PRE- FEASIBILITY REPORT (In terms of provision of EIA Notification 2006)

For

1 MTPA (2 X 0.51 million TPA) Ammonium Phosphate Fertilizer Plant

AT

Village - Biliya,

Tehsil - Chittaurgarh District- Chittorgarh

Rajasthan

By:

HINDUSTAN ZINC LIMITED,

Yashad Bhawan Udaipur - 313 004

Rajasthan

Submitted to:

Ministry of Environment, Forest and Climate Change

New Delhi

October 2016

2

TABLE OF CONTENT

Sr. No.

Chapter

Page No

1

Executive Summary

3

2

Introduction of Project

4

3

Project Description

5

4

Site Analysis

25

5

Planning

29

6

Rehabilitation and Resettlement (R&R) Plan

30

7

Project Schedule and Cost Estimates

30

8

Analysis of Proposal

30

3

1. Executive Summary

• Hindustan Zinc Limited (HZL) is Asia’s largest Non-Ferrous Metal producer of

Zinc and Lead, Head quartered in Udaipur, Rajasthan. HZL is world's second

largest integrated producer of with a global share of approximately 6.0% in

Zinc.

• HZL has its operations in exploration, mining, ore processing, smelting and

refining of Zinc & Lead. It is also a major producer of Sulphuric Acid, as a by-

product of Zinc-Lead Metal processing. HZL also has interest in Wind and

Thermal Power Generation.

• Zinc-Lead Ore beneficiation commenced at Zawar Near Udaipur in the year

1950 - under the name of ‘Metal Corporation of India (MCI). In the year 1966,

the Government of India took over the activities of MCI and Hindustan Zinc

Limited was formed. The Government of India has disinvested HZL in April

2002. HZL since 2002 is a Vedanta Group Company with 65% stake and 29%

stake with Govt. Of India and 6% with others.

• Hindustan Zinc has now proposed to set up an Ammonium Phosphate

Fertilizer Plant at Village - Biliya, Tehsil/District – Chittorgarh to have a

forward integration in product value chain by converting its own generated

Sulphuric acid & local rock phosphate available with RSMM.

4

2.0 INTRODUCTION OF PROJECT

2.1 Identification of Project and Project Proponent:

2.1.1 Identification of Project

Hindustan Zinc Limited operates a Primary Lead Zinc Smelter of production

capacity 0.525 Mtpa of Zinc, 0.85 Mtpa of Lead and 0.8 Mtpa of Sulphuric Acid

and CPP of 274 MW located at Chanderia near Chittorgarh, Rajasthan. The

proposed project is for installing a Di-ammonium Phosphate Fertilizer plant of

capacity 2 X 0.51 MTPA along with 2 X 0.24 Mtpa Phosphoric acid plant, 2 X 9000

TPA Aluminum Fluoride plant along with off sites & utilities facilities.

In this process, Sulphuric acid produced at Chanderia Lead Zinc Smelter shall be

converted to Phosphoric Acid and further to Di-ammonium Phosphate(DAP)

fertilizer/NPK/Ammonium Sulphate by granulation with Ammonia & Potash. The

project shall be installed at village Biliya adjacent to Chanderia Lead Zinc

Smelter. The bi-product Fluoro-Silicic Acid shall be converted to Aluminum

Fluoride & Gypsum shall be sold to local Cement producers.

2.1.2 Project Proponent

Hindustan Zinc Limited is among the largest producer of Zinc-Lead-Silver in India

and also a major producer of Sulphuric acid, with total metal production of over

1.14 Mtpa and Sulphuric Acid production of over 1.5 Mtpa. The Zinc Smelter at

Chanderia is operational since 1989 and has expanded from an initial capacity of

0.1 Mtpa to 0.525 Mtpa in 2009. It has a combined metal capacity of 0.625MTPA

HZL has secured agreement with RSMM (Rajasthan State Mines & Minerals) for

the supply of 4 lac MTPA rock phosphate concentrate ( 30% grade) and balance

shall be sourced from International market. The Sulphuric acid produced from

Chanderia Lead Zinc Smelter shall be converted to Phosphoric Acid and the

additional acid required shall be sourced from the HZL’s other Zinc smelter sites

in Rajasthan.

The Di-ammonium phosphate (DAP)/NPK/APS fertilizer will cater to domestic

market & thus reduce dependency on import market

2.2 Brief Description of nature of Project

It is proposed to install the following facilities:

TABLE-2.3

Project Facility Capacity Technology Purpose

Phosphoric Acid Plant (PAP)

2 x 240,000

TPA

Phosphoric

Acid

Hemi-

Dihydrate

Technology

(HDH)

To convert rock

phosphate by

reacting with

sulphuric acid

into marketable

product catering

to Fertilizer

Industry.

