Effect of PrekotAc on pressure drop and particle penetration in filtration system

The effect of a filter aids known as PrekotAC on pressure drop and particle penetration in a filtration system with varying filtration velocity of 1 to 5 m/min was evaluated in this study. The PrekotAC is a combination of PrekotTM and activated carbon mixed in different weight composition. The result showed that the pressure drop across the fabric media decreases with the addition of PrekotTM in the PrekotAC admixture due to its wide range of non-uniform particle size ditribution that gives higher porosity of filter cake during filtration process. The study also showed that the total particle penetration through the fabric media was proportionally related to addition of PrekotTM in the PrekotAC admixture under a constant material loading. The study suggests that the addition of PrekotTM in the formulation of filter aids significantly affect both pressure drop and penetration of the fabric filter media

Performance of prekotac filter aids in pilot plant fabric filtration system

Filter aids is used in air filtration system to fulfil the needs to expand the life span of filter media in fabric filtration system. It has been applied in various ways and precoat filter aids is one of the methods. In this study, the effect of a filter aids performance known as PrekotAC on pressure drop and particle penetration in a filtration system with varying filtration velocity of 1 to 3 m/min was evaluated. The PrekotAC is a combination of PrekotTM and activated carbon mixed in different weight compositions. Result showed that the pressure drop across the fabric media decreases with the addition of PrekotTM in the PrekotAC admixture due to its wide range of non-uniform particle size distribution that gives higher porosity of filter cake during filtration process. The study also showed that the total particle penetration through the fabric media was proportionally related to addition of PrekotTM in the PrekotAC admixture under a constant material loading. The study suggests that the addition of PrekotTM in the formulation of filter aids significantly affect both pressure drop and particle penetration of the fabric filter media

Penetration of particle across a newly formulated filter aids material

Filter aids is a group of inert materials acting as a ‘barrier’ for protection as well as to allow a uniform air flow passing through a filter cake in a filtration process. In addition, the accumulation of the filter cake deposited on the surface of the filter media helps to increase the performance of filtration. However, some particles do not participate in the formation of the filter cake during cake filtration process. The particles either penetrating through the filter media or clog and block the pores of the filter medium. A high performance filtration requires low dust penetration without excessive pressure drop builds up across the filter media. This paper evaluates on the filtration performance of a newly formulated filter aids material known as PrekotAC which consists of different combination of pre-coating material PrekotTM and activated carbon at material loadings of 0.2 mg/mm² under different air flow rates of 4, 5, and 6 L/min. The PrekotAC was evaluated based on the total particle penetration across its filter cake as a mean of measuring its performance. The study showed that the total particle penetration through the filter media is highly influenced by the air flow rates. It was found that the total particle penetration through PrekotAC10:90 (weight basis of PrekotTM:activated carbon) was the lowest while the highest in the case of PrekotAC 40:60 of the four PrekotAC admixtures. In addition, the total particles penetrating through the filter media was the highest for the highest tested air flow rates of 6 L/min

Performance of a newly formulated filter aids material on particle penetration

A study on the penetration of particle across a newly formulated filter aids material known as PrekotAC (combination of an adsorbent, activated carbon and pre-coating material, PreKot™) on PTFE filter media was carried out in a laboratory scale filtration test system. PrekotAC was evaluated based on the total penetrated particles across its filter cake under constant material loading of 0.2 mg/mm² and three different air flow rates of 4, 5 and 6 L/min. The ratio of total penetrated particles with and without the introduction of filter aids was observed and results showed that PrekotAC is capable to increase the collection efficiencies of ambient air particles compared to the performance of PTFE filter media alone. It was also found that PrekotAC has a better particle collection efficiencies compared to its original raw material activated carbon alone with PrekotAC 10:90 gives the lowest particle penetration among other combination of PrekotAC materials

Prekotac as a new filter aids material for fabric filter in air filtration system

Fabric filter has a short life span due to wear and tear influenced by the operating conditions of the system. Treatment of fabric filter using pre-coating material is one of the simplest technique to overcome this problem where it works as a filtration aids that will coat a layer of inert material onto the surface of the fabric. Pre-coating acts as a barrier to block and remove undesired particles from gas stream but allowing a uniform air flow passing through the filter media. The morphology of dust cake that accumulated on the surface of the filter media depends on several properties of the particles such as shape and size. Hence, study presents the characterization of a newly formulated filtration aids known as PrekotAC consisting of a different combination of pre-coating material PreKot™ and activated carbon. The aim is to determine the best combination of PrekotAC admixtures as a filtration aids suitable for a fabric filtration system. Various characteristics of the formulated admixtures such as its particle size distribution, bulk density, moisture content as well as its morphology were investigated and presented in this paper

An agricultural investment map based on geographic information system and multi-criteria method.

