae of Scenedesmus sp. in removal of heavy metals. Phycoremediation has advantages over physic-chemical approaches as it is can completely degrade organic pollutants without destroy the surrounding flora and fauna. Aim of this study is to determine the effectiveness of microalgae Scenedesmussp to assimilate the pollutant load based on the optimum time and concentration. Characteristics of food stall wastewater need to be identified and analyse before phycoremediation process taken place. The wastewater sampling was collected at food stall during peak time i.e. at 8 a.m. and 4 p.m. Microalgae Scenedesmus sp. to be injected to the batch reactor based on five (5) different concentration cells. The results shows that the optimum removal of heavy metals are dominant by concentration no. 1 (C1) compare to other concentration in the treatment i.e. removal of Ferum by 88.22% and 69.63%, Copper by 60% and 53.85% at both sampling time while removal of zinc is dominant by concentration no.4 (C4) by 75.61% and 76.63% respectively.

Consequences of the Improper Disposal of Greywater

Discharge of greywater into the environment and natural water bodies is the main challenge in the management of greywater. The increase of greywater disposed into the environment has drawn serious attention from the society and the government who endeavour to find a safe alternative way for the disposal of these wastes. The implication for the improper disposal of greywater is associated with infectious agents. This is because the organisms are able to multiply in the environment and might reach the infective dose which causes several diseases in human and animals. In this chapter, the health risks and effects posed by pathogens and heavy metals in disposed greywater to the environment and humans are reviewed. The chapter discusses the level of risk for each component in greywater. It has appeared that eutrophication and water bloom are associated with the discharge of greywater into the natural water due to the high level of nutrients.

Removal of Nutrients from Meat Processing Wastewater Through the Phycoremediation Process

Wastewater from slaughterhouses and meat processing factories are normally assessed in terms of mass parameters due to the specific amounts of wastewater and pollutant load parallel to the animals slaughtered or processed that differ from the meat processing industry. Normally, this type of wastewater contains significant amounts of total phosphorus (TP), total nitrogen (TN), total organic carbon (TOC), chemical oxygen demand (COD), total suspended solids (TSS) and biochemical oxygen demand (BOD). The present chapter aims to highlight the characteristics of meat processing wastewater and the effect of the direct disposal of these wastes on the environment. Moreover, the potential of the phycoremediation process using microalgae species to remove nutrients in terms of total nitrogen (TN) and total phosphorus (TP) from the meat processing wastewater was reviewed. The role of a biokinetic study in determining the specific removal rate of nutrient by microalgae was also discussed.

Determination of Pathogens in Greywater

There are many methods used for isolation and the enumeration of pathogenic organisms. The direct methods depend on the culture medium and microscopic examination. However, these techniques are not effective for all pathogenic organisms in the environment since many organisms require a specific condition to grow on the culture medium. Therefore, the using of enrichment methods might exhibit more efficiency in the determination of pathogens from the wastewater samples. The main challenge in the microbiological assessment of greywater lies in finding the most effective method to detect the presence or absence of pathogens which are available in low concentrations. In this chapter, traditional methods including direct culture and enrichment methods are reviewed.

Disinfection Technologies for Household Greywater

The treatment technologies for greywater are followed by the disinfection processes in order to achieve safe disposal into the environment. The disinfection technologies aim at reducing or minimising the concentrations of the pathogenic microorganism of greywater which have a high potential risk for humans and plants, and, thus, provide safe and aesthetically acceptable greywater that is appropriate for the purpose of irrigation. The disinfection processes include chemical (chlorination and ozonation), physical or mechanical (filtration process) and radiation disinfection (UV irradiation, solar disinfection (SODIS)). The degree of the disinfection process proposed must take into account the type of reuse and the risk of exposure to the population. In this chapter, the disinfection techniques of greywater are reviewed and discussed based on their efficiency to eliminate the pathogenic bacteria and other toxic by-products. The objective of this chapter was to discuss the advantages and disadvantages of disinfection processes. Among the several disinfectant technologies for greywater, SODIS appears to be the most potent technology which is widely applicable in most of the developing countries experiencing arid and semi-arid atmospheric conditions due to the high density of sunlight which is more effective for inactivating pathogenic microorganisms.

Treatment Technologies of Household Greywater

The shortage of water resource in the developing countries induced the search for alternative sources. Greywater alongside storm and ablution water might represent the best source of water because these waters have less contaminant than sewage. However, the separation of this water from the source point is the first step in the proper management which facilitates the treatment process. The selection of treatment technologies for greywater depends on the economic status and standards limits required for disposal or reuse of greywater which differs from one country to the others. In many of the developing countries, the treatment of greywater aims at achieving the basic requirements which lie in the reduction of the main parameters of greywater. The utilisation of flocculation and coagulants process might be effective for this purpose. Many of the natural coagulants have been reported to reduce the main parameters of greywater. In the developed countries, advanced technologies are used for removing of xenobiotics organic compounds (XOCs) and to produce high quality of the treated greywater. This chapter focuses on the treatment technology used for the treatment of greywater and their efficiency in the reduction of XOCs.