5

Di-ammonium

Phosphate(DAP) Plant

N:P:K(10:26:26)/(12:32:16)

2 x 5,10,000

TPA DAP

2 x 5,00,000

TPA

Pipe reactor

technology

INCRO pipe

reactor

Low recycle,

better emission

control

Product shift

based on market

demand

Ammonium Phosphate

Sulphate (20:20:0 /

20:20:0:13)

2 X 2,00,000

TPA

Product shift on

market demand

Aluminium Fluoride (AF) 9000 TPA LBD/HBD

technology

Convert Fluoro-

Silicic Acid to

Aluminium

Fluoride(ALF3)

2.2.1 Brief Description of Process

2.2.1.1 Phosphoric Acid Plant

Phosphoric acid shall be produced using Hemi-Dihydrate technology, which is a

combination of Hemi-hydrate Technology & Di-Hydrate technology. Crystal

formation in first stage is in the form of Hemi-hydrate which in transformation

stage crystal will get converted to Di-Hydrate form. Phosphoric acid produced will

have the P2O5 concentration in range of 52-54%. Hemi-Dehydrate technology is

the best available technology for phosphoric acid production. During the

production of Phosphoric acid gypsum is produced & fluorine is evolved in the

form of hydrofluoric acid vapours. This vapour is scrubbed in a scrubbing tower to

produce Hydro fluoro-silicic acid. The Hydrofluoro silicic acid produced is used to

produce Aluminium fluoride by reacting with Aluminium hydroxide.

2.2.1.2 Ammonium Phosphate Fertilizer plant

Ammonium phosphate is produced by reacting ammonia with phosphoric acid.

Mono ammonium phosphate (MAP) is formed which is double ammoniated in a

rotary granulator to form DAP. Granules with high moisture are fed to a rotary

hot air dryer where the DAP granules are dried and subsequently cooled in

another air cooler. In the process, dried granules are screened for the product,

fines and oversize. Oversize granules get crushed in a chain mill further and

recycled back to granulator along with fines. During the process emissions are

formed from granulator dryer and cooler. In order to meet the environmental

norms gas venture scrubbers & Cyclones are installed to cut back the emissions

and recycle back the collected material to the system. Final product is bagged

and dispatched for marketing in 50 kg HDPE bags.

Same granulation plant is also designed to produce different grade of compound

fertilizers like 10:26:26,12:32:16 & Ammonium phosphate sulphate (20:20:0

/20:20:0:13) by changing the mole ratio of ammonia and phosphoric acid and by

adding Potash ( MOP, Potassium Chloride)

6

The same facility shall be used to produce phosphate fertilizer products mix

namely DAP( Di-ammonium Phosphate) 18: 46: 0 ; APS (Ammonium Phosphate

Sulphate) 20: 20: 0 & 20: 20: 0: 13; NPK (12:32:16 / 10:26:26)

2.2.1.3 Aluminium Fluoride Plant.

During the process of Phosphoric acid production, fluorine gas evolves as hydrofluoric

acid fumes which get scrubbed with water to produce Hydro-fluorociclicic acid. Hydro-

flurosilicic acid is a feed sitcom for producing Aluminium fluoride by reacting with

Aluminium Hydroxide. The reaction shall produce silica which gets used back in

Phosphoric acid plant

2.3 Need for the Project and its Importance to the Country

2.3.1 Ammonium phosphate Fertilizer

DAP / NPK / APS are the most widely used phosphate fertilizer for agricultural

application which gives nitrogen, phosphorous & potash and micro nutrient

sulphur. Presently, India is importing over 5 Mtpa DAP/NPK as the current

capacity of the DAP/NPK production is limited due to the non availability of good

grade rock phosphate & sufficient sulphuric acid.

2.4 Demand & Supply Gap

As per Government of India, demand of domestic market for Phosphatic fertilizer

is 11 Million TPA and domestic production is only about 4 Million TPA.

2.5 Domestic Market

India is a net importer of DAP fertilizer. India’s current consumption of DAP/NPK

fertilizer is OVER 11 Million TPA. Rajasthan state has no DAP fertilizer

manufacturing facility at present. Current annual requirement of DAP is around

0.6 Million TPA.

2.6 Employment Generation

The proposed project will generate direct employment of approx 250 manpower

including contract labour. It will provide new opportunities for local people also

resulting in indirect employment for more than 1500 manpower. Training

programs will be set up for the development of local community as per the work

requirement.

