Palm oil production is one of the major industries in Malaysia and this country ranks one of the largest productions in the world. In Malaysia, the total production of crude palm oil in 2008 was 17,734,441 tonnes. However, the production of this amount of crude palm oil results in even larger amounts of palm oil mill effluent (POME). In the year 2008 alone, at least 44 million tonnes of POME was generated in Malaysia. Currently, the ponding system is the most common treatment method for POME but other processes such as aerobic and anaerobic digestion, physicochemical treatment and membrane filtration may also provide the palm oil industries with possible insights into the improvement of POME treatment processes. Generally, open ponding offers low capital and operating costs but this conventional method is becoming less attractive because the methane produced is wasted to the atmosphere and the system can not be certified for Carbon Emission Reduction trading. On the other hand, anaerobic digestion of POME provides the fastest payback of investment because the treatment enables biogas recovery for heat generation and treated effluent for land application. Lastly, it is proposed herewith that wastewater management based on the promotion of cleaner production and environmentally sound biotechnologies should be prioritized and included as a part of the POME management in Malaysia for attaining sustainable development. This paper thus discusses and compares state-of-the-art POME treatment methods as well as their individual performances. 相似文献
Karoon River, from Gotvand Dam to Persian Gulf with more than 450 km in length and an annual discharge of 11,891 million cubic
meters, is the largest river in Iran. Increasing water withdrawal from and wastewater discharge to the river has endangered
the aquatic life of this important ecosystem. Furthermore, the drinking and in-stream water quality standards have been violated
in many instances. In this paper, a river water quality monitoring network is designed, including determination of sampling
frequencies as well as location of water quality monitoring stations. In this regard, two models are developed. The first
model is a Genetic Algorithm-based optimization model and the second one is a combination of Kriging method and Analytical
Hierarchy Process. The temporal variation of the concentration of water quality variables along Karoon and Dez Rivers are
evaluated and the main water quality indicators are selected. Then, thirty five stations are selected and the application
of Entropy Theory in calculating the sampling frequency is demonstrated. The results show the significant value of the proposed
methodology in the design of monitoring network. 相似文献
Efficient use of energy helps to achieve increased production and productivity and contributes to the economy, profitability, and competitiveness of agricultural sustainability of rural communities. Evaluation of wheat and barley production systems in view of energy balance was conducted in Khorasan Razavi Province, Iran. Data were collected by using a face-to-face questionnaire from wheat and barley fields in 2011. Results revealed that total energy input for wheat was 51,040 MJ ha?1 and for barley 44,866; in wheat and barley systems, renewable energy was consumed by 25.43 and 23.53 %, while non-renewable energy was consumed by 74.57 and 76.47 %, respectively. Energy use efficiency, energy productivity, and net energy were 1.7 kg MJ?1, 0.088 kg MJ?1, and 35,987 MJ ha?1 in wheat system and 1.83 kg MJ?1, 0.092 kg MJ?1, and 33,833 MJ ha?1 in barley system, respectively. Energy intensiveness in wheat fields (61.84 MJ $?1) was higher than in barley fields (58.71 MJ $?1). Also, benefit-to-cost ratio in wheat system (1.59) was higher than in barley system (1.35). In general, production in barley fields was more sustainable than wheat production because, in view of ecological indices such as amount of energy use and renewable energy consumption, it was more environment-friendly production. 相似文献
Manual material handling (MMH) tasks can be found in most workplaces and they may constitute a risk factor for work-related musculoskeletal disorders (WMSDs). This study was conducted to determine the prevalence of WMSDs and to compare MMH loads with the acceptable weight and force limits among Iranian casting workers. Data were collected from 50 workers of casting workshops who performed MMH tasks. The Nordic musculoskeletal disorders questionnaire and the Snook tables were used as tools for data collection. Hand/ wrist symptoms were the most prevalent problems among the workers (84%). The results of the Snook tables showed that the loads in lifting (84%), lowering (86%), carrying (66%), pushing with initial (43%) and sustained force (59%), and pulling tasks with initial (48%) and sustained force (93%) exceeded recommended limits. WMSDs occurred in high rates among the workers and, thus, ergonomics interventions should focus on decreasing WMSDs and redesigning MMH tasks. 相似文献
Background. Work-related musculoskeletal disorders (WMSDs) are injuries and disorders that affect the body’s movement and musculoskeletal system. Awkward postures represent one of the major ergonomic risk factors that cause WMSDs among sonographers while working with an ultrasound transducer. This study aimed to design and evaluate a new holder for the ultrasound transducer. Materials and methods. In the first phase a new holder was designed for the transducer, considering design principles. Evaluation of the new holder was then carried out by electrogoniometry and a locally perceived discomfort (LPD) scale. Results. The application of design principles to the new holder resulted in an improvement of wrist posture and comfort. Wrist angles in extension, flexion, radial deviation and ulnar deviation were lower with utilization of the new holder. The severity of discomfort based on the LPD method in the two modes of work with and without the new holder was reported with values of 1.3 and 1.8, respectively (p?<?0.05). Conclusion. Overall, this study indicated that applying ergonomics design principles was effective in minimizing wrist deviation and increasing comfort while working with the new holder. 相似文献
Journal of Material Cycles and Waste Management - The extraction of unsustainable natural resources like sand and topsoil for construction is disturbing ecological balance, affecting local... 相似文献
Nowadays, the importance of green and biodegradable plastics as viable substitutes for non-degradable petroleum-based materials is felt more than ever. Regenerated cellulose (RC) as a potential candidate suffers from poor processability and inferior properties, limiting its wide applications. In this study, it is demonstrated that citric acid (CA) enhances physical, mechanical, and thermal properties of RC films, due to RC-citric acid compatibility. 1-ethyl-3-methylimidazolium chloride (EMIMCl) as a green ionic liquid was employed for the processing of RC. The optimum properties in terms of thermal stability, mechanical strength, contact angle, water uptake, and oxygen permeability were achieved at 10 wt% of CA. However, further incorporation of CA adversely affected the film properties. This behaviour was explained by the crosslinking and plasticizing effects of CA. Furthermore, in vitro cytotoxicity test demonstrated that RC/CA films are cytocompatible, suggesting the potential advantage of using these biopolymeric films for biomaterial and biological applications.
Journal of Polymers and the Environment - In this study, composite packaging films were produced from relatively inexpensive materials including Whey protein isolate (WPI) and Persian gum (PG),... 相似文献
Journal of Polymers and the Environment - The present work presents an analysis of the tensile properties of Palm as well as Luffa natural fiber composites (NFC) in high density polyethylene... 相似文献
Environmental Science and Pollution Research - Iran’s agricultural production has expanded significantly in recent years. Environmental pollution caused by the use of energy and chemical... 相似文献