GS. vs. Đặng Vũ Minh Phó Trưởng Tiểu ban

GS.VS. Đặng Vũ Minh

TS. Vũ Đức Lợi

TS. Đoàn Văn Bình
Ủy viên:

PGS.TS. Tăng Thị Chính

PGS.TS. Nguyễn Thị Huệ

TS. Ngô Tuấn Kiệt

PGS.TS. Trịnh Văn Tuyên

PGS.TS. Vũ Anh Tuấn

PGS.TS. Đinh Thị Mai Thanh

TiO₂ doping nitrogen immobile on silica gel (TiO₂/SiO₂) was synthesized by sol-gel method. TiO₂ particle on SiO₂ has anatase crystalline structure. As the XRD, SEM and HR-TEM images showed, the diameter of TiO₂ practical was around 10nm. The results of absorption spectra indicated that the band gap of anatase TiO₂ with Degussa P25 powder was 3.2 eV, while the band gap of anatase TiO₂:N was 2.5 eV. UV-vis spectrums proved that TiO₂:N/SiO₂ sample can absorb visible light. These results showed the TiO₂: N/SiO₂ perform of decomposing DDT under 6 hours UV lighting was 82%.

Vietnam has the amount of industrial wastes about 6 to 7,5 million tons per year. It causes environmental pollution, adversely affects the life of communities. Cement industry uses about 6,5 to 8,4 million tons of coal per year, can replace 15% of its fuel amount by using many resources of wastes from agriculture and industry. The Ministry of Natural Resource and Environment issued QCVN 41/2011/BTNMT for co-processing of hazardous wastes for cement kilns, which has made a big opportunity in using "valuable waste resources" as alternative fuels and contribute to the environmental protection and sustainable development in Vietnam.

The management of waste activated sludge (WAS) recycling is a concern that affects the development of the future low-carbon society, particularly sludge reduction and biomass utilization. In this study, we investigated the effect of removing extracellular polymeric substances (EPS), which play important roles in the adhesion and flocculation of WAS, on increased sludge disintegration, thereby enhancing sludge reduction and methane production by anaerobic digestion. EPS removal from WAS by ethylenediaminetetraacetic acid (EDTA) significantly enhanced sludge reduction, i.e., 49% compared with 27.1% of the control at the end the digestion process. Methane production was also improved in WAS without EPS by 8881 µmol/g dry-weight of sludge compare to 5724 µmol/g dry-weight of sludge without EPS removal. Microbial activity was determined by denaturing gradient gel electrophoresis and real-time polymerase chain reaction, which showed that the hydrolysis and acetogenesis stages were enhanced by pretreatment with 2% EDTA, with a larger methanogenic community and better methane production. The results of the study might open a new direction in WAS management, treatment and renewable energy recover.

In this article it is presented the procedure of synthesising polyester polyol from Bis-hydroxylpropylbisphenol A. The procedure is followed into two steps. In the first step, waste polycarbonates are hydrolysed in toluene solvent with propylene glycol (PG), catalysed by Na₂CO₃ at 180^oC for 60 mins. In step 2, the product obtained in step 1 has been alkoxylized with urea and ZnO added at 180^oC for 4 hours. Reaction ratio can be reached more than 90%. Physical properties of products have been studied by IR spectroscopy and NMR. It is pointed out the structure in quite agreement to those of bishydroxypropylbisphenol A. Beside of the scientific and economical means; our research has found the highly effective solution in recycling polycarbonates in limitation of environmental pollution.

In this article it is presented the procedure synthesis of polyester polyol from Bis-hydroxylpropylbisphenol A recycled from waste polycarbonates (PC). Synthetical details have been investigated by measuring the changes in acidic index. After 20 hour reacting reaction mixture has shown the acidic index is 2.1 and –OH group ratio of 80. Physical properties of polyol polyester products have been studied by IR spectroscopy and NMR. By permeating chromatography method, it is determined of the average molecular mass of product approaching the value of 6910 amu.