7

3.0 PROJECT DESCRIPTION

3.1 Type of Project

The project is a category “A” type of project listed under item No.5a, Chemical

Fertilizer, in the Schedule of the EIA notification 2006.

3.1.1 Raw Material Sources

The primary raw materials for the proposed project are Sulphuric Acid, Rock

Phosphate, Ammonia, Potash. Sulphuric Acid produced in the Chanderiya Lead

Zinc Smelter shall be completely utilized and the short fall shall be sourced from

the other Zinc smelters of Hindustan Zinc Limited in Rajasthan.

Rock Phosphate requirement shall be sourced from RSMM and the shortfall shall

be resourced from international / domestic market.

Ammonia shall be imported from international & domestic market as well. All

imports shall be preferably through the Kandla / Dahej Port in Gujarat.

3.2 Location

Proposed project is proposed to set up at village Biliya, adjacent to our

Chanderiya Lead Zinc Smelter, located about 9 kms from Chitorgarh town.

Figure 3.1

LOCATION MAP OF THE PROJECT SITE

8

Figure- 3.2

DETAILED LAYOUT PLAN OF PROJECT

3.3 Alternate Sites Considered

HZL have considered and evaluated all its Smelters sites (Dariba, Chanderia,

Debari) for freezing the location. Chanderia site have been finalized due to

various supporting infrastructural and operational advantages.

Being close to the proximity of Chanderia Lead-Zinc smelter plant, this project

shall be provided with piped supply of Sulphuric acid, steam, power transmission

line along with water supply arrangement facility.

3.4 Size of Operation

Followings plants are proposed to be set up at Biliya, Chanderia:

TABLE-3.1

PLANT DETAILS

Project Title Capacity

Ammonium phosphate (DAP ) plant 2 x 5,10,000 TPA

Phosphoric Acid Plant 2 x 2,40,000 TPA Phosphoric Acid

N P K (10:26:26 /12:32:16) 2 x 5,00,000 TPA

Ammonium Phosphate Sulphate (APS

20:20:0 /:20:20:0:13:

2 x 2,00,000 TPA

Aluminum Fluoride 2 X 9000 TPA

9

Annual production capacities of proposed project is as follows along with their by-

product

TABLE-3.2

ANNUAL PRODUCTION CAPACITIES OF PROPOSED PROJECT

Type Particulars Capacity (TPA)

Products

Ammonium Phosphate(DAP, 18:46:0) 2 X 5,10,000

NPK(12:32:16 /10:26:26) 2 X 5,00,000

Ammonium Phosphate Sulphate, APS

(20:20:0 / 20:20:0:13)

2 X 2,00,000

Phosphoric acid 2 X 2,40,000*

Aluminium Fluoride 2 X 9,000*

By Product Hydro fluosilicic acid 2 X 9,100

Waste Gypsum 2 X 13,50,000

*Will be consumed within the process and surplus quantity shall be sold.

3.5 Project description with Process details:

Project description:

3.5.1 Phosphoric Acid Plant

Wet Phosphoric acid is produced by three main routes

- Hemi-hydrate Technology, In this process gypsum crystal formation will be in

form of Hemi-hydrate, Acid produced will be 43% grade phosphoric acid. Loss of

P2O5 will be more

- Di-Hydrate technology, this is most common process used in India for

manufacturing of Phosphoric acid. Gypsum crystal is in form of Di-hydrate which

is Phospho-Gypsum. Acid Produced will have the concentration from 26-30%

P2O5.

- Hemi-Dihydrate technology, This is the combination of both the process, Crystal

formation in first stage is in form of Hemi-hydrate and then in transformation

stage crystal will get converted to Di-Hydrate form. Phosphoric acid produced

will be pure and have the P2O5 concentration in range of 42-44%. This is most

efficient process

DH is widely used in India, HDH route is better due to following advantage over

other route

- Better P2O5 recovery

- Low steam consumption

10

- Production of 43% Phosphoric acid ex-Filter

- Better product & Gypsum quality

Hence HDH route is selected for Phosphoric acid production.

