Roughing Filter Research Articles

Modernization of the fuel system of diesel engine of agricultural tractor

The decrease in fuel systems reliability depends mostly on the fuel contamination. To solve the problem, an improved scheme of fuel system is proposed, it includes a fuel preheater and a rough filter of new design. A new design of rough filter is developed, it has a coiled filter element with the improved purification efficiency and good replacement life due to the effective spreading of porosity of filter material by means of its aimed crimping. This allows to reduce evenly the porosity in the direction of fuel stream and to increase the replacement life. The operational tests of improved fuel systems were performed on the basis of agricultural enterprises of the Tomsk region. The MTZ-82 agricultural tractor was chosen as subject of research. The working capacity of fuel system elements in regular and improved versions was evaluated by determining the numeral characteristics of random distribution of mean lifetime and parameters of reliability. Based on test results, the functions of distribution of probability of failure-free operation of the fuel injection pump plungers, the couple of injection jets, the injector spray nozzles of regular and improved diesel fuel systems are constructed. The study reveals that the improved version of fuel system decreases the failure rate of parts by 1.7-2.2 times in comparison with the regular one. It proves that the reliability is improved by means of reducing of contamination through the heated rough filter. The obtained results show the substantial improvement of fuel system reliability with the use of new rough filter.

A Cyclic Frequency Tracking Loop for Wideband Spectrum Sensing and FM Demodulation

A cyclostationary feature-based wideband spectrum sensing is proposed in which cyclic frequency offset is considered. The received signal passes through a rough and flexible filter which its effective band tuned to a specific part of the received signal spectrum. It belongs to a target signal, which possibly exists in the received signal. Some cyclic frequencies of the target are employed to derive the normalized least mean square algorithm that estimates the filter output from its frequency shifted samples. Based on the weight estimate’s norm, the algorithm is tuned to find the accurate cyclic frequencies. If it succeeded, it means that the target signal is present. On the other hand, a complete search without major weights estimate means that the target signal is absent. In addition, the overall system, named cyclic frequency lock loop can be reformed as a demodulator for sinusoidal frequency modulation signals. The method is very easy to implement and has less computational complexity comparing with its other spectrum sensing counterparts. Simulation results validate the efficiency of the proposed method.

Scalants removal from synthetic RO brine using natural zeolite

Membrane distillation (MD) is the thermally driven water separation process based on the vapor pressure difference across the membrane. In order to increase the water recovery of the conventional RO process, the additional MD-PRO pocess was suggested. In this study, the syntheric RO brine was used as a feed solution of the MD process. Due to the high salinity of the RO brine, the MD membrane could be fouled by the scalants. In order to mitigate the scaling on the MD membrane surface, the pre-treatment process using the column filled by natural zeolite was applied. The roughing filter was installed between the pre-treatment process and MD system in order to prevent possible particulate fouling by the debries of the natural zeolite. Moreover, in order to enhance the CEC of the natural zeolite, the NaCl soaking was conducted. The flux and electronic conductivity were monitored under given experimental conditions. And the membrane morphology and the chemical compositions were analyzed by using the SEM-EDX.

Removal of Iron and Manganese Using Cascade Aerator and Limestone Roughing Filter

Combination between oxidation and filtration can be used for removing iron and manganese from groundwater especially when the concentrations of these metals were high. This study focused on the effectiveness of the cascade aerator and the size of the limestone filter media to remove iron and manganese from groundwater. Water samples used for this study were collected from orphanage home, Rumah Nur Kasih, Taiping. Universiti Sains Malaysia (USM) has provided a tube well of 15 m depth and 150 mm diameter for the orphanage home. However, the water cannot be used for domestic consumption due to high amount of iron and manganese at 6.48 and 1.9 mg/L which exceeded the drinking water standard of 0.3 and 0.1 mg/L respectively. Using laboratory physical model, the study has shown that the removals of iron and manganese have reduce the concentration until 0.17 and 0.2 mg/L respectively. Thus, the results from this study which utilize cascade aerator and limestone roughing filter could be implemented on site for the community to use the ground water for domestic purposes.

