Showing papers by "Zaini Ujang published in 2019"

Patterns and Causes of Food Waste in the Hospitality and Food Service Sector: Food Waste Prevention Insights from Malaysia

Abstract: Food waste has formidable detrimental impacts on food security, the environment, and the economy, which makes it a global challenge that requires urgent attention. This study investigates the patterns and causes of food waste generation in the hospitality and food service sector, with the aim of identifying the most promising food waste prevention measures. It presents a comparative analysis of five case studies from the hospitality and food service (HaFS) sector in Malaysia and uses a mixed-methods approach. This paper provides new empirical evidence to highlight the significant opportunity and scope for food waste reduction in the HaFS sector. The findings suggest that the scale of the problem is even bigger than previously thought. Nearly a third of all food was wasted in the case studies presented, and almost half of it was avoidable. Preparation waste was the largest fraction, followed by buffet leftover and then customer plate waste. Food waste represented an economic loss equal to 23% of the value of the food purchased. Causes of food waste generation included the restaurants’ operating procedures and policies, and the social practices related to food consumption. Therefore, food waste prevention strategies should be twofold, tackling both the way the hospitality and food service sector outlets operate and organise themselves, and the customers’ social practices related to food consumption.

Development of aerobic granules in sequencing batch reactor system for treating high temperature domestic wastewater

Abstract: The application of aerobic granular sludge (AGS) in treating real domestic wastewater at high temperature is still lacking. In this study, the microstructure and morphology of the granules, as well as bioreactor performance, were investigated during the treatment of real domestic wastewater at high temperature (50 °C). The experiment was executed in a sequencing batch reactor (SBR) with a complete cycle time of 3 hours for the treatment of low-strength domestic wastewater at an organic loading rate (OLR) of 0.6 kg COD m −3 d −1 . Stable mature granules with average diameters between 2.0 and 5.0 mm, and good biomass concentration of 5.8 g L−1 were observed in the bioreactor. AGS achieved promising results in the treatment of domestic wastewater with good removal rates of 84.4 %, 99.6 % and 81.7 % for chemical oxygen demand (COD), ammoniacal nitrogen (NH 3 −N), and total phosphorus (TP), respectively. The study demonstrated the formation capabilities of AGS in a single, high and slender column type-bioreactor at high temperature which is suitable to be applied in hot climate condition areas especially countries with tropical and desert-like climates.

New entry point of membrane technology for public water treatment plants in Malaysia

Abstract: Membrane applications in public water treatment plants (WTP) in Malaysia have seen more setbacks than successes. Its early applications in a few locations encountered operational problems which saw many systems cease operations due to high operating expenses, membrane fouling or poor raw water quality. The main issue, however, was financial-related in view of the fact that the water tariff has been regulated and heavily subsidised. Both capital expenses (CAPEX) and operating expenses (OPEX) have not been affordable within such a framework. The power consumption of a 3 million L d–1 (MLD) hybrid membrane WTP subjected to study consumed 1.5 kWh m–3 of electricity as compared with 0.43 kWh m–3 for a conventional system in the same district. Besides that, cartridge filters had to be changed on a weekly basis as compared with filter media which can last more than 5 years. Capital cost of a membrane WTP is at least twice more expensive than conventional systems. Based on the standard of raw water adopted in the Malaysia, it is imperative that operators raise raw water quality standards prior to treatment whether through natural process or forced, physically or chemically. Downstream reservoir, river bank infiltration and radial well system have been applied in several projects in Malaysia and had successfully resulted in the high quality of raw water. However it has always been restricted from being implemented holistically due to financial constraints. Hybrid offriver storage implemented as interim measure to improve raw water quantity had indicated prospect of improving raw water to reach higher standards. This paper compares the raw water quality of various non-conventional raw water abstractions, followed by discussion on the proposed entry point of membrane systems in Malaysia for public WTPs.