3.5.1.1 Details of Process Technology - Hemi-Dihydrate Technology

DH is widely used in India, however, Vedanta Group of company M/S Sterlite

industries Limited’s Phos acid plant is the only plant in India using HDH

technology for Phos acid production. HDH route is selected for Phos acid

production in the proposed project due to following advantage over other route

- Better P2O5 recovery

- Low steam consumption

- Production of 43% Phos acid

- Better product & gypsum quality

FIGURE–3.3-PROCESS FLOW CHART-HDH Process

11

3.5.1.2 PHOSPHORIC ACID PLANT - PROCESS DESCRIPTION

Phosphoric acid plant will consists of following sections

- Rock Phosphate unloading and storage

- Reactor section

- Hemi-Hydrate filtration section

- Transformation section

- Dehydrate filtration system

- Gypsum conveying and gypsum pond

- Clarification & Storage

- Evaporation section

3.5.1.2.1 HH Reaction Section

The design uses three reactors in series with low-sulphate zone and high-

sulphate zone. These reactors, of almost identical operating volume, are fitted

with modern agitators fabricated in duplex material resistant to corrosion and

erosion in the HH slurry. All the agitators of the HH reaction section will be fitted

with foam-breaking blades to reduce defoamer consumption. The design of the

launders and the differential heights between each of the tanks will be

considered so as to enable the foam produced to be tolerated more easily and

reduce the defoamer consumption.

Phosphate rock, from storage, is fed to the first reactor along with a controlled

slurry recycle flow from the high–sulphate reactor. Based on experience there

will be two horizontal centrifugal pumps, one spare, operating with variable

speed control providing the slurry recycle.

The slurry from the first reactor overflows to the second reactor which

complements the low-sulphate volume. This reactor is also fitted with a similar

agitator to the first reactor. There are no feeds to the second reactor.

The third reactor receives the sulphuric acid premixed with the return acid from

the HH filter in a special Zone and as such forms the high-sulphate zone of the

HH reaction section. The heat of reaction is removed by a low-level flash cooler

which re-circulates around this tank. The HH belt filter is also fed from this

reactor by the HH feed pumps.

The gases from the flash cooler go to the vacuum fluorine recovery section. The

dip pipe of the flash-cooler return is situated in an external chamber to prevent

interference with the agitator of the third reactor.

12

3.5.1.2.2 Flash-Cooler Vacuum Section

This section is a vacuum scrubber design having a droplet separation tower to

remove entrained acid carry-over but has a single stage scrubbing tower

operating batch-wise in an automatic programme improving the fluorine recover

efficiency.

The Fluorosilicic acid (FSA) seal tank is initially filled with water to the controlled

level and the recirculation pump started. Water is bled into the system to

maintain the level which decreases due to de-supersaturation of the vapors. As

time goes by the absorption of fluorine compounds increases the strength of the

FSA.

When the desired product strength, 20 – 22 % FSA, is reached the water valve

is closed and the export valve opened. This valve remains open until the level

reaches the low level alarm which closes the export valve and once again allows

the water inlet valve to control the level in the tank. Now the strength of the

circulating liquid is about 5% and the strength progressively increases once

again until the desired product strength is reached when the cycle repeats itself.

After the fluorine recovery section there is a pre-condenser to provide hot water

for filter washing without requiring the use of steam and this is followed by the

main condenser prior to the vacuum pump.

3.5.1.2.3 HH Off-Gas Scrubbing Section

The off-gas from the hemihydrate reactors even though having a relative small

volumetric flow contains relatively high fluorine content and the fluorine must

be removed before being directed to the stack to protect the environment.

This section consists of a first stage to remove entrained acid droplets that could

contaminate the fluosilicic acid (FSA). This first stage has a droplet separator

and a wet scrubber that operates with liquor saturated in FSA and the recovered

droplets with the FSA are returned to the HH reaction system. After the removal

of the acid droplets, the gases pass to two stages of venturi scrubbers. A

variable speed fan draws from the final void tower and the gases are combined

with those from the filtration off-gas section before passing through the main

exhaust fan to the stack Hemihydrate Filtration Section

This section consists of single horizontal belt filter having two counter-current

washes with the final wash being filtrate from the Dihydrate filter. This filter

13

discharges directly into a re-pulp tank the cake being re-slurried by filtrate from

the Dihydrate filter. Off-gas from the filter hood goes to the Filtration Off-gas

Scrubbing Section and fan. The gas joins the other streams from the filters and

the DH Off-gas scrubbers and proceeds to the tail- gas scrubber and stack via

the main exhaust fan.

Self-draining double outlet slurry feed boxes will be provided for the filter and

the wash box shall be of self-draining type with no pockets with integral dams

upstream to prevent mixing of washes. Downstream separately movable dams

will be provided for each box. Vacuum box divisions shall be liquid tight and

with variable positions, provision shall be made for the future addition of a

separator block in the vacuum box touching the belt to allow operation of the

vacuum box at two different vacuums. If implemented, this will enable a final

cake drying zone to be provided. The vacuum box shall be jacketed for hot

water heating if required.

