EFFICIENCY OF INTEGRATED ULTRASONIC AND ANAEROBIC ,

efficiency of anaerobic digestion can be greatly enhanced by using physical and/or chemical pretreatment , effect of ultrasound on anaerobic digestion of oil refinery sludge subjected to different variabl 2 Methods 21 , Iran After passing the physical units and chemical processes (coagulation and flocculation), the refinery ....

THERMODYNAMIC PROCESS MODELING AND SIMULATION ,

new design in order to increase the water and thermal energy recovery in the digestion process unit The simulation results showed that in the new design, the pre-heater sections can gain 571GJ/h additional heat, and the fresh slurry temperature increases by 11°C...

DIGESTION ALTERNATIVES OF THE GREEK DIASPORIC BAUXITE ,

The tests confirmed that beside the well-known advantages of this bauxite, as the high alumina and very low silica, organics, moisture and bound water content - and in consequence the low specific bauxite consumption per tonne of alumina, - high extraction yield and adequate cycle efficiency (low caustic molar ratio in blow-off slurry) can also ....

Application and Benefits of Advanced Control to Alumina ,

APPLICATION AND BENEFITS OF ADVANCED CONTROL TO ALUMINA REFINING Robert K Jonas Honeywell Int, 2500 W Union Hills Dr, Phoenix, AZ, 85027, USA , several digestion units have be controlled from a single MPC application, however for larger , Application and Benefits of Advanced Control to Alumina Refining...

Daniel Cavichioli - Process Engineering Superintendent ,

Responsible for CBA's Alumina Refinery production, costs and product quality KPI's, as well as the process optimization and plant efficiency improvement projects Led the operating model system optimization work, ensuring the plant performance goals were met at the operational level...

Alumina Refining Automation Solutions - Honeywell

Alumina Refining Automation Solutions , yield improvement of over 1% through the application of advanced control for digestion Other operations have , alumina refinery was able to start up six weeks ahead of schedule Another example is the Worsley Alumina upgrade project, which earned an...

Thermodynamic Process Simulation of the Digestion Unit in ,

The Jajarm Alumina Refinery digestion line was simulated using the Elec-NRTL property model and Aspen simulating tool DISCUSSION AND CONCLUSIONS The data shown in Table 5 was computed by the simulation program for the 130 kg/m3 volume flow rate condition...

Bayers process reactions - SlideShare

Bayers process reactions , the auto- precipitation losses are higher resulting in net reduction in extraction efficiency 3 Digestion Process Presently three digestion technologies are being employed through out the world , which can be precipitated per unit volume of liquor So the alumina charge at digestion stage is to be maximized to ....

5 WAGERUP REFINERY UNIT 3 PROPOSAL DESCRIPTION 51 ,

Wagerup Refinery Unit Three May 2005 Alcoa World Alumina Australia Page 70 Ref , achieved through upgrading existing equipment to increase capacity and efficiency As alumina production increases so too will the requirement for raw materials, water and energy , sealed units 5132 Digestion The two existing digestion units will be ....

PERFORMANCE IMPROVEMENT OF ALUMINA DIGESTORS

alumina extraction efficiency NOMENCLATURE B baffle width [m] , The Alumina refinery at Hindalco, Renukoot, India is , Digestion is the basic operation of this technology The main raw material for digestion operation of alumina plant is bauxite slurry after desilication The main chemical reaction in digestion ,...

Worsley Alumina Pty - Murdoch Research Repository

The Worsley Alumina refinery uses a modified Bayer Process to extract alumina from , as goethite and hematite The manufacture of aluminium metal begins with the Bayer Process The Bayer Process is an extraction process that relies on a specific property of bauxite which enables separation from , alumina At this stage of the digestion ....

PERFORMANCE IMPROVEMENT OF ALUMINA DIGESTORS

The digestion efficiency is significantly affected by the mixing process occurring at all scal , substantial improvement of the alumina extraction efficiency , The Alumina refinery at ....

Assessment of flow pattern and mixing phenomena in ,

Joint President and Unit Head Hindalco Industries Limited, Muri, India , affects the extraction efficiency of bauxite digestion Short circuiting (channelling), excess back mixing of slurry, and formation of dead zones are the , chemistry of the alumina extraction ,...

Alumina Tube Digestion - Hatch Ltd

During operational upsets, high transient pressures through a tube digestion unit can potentially expose plant, equipment, and personnel to operational safety risks Solutions The use of innovative high-capacity, single-stream tube digestion technology reduces refinery complexity and improves energy efficiency...

CA2345519C - Feed processing for improved alumina process ,

The treatment process includes: (a) heating the alumina process feedstock to a temperature of 400 °C to 650 °C by direct contact with combustion gas, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process The treatment process also includes controlling the contact time of the alumina ....