Removal of Iron and Manganese Using Cascade Aerator and Limestone Roughing Filter

Combination between oxidation and filtration can be used for removing iron and manganese from groundwater especially when the concentrations of these metals were high. This study focused on the effectiveness of the cascade aerator and the size of the limestone filter media to remove iron and manganese from groundwater. Water samples used for this study were collected from orphanage home, Rumah Nur Kasih, Taiping. Universiti Sains Malaysia (USM) has provided a tube well of 15 m depth and 150 mm diameter for the orphanage home. However, the water cannot be used for domestic consumption due to high amount of iron and manganese at 6.48 and 1.9 mg/L which exceeded the drinking water standard of 0.3 and 0.1 mg/L respectively. Using laboratory physical model, the study has shown that the removals of iron and manganese have reduce the concentration until 0.17 and 0.2 mg/L respectively. Thus, the results from this study which utilize cascade aerator and limestone roughing filter could be implemented on site for the community to use the ground water for domestic purposes.

Manganese removal by hydrogen peroxide and biofiltration

Biofiltration has gained more attention as an alternative filtration for the removal of manganese (Mn) in both groundwater and surface water. This study investigated the potential of biofiltration as pretreatment at the Bennery Lake Water Treatment Plant located in Halifax, Nova Scotia, for the removal of manganese and dissolved organic carbon (DOC) from pH 6 natural lake water. A bench-scale study identified the effect of oxidant enhancement with hydrogen peroxide (H2O2), nutrient enhancement with phosphorus (P) and medium type (granular activated carbon (GAC) and anthracite) on a biofiltration system. Addition of both the nutrient, phosphorus (300–500 µg/l), and the oxidant, hydrogen peroxide (0·5 mg/l) enhanced the biofiltration performance, achieving 98% manganese removal and 27% (1·3 mg/l) DOC removal. Overall, the medium was not a significant factor for manganese removal, while GAC removed significantly more DOC than anthracite, although further treatment would be required for either medium to achieve lower DOC concentrations. These results show direct biofiltration of surface water at pH 6 can remove manganese below the 50 µg/l aesthetic guideline from a manganese loading of over 1 mg/l. This work highlights a potential mechanism and implication of biological roughing filtration technique for the removal of manganese and DOC from natural surface water.

Correlation modeling between process condition of sandblasting and surface texture: A multi-scale approach.

In the present study, the influence of sandblasting condition (working pressure) on surface texture is modeled, relying on a multi-scale approach and statistical analysis. To improve the correlation modeling between the process condition and surface texture, special effort is made to identification of an optimal parameter set, including 3D roughness parameters, cut-off lengths, filter types and model types. A power law relationship is identified between the pressure and Sdq computed with a cut-off length of 120 µm using a low-pass filter. Experimental and theoretical arguments are provided for justification. SCANNING 38:191-201, 2016. © 2015 Wiley Periodicals, Inc.

Nitrogen and phosphorous removal from aerated lagoon effluent using horizontal roughing filter (HRF)

Traditionally, aerated lagoons are not reliable wastewater treatment systems to eliminate nutrient contents of municipal wastewater. This study aimed to enhance the aerated lagoon effluent quality by applying a simple filtration system. Removal of nitrogen and phosphorous from aerated lagoon effluent using horizontal roughing filter (HRF) was investigated. Also, the “1/3–2/3 theory” was applied to predict the TSS concentration of HRF effluent. An experimental setup of HRF was used to receive the continuous effluent from wastewater treatment plant. HRF was operated at three consecutive filtration rates, including 0.5, 1 and 1.5 m3 m−2 h−1. At the first filtration rate (0.5 m3 m−2 h−1), the removal efficiencies of total Kjeldahl nitrogen, total phosphorous, TSS, and COD were reported 50, 54, 63, and 68%, respectively. Decreasing the removal efficiency was occurred during raising the filtration rate (p < 0.05). Applying the “1/3–2/3 theory” revealed the significant correlation between predicted and measured TSS values. The capacity of HRF to retain nitrogen, phosphorous, and COD during the filtration runs was 24.3, 10.1, and 435.4g m−3 d−1, respectively. HRF can be applied as an appropriate alternative for tertiary treatment of the aerated lagoon effluent.