Phosphoric acid from filtrate will be sent to storage/clarifier for 42% phosphoric

acid.

3.5.1.2.4 Hydration Section

This section consists of the two hydration tanks preceded by a re-pulp tank with

intensive agitation so as to fully disperse the HH cake in the re-pulping liquor.

This re-pulp tank also has an inlet for sulphuric acid either premixed with

hydration slurry or re-pulping liquor. Seed crystals from the second hydration

tank are recycled to the first hydration tank by a DH slurry recycle pump. The

first tank will be maintained in depression by the off-gas fan which creates a air-

flow to be able to maintain the temperature of the hydrating slurry below 65°C.

Two new DH filter feed pumps feed the DH filter with two washes and a final

dedicated cake drying section. Off-gas goes to the DH Off-gas Scrubber.

3.5.1.2.5 Dihydrate Filtration Section

This section consists of a single belt filter, fitted with two counter-current

washes and a polishing wash. Hot water from the precondenser is used for the

cloth wash and subsequently for final cake wash. The filtrates are returned to

the hemihydrates filtration section as wash-water and also for sluicing the

discharged hemihydrates cake in the repulp tank. Off-gas from the filter hood

goes to the DH Off-gas Scrubber. A split vacuum box enabling the final cake

drying section to be independent will be used which uses two separate vacuum

14

systems on the filter ensuring minimum moisture in the discharged dihydrate

cake.

3.5.1.2.6 Filtration Off-Gas Scrubbing Section

This section consists of a multi-stage venturi scrubber system with intermediate

void cyclonic towers these gases combine with those of the HH Off-gas

Scrubbing system and the HH filter prior to being routed to the stack via the

main exhaust fan.

3.5.1.2.7 Evaporation Units and Fluorine Recovery

The evaporation section of the Phosphoric Acid Plant, considering single-stage

vacuum evaporators, with carbon tube heat exchangers, is designed to raise the

concentration from 43 % P2O5 to 52-54 % P2O5.

The design consists of a single-stage vacuum evaporators with forced circulation

using a graphite tube heat exchanger, an axial-flow pump and a flash chamber.

The recirculation loop is connected to the base of the flash chamber which is

fitted with a vortex breaker to prevent cavitation of the axial-flow pump.

Low pressure steam is received from the Battery Limits and the evaporative

capacity of the unit is defined by the flow controller on the steam feed.

The level in the flash chamber is controlled by an overflow at such a height that

the boiling of the heated acid prior to entering the flash chamber is prevented.

Weak acid is received from storage/clarifier 42% phosphoric acid and fed into

the acid flow leaving the heat exchanger. The concentrated acid drains via the

standpipe overflow to the agitated product acid seal tank and is pumped to

storage/clarifier 52% phosphoric acid by the concentrated acid pump.

Flurosilicic acid (FSA) is produced in the fluorine recovery section which is a

concurrent absorption tower operating batch wise to improve recovery. The

flashed vapours containing mainly water and fluorine compounds pass through a

high efficiency droplet separator prior to entering the fluorine recovery section.

The acid droplets will report back to the flash chamber. Product is drawn off by

a self regulating variable speed pump and delivered to the storage area.

The residual water vapour, almost free of fluorine compounds, passes through a

direct contact condenser fed with cooling water. The condenser water is

collected in a barometric seal tank which overflows to the return trench and

returned by gravity to the cooling tower.

15

FIGURE-3.4

Process Flowchart for Fluoro-Silicic Acid

FIGURE-3.5

Hemihydrate Filtration

16

FIGURE-3.6

Dihydrate Filtration

FIGURE-3.7

Evaporation

17

3.5.2 PROCESS DESCRIPTION FOR AMMONIUM PHOSPHATE PLANT

Design Basis:

Plant capacity: 5, 10,000 MTPA

Operating days: 330 days per annum

Capacity: 1550 MTPD of Ammonium Phosphate Fertilizer (DAP/NPK/APS)

Operating Hours: 22 hours per day

Hourly capacity: 70 MTPH

Major raw materials: Phosphoric acid, Sulphuric acid, Ammonia, Potash, Filler

Emission level of APF Plant:

Dust: 50 mg / Nm3

Fluorine: 10 mg / Nm3

Ammonia: 5 mg/Nm3

Treated effluent Discharge: Zero

Acid preparation section:

Fresh phosphoric acid is sent to Scrubber Circulation Tank. The Scrubber Pumps send

the scrubber liquor to the Granulator and Drier Scrubber. In the Granulator Scrubber

the acid fixes most of ammonia lost from the Granulator. The scrubber liquor results

partially neutralized and falls by gravity into the Scrubber Circulation Tank. In the Drier

18

Scrubber the acid fixes the ammonia evolved in the Drier and also dissolves the dust of

DAP entrained from the Drier Cyclones. The acid falls by gravity to the Scrubber

Circulation Tank where it is mixed with the acid coming from the Granulator Scrubber.

