Tuesday, May 5, 2020

System Design Calculations for Setting up Refractory Grade Alumina Refinery

Hi Friends,

So far, we have covered the operation, technological options, broad design basis, process engineering and process calculations for metallurgical grade Alumina refineries with glimpse of specifications and production processes for non-metallurgical grades of bauxites, hydrates and calcined aluminas. The non-metallurgical grades of hydrate and alumina are also known as specialty grades of products as they have special characteristics particularly with respect to their quality specifications and wide range of industrial applications. Specialty products are value added products mostly manufactured using chemical grade hydrate as the feed stock under strictly controlled process conditions with or without addition of suitable mineralizer. 

Refractory grade alumina (RGA) has high degree of calcination and lower impurities.   In RGA,  Na2content is controlled at lower level as Na2causes formation of voids in refractory at high temperature due to melting and creates cracks which is not desirable.

In present post, we will discuss about the product specifications, production process route and system design including list of major equipment for a typical RGA plant of 3000 tpa production capacity in subsequent paragraphs-

Specifications of Refractory grade alumina:
Al2O3 : 99.0% min.
SiO2 : 0.020% max.
Fe2O3: 0.020% min.
Na2O (total) : 0.35% max.
Na2O (soluble): 0.15% max.
LOI (at 1100C) : 0.30 % max.
α Al2O3 : 90% min.

Typical physical properties of Refractory grade alumina:-
Appearance: White crystalline,
Melting point: 2040oC,
Specific surface area: 0.50 to 1.0g/m2,
Refractive index: 1.76
Hardness: 9 on Moh scale.

Typical sieve analysis:-
+ 100 Mesh: 5 to 20%,
+ 200 Mesh: 40 to 90%,
-325 Mesh: 5 to 10%.

Production Process Route:-
Chemical grade hydrate, the intermediate product of Metallurgical grade Alumina plant, is used as the feed stock for production of Refractory grade calcined alumina. As such, the calcination system with associated material handling and alumina cooling system are the basic facilities of RGA plant but it is preferred to install hydrate washing and filtration equipment at the 1st operating stage of the plant to ensure desired control on leachable Na2O content in the feed hydrate to Kiln. The washed and filtered hydrate is calcined in Rotary kiln at about 1400oC and passed through Air cooler and water cooler for recovery of thermal energy so as to minimise specific HFO consumption for alumina production.

Operating parameters for Rotary vacuum filters:-
Solids in feed hydrate slurry: 45% (w/w),
Cake thickness: 40 mm max.,
Heel thickness: 5 mm,
Vacuum requirement: 700 mm Hg min.
Moisture in filtered cake: 10% max.,
Hot water requirement: 1 m3 per tonne of hydrate,
Specific filtration rate: 1.5 t/m2.hr.

Specifications of Fuel oil:-
Type of fuel oil: Heavy furnace oil (HFO),
Calorific value of oil: 9600 k.cals./kg,
Specific heat of oil: 0.56 k.cal./kg,
Flash point of oil: 250oC.

Typical analysis of Fuel oil:-
C = 87%,          H=10.5%,          S =1.0%,
O=0.10%,         N=0.20%           Moisture=1.2%.

Sizing of Required Horizontal Rotary Vacuum Filter:-
It is assumed that 0.5% of alumina will be lost with flue gas through stack.
Alumina production rate = 1.0 tph
                                                         1.0 *156
Thus dry hydrate to Rotary kiln = ------------- = 1.54 tph.
No. of washing stages on filter =2
Number of filtration stage = 1,
Total no. of washing & filtration stages =3.
Specific filtration rate = 1.5 t Hydrate/m2.hr.
Total filtration area required = 3*1.5/1.54 = 3.1 m2.
Nearest available filter = 4.2 sq.m.