Upgrading the effluent quality of an aerated lagoon with horizontal roughing filtration

Upgrading the effluent quality of an aerated lagoon with horizontal roughing filtration

Characterization and treatment of flour mills wastewater for reuse – a case study of Al-kausar Flour Mills, Pakistan

Pakistan is increasingly confronted with shortage of fresh water resources, as annual per capita water availability has reduced to less than 1,000 m3. Wastewater reclamation and reuse practices must be adopted to deal with the situation. For this purpose, small and medium scale industries can play a vital role. With this mind set, wastewater from Al-Kausar Flour Mills Islamabad (AFM), Pakistan was investigated using physico-chemical treatment options. Total water consumption of AFM is 74.1 m3/d, and groundwater is being pumped for 8 h/d. Four experimental trains were tested using various combinations of pre-sedimentation, horizontal roughing filter, coagulation/flocculation/settling setup, and multimedia filtration. Ferric chloride and alum were used as coagulants. Results revealed that flour mill wastewater had high concentration of total suspended solids. Ferric chloride provided appreciable suspended solids removal in terms of turbidity. While, every option tested, removed over 98% of turbidity but option C, with 25 mg/L ferric chloride dosage, produced effluent fit for water reuse in the industry. It was also evaluated that AFM could save up to PKR 83,500.0 (US $800) in terms of energy cost and ground water volume of at least 1.6 ML per year.

Using Horizontal Roughing Filter as an Effective Post-Treatment System for Palm Oil Mill Effluent (POME): Effect of Media Sizes and Filtration Rates

In this study, palm oil mill effluent (POME) from polishing pond of palm oil mill treatment plants has been chosen to be treated in laboratory experiment using horizontal roughing (HRF) filter system. The purpose of this article was to evaluate the effect of three filter media sizes on the removals of COD, NH3-N and turbidity and as well as to evaluate the effect of three filtration rates on the removal of color, turbidity and suspended solid from POME using limestone media in HRF system. The results indicated that the removal of smaller filter media gave higher removal efficiency and larger size of filter media gave lower removal efficiency. Optimum removal of COD, NH3-N and turbidity were 27%, 51% and 32%, respectively, which were obtained at lowest filter media size (i.e. 3-6 mm). Similar result was also obtained in studying the effect of filtration rates. It was found that the optimum reduction of turbidity, suspended solid and color were up to 38.6%, 57.4%, and 34.5%, respectively, at lowest filtration rates of 0.3 m h-1. These results were supported by one-way analysis of variance (ANOVA). Keywords: Color, removal of COD, NH3-N, suspended solid, turbidity.

Experimental study on the performance of a rotational supercavitating evaporator for desalination

Efforts have been made on experimental research of a supercavitation device for desalination, which is named rotational supercavitating evaporator (RSCE). The RSCE is characterised by the simple construction and responsive capacity control, and only requires rough filtration of the source water for scaling- and fouling-free operations. The present study has been conducted for the water flow at temperature of around 22–30°C and atmospheric pressure as the first step for investigation of the performance characteristics of RSCE. The multiply factor extremal experiments conducted with the Box-Wilson’s method have revealed the salinity of the condensate, the temperature of steam inside the supercavity, and dependence of the shape of supercavity on the rate of steam extraction and rotation speed of impeller. The shape of impeller and the expected supercavitating effects it generates have been confirmed by experimental results at the rotation speed of 5430 rpm (round per minute). The design of the steam extraction openings has been approved during the evacuation of steam. The experimental dependencies have been obtained in form of statistically valid regression equations, which can be used for engineering design of RSCE.

The use of vertical constructed wetland and ultrasound in aquaponic systems

Treatment performance, fish production, crop plant biomass production, water consumption, and water use efficiency of a pilot aquaponic system for small-scale land-based cyprinid fish farms were evaluated. The system consisted of a 36 m(3) Pond A with an initial carp load of 0.6 kg/m(3); of a treatment chain with a lamellar settler, a roughing filter, a vertical constructed wetland filled with expanded clay and planted with tomatoes; and of a low power ultrasound unit installed in the corner of the pond. The average circulation of the water in the system was 1.2 times per day. Pond A was compared with Pond B of the same dimensions and fish load but with no treatment chain or ultrasound. The treatment chain was efficient in mass removal of total suspended solids , biochemical oxygen demand, chemical oxygen demand, NH4-N, total nitrogen, and total phosphorous (57, 49, 35, 42, 31, and 25 %, respectively). Negative removal of NO3-N, NO2-N, and PO4-P indicated the need for the introduction of additional hydroponic beds in the system. Pond A had markedly lower nutrient concentrations compared with Pond B. Fish body weight increase and specific growth rate in Pond A were higher than in Pond B (102.6 %, 72.1 %; 0.19 %/day, 0.14 %/day, respectively) indicating better rearing conditions in Pond A. Tomato biomass production was high. Water use efficiency was higher in Pond A compared with Pond B (0.31 kg of produced fish/m(3) inflow water and 0.22 kg of produced fish/m(3) inflow water, respectively). The presented aquaponic system could be useful for semi-natural fish farming with fish loads up to 2 kg/m(3).