Starch degrading bacteria are most important for industries such as food, textile, paper and wastewater treatment processes. Amylase production from bacteria plays a vital role in treatment and clean the wastewater from noodle production villages in which the starch is the most abundant. This study was aimed to isolating and charactering the best amylase producing strains and as well as optimizing growth condition in wastewater treatment. Forty three bacterial strains isolated from wastewater of noodle production villages and 23 strains of these were found with starch degrading abilities. PD17 strain was the best amylase biosynthesis bacteria. Characterization features of potential PD17 strain that showed a Gram positive, rod-shape, aerobic bacteria was identified as Bacillus subtilis by morphological methods and by API 50 CHB/E kit. The optimum temperature and initial medium pH for amylase synthesis by the PD17 strain were 35⁰C and 7.0 respectively. The starch degrading bacterial density in the sludge which included PD17 strain reached over 10⁹CFU/ml after one week expriment.

⁴Institute of natural products chemistry, Vietnam Academy of Science and Technology

The aim of the present study was to investigate the influence of silver and copper nanoparticles on Cyanobaeria strain Microcystis aeruginosa. The silver (10nM) and copper (20 -50 nm) nanoparticles were synthesized by chemical reduction methods. Characterizations of these nanoparticles were determined by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and UV - VIS methods. Silver and copper nanoparticles show growth inhibition against M. aeruginosa. At concentration of 1 and 5 mg/L of silver and copper nanoparticles, maximum anti-algal activity was observed.

Hydroxyapatite/chitosan nanocomposite (n-HAp/ChS) was synthesized by chemical precipitation method from 0.5 M Ca(NO₃)₂ + 5% chitosan/2% acetic acide solution and 0.3 M (NH₄)₂HPO₄ solution at pH 10-11 by using 28% NH₃ solution. The obtained n-HAp/ChS powder had cylinder shape with crystal size of about 17x30 nm and specific surface area of 42.01 m²/g at 180^oC. The effect of factors including the contact time, the amount of n-HAp/ChS, the solution pH, F^- concentration and temperature on the fluoride adsorption capacity and efficiency was investigated. The defluoridation efficiency obtained 91.357 %, adsorption capacity 2740.72 mg F^-/kg at natural pH, F^- concentration of 15 mg/l, temperature 40^oC and contact time 30 minutes with n-HAp/ChS mass of 0.25g.

In recent years, industrialization and urbanization has been taking place rapidly and municipal solid wastes are also increasing significantly with time. This paper concentrated to evaluate the ability of Effective Microorganism in composting of municipal solid waste and to produce microbial-organic fetilizer. The addition of thermophilic microbial preparation Sagi- Bio makes to short the processing time under 20 days, simultaneously reduces the H₂S and NH₃ in this processing. The microbial-organic fertilizer exceeded the Circular on guidelines No 41/2014 BNNPTNT for microbial - organic fertilizer produced from solid wastes. Using microbial organic fertilizers produced from waste had effective for reclamation and increasing crop yields (11 – 19% for rice, cabbage and tea yields). Additionally, the quality of vegetables using these organic compost produced from municipal solid wastes were satisffied for food safety (not contain pathogenic microorganisms and heavy metals).

Studies on To Lich River indicated that the water is heavily polluted by untreated urban wastewater. Pollutants discharged into the river have negative impacts on aquaculture in downstream area. This study examines the optimal conditions of coagulation process applied for To Lich River’s water by conventional and polymeric coagulants. The highest percent removal efficiency of turbidity and natural organic matter (NOM) obtained at 180 mg/L of ferric salt and 150 mg/L of alum at the pH range 5 -7; 30 mg/L of poly aluminium chloride at pH of natural water. Poly aluminium chloride is superior over conventional ferric chloride and alum coagulants in terms of pH independence, lower dosage and less sediment. With the addition of Fenton/UV oxidation process as combined method, the COD removal and deodorisation was significantly improved. These results suggest that an integrated approach may be exploited for optimized treatment on To Lich River’s water.