Sizing of Required Rotary Kiln:-
Let effective inner diameter of Kiln = 1.80 m,
Thickness of refractory bricks = 150 mm.
Thus inner shell diameter of Kiln=1.80 m + 2*0.15 m =2.10 m.
Throughput rate of Kiln, tonnes per day = ------------
L = Length of Kiln in meters,
D = Diameter of Kiln in meters and
K = Constant.
For alumina, K =1.10.
Thus 1.0*24 = 1.10*L*(2.1)2
Hence, Length of Kiln, L =14.85 meters.

Rotational Speed of Kiln:-                     
For production of specialty grade alumina,
Kiln rotates at N*D = 2.40,
N=Rotational speed of Kiln in rpm and
D = Diameter of Kiln.
Thus N*2.10 = 2.40
Hence Rotational speed Rotary Kiln = 1.14 RPM.

Trust, the system design calculations for RGA have been described systematically. The material balance and thermal energy balance for RGA plant shall be covered in forthcoming posts.
Please put your views / remarks / suggestions / comments, if any.

Thanks and regards.

Rajendra Kunwar

Sunday, May 3, 2020

Preferred Classification Equipment for Ground Bauxite Slurry

Hi Friends,

In earlier posts, we have discussed about various techniques for grinding of bauxite. The basic objective of grinding of bauxite is to increase the surface area of material substantially so as to improve its reactivity with caustic soda to a desired level during digestion process. As such wet grinding of bauxite has  been found to be energy efficient and environment friendly as well. Ball mill or Rod mill or SAG or combination of any two is generally used in Alumina refineries for the purpose. The particle size of ground bauxite is decided based on the laboratory test work ranging from 149 microns to 1000 microns, however, minus 10 mesh size (100%) has been found to be optimum size in most of the operative Alumina refineries in the World.

In present post, we will discuss the preferred equipment for classification of bauxite slurry in Alumina refinery. Though, open circuit wet grinding may require less capital investment as well as lower energy consumption but it is difficult to ensure desired product fineness. Thus, to ensure the consistency in desired product fineness, closed circuit grinding is adopted in most of the Alumina refineries. For bauxite slurry classification, any one of the following type of equipment are installed in Alumina refineries-
  • DSM Screens, 
  • Banana Screens,
  • Hydro-cyclones.
With regard to capital investment for installation, all three types of slurry classification systems are comparable. But observing the availability for continuous operation, hydro-cyclones are always rated at number one position. The reason being it does not require any descaling and thus downtime is minimal where as periodic descaling of DSM as well Banana screens are mandatory for removal of accumulated scales to ensure desired classification efficiency. Hence considering the availability, reliability and process efficiency, hydro-cyclone is always the preferred classification for Bauxite grinding circuit.

I personally like trouble-free operation of hydro-cyclones over others and love to operate it efficiently. This is purely my personal experience. In case, you differ to my views, please come forward in freely exchanging your own operating experience. We will welcome your views.


Rajendra Kunwar

Saturday, May 2, 2020

Basic Approach for Testing & Commissioning of Alumina Refinery

Hi Friends,

We are well aware that Alumina refinery is a continuous hydro-metallurgical process involving complicated unit operations and unit processes. Testing & commissioning is the 5th stage in execution of new Alumina refinery which comes after Basic engineering, Detail engineering, Procurement and Erection ensuring mechanical completion. Safe and smooth start up of Alumina refinery with due care of human safety, equipment, process input materials and environment are the basic objectives of successful testing and commissioning of Alumina refinery. Thus, successful commissioning of Alumina refinery has five basic objectives as listed below-
·         No loss time accident,
·         No equipment damage,
·         No risk to environment,
·         No wastage of input materials and
·         Stabilization of plant within shortest period.

Sequence of testing and commissioning of Alumina refinery include following major steps-

Field Checking and Punch Listing: 
Field checking of construction completion status of all equipment, instruments, electrical and associated facilities of Alumina refinery, Co-generation plant, Water supply system, Power distribution system, Compressed air system, Cooling tower etc is carried out before testing and commissioning of technological plant and equipment. Based on field checking, a list of required additions / deletions / modifications and design changes are recorded with specific identification number for rectification on planned manner as per priority decided by a team of senior technical professionals of the plant.