Pipe reaction & Granulation

From the Scrubber Circulation Tank, the partially neutralized Phosphoric Acid enters the

Pipe Reactor where the acid reacts with ammonia under pressure to a final molar ratio of

2.0 No need for further ammonia addition in the Granulator Bed is required.

The reactions are instantaneous and exothermic and the reaction heat is used to

evaporate part of the water of the phosphoric acid fed to the Plant. This water vapour

and the unreacted ammonia are fed to a stream of air flowing through the Granulator

and are sent to Granulator Scrubber. The APF melt produced in the reactor is sprayed

over the bed of recycle and by temperature effect and moisture it becomes granulated.

To prevent the build up of solids the Granulator walls are lined with selfcleaning rubber

panels that also minimize heat losses.

Solid Handling:

The granulated APF falls into the rotary Drier where it dries in contact With a co-current

flow of hot air coming from the Drier Burner. Product leaving the Drier is sent, through

the Ex-Drier Elevator, to the top of the Screens, where is divided into three streams: the

oversize, the onsize and the fines. The oversize (and some on-size if required) passes

into the Oversize Pulverizers. Crushed materials, fines and the dust collected by the

Drier Cyclones, FBC Bag Filter, and Dedust Bag Filter, are discharged on the Recycle

Conveyor. The on-size product from the Screens falls into a Fluidized Bed Cooler where it

is cooled to the desired temperature. Finally, the product is sent to the storage.

Utilities consumption (per MT of APF)

Electricity 45 kWh

Fuel oil 04 Kg

PROCESS FLOW DIAGRAM: Fig 3.9

19

3.5.3 Aluminium fluoride Plant process

Aluminium Fluoride production from HFA (Hydro Fluoric Acid) route has been considered.

Fluorosilicic Acid (FSA) produced as by-product in Phosphoric Acid plant shall be used as

raw material for the production of HFA / AlF3. AD PROCESS STRATEGIES SARL

Technology has been considered for the AlF3 Plant. The Process Description of the

Technology is given below. Various steps are described below:

3.5.3.1 Anhydrous hydrofluoric acid (AHF) from FSA

HF Gas Generation

Hydrogen fluoride (HF) is produced by the decomposition of an aqueous solution of

Fluosilicic acid in the presence of Sulphuric acid in a stirred reactor under closely

controlled conditions. Strong sulphuric acid 98% is fed and is acting as a dehydrating

agent.

Products of decomposition of fluosilicic acid are gaseous silicon tetrafuoride (SiF4) and

hydrogen fluoride (HF). The HF is adsorbed into the sulphuric acid and leaves the reactor

with the sulphuric acid. Hydrogen fluoride (HF) is recovered by evaporation and dried

with fresh sulphuric acid. A two-stage evaporation system using boiler and stripper

column is used. Gaseous hydrofluoric acid generated as described is then condensed and

20

purified by distillation to obtain the desired product quality and finally is sent to the

intermediate AHF Storage Tank.

H2SiF6.SiF4 (aq.) + H2SO4 = 2 SiF4 + 2 HF (aq.) + H2SO4 (aq.)

Next the Silicon Tetrafluoride (SiF4) gas leaving the reactor after drying column is

absorbed into the Fluosilicic acid (H2SiF6) feed solution to generate additional acid and

silica according to the chemical reaction:

5 SiF4 + 2 H2O = 2 H2SiF6.SiF4 (aq.) + SiO2 (hydrate)

The strong solution of fluosilicic acid is sent to the silicon tetrafluoride reactor.

The diluted sulphuric acid stream obtained after stripper is cooled down prior storage

and recirculation to the phosphoric acid plant.

Flow Sheet Showing Production of AHF from FSA

AHF Liquefaction and Purification

The crude HF gas is sent the purifying column. From this column the gases pass to two

condensers in series, where the bulk of the hydrofluoric acid is liquefied using chilled

water of controlled temperature.

