Science & Technology Development Journal - Science of The Earth & Environment

Study on using modified laterite in the heterogeneous Fenton process for removing dye compound

Huy-Dinh Vu — 2019-11-26

In this work, was modified by iron (III) sulfate (Lat-Fe), and it was used in heterogeneous Fenton for the removal of Reactive Yellow 160 dye (RY 160). Properties of chemical composition, surface morphology and specific surface area of modified were characterized by Energy X-ray spectroscopy (EDX), scanning electron microscopes (SEM) and BET method and that was assessed effectively to apply in the heterogeneous Fenton process. Experimental investigations about conditions such as pH, H₂O₂ concentration, and modified materials were conducted to look for the suitable conditions for removing dye compound by Fenton process. Studied results showed that modified by procedure without iron Fe³⁺ had not catalyzed activation in Fenton process. However, using modified by iron (III) sulfate (Lat-Fe) get good results in the heterogeneous Fenton process for removing Reactive Yellow 160 dye. Removing Reactive Yellow 160 dye (RY 160) with initial concentration of 50ppm with investigated optimal conditions of Lat-Fe: 1,25g/L, H₂O₂ 2,45 , pH 7 at 30^oC get 70% of removal efficiency in 120 minutes.

Development of agro-industrial eco-model (aicem) for production of raw coconut jelly sector in Mekong Delta

Tran Thi Hieu — 2019-12-29

The argo-industrial model producing of closed ecosystem in Mekong Delta is a development in the world. In this paper, the construction method outlined criteria identifys for the agro-industrial production model toward dual-closed ecological direction for coconut jelly processing facility. Set up criteria determines the impacts of production technology, the efficiency of using energy and natural resources, sustainable livelihoods, and the replicability of the model that will affect on the sustainability of the model. The research methodology was based on the results of surveys, investigation, and assessment of current model, and identifying a scientific basis for the set up criteria. Based on that, set up criteria was propose and application for a coconut jelly processing facility for Nguyen Thanh Trung household in Nhon Thanh commnune, Ben Tre city, Ben Tre province and recommend the solution for completed model based on eco-technique and closed matter & energy line. The results of the model meet all the requirements of the set up criteria. The quality of water supply meets the standards for coconut jelly processing. Treated wastewater by aquatic plants system meets the standard for wastewater discharges into the water resource. Water comsumption was saved and reduced the greenhouse gas emissions from burning wood for coconut jelly processing. The production costs were saved, resulting increasing income for household. This is pilot the perfected model to expand to other facilities.

Propose a model integrated farming production towards zero emissions for livestock households: typical application for cattle breeding households in Seven Mountain areas

Le Trong Nhan — 2019-12-31

The study has proposed an integrated zero-emission farming model based on livestock production. The model applies ecological solutions, revolving solutions, and closures of energy flows along with utilizing the local environmental conditions available to help maintain livelihoods for the people. Typical models for Mr. Nguyen Van Hai households in Trung An hamlet, Le Tri commune, Tri Ton district, An Giang province. The results show that 3.18 m3/day of livestock and domestic waste water is treated and reused for agriculture, 39,065.31 tons of CO2tđ/year is collected in the form of biogas for cooking, models help to maintain existing livelihoods, creating a number of new livelihoods to increase income of VND 64,400,000/year, ensuring environmental protection requirements, reducing existing livelihood dependence on external actors such as price, food, human resources, etc. This can be considered as the best model for cow farmers; can overcome the disadvantages of previous local livelihood models; Both in terms of long-term applicability, as well as the development of a large number of households, there is an increase in the ability to connect among households in order to create mutual support in the case of a residential area with the same main livelihood as livestock cow.

Testing of the Multi-Physics Ensemble Kalman filter to Simulate the Track and Intensity of the Typhoon HaiYan (2013)