System Configuration Checking:
This step is the visual inspection of technological and services equipment as per PFDs, P&IDs, ISOs, specifications and design drawings to ensure their readiness for cold water trials. System configuration checking includes the verification of following-
·         Proper installation of equipment,
·         Fixing of valves and pipelines,
·         Alignment and lubrication of rotating equipment,
·         Direction of rotation of motors,
·         Sealing arrangement of pumps,
·         Proper connections of electrical power supply system.

Checking of Instrumentation and Control System: 
This activity is carried out to ensure the readiness of Instrumentation and control system with respect to following critical aspects-
·         Installation of all instruments and controls as per P&IDs,
·         Setting of alarms and tripping system,
·         Equipment interlocking system,
·         Micro processor signals,
·         Functioning of local and remote sensing equipment,
·       Correct relay of data / information from field instruments to local as well as Central control rooms,

Checking Cleanliness of Process Vessels and Pipelines: 
This task is carried out by flushing out the process vessels and pipelines to ensure removal of obstruction and blockages in the process circuit just before cold water test run.

Checking of Auxiliary System: 
Performance of auxiliary system like Air conditioners, exhaust fans and connected ducts are checked to ensure desired working environment for instruments, controls, equipment and operating personnel.

Training of Plant Operating Supervisors and Operators: 
Objective of training of supervisory staffs and plant operators is to guide them to commission the Alumina refinery safely. It involves following steps-
  • Formation of team comprising of Managers of various disciplines / departments headed by an Expert.
  • Train the Supervisors aiming to ‘Train the Trainer’ who will train the operators,
  •  Review the start up and commissioning procedures,
  • Educating the team with operating and process control parameters including benefits and consequences,
  • Provide technical leadership to facilitate safe, reliable and steady operation of Alumina refinery.
Process and Operating Manual for Systematic Start up: 
This document includes the estimated requirement of input materials and stepwise process sequence for meeting the following basic requirements-
·         Planning for required quantity of input materials,
·         Fixing the responsibilities of individuals in commissioning team,
·         Normal plant start up procedure,
·         Normal shut down procedure,
·         Emergency plant shut down procedure,
·         Procedure for increasing the plant volume steadily,
·         Method for increasing temperature profile of process stream,
·         Guidelines for ensuring adequate supply of condensate to cogeneration plant,
·         Sequence for raising concentration profile of process streams,
·        Planning for aluminate liquor generation and seed charge,
·         Recycling of seed to regular precipitation circuit,
·         Production of hydrate and product alumina.
·         Stabilization of operation of Alumina refinery.

Start up and commissioning of Alumina Refinery:
Bauxite charge to process is considered as the zero date for start up and commissioning of Alumina refinery which is done after caustic concentration build up in selected process vessels to start with for generation of spent liquor and aluminate liquor subsequently. Seed charge enhances the precipitation efficiency thereby generation of seed and product hydrate. Steady control on process and operating parameters stabilizes the plant resulting in target production rate. Calciner is generally commissioned after creating adequate stock of hydrate in the storage shed.

Performance Tests for Plant and Equipment: 
Test runs are conducted with standard agreed procedure for individual plant, equipment and facilities in order to assess the guaranteed performance. However, performance tests for entire Alumina refinery are carried out after stabilization of plant operation to check the assigned production rate and efficiency parameters as agreed by technology supplier, equipment supplier and engineering consultant. 

The above stated guidelines are essentially followed for systematic testing, start up and commissioning of newly constructed Alumina refinery.

Please put your views / suggestions / remarks / comments, if any.