Condensed hydrofluoric acid from the first condenser is send back as reflux to the top of

the purifying column. From the second condenser the partially purified hydrofluoric acid

is fed to a pressurised rectifying column, where light impurities, mainly sulphur dioxide

and silicon tetrafluoride, are removed as overhead stream. The pure hydrofluoric acid

leaves the rectifying column via the distilled acid cooler to AHF storage tank, using the

pressure of the rectifying column as the driving force. The gaseous overhead products

stream from the rectifying column and second HF condenser are passed through a

21

packed H2SO4 absorption column, down which sulphuric acid is circulated to absorb

most of the remaining hydrofluoric acid. A stream containing hydrofluoric acid in

sulphuric acid is then pumped back. Gases leaving the H2SO4 absorption column are

contacted with water in two ejector scrubbers in series. These remove silicon

tetrafluoride as fluosilicic acid. This stream is re-circulated.

Water effluent sent to the neutralisation is adjusted to minimize the losses of fluorine

and decrease the costs of treatment. Tail gases leaving these scrubbers via the tail gas

exhaust fan are given a final cleaning in the central absorption scrubber washed with

water before emission to atmosphere.

AHF Storage

HF sub-cooled is stored under atmospheric pressure in tanks installed inside a larger

containment tank. The heat losses are minimized by drying the air inside the

containment tank. The air is monitored continuously to detect any leaks of HF. A back-

up chiller is provided on emergency power. The system is corrosion free after 20 years

operation.

The product AHF delivered by Containers flows under pressure via the AHF Circulation

Cooler to the AHF Storage Tanks.

The main storage system comprises of AHF Storage Tank(s), T-421 A/B/C, within the

AHF Storage Containment Tank, T-422. The stored acid is re-circulated through the AHF

Circulating Cooler, E-420 and can be cooled down to say +5 to -8 °C according to

coolant.

The combination of storing AHF acid at low temperature within a double skin system

offers maximum safe storage of this dangerous chemical.

The storage system is equipped with adequate pressure control and safety

instrumentation. The gas from the inside of the outer containment is being continuously

dried and sampled for HF. A cabinet including a detector for fluorine is included.

Hardwired level switch is provided to trip in case of high high alarm all feeds of fluorspar,

acid, oleum, acid recycling and any pump that could fill the tanks with AHF.

Double bottom valves welded are provided on each tank for maximum safety. Manual

operated is making the system more simple and more safe to operate.

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3.5.3.2 High-bulk-density Aluminium Fluoride (HBD AlF3) from HF

The Alumina hydrate is stored into the “Day-Shift” Silo (Hydrate Silo). The Hydrate is

discharged batchwise from the Silo by operating the Discharge Screw (Hydrate Silo

Discharge Screw) for feeding the Hydrate Feed Bin.

The Discharge Screw is controlled by switches onto the Hydrate Feed Bin which is

suspended on two Load cells and switch onto the Hydrate Distributor Bin. The Hydrate is

then fed batchwise from the Hydrate Feed bin to the Hydrate Distributor Bin where a

level of hydrate is maintained which acts as a vacuum seal and keeps the vacuum in the

system.

The load cells are used to totalize the alumina fed to the Aluminium Fluoride Reactor. It

is furthermore indicating exactly the capacity of the Aluminium Fluoride Reactor.

The alumina tri-hydrate is fed continuously to the Reactor via two Feed Screws.

Flow sheet Showing Production of AlF3 from AHF

First Hydrate Feed Screw is feeding most of the material and is controlling the

temperature in the top bed. The speed of the Hydrate Feed Screw is adjusted according

to the temperature in the bottom bed and top bed.

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The Feed Screw is feeding the material via a fluidisation cup and this for avoiding the

agglomeration of hydrate especially at start-up.

Hydrate Bottom Feed Screw feeds the bottom bed at a small feed rate for diluting the

bottom bed and for obtaining a lower grade for the aluminium fluoride product. This is

controlled manually by setting the speed of this screw manually.

The reaction can be represented by the following equations:

Al2O3.3H2O = Al2O3 + 3 H2O

Al2O3 + 6 HF = 2 AlF3 + 3 H2O

Since the overall reaction is exothermic, the AlF3 Reactor does not need supplementary

heat during normal operation. During start-up it does need to be preheated using the

Combustion Chamber. This item is also used for keeping warm the aluminium fluoride

Reactor if the feed of HF gas is interrupted. Solids carried out of the Reactor are

recovered by cyclone separators. Under rated capacity, the dust collected in cyclone 1 is

not re-circulated to the Aluminium Fluoride Reactor. Only under high load or if the

quality needs to be improved dusts are re-circulated to the aluminium fluoride reactor

preferably to the top bed if the grade has to be increased and preferably to the bottom

bed if both the grade has to be improved and the content of silica to be reduced

significantly. Whether or not dusts are re-circulated to the Aluminium Fluoride Reactor,

the discharge of dusts from Cyclone directly to product into the Aluminium Fluoride

Cooler, is always operated.