Determination of shear surface of landslides using electrical resistivity tomography

Abstract Geophysical methods offer a broad spectrum of information by dealing with slope deformations. The electrical resistivity tomography (ERT) method is mainly applied for spatial localization of the landslide body and depicting the shear zone position. This article presents the application of the ERT method for the landslide hazardous areas by means of numerical modelling. Four different synthetic models with very small resistivity contrast (30 Ohm.m/50 Ohm.m), where each model represents a different type of slope deformation, were tested by several factors affecting the final inverse model: measurement point density, L1 and L2 norm and L-norm roughness filter components. The higher measurement points density helps mainly to detect the boundaries at greater depths. Inverse models computed using the L1 norm bring satisfactory results for compact anomalous bodies, i.e. water saturated landslide body. In the case of subtle conductive zones, i.e. shear planes, the L2 norm based inversion is recommended. For enhanced reconstruction of skewed anomalous objects, roughness filter including a diagonal component produces more accurate inverse image. The article also demonstrates the ability of the ERT method to detect and describe the shape of the slope deformation even by a relative subtle resistivity contrast

Treatment of high turbidity water through plain and coagulated up-flow roughing filter

Khokhar Zar Dam in Chakwal, Pakistan, serves as a main source of water supply to the area. This water is not only turbid but also biologically polluted. A hybrid slow sand filtration (SSF) plant, involving coagulation and sedimentation prior to SSF, is employed for the treatment. The treatment train is sensitive to wide variations in raw water turbidity and often results into short filter runs. Major objective of this research was to study the existing treatment process and conduct a pilot-scale investigation for the most appropriate treatment scheme, using an up-flow multistage roughing filter. A three-stage up-flow roughing filter (UFRF) was tested in plain and coagulated mode for a range of flow rates. Results showed that raw water turbidity reduced to 30 NTU in dry period and rose to over 2000 NTU after rainfall, whereas raw water pH and conductivity remained consistent. Jar tests showed that higher FeCl3 dose (65 mg/L) would be required when compared with alum (47 mg/L). Plain multistage UFRF demonstrated 30–50% turbidity removal, whereas coagulated UFRF showed 99% turbidity removal at 35% of the dose applied by the treatment plant. Effectiveness of coagulated filtration continued even after the dose supply was ceased.

Study on Integrated System of SCR and Muffler for Heavy-Duty Diesel Vehicle

SCR (Selective Catalytic Reduction) is widely used as a good solution of reducing NOx emissions. For NOx emissions and exhaust noise for heavy-duty diesel vehicles, the paper studied the acoustic performance for the integrated system of SCR and muffler. By analyzing the action of the perforated pipe, the exhaust pressure loss and the impact on the performance of the integrated system, the integrated system was developed for heavy-duty diesel vehicles to solve the technical problem on the integration and performance optimization for the SCR system and muffler structure. Extrusion-type vanadium-based catalyst replaces the current coated-type catalysts, and improves the reduction efficiency. The two-stage rough and fine filter and the heating device for the urea pump are designed to increase the adaptability of the SCR system. The research shows that through the structural improvements, the exhaust noise is reduced by 28.5dB.

OPERATIONAL PERFORMANCE OF VERTICAL UPFLOW ROUGHING FILTER FOR PRE-TREATMENT OF LEACHATE USING LIMESTONE FILTER MEDIA

This study was conducted to investigate the removal of COD, BOD, turbidity and colour from leachate using vertical upflow filtration technique. Limestone media with a density of 2554kg/m3 was crushed and graded in sizes of 4-8 mm, 8-12 mm and 12-18 mm. Trial runs were done before the main experiment at an interval of 24 h analysis. Leachate was between pH 7.94 to 8.12 before experiments but increased to pH 8.42 after the filtration process. Maximum headloss at steady flow rate 20mL/min was 0.5 cm. The optimum treatment was achieved with 4 – 8 mm, 8 – 12 mm &amp; 12 – 18 mm media size in combination and removal efficiency was 22 to 81 %, 22 to 75 %, 32 to 86 %, and 36 to 62 % for BOD, COD, turbidity and colour respectively. Vertical upflow roughing filter can be used for pre-treatment of leachate before further treatment.