Rajendra Kunwar
Principal Consultant-Engineering
CETI Enterprises,

Saturday, April 11, 2020


Hi Friends,

Looking at the astonished and unimaginable interests on readers on our Alumina Technology Blog forced us to analyse the reasons of such high density of readers traffic.

Members of our team did the thorough analysis to find out the most applicable reasons in consultation with our learned followers across the globe. Basic observations were systematically analysed with statistical tools. The key results and conclusions are listed below:
  1. Unique technical platform with authentic data and information,
  2. Terminology nicely elaborated for easy understanding,
  3. Detailed process and engineering calculations with systematic approach,
  4. Process and control parameters elaborated with clarity,
  5. Equipment design calculations presented with suitable examples,
  6. Methodology described for project costing and production costing,
  7. A to Z from bauxite mining to Alumina production in detail with glimpse of aluminium production technology,
  8. Detailed specifications for variety of bauxite, alumina and alumina chemicals,
  9. Good coverage on production process of each product with focus on market perspective, demand and project profitability,
  10. Benchmark figures on efficiency parameters such as raw material consumption figures and energy consumption aspects,
  11. Process of developing basic engineering documents for all unit operation and processes including design of Residue storage pond,
  12. Simplicity in presentation highlighting important steps.
These are a few major conclusions / observations. Hope, you have also similar opinions. In case, you have some additional comments / remarks, please feel free to place your comments for further improvements in publication of technical posts in future.

Best regards.

Rajendra Kunwar
Key Member of Alumina Technology Team

Tuesday, April 7, 2020


Hi Friends,

We all are always willing to achieve high chemical productivity, liquor productivity and inventory productivity in Alumina refinery aiming to substantial reduction in specific energy consumption thereby profitability of the plant. Also, we adopt chemical cleaning procedures particularly for descaling the tanks and pipelines of white areas of the plant at faster rate. It is always better to attain high productivity but not at the cost of safety and environment under any circumstance. In present post, we will discuss on the technical reasons for the failure of tankages in Alumina refinery and the possible control measures to avoid such failures in future.

In a few Alumina refineries of the World, failure of caustic storage tanks have been seen because of the circumferential cracking of vessels mainly at the welding zones caused by stress corrosion. The analytical results of the samples collected from the failure areas of the vessels clearly reveal that the Caustic soda at high concentration and high temperature enters the minute weld joints by capillary action and dissolves iron of the vessel progressively due to formation of Sodium Ferrate which develops cracks ultimately causing sudden failure of the storage vessel.

The abnormal behavior of concentrated Caustic soda at high temperature causing destructive cracking is termed as 'Caustic stress corrosion' or 'Caustic Embrittlement'. Caustic embrittlement generally occurs at weld joints, rivets and bends which are under stress. Detailed investigations such as visual, microscopic and metallographic examinations have clearly revealed that circumferential cracks are initiated at high temperature zone and propagated through grain boundaries.

Findings of various test work of fracture morphology confirm that such cracking vis-a-vis failures are mainly due to Caustic embrittlement owing to erraticbehavior of Caustic soda at high concentration and high temperature.

In order to avoid / minimize corrosion and stress fracture risks in unlined steel tankages storing concentrated NaOH must not exceed the temperature of 45oC. 
The Caustic solution used for chemical cleaning of White area tanks, equipment and pipelines should be prepared by mixing fresh Caustic lye in Spent liquor to attain the resulting concentration of NaOH at around 400 gpl (max.). It is also recommended to ensure the temperature of this resulting solution below 82.2 degree C (180 degree F) as precautionary measure as the cracking in metal develops at accelerated pace in fresh caustic environment at temperature above 90 degree centigrade.

The test work confirms that Carbon steel is less susceptible to caustic compared to stainless steel because the cracking in carbon steel is generally inter granular. Carbon steel is considered to be most favorable material for Alumina refinery.