Institute of Environmental Technology, Vietnam Academy of Science and Technology has been approaching the Eco-Bio-Block (EBB) prototype from Japan for water treatment.

In this study, the method to manufacture the EBBs, modified based on the materials and microorganisms available in Vietnam for COD removal from wastewater was developed. Besides the ability to adsorb and absorb some pollutants, the modified EBB products contains microorganisms that are capable of actively decomposing organic substances and nutrients in the water.

For the experiment, the wastewater taken from a sewer from the residential area in Nghia Do ward (Cau Giay district, Hanoi), connecting to To Lich river, which has COD concentration ranging from 150 to 350 mg/L. Total weight and volume of the modified EBBs used are approximately equal 1.6% and 3% of those the waste water in the experiment basin.

The assessment of the treatment capacity of the modified EBBs has been performed with pH in the wastewater varied from 4 to 10. The experimental results showed that with the pH range from 7 to 8, the COD removal efficiency of modified EBBs reached nearly 90%.

From these results, it is suggested to conduct further investigation of EBBs in order to find technical solutions for domestic wastewater treatment handling at a low cost. Moreover, this method could be applied to other types of wastewater in Vietnam.

This article presents a novel technology for removing nitrogen compounds such as NH₄⁺, NO₃^-, NO₂^- exists in acid mine drainage (AMD) of the system combining limestone, sawdust and microorganism in laboratory scale. The anammox, nitrification and denitrification reactions are combined in nitrogen compounds' removal processes. Two varied reduction sources - inorganic (sulfide) and organic - are used for the denitrification, which is created in the hydrolyzation of sawdust and reducing sulfate into sulfur in microbiology system. The system was operated in 1 year in 3 different phases with the hydraulic retention time of 1,5 days (phase A), 1,1 days, aeration rate 0,3 L/Lmin (phase B) and 1,1 day, aeration rate 0,6 L/Lmin (phase C). In the system, the average concentration of NH₄⁺-N in the inflow varied from 11,81 to 8,52 mg/L, while in the outflow only remains 4,16, 1,68 and 0,26 mg/L respectively. The average concentration of ion NO₃^--N at the inflow approximate 24,44; 17,84 and 37,48 mg/L respectively, however, in the outflow, it reduced to 9,96 mg/L, 3,98 and 3,66 mg/L respectively. The inflow concentration of ion NO₂^--N is insignificant, although, the ion concentration reaches 1,28; 0,21 and 0,39 mg/L in the outflow.

Actually, pharmaceutical residuesin the environment have known as the agent to constitute a health risk for aquatic ecosystems and human. An occurence of 9 active compounds (diclofenac, ibuprofen, ketoprofen, naproxen, carbamazepin, atenolol, metoprolol, propanolol, sotalol) was investigated in 4 effluents of WWTP in South-West, France. 32 samples were collected from 2011 to 2012. These samples has been extracted by using solid phase extraction (SPE) before analyzing by LCMSMS system. All analyzed compounds were detected at high rate (>90% of samples) in all samples which concentration has been varied from some hundred ng/L to some µg/L. The highest concentration were found for atenolol and sotalol (up to 8µg/L and 10µg/L respectively). In this study, the photo-degradation of pharmaceutical residues under solar light was also examined. Diclofenac, ketoprofen has strongly photo-degraded while ibuprofen, carbamazepin, atenolol, metoprolol seems to be stable againt solar light. The half-life time has measured in both waters (ultrapure - UPW and river - RW) diclofenac (35 and 36min), naproxen (207 and 175min), sotalol (142 min in river water) and propanolol (1124 and 236min). However, the photo-degradtion of naproxen, propanolol and sotalol has been strongly influenced by natural organic matters in water.