The study aimed to produce an investment classification map, which shows the potential areas of investment in agriculture in Sinnar, Sudan. The spatial multi-criteria analysis was used to rank and display potential locations, while the analytical hierarchy process method was used to compute the priority weights of each criterion. The study attempted to explore the utilization of Geographic Information System (GIS) to map the potential investment areas, therefore, it did not cover a comprehensive analysis of all factors that influence investment in agriculture. In addition, the analysis was limited to criteria that had spatial reference. The investment criteria for spatial analysis were defined from the guidelines provided by the Ministry of Investment, Sudan. Even with the shortcomings of the data, it was found that the results obtained were very encouraging and provided clear indicative areas for agricultural investment in Sinnar. Government agencies can use GIS to access information regarding the potential areas of investment, and minimize investment risks. On the other hand, the economic development organizations will now have the ability to benefit from the Geographic Information System (GIS) solutions by leveraging on this technology to attract and retain business from worldwide sources. Thus, the model will serve as a decision support tool for investors and decision makers at various levels

Deformable unsaturated laterite soil under vibration impact with dissimilar moisture content

Vibrations from vehicle traffic, machinery and operations from construction activities such as blasting are examples of some natural and man-made vibration phenomenon's that can cause dynamic stress when imposed onto soils. In order to ensure sustainability of the geo-environment, the impacts caused by these vibrations as well as the changes in moisture content needs to be addressed. To achieve this, the behaviour of vibrated deformable double-porosity under dissimilar moisture content in non-repeated vibration was assessed and characterized through laboratory experiments. Investigation of deformable unsaturated laterite soil by aggregating laterite soil using 29%, 30%, 32% and 34% moisture content was carried out and presented in this paper. An acrylic soil column, accelerometer and vibrating table were used to conduct the experiments. The acrylic columns were filled with each aggregated soil and the soil was then compressed to a height of 10 cm, which had been pre-determined beforehand. Accelerometers were installed to a vibrating table where each soil column was tested to measure the time histories of high-frequency acceleration on the surfaces of both the laterite soil and vibrating table. Acceleration was observed at two points, namely; (1) the surface of the soil sample and (2) the surface of the vibrating table. The amplitude of the vibrating table was increased in order to test for repeated vibration. Maximum amplitudes were recorded by collecting the acceleration time histories and the amplitude of displacement was increased in order to carry out the tests. The outcome of the tests demonstrated that there was an increase of the acceleration response in non-repeated vibration when moisture contents were also increased. For the vibrated samples that were used, it was found that there was a rearrangement of the soils structure and as expected, the porosity characteristics that were identified had influenced the liquid penetrations' speed

A cross-sectional study of hypertensive outpatients to determine the necessity of asking about erectile dysfunction symptoms.

Background: Erectile dysfunction (ED) is common amongst hypertensive men. Hypertensive patients often attribute it to antihypertensive drugs, although conflicting evidence linking ED with antihypertensive medication exists. The objectives were to determine the prevalence and severity of ED, the type of treatment sought, and the risk factors for ED among hypertensive men. Method: A cross-sectional survey conducted over six months from June to November 2008 at University Kebangsaan, Malaysia Medical Centre, Kuala Lumpur. Inclusion criteria included hypertensive men above 30 years old, with essential hypertension for at least three months. We excluded diabetics, a history of pelvic surgery and known psychiatric illnesses. The International Index of Erectile Function-5 (IIEF-5) assessment was used with a standardised checklist. We analysed data using SPSS, to assess the prevalence and association of ED with selected variables. Results: Of the 200 participants screened, 35.5% perceived that they had ED. However, prevalence increased to 69% after screening using an IIEF-5 questionnaire. Forty-eight per cent were reported to have moderate-tosevere ED. ED was significantly associated with age (p-value = 0.0001). No significant associations were found between ED and the duration of the hypertension (p-value = 0.505), hypertension control (p-value > 0.05), smoking status (p-value = 0.858) or number of antihypertensive medication taken (p-value > 0.05). Among perceived and proven ED patients, traditional medicines were mainly used for treatment (18.3% and 17.2% respectively). Conclusion: ED is a problem among hypertensive patients. It was associated with age but not with hypertension duration, control, number of antihypertensive drugs or smoking. Physicians should enquire about ED symptoms in hypertensive patients, as most of them resorted to self-treatment with traditional medicines

Methanolysis of duckweed and azolla: A comparative analysis

This paper compares the bio-oil and chemical compositions produced from methanolysis of duckweed and Azolla. The methanolysis was carried out at 230°C, 250°C and 300°C for 30 minutes using the CJF-0.1L reactor. Oil yield produced from azolla was 34% and this is 3% higher as compared to the bio-oil yield produced by duckweed at 250°C. The Gas Chromatography Mass Spectrometry (GCMS) analysis showed that alcohol, ketone, amine, ether and ester compositions in the bio-oil produced from duckweed were slightly higher than azolla. However, carboxylic acids, amide and phenol compounds in the bio-oil produced from azolla are different and higher than duckweed. The results suggest that duckweed and azolla are the potential feedstocks from aquatic biomass to be further investigated for bio oil use