Rajendra Kunwar
CETI Enterprises

Saturday, March 28, 2020


Hi Friends,

Given below please find the detailed Content Sheet of our recently published book on Alumina Technology. The content of the book has been appreciated by global Bauxite-Alumina-Aluminium fraternity.

In case, you wish to have any clarification / confirmation on any issue, it would be our pleasure to furnish thew same.
Best regards.

Rajendra Kunwar
Principal Consultant-Engineering
CETI Enterprises, India.


1.                     Introduction
1.1.                  Overview
1.2.                  Emerging Challenges
1.2.1.              Efficient Process Technology
1.2.2.              Rugged Design of Residue Sorage
1.2.3.              Compact Design of Equipment
1.2.4.              Optimized Plant Layout
1.2.5.              Zero Effluent Discharge
1.2.6.              Planning for Development of Green Belt
1.2.7.              Optimized Capex and Opex
1.3.                  Key Objectives
1.4.                  Acknowledgements

2.                     Raw Materials                                                                                           
2.1.                  Bauxite
2.1.1.              Specific Consumption
2.1.2.              Typical Specifications
2.1.3.              Quality Control Method
2.1.4.              Bauxite Reserves in the World
2.1.5.              Bauxite Reserves in India
2.1.6.              Brief About Gibbsitic Bauxite and Laterite
2.1.7.              Beneficiation of Bauxite
2.2.                  Caustic Soda
2.2.1.              Specific Consumption
2.2.2.              Typical Specifications
2.2.3.              Quality Control Method
2.3.                  Burnt Lime
2.3.1.              Specific Consumption
2.3.2.              Typical Specifications
2.3.3.              Quality Control Method
2.4.                  Fuel Oil
2.4.1.              Specific Consumption
2.4.2.              Typical Specifications
2.4.3.              Quality Control Method
2.5.                  Coal
2.5.1.              Specific Consumption
2.5.2.              Typical Specifications
2.5.3.              Quality Control Method
2.6.                  Flocculent
2.6.1.              Specific Consumption
2.6.2.              Typical Specifications
2.6.3.              Quality Control Method
2.7.                  Synthetic Filter Cloth
2.7.1.              Specific Consumption
2.7.2.              Typical Specifications
2.7.3.              Quality Control Method