OPERATIONAL PERFORMANCE OF VERTICAL UPFLOW ROUGHING FILTER FOR PRE-TREATMENT OF LEACHATE USING LIMESTONE FILTER MEDIA

This study was conducted to investigate the removal of COD, BOD, turbidity and colour from leachate using vertical upflow filtration technique. Limestone media with a density of 2554kg/m3 was crushed and graded in sizes of 4-8 mm, 8-12 mm and 12-18 mm. Trial runs were done before the main experiment at an interval of 24 h analysis. Leachate was between pH 7.94 to 8.12 before experiments but increased to pH 8.42 after the filtration process. Maximum headloss at steady flow rate 20mL/min was 0.5 cm. The optimum treatment was achieved with 4 – 8 mm, 8 – 12 mm &amp; 12 – 18 mm media size in combination and removal efficiency was 22 to 81 %, 22 to 75 %, 32 to 86 %, and 36 to 62 % for BOD, COD, turbidity and colour respectively. Vertical upflow roughing filter can be used for pre-treatment of leachate before further treatment.

Smoothness‐constrained time‐lapse inversion of data from 3D resistivity surveys

ABSTRACTThree‐dimensional resistivity surveys and their associated inversion models are required to accurately resolve structures exhibiting very complex geology. In the same light, 3D resistivity surveys collected at multiple times are required to resolve temporally varying conditions. In this work we present 3D data sets, both synthetic and real, collected at different times. The large spatio‐temporal data sets are then inverted simultaneously using a least‐squares methodology that incorporates roughness filters in both the space and time domains. The spatial roughness filter constrains the model resistivity to vary smoothly in the x‐, y‐ and z‐directions. A temporal roughness filter is also applied that minimizes changes in the resistivity between successive temporal inversion models and the L‐curve method is used to determine the optimum weights for both spatial and temporal roughness filters. We show that the use of the temporal roughness filter can accurately resolve changes in the resistivity even in the presence of noise. The L1‐ and L2‐norm constraints for the temporal roughness filter are first examined using a synthetic model. The synthetic data test shows that the L1‐norm temporal constraint produces significantly more accurate results when the resistivity changes abruptly with time. The model obtained with the L1‐norm temporal constraint is also less sensitive to random noise compared with independent inversions (i.e., without any temporal constraint) and the L2‐norm temporal constraint. Anomalies that are common in models using independent inversions and the L2‐norm and L1‐norm temporal constraints are likely to be real. In contrast, anomalies present in a model using independent inversions but that are significantly reduced with the L2‐norm and L1‐norm constraints are likely artefacts. For field data sets, the method successfully recovered temporal changes in the subsurface resistivity from a landfill monitoring survey due to rainwater infiltration, as well as from an experiment to map the migration of sodium cyanide solution from an injection well using surface and borehole electrodes in an area with significant topography.

Comparing plain and coagulated horizontal flow roughing filtration for high turbidity water

In this work, a multi-compartment, horizontal flow roughing filter (HRF) was designed, constructed and operated to evaluate its effectiveness against high turbidity surface water with and without coagulation. The objective was to evaluate the efficacy of the HRF in removing turbidity, total organic carbon (TOC), total coliform and particulate matter. The HRF was operated at filtration rates of 1.3, 1.0 and 0.7 m/hr. At 0.7 m/hr, plain HRF (PRF) reduced turbidity by 35%, TOC by 31%, coliform by 90% and particles with average diameter &amp;gt;4 μm. For coagulated roughing filtration (CRF), the optimum alum dose of 110 mg/L (L100) was determined using jar tests. In-line, CRF of the raw water using 25% (L25) and 50% (L50) of L100 reduced turbidity by 87 and 98%, respectively. TOC removal at L50 was 41% and total coliform removal up to 99%. CRF was more effective in removing particles with average diameter &amp;gt;1 μm. CRF did not only help attenuating the turbidity shock loads but also consistently produced high quality effluent of 5–10 NTU at 55 mg/L vs 176 mg/L used by the plant. Over 98% reduction in coliform and removal of most particles of &amp;gt;1 μm diameter demonstrated that CRF would also be effective in removal of protozoa such as Giardia.