The recovery of valuable metals and recycling of alumina ,

of alumina from a waste spent hydroprocessing catalyst: extraction with Na salts M Marafi, M S Rana & H Al-Sheeha Kuwait Institute for Scientific Research, Kuwait Abstract Considering the refinery importance, a spent catalyst recovery study was carried , extraction efficiency was achieved at a catalyst particle size of less than 75 μm ....

Alumina Limited

AWAC improved its bauxite residue storage efficiency (measured by square metres of land required per thousand tonnes of alumina produced) in 2017 by approximately 4 per cent compared to 2015 after achieving the 2020 goal of a 15% reduction in bauxite residue land requirements per unit of alumina 7 years ahead of schedule...

Utilization of waste spent hydroprocessing catalyst ,

Utilization of waste spent hydroprocessing catalyst: development of a process for full recovery of deposited metals and alumina support , energy efficiency and to mitigate environmental impacts Usually, a catalyst , (KNPC) ARDS processing unit The refinery spent catalyst metals (Ni, Mo and V) are recovered as high-quality metal salts at...

ALUMINPRO Consultants Page

Expertise spans bauxite resources, digestion, clarification, filtration, and precipitation areas of alumina refining Major Accomplishments: Assisted with the startup of Gramercy Double Digest process and new precipitation unit at Kaiser's Gramercy refinery...

aluminum processing | History, Mining, Refining, & Facts ,

Aluminum processing, preparation of the ore for use in various products Aluminum , or aluminium (Al), is a silvery white metal with a melting point of 660 °C (1,220 °F) and a density of 27 grams per cubic cm...

aluminum processing | History, Mining, Refining, & Facts ,

Extraction and refining The production of aluminum from bauxite is a two-step process : refining bauxite to obtain alumina and smelting alumina to produce aluminum Bauxite contains a number of impurities, including iron oxide, silica, and titania...

FUZZY TECHNOLOGY APPLICATION IN A BAUXITE ,

FUZZY TECHNOLOGY APPLICATION IN A BAUXITE DIGESTION UNIT Thiago Teixeira Franco 1, , Bauxite slurry and heated caustic liquor are fed into digestion reactors for alumina extraction The main parameter of the reactor output, the A/C (alumina/caustic) ratio is adjusted manually , alumina refinery, smelter, casthouse and downstream process at ....

40 Expanded Operation - NTEPA

refinery design will involve process efficiency improvements in the digestion plant that will reduce the amount of bauxite consumed per tonne of alumina produced by 10%, together with a 23% reduction in the amount of residue...

Alumina Technology (CETI Enterprises)

There is a growing trend in adoption of Tube digestion technology in a few Alumina refineries in planning and execution stages in the World An Alumina refinery of 18 Mtpa production capacity has been newly constructed and commissioned a few years back in Saudi Arabia adopting tube digestion ,...

The Aluminum Smelting Process and Innovative Alternative ,

May 08, 2014· In alumina refineries, bauxite is processed into pure alumina The Bayer process extracts alumina by caustic digestion of crushed bauxite at high temperature and high pressure in an autoclave, followed by clarification, precipitation, washing, and finally calcination to produce pure anhydrous alumina...

4 EXISTING WAGERUP REFINERY 41 ALUMINA REFINING ,

Wagerup Refinery Unit Three May 2005 Alcoa World Alumina Australia Page 53 Ref , which improves alumina extraction efficiency A solution of hot concentrated sodium hydroxide (NaOH, ie caustic soda) liquor, taken from the recycled , The slurry leaves the digestion units containing the alumina in solution (often referred to as green liquor ....

Hydrodesulfurization - Wikipedia

In an industrial hydrodesulfurization unit, such as in a refinery, the hydrodesulfurization reaction takes place in a fixed-bed reactor at elevated temperatures ranging from 300 to 400 °C and elevated pressures ranging from 30 to 130 atmospheres of absolute pressure, , A typical support for HDS catalyst is γ-alumina...

Geochemical speciation of mercury in bauxite - ScienceDirect

1 Introduction The refining of alumina is performed using the Bayer process, which involves the alkaline digestion of bauxite ore in order to dissolve amphoteric aluminium hydroxides that leave a predominantly iron oxide residue...

Refinery Production (t) Year ZM bauxite (%) Year

Conclusion The closed grinding circuit is an adequate solution to improve digestion efficiency in the refinery, with direct effect on increasing alumina extraction and also enabling a reduction of...

FUZZY TECHNOLOGY APPLICATION IN A BAUXITE ,

FUZZY TECHNOLOGY APPLICATION IN A BAUXITE DIGESTION UNIT Thiago Teixeira Franco1, , Bauxite slurry and heated caustic liquor are fed into digestion reactors for alumina extraction The main parameter of the reactor output, the A/C (alumina/caustic) ratio is adjusted manually , digestion unit of CBA, through software Leaf, aiming to reduce...