3.                     Process technology
3.1.                  Alumina technology overview
3.2.                  Process technology considerations
3.3.                  Quality of Alumina
3.3.1.              Specifications of Metallurgical grade alumina
3.3.2.              Applications of Smelter grade alumina
3.4.                  Technological options for design of Alumina refinery
3.4.1.              Bauxite crushing
3.4.2.              Bauxite grinding
3.4.3.              Desilication, digestion and slurry flashing
3.4.4.              Residue thickening, washing and disposal
3.4.5.              Heat interchange system
3.4.6.              Precipitation and hydrate classification
3.4.7.              Calcination System
3.5                   Recommended process route
3.6                   Technological  & Design features of units
3.6.1                Basic considerations for design of bauxite crushers
3.6.2                Principles of Desilication process
3.6.3                Significance of sodalite factor
3.6.4                Impact of dissolved silica in pregnant liquor on product quality
3.6.5                Desilication methods
3.6.6                Design of efficient digestion system
3.6.7                Techniques of liquor decantation and residue washing
3.6.8                TCA as filter aid for polishing filtration
3.6.9                Heat interchange system
3.6.10             Principles of hydrate precipitation
3.6.11             Techniques of hydrate classification
3.6.12             Multiple effect evaporation system
3.6.13             Hydrate washing and filtration
3.6.14             Energy efficient calcination system
3.7                   Technology and Equipment Oriented Unit Areas
3.8                   Major process control parameters
4.                     Plant Design Criteria
4.1                   Basic design guidelines for green-field Alumina refinery
4.1.1                Reserves and quality of Bauxite
4.1.2                Fixation of plant capacity
4.1.3                Product-mix and product specifications
4.1.4                Finalisation of production process route
4.1.5                Sizing of plant and equipment
4.1.6                Safety and pollution control measures
4.2                   Design criteria for Residue storage pond
4.2.1                Location of residue storage pond
4.2.2                Natural topography
4.2.3                Characteristics of soil
4.2.4                Volumetric capacity
4.2.5                Rain water drainage
4.2.6                Geo-textile lining
4.2.7                Adequate free board
4.2.8                Proper fencing of area
4.3                   Plant availability, design margin and turn down ratio
4.3.1                Overall availability of plant
4.3.2                Design margin
4.3.3                Turndown ratio
4.4                   Major efficiency parameters
4.4.1                Overall alumina recovery
4.4.2                Total soda loss
4.4.3                Liquor productivity
4.4.4                Fuel for calcination
4.4.5                Total process steam
4.5                   Basic terminology used in Alumina refinery
4.5.1                Solid concentration in slurry
4.5.2                Liquor concentration
4.5.3                Plant causticity
4.5.4                Alumina to caustic ratio
4.6                   Plant operating schedule
4.7                   Critical technical data
5.                     Design of Equipment & Facilities
5.1.                  Design of critical equipment
5.1.1                Sizing of liquor decanters
5.1.2                Sizing of residue washers
5.1.3                Sizing of security filters
5.1.4                Design of rotary vacuum drum filters
5.1.5                Design of rotary vacuum disc filters
5.1.6                Design of horizontal rotary vacuum filters
5.1.7                Design of multiple effect evaporators
5.2.                  Design of Tailor-made Equipment
5.2.1                Design of Bauxite grinding mills
5.2.2                Design of Bauxite slurry heat exchangers
5.2.3                Design of Desilication tanks
5.2.4                Design of Digestion vessels
5.2.5                Design of Slurry flash tanks
5.2.6                Design of Condensate flash tanks
5.2.7                Design of Vacuum flash tanks
5.2.8                Design of Liquor storage tanks
5.2.9                Design of Primary hydrate settlers
5.2.10             Design of Slurry mixing agitators
5.2.11             Design of Plate heat exchangers
5.2.12             Motor rating calculations for Centrifugal pumps
5.2.13             Motor rating calculations for Air blower
5.2.14             Guidelines for design of Vacuum pumps for Evaporators
5.2.15             Design guidelines for belt conveyors
5.3.                  Equipment sparing basis
5.4.                  Design Guidelines for sizing of Pipelines
5.4.1                Design Guidelines for sizing of pipelines
5.4.2                Material of construction for pipes
5.4.3                Guidelines for colour coding of pipelines
5.5.                  Design Guidelines for pipe racks
5.6.                  Guidelines for selection of valves
5.7.                  Guidelines for thermal insultation
5.8.            Methodology for estimation of paint requirement

6.                     Design of Utilities and Services
6.1.                  Design guidelines for Co-generation plant
6.1.1                Design basis for Co-generation plant
6.1.2                Condensate returns to Boilers
6.1.3                Electrical power requirement
6.1.4                Design basis for Co-generation plant
6.1.5                Guidelines for Stack height calculations of boilers
6.2.                  Design of Raw Water Supply System
6.2.1.              Quality Specifications of Industrial Water
6.2.2.              Estimated Water Requirement
6.2.3.              Quality specifications of Drinking water
6.2.4.              System Design Calculations for Water supply system
6.3.                  Design Guidelines for Cooling Towers
6.4.                  Design Guidelines for Firefighting System
6.5.                  Design Guidelines for Power Receiving & Distribution System
6.5.1.              Power Control Center
6.5.2.              Motor Control Center
6.5.3.              Diesel Generating Set
6.5.4.              Guidelines for Selection of Starters and Motors
6.6.                  Design Guidelines for Instrumentation and Control System
6.6.1.              Bauxite Crushing, Grinding and Desilication Area
6.6.2.              Digestion, Heat recovery & Sand Washing Area
6.6.3.              Liquor Decantation and Residue Washing Area
6.6.4.              Security Filtration and Precipitation Area
6.6.5.              Evaporation and Liquor Preparation Area
6.6.6.              Product Classification, Washing and Calcination Area
6.7.                  Central Control Room and Data Storage System
6.7.1.              Data Storage System
6.7.2.              Visual Display System
6.7.3.              Report Generation System

