Coal Ash Content Measurement Based on Pseudo-Dual Energy X-ray Transmission

The real-time ash content measurement is the fundamental condition for the timely adjustment and intelligent control of operation parameters in coal production and utilization industry. In the present work, a real-time ash content analyzer based on the pseudo-dual energy X-ray transmission was developed. The feasibility of this X-ray ash content analyzer was validated by the linear relationship between ash content and five characteristic parameters of X-ray. The conditions of wave filter, tube voltage, and tube current were optimized. The comparison between the ash contents measured by muffle furnace and the X-ray ash content analyzer was conducted in laboratory and industry. It was found that the absolute error was smaller than 1% for clean coal with ash content of approximately 10%, and the possibility of the absolute error smaller than 0.5% was higher than 85%.

Influence of Filter Tube of Pumping Well on Groundwater Drawdown during Deep Foundation Pit Dewatering

The partial penetrating waterproof curtain combined with pumping wells is widely applied to deep foundation pit dewatering engineering. The filter tube of the pumping well plays a critical role on the environment effect that resulted from foundation pit dewatering. This paper investigated the impact of the filter tube on the groundwater drawdown outside the pit to provide a theoretical basis for the foundation pit dewatering design. Three patterns according to the relative position of the waterproof curtain and the filter tube, which are called wall-well patterns, namely the full-closed pattern, part-closed pattern, and none-closed pattern, have been analyzed. By taking a practice engineering case in Shanghai as an example, the relationship among the proportion of the filter tube length to the dewatering aquifer thickness, the buried depth difference of the wall-well, and the groundwater drawdown difference at both sides of the waterproof curtain are discussed by numerical simulation. The full-closed pattern is the optimal wall-well pattern on the ideal condition. The suggested and optimal values of the filter tube length to the dewatering aquifer thickness are 38.7% and 58.2%. The suggested and optimal values of the buried depth difference of the wall-well are −6.41 m and −1.92 m.

On-line fault diagnosis model for rigid ceramic filters based on outlet concentration and dynamic pressure

Sudden fractures in rigid ceramic filter tubes hinder the stable long-term operation of advanced power-generation processes. In this study, Time difference of arrival (TDOA) of dynamic pressure in the inner wall of filter during pulse jet cleaning process and outlet concentration with diameter of leakage during filtration and pulse jet cleaning process are investigated using high frequency sensors and optical particle spectrometry. The outlet concentrations measured under different leakage agreed with the theoretical values, with the peak outlet concentration being 2.5 times greater than stable outlet concentration. There is a linear relationship between leakage aperture and theoretical outlet concentration in leaking ceramic filter tubes. A positioning model that can precisely locate the leaking ceramic filter tube using the time difference in the dynamic pressure as measured at different positions is established. This research can quickly and accurately determine whether a ceramic filter tube is broken and location of breakage.

Tuning pi untuk stabilitas kecepatan putaran motor induksi 1 fasa pada mesin penyaring bubur kedelai

Perusahaan tahu di Indonesia pada umumnya, masih menggunakan cara manual, dalam pembuatannya khususnya pada proses penyaringan bubur kedelai yang membutuhkan waktu yang, lama. Hal tersebut didasarkan pada belum ditemukannya mesin pemeras bubur kedelai. Dewasa ini telah ditemukan inovasi mesin, pemeras bubur kedelai yang bisa meningkatkan kuantitas dan, kualitas produksi dibanding dengan cara manual. Penerapan, teknologinya adalah bubur kedelai diletakkan pada tabung, penyaring kemudian tabung tersebut diputar menggunakan motor, yang dihubungkan melalui fanbelt dan pulley. Ketika motor, diputar, tabung akan ikut berputar sehingga menimbulkan gerak, sentrifugal dimana air kedelai akan terpisah dari ampas. Kecepatan putar motor yang dikontrol adalah 750 rpm dengan, nilai Kp 0,108 , Ki 0,83 sehingga mendapatkan air sari kedelai, sebesar 1,3 liter dengan perbandingan 1 kg kedelai : 1 liter air. Parameter dari penerapan metode PI ini meliputi rise time 4 detik, settling time 4,5 detik, overshoot 0 dan error steady state 2,4%. Dengan penerapan metode PI maka hasil perasan kedelai dari, peyaringan menjadi semakin banyak dan waktu yang dibutuhkan 4 menit lebih singkat dibandingkan dengan cara konvensional. Tofu companies in Indonesia generally still use manual methods in their manufacture, especially in the soybean slurry screening process which certainly has many disadvantages such as extortion time needed. This was based on the fact that there was no innovation in the soybean pulp squeezer. Currently, it has been found that innovations of soybean slurry machines can increase the quantity and quality of production compared to manual methods. The application of the technology is soybean slurry placed on the filter tube then the tube is rotated using a motor connected with fanbelt and pulley. When the motor is rotated, the tube will rotate, causing centrifugal motion where the soybean water will separate from the pulp. The speed of the motor controlled in 750 rpm with the Kp 0,108, Ki 0,83, to get soybean essence up to 1,3 liter within comparison 1 kg soybean : 1 liter water. The parameter PI method including rise time 4 second, settling time 4,5 second, overshoot 0 and error steady state 2,4%. By applying PI method, the result of filtering is 4 minute faster comparing with conventional method.

Numerical Simulation of Dust Deposition in the Filter Tube of Adsorption Air Purifier

In recent years, indoor air quality that deeply affected people’s health cannot be ignored. It is affected by many factors, and people have taken many measures to reduce the pollution level. In addition to diluting by controlling pollution sources and using natural ventilation, air purifiers have become one of the choices, but the results are not satisfactory. To improve the dust removal effect of the adsorption air purifier, we established the dynamic equation of PM2.5 concentration under different ventilation modes based on the analysis of indoor PM2.5 concentration change process, the integral and convergent operation of the equation were carried out, and the formula and main influencing factors of indoor PM2.5 concentration in steady state under different ventilation modes were obtained. Meanwhile, the mathematical model of the internal pipeline of the purifier was established by using the Navier-Stokes equation; we selected the DPM model in the software FLUENT to simulate the deposition of particulate matter in the ventilation pipe. The results showed that the deposition of different diameter particles in the filter tube was different. The movement of the larger particle size (particle diameter >10 μm) was mainly affected by the influence of gravity and inertia, while the fine particles are easily deposited on the inner wall side of the elbow mainly by the turbulent diffusion. Therefore, the angle of the elbow should be adjusted to direct the airflow so that most of the particulate matter could deposit on the filter element, reducing the particulate matter from the exhaust port and the damage to the human body in the room, which will improve the dedusting effect of the purifier.

Usate of Filter Tube to Reduce Pb, Turbidity And Increase pH of Rain Water Flowing Through Zinc Rooftop House

Pb contained in rain water comes from zinc rooftop, beside that, it comes from the pollutant dissolved and comes into rain water reservoir and is used for community drinking water source. This research objective is to evaluate Pb, pH and turbidity of rain water before and after process and to analyze efectivity of shell sand filtration and activated carbon absorbtion in the filter tube to decrease Pb and turbidity and increase pH of rain water. This research is an experiment with pre and post test design with control and observational with cross sectional design. It is conducted in Pontianak and Kubu Raya West Kalimantan in 2016 with two target regions which represent urban and rural ones. The result indicated that average lead (Pb) contained in rain water and turbidity process is high with 131.7 g/l and 20 NTU and pH is low with 5.2. After process, Pb become 0.71 g/l and turbidity become 5.66 NTU while pH increases to 6.9. The effectivity of filter tube to reduce lead (Pb) contained in rain water is 99.4% and to reduce turbidity is 72%.