Pham Thi Minh — 2020-01-06

This paper presents some experimental results of the multi-physics ensemble Kalman filter method which assimilating the satellite wind data in WRF model to simulate the track and intensity of the typhoon HaiYan (2013). The study conducted two experiments.: (1) Ensemble forecast with multi-physics ensemble Kalman filter assimilates the satellite wind data (CIMSS); (2) multi-physics Ensemble forecast (MPH). The results of atmospheric circulation analysis in the simulation started at 12 UTC (international time) until November 7, 2013, showing that the trend and intensity of the general circulation in the CIMSS test are similar to the real development. So the results of the storm trajectory forecast of CIMSS test at the 48-hour forecast limit onwards are better than the MPH test. Moreover, experimental results based on the results of the 6 simulations for simulation error, the track error in the CIMSS test decreased 14% and 14.3% respectively in the 48-hour forecast period and 72 hours compared with the MPH test, and decreased 14% and 23.9% respectively compared to the global GFS forecast. For storm intensity (Pmin and Vmax), the CIMSS test also resulted in significantly improved errors in the 72-hour forecast period compared to MPH testing. These results confirmed that the assimilation of the satellite wind data into the input field of the model has a positive effect on Haiyan storm intensity and trajectory prediction skills. We may use this research to applying the multi-physics ensemble Kalman filter for forecasting storms affecting Vietnam.

Research application coal material is prepared from maccadamia peel and denatured by H2O2 to treat methylene blue

Dao Minh Trung — 2020-01-08

Macadamia shell contains a carbon content (47 - 49%), in addition, the shell contains 46.52% Oxidation, Hidro 6.10%, Nitrogen 0.36% and relatively low ash content of only 0.22%, this indicates the grain Macadamia has the potential to become activated carbon thanks to the above characteristics. This study was conducted to modify activated carbon by oxidizing agents to change the surface structure of activated carbon from hydrophobic to hydrophilic, non-polarizing to polarization, increasing the amount of adsorption simultaneously creating more durable links between dyes and activated carbon. Study of Methylene Blue wastewater treatment with coal from Maccadamia shell modified with H₂O₂ agent at H₂O₂ ratio : coal = 10:1. Research results show that Methylene Blue adsorption capacity reaches 1g /266,26mg Methylene Blue at optimal conditions corresponding to 25% concentration and 48 hours of soaking time. Analysis of infrared spectra showed that coal is modified by H2O2 agent with functional groups –OH, Carboxylic functional group C=O, group C-H in NH₃, C–N group in Amine aliphatic or in Alcohol or Phenol and C–O bonding. Modified coal by H2O2 oxidation agent has Methylene Blue color treatment efficiency of 93.26%, corresponding to the original color of 474.67 Pt - Co at the respective optimal conditions pH = 8.5, dose of 1 g/L and treatment time of 60 minutes. Research results are similar to other research results and are applicable to color wastewater treatment.

Color removal efficiency of rice husk biochar modified with magnetized iron oxides and nano zero valent iron for decolorization of dyeing wastewater

Bao-Son Trinh — 2020-01-09

Rice husk biochar, a rich-carbon material, can be modified with other reactive elements to improve its original properties for organic-contaminant removal efficiency. In this study, rice husk was heated to 600 oC without air in a closed-furnace for producing the rice husk biochar (BC600). BC600 was then magnetized for making an intermediate magnetized rice husk biochar (BC600-mag). Finally, nano zero valent iron (nZVI) was synthesized on BC600-mag for producing magnetized biochar impregnated nZVI (BC600-mag-nZVI). Batch experiments were conducted to investigate color removal efficiency of BC600-mag-nZVI for the reactive dyes yellow (RY145), red (RR195) and blue (RB19) from dyeing solutions with the initial color concentrations of approximately 400 Pt-Co. Results showed that, for RY145 and RR195, the optimum color removal efficiency (ɳopt) achieved the values of 95 and 93% at doses of 0.50 and 1.50 kg BC600-mag-nZVI/m3 dyeing solution, according to the treated color decreased to 21 and 30 Pt-Co, respectively, which are lower than the allowable discharged standard of column A (≤ 50 Pt-Co) of QCVN 40:2011/BTNMT, while for RB19, the ɳopt achieved the values of 63 % at dose of 8.00 kg BC600-mag-nZVI/m3 dyeing solution, according to the treated color decreased to 147 Pt-Co which is lower than the allowable discharged standard of column B (≤ 150 Pt-Co) of QCVN 40:2011/BTNMT. In addition, with increasing dose of the modified biochars, the color removal efficiency increased accordingly, achieving almost 100% for RY145 and RR195 and over 70% for RB19. It is concluded that the magnetic-nZVI rice husk biochars effectively removed the reactive dyes. In the other hand, the impregnation of nZVI particles on the biochar backbone spatially separates the particles, prevents their aggregation and therefore enhances their reactivity This study therefore proposes a new application of rice husk biochar modified with magnetized iron oxides and zero valent iron decolorization of dyeing wastewater.