Laterite ores, having low cost and very high amount in Vietnam, was studied fluoride-adsorbing ability. There were 3 methods studied for denaturing Laterite and Pyrolusite in this paper to be: temprature, acid HNO₃ and NaOH. The method using acid HNO₃ (1 M, shaking time for 2 hours) was the best for denaturing Laterite (adsorbing efficiency: 64.4 %, adsorbing capacity: 32 mg/g). The denatured Laterite optimally adsorbed fluoride at pH to be 2 and in shaking time to be 150 minutes.

Two wastewater samples were applied to estimte fluoride adsorbed ability of denatured Laterite. The efficiency for adsorbing fluoride ranged from 49.7 % to 51.2 % and adsorbing dose was 25.1 mg/g.

Keywords: Laterite ore, denature, adsorb, fluoride, wastewater.

STUDY OF ABSORPTION AND ION EXCHANGE POSSIBILITIES WITH HEAVY METAL OF BARI HYDROXYAPATITE NANO POWDER

Vo Thi Hanh^1,*, Le Thi Duyen¹, Đo Thi Hai¹,

Nguyen Thi Thom² and Đinh Thi Mai Thanh<sup>2

1</sup> Hanoi University of Mining and Geology, Duc Thang, Bac Tu Liem, Hanoi

²Institute for Tropical Technology, VAST, 18 Hoang Quoc Viet Road, Hanoi

^*Email: vothihanh2512@gmail.com

ABSTRACT

Barium hydroxyapatit nanopowder (abbreviated as BaHAp) was synthesized by chemical precipitation method from water solution included Ba(OH)₂ 2.10^-2M and H₃PO₄ 3.10^-3M at pH always greater than 10. The analytical results of morphologies, phase composition and specific surface area showed that the obtained BaHAp powder had crystalline structure, cylindrical shape with dimensions of about 18x28 nm and specific surface area of 25 m²/g. The effect of factors including the contact time, the mass of BaHAp, the solution pH and temperature on the adsorption and ion exchange with ion heavy metal cations (Cu²⁺, Pb²⁺, Cd²⁺) was investigated. The results, if mass of BaHAp was 1.2g at the temperature 70°C and pH 4.5 for 30 min, the removal efficiency simultaneously of Pb²⁺, Cd²⁺, Cu²⁺ ions could reach respectively 94%, 85% và 91%.

Currently, in many parts of the world as well as in Vietnam, water sources are seriously contaminated by heavy metals, affecting dramatically the environment and people's health. Using chemical and physical methods (precipitation, red-oxidation, ion exchange, coagulation, adsorption, electrochemical method, membrane,...) can be achievable according to the Vietnam standard (QCVN 40: 2011). But these treatment technologies have high processing costs due to the use of chemicals and expensive materials while residual chemicals could cause secondary pollution to the environment. Therefore, finding other methods to remove Cr, Ni in wastewater with cheap cost, short time and high treatment efficiency is necessary. In our study, the experiment was conducted using cheap materials such as sawdust and limestone to determine ability of removing Cr³⁺, Cr⁶⁺, Ni²⁺ from wastewater. With different initial concentrations of Cr, Ni ranging in 50-300 mg/l, the remediation efficiency of these heavy metals has reached more than 99% after 24 hours and the lower heavy metal concentration is, the higher treatment efficiency can be achieved.

Research included steel slag as adsorbent and remove environmental pollutants is a priority direction in the trend "use waste treatment waste”, because steel slag is one of the solid waste harmful to the environment the danger level. During study of steel slag adsorption and removal As, we make new experiments aimed at reforming existing of steel slag to modify steel slag efficient adsorption and arsenic removal in water. Results compared adsorption features and efficient arsenic removal between modified steel slag and unmodified steel slag shows: modified by acid then its dramatically reduced; modified by alkaline then its increased; modified by salt then its mitigated; modified by high temperature activation then its clearly increased; modified by organic loading capacity its also increased clearly. Thus, in the process of experiment modification steel slag properties not always bring good results, but we will continue working to find the best methods to enhance the adsorption features and arsenic removal by steel slag, as well as finding the most effective measures for the prevention and treatment of environmental pollution.