7.                      Specifications of Equipment and Motor List
7.1.                   Specifications of plant and equipment
7.1.1.               Technical specifications of secondary crushers for bauxite
7.1.2.               Technical specifications of ball mills
7.1.3.               Technical specifications of liquor to ball mill heat exchangers
7.1.4.               Technical specifications for bauxite slurry heat exchangers
7.1.5.               Technical specifications agitators for pre-desilicators
7.1.6.               Technical specifications of 1st stage regenerative slurry heat exchangers
7.1.7.               Technical specifications for 2nd stage regenerative slurry heat exchangers
7.1.8.               Technical specifications for 3rd stage regenerative slurry heat exchangers
7.1.9.              Technical specifications for live steam slurry heat exchangers
7.1.10.            Technical specifications of Digesters
7.1.11.            Technical specifications of sand cyclones
7.1.12.            Technical specifications of sand classifier
7.1.13.            Technical specifications for rake mechanism for liquor decanters
7.1.14.            Technical specifications for rake mechanism for residue washers
7.1.15.            Technical specifications of rotary vacuum drum filters
7.1.16.            Technical specifications of Evaporators
7.1.17.            Technical specifications of hydroclones for hydrated alumina
7.1.18.            Technical specifications of auto dumping security filters
7.1.19.            Technical specifications of vacuum disc filters
7.1.20.            Technical specifications of horizontal rotary vacuum disc filters
7.1.21.            Technical specifications of Alumina calciners
7.1.22.            Technical spefcifications of pumps
7.1.23.            Technical specifications of agitators
7.2.                  Drive motor list of plant and equipment
7.3.                  Equipment requiring emergency power supply

8.                      Design Features of Civil and Structural Work
8.1.                   Civil Work in Alumina Refinery
8.1.1.               Geo-technical characteristics of soil
8.1.2.               Design features of civil work
8.2.                  Design features of structural work
8.2.1                Process equipment and storage tanks
8.2.2                Structural buildings and storage sheds

9.                     Specialty Grade Products
9.1.                  Chemical grade bauxite
9.1.1.        Quality specifications
9.1.2.        Main uses
9.2.                  Refractory grade calcined bauxite
9.2.1.        Quality specifications
9.2.2.        Main uses
9.2.3.        Market potential
9.2.4.        Production process
9.3.                  Abrasive grade calcined bauxite
9.3.1.        Quality specifications
9.3.2.        Main uses
9.3.3.        Market potential
9.4.            Cement grade bauxite
9.4.1.        Quality specifications
9.4.2.        Properties and Uses
9.5.            Chemical grade hydrate
9.5.1.        Product specifications
9.5.2.        Production process
9.5.3.        Industrial applications
9.5.4.        Packing and transport
9.6.            High purity hydrate
9.6.1.        Product specifications
9.6.2.        Production process
9.6.3.        Industrial applications
9.7.            Dry coarse hydrate
9.7.1.        Product specifications
9.7.2.        Production process
9.7.3.        Industrial applications
9.8.                  Superfine hydrate
9.8.1.        Product specifications
9.8.2.        Production process
9.8.3.        Industrial applications
9.9.            Fire retardant filler grade hydrate
9.9.1.        Product specifications
9.9.2.        Production process
9.9.3.        Industrial applications
9.10.          Pharmaceutical grade hydrate
9.10.1.      Product applications
9.10.2.      Production process
9.10.3.      Industrial applications
9.11.          Light hydrate
9.11.1.      Product specifications
9.11.2.      Industrial applications
9.12.          Low soda high alpha alumina
9.12.1.      Product specifications
9.12.2.      Production process
9.12.3.      Industrial applications
9.13.          High purity high alpha alumina
9.13.1.      Product specifications
9.13.2.      Industrial applications
9.14.          Activated alumina
9.14.1.      Product specifications
9.14.2.      Production process
9.14.3.      Industrial applications
9.15.          Tabular alumina
9.15.1.      Product specifications
9.15.2.      Production process
9.15.3.      Industrial applications
9.16.          Refractory grade alumina
9.16.1.      Product specifications
9.16.2.      Industrial applications
9.16.3.      Production process