Studies of heavy metal contaminated soil are sparse in Vietnam, and have focused on physico-chemical methods. Nowaday, more and more attention has been paid to the research on phytoremediation. Heavy metal uptake by suitable plant species depends on many different environmental factors. Nutrients are one of the most important factors because the plant growth needs them. In this study, the pot experiments were conducted in 120 days to understand the effect of different nutrient types on Arsenic (As), Cadmium (Cd), Lead (Pb) removal capacity of Vetiveria zizanioides L. The results showed that, heavy metal concentration in the root is higher than that in the front of the grass. The growth and As, Cd and Pb removal efficiency of Vetiver grass from the soil amended with both inorganic and organic fertilizer is highest (6 g NPK and 2.5 g Song Gianh per 6 kg soil). The heavy metal removal ability from the soil of the grass in the control (without fertilizer application) is lowest, concentration of As, Pb and Cd in the shoot of control is 32.4±3.6, 104.5±15.1 and 0.06±0.01mg/kg, respectively. Translocation factor (TF) in the experiments showed a poor efficiency for As and Pb (both less than 0.2 in all the treatments), but a quite high TF of Cd (0.5-0.9).

The study presents the results of the model on research and development of long-term energy system development of Vietnam, with consideration on energy security. The model is divides Vietnam energy system into eight geographical regions. The problem of optimizing the energy system according to geographical regions is constructed and solved by the linear planning methodology. Based on the forecast database of three scenarios of socioeconomic development and data from strategies and master plan of sectorial development including coal, oil and gas, power, renewable energy, and nuclear power up to 2030, as well as the sectorial risks, the study combines and calculates 45 scenarios with the Corrective – Module 1 software. The calculating result at baseline energy demand, in which all types of energy – fuel complex are exploited at baseline productivity amount, up to 2030: Total primary energy consumption is 186.5 mil.TOE; Total imported energy is 110.43 mil.TOE; Dependency on imported energy is 51.29% (proportion of imported energy out of total primary energy demand); Requirement on power generation is 586.94 bil. kWh; Total cost for energy system is 166.49 bil. USD (USD 2010).

Most high-voltage underground cables are composed of many layers of insulation and protection; therefore; the study of transients in high-voltage underground cables is complicated, which requires the accurate description of the transition’s impact on the underground cable. This paper presents the method of mathematical modeling and simulation of high voltage underground cable in the transition state by describing the precise components including conductor, insulator, semiconductor layer and armor in analysis of cable transition. The study results are calculated for a modeling grid with the EMTP software.

In building energy management, the electrical storage is important to ensure power supply continuity and reduce cost of electrical consumption. Therefore, an electrochemical battery model is highly recommended for our main objectives, which can contribute to simulate the impact of electrical storage in the building. In our framework, we have developed a complete solution for the electrical optimal management, including prediction, optimization, and real-time management of an electrical storage system with photovoltaic generation. We firstly present the models required to predict consumption patterns, production and storage. Then, under our experimental platform, we detail the predictive control algorithm, monitoring solutions and equipment control, as well as the results obtained. In near future, this research will be applied for the “Micro Smart Grid Development and Application for Building Energy Management” project (USTH, HIT, G2Elab and VAST).

This paper presents an online method of operating the electricity distribution grids with distributed generations. This method is based on the reconfiguration problem online distribution grid with distributed generations, considering the impact of the change and the load capacity of distributed generations in sub-graph load typical day. In this paper constructed a cost function C_L deviation based on the analysis of costs when operating the power grid configuration changes to the cost of power loss. Based on C_L function will make the decision to operate in the process of selecting grid distribution profile taking into account the distributed generations.