10.                   By-Products & Alumina Chemicals
10.1.                Vanadium Sludge
10.1.1.      Quality specifications
10.1.2.      Main uses
10.1.3.      Production process
10.2.          Vanadium Pentoxide
10.2.1.      Quality specifications
10.2.2.      Main uses
10.2.3.      Production process
10.2.4.      Market potential
10.3.          Gallium metal
10.3.1.      Characteristics of gallium
10.3.2.      Main applications
10.3.3.      Production process
10.3.4.      Purification of Gallium
10.3.5.      Storage and transportation
10.4.          Bauxite residue
10.4.1.      Residue generation rate
10.4.2.      Composition of bauxite residue
10.4.3.      Main uses
10.5.          Ferric alum
10.5.1.      Product specifications
10.5.2.      Uses of Ferric alum
10.5.3.      Market potential
10.5.4.      Production process
10.6.          Non-Ferric alum
10.6.1.      Product specifications
10.6.2.      Main applications
10.6.3.      Market potential
10.6.4.      Production process
10.6.5.      Key design guidelines for plant
10.7.          Zeolite
10.7.1.      Types of zeolite and uses
10.7.2.      Specifications of Zeolite-4A
10.7.3.      Global market potential
10.7.4.      Production process
11.                   Basic Process Calculations
11.1.                Material flow balance
11.2.                Alumina Balance
11.3.                Breakup of process steam requirement
11.4.                Technological water balance
11.5.                Caustic balance
11.6.                Bauxite consumption factor
11.7.                Residue factor
11.8.                Alumina extraction efficiency
11.9.                Liquor productivity
11.10.             Sodalite factor
11.11.             Chemical soda loss

12.                   Pre-Investment Studies
12.1.          Project conceptualization
12.2.          Market perspective
12.3.          Characterization and cost of bauxite
12.3.1.      Characterization of bauxite
12.3.2.      Mining cost of bauxite
12.4.          Process technology
12.5.          Land requirement and site selection
12.5.1.      Land requirement
12.5.2.      Site selection
12.6.          Capital cost estimate
12.6.1.      Enabling works
12.6.2.      Land and site development
12.6.3.      Process Know-how and engineering
12.6.4.      Civil & structural work
12.6.5.      Plant & machinery
12.6.6.      Electricals, instrumentation and controls
12.6.7.      Piping & valves
12.6.8.      Cogeneration plant
12.6.9.      Cranes and hoists
12.6.10.    Erection work
12.6.11.    Pre-operative expenses
12.6.12.    Margin money for working capital
12.6.13.    Provision for contingencies
12.6.14.    Sample capital cost estimation
12.7.          Production cost
12.7.1.      Variable cost
12.7.2.      Fixed cost
12.7.3.      Sample production cost calculations
12.8.          Financial analysis
12.9.          Financial results
12.10.       Sensitivity analysis
12.11.       Implementation schedule
12.12.       Conclusions and recommendations

13.                   Engineering Approach
13.1.          Basic engineering
13.2.          Detail engineering
13.2.1.      Review of basic engineering
13.2.2.      Preliminary drawings and documents
13.2.3.      Contracting and procurement
13.2.4.      Inspection and expediting
13.2.5.      Construction and erection drawings
13.2.6.      As-built drawings.