The article presents briefly some results from a research conducted by the Institute of Energy Science on the theme “Assessment of the current energy consumption of steel, cement and paper production industries in Viet Nam; Recommendations for saving and efficient use of energy”. These are large production industries, consuming the most energy. In 2011, they consumed energy equivalent to 305,630 TJ or 7,301 ktoe; green-house gas emission equivalent to 8,762 ktCO2. The total potential of saving energy of these industries was about 94,686 TJ or 2,262 ktoe. In which, steel industry accounts for 17.7%, cement industry accounts for 72.4% and paper industry accounts for 9.9%. Results from the research were used for the White Paper on Energy Efficiency & Climate Change Mitigation (EE & CC) – VBCSD/ VCCI Recommendations to the Government of Vietnam in 2014.

Vietnam’s cultivation sector has been developing, with variety of vegetables and fruits, which can be harvested throughout the year to meet domestic and exporting demand. The amount of waste from the production and processing of this sector is large and increasing. This is also an abundant source of raw materials, which can be used for energy production. This paper presents the application of microbial strain isolated in Vietnam to metabolize the slightly soluble polymeric compounds into soluble low-molecular compounds as feedstock for biogas plants. After 21 days of incubation, the levels of cellulase, pentoza and lignin significantly reduce; the substances dissolving in cold water increase by 43.32 %. Using soluble low-molecular compounds for biogas tank results the gas composition of 57.8 % of CH₄, 36.3% of CO₂, which is suitable for burning for heating and electricity generation.

The paper presents the result of pilot producing and burning the water - FO emulsion by a Belarusian originated technology at the Institute of Energy Science under the national pilot production project of "Pilot manufacture of water - FO emulsion production equipment for energy efficient when start-up and combined burning in coal fired power plant", Code: KC.05.DA.04/11-15. The equipment system of producing water - FO emulsion was pilot manufactured, and the water - FO emulsion was tested burning. The results showed that the produced emulsion has the water proportions of 10%, 17.5% and 22.5%, which met the standard of the Belarusian technology. When being tested burning in the FO fired boiler of Dong Giao Food Export Company, the emulsion is stably burned and showed its potential of being applied in Vietnam practical conditions.

Synthetic curve of equipment wave energy converted into electricity with stable power supply and high capacity requirements by wave chamber will reflect the capacity of the model to the varie workspace (wave regime) according to the wave conditions (wave period, wave length, wave height). The construction of the synthetic curve is not the basis of the energy equation, but also need experimental studies. The article refers to the theoretical foundations and empirical characteristics in constructing synthesis curve of equipment wave energy converted into electricity with stable power supply and high capacity requirements by wave chamber matching wave regime of coastal areas in Thanh Hoa province. The article is the result of the research: "Research design, test pattern generator stable, high performance wave energy" under the direction of priorities science and technology: Environment and Energy, VAST codes 7:04/14-15.

Gasification of biomass fabricating syngas fuels has contributed to expand applicability of solid biomass fuel. However the byproduct tar of the gasification largely limited the effectiveness. This paper presents a possibility using Fe – catalysts during gasification in order to reduce the tar and increase the gas quality.

The catalysts have been fabricated by two techniques: pyrolysis and milling. Properties, structures, particle dimension have been examined. The suitable condition has been chosen for effective fabrication. The studied catalysts will be applied together with ourselves constructed gasifier which is integrated a generator.

Keywords:

BIOTECHNOLOGY POTENTIAL OF PRODUCTION HYDROGAS FROM STRAW USE OF NEW ENERGY SOURCES

Nguyen Hoang Nam, Cong Tien Dung

Hanoi University of Mining and Geology, Duc Thang, Bac Tu Liem, Hanoi, Vietnam

* Email:

ABSTRACT

This paper presents results of the initial researching process producing hydrogen from straw using biotechnology. In the medium of enriched microbial biological sludge thermal shocked, straw is added as carbon source for microorganisms and as materials to create hydrogen, obtained microorganisms is thermophilic, anaerobic and the best hydrogen producer. In the condition of temperatures around 55-60°C, the enriched biological sludge were diluted with the nutrient solution at the rate of 1:4, consist of 130 g/l straw, hydrogen levels obtained after CO₂ and H₂S removed reach 17.82% by weight. The study results showed great potential of biotechnology in the production of hydrogen gas from agricultural waste.