Vacuum is kept at discharges of cyclones by level maintained in Cyclone Bin installed

underneath and equipped with discharge device and valve.

The aluminium fluoride is discharged from the bottom bed of the Aluminium Fluoride

Reactor through the discharge and then cooled down into a fluidised bed cooler to a

temperature preferably lower than 80°C.

The Off-gases from aluminium fluoride reactor after Cyclones are quenched and

condensed in the absorber and then are scrubbed.

The condensation of HF, H2O, etc occurs in the Absorber and HF Scrubber without

addition of water. The concentration of fluorine in the liquor formed provides a good

indication of the efficiency of the reactor and is used for its control.

The diluted acid solution produced will be sent to the neutralization plant or reused.

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The second column is used to remove the traces of Fluorine, S, dusts, etc. This column is

the stand-by unit for the third column in case of fouling and vice versa.

The fluidisation in the Aluminium Fluoride Reactor is maintained by the vacuum obtained

from the operation of a Steam Ejector.

An Absorption System common to the aluminium fluoride plant and hydrofluoric acid is

provided.

Water is sent to the final absorber in order to absorb totally HF and reach the emission

limit for F in the off-gases in all modes of operation of the plant. This effluent water is

also sent to the neutralization plant or reused.

3.6 Raw Material Requirement

TABLE-3.3

DETAILS OF RAW MATERIAL

Plant Capacity Raw Material

(major)

Source Marketing

area of

finished

product

Mode of

transport

Phosphoric

Acid Plant

2 x 2,40,000

TPA

Phosphoric

Acid

Rock

phosphate:

2 X 7,90,000

TPA

Domestic/

import

Own

consumption

in DAP /NPK

Domestic

Pipeline/

Road

Sulphuric Acid

2 X 7,20,000

TPA

Own

Smelters

Ammonium

Phosphate

Plant

2 X5,10,000

TPA

Ammonium

phosphate

Phosphoric

acid:2 X

2,40,000

TPA

Captive

Domestic

market

Rail / Road

Ammonia: 2 X

1,20,000 TPA

Import

Potash: 2 X

1,50,000 TPA

Import

Aluminium

Fluoride

2 X 9000 TPA Fluoro-Silicic

Acid

2 X 9100 TPA

Aluminium

Hydroxide 2 X

9100 TPA

By-product

from

Phosphoric

Acid Plant

Domestic

market

Road

3.7 Resource optimization/ recycling and reuse

The presence of Fluoride in Rock Phosphate will be recovered as a value product

of Aluminium Fluoride and Fluoro Silicic Acid. Phospho Gypsum generated as a

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waste shall be utilized in Cement Industries. The waste water generated from the

proposed project shall by treated through appropriate recycling and reuse.

3.8 Water & Power Availability & Source

3.8.1 Water Availability

HZL has approvals for withdrawal of water from the Ghosunda dam and the same

shall be used for the proposed project. The water from these sources shall be

appropriately treated to improve the quality to suit the requirement of the

proposed project.

Chttorgarh town is also in the final stage of commissioning of its 1st kind STP

plant of 10 KLD which is also being discussed with for 100% utilization at the

plant

3.8.2 Power Availability

A total power requirement of 17 MW for the proposed projects shall be sourced

from the state grid through the Ajmer Vidyut Vitaran Nigam Limited (AVVNL),

Rajasthan

Emergency Power Generation

In addition to the existing emergency backup power source, the following Diesel

Generator (DG) sets have been proposed for the proposed project.

1) 2 no x 2500 KVA emergency DG

3.9 Wastewater Generation and its Management

The total effluent generations from the project is are as given below;

TABLE-3.4

EFFLUENT GENERATIONS FROM THE PROJECT

S. No. Plant Effluent generation (cum/h)

1 Phosphoric Acid Plant 2 X 100

2 Fertilizer Plant 0

3. Aluminium fluoride plant 2 X 100

Total 2 X 200

The effluent generated from phosphoric acid plant will be treated to remove

fluoride and will be treated to neutralize the acidity.

Effluent Treatment Plant shall be installed to treat the effluents generated from

the proposed project and other associated services to a reusable quality and

completely reused to maintain a zero discharge operation.

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Sewage Treatment Plant shall also be installed to treat the domestic effluent

generated. Treated water shall be utilized for plantation and other uses.

4.0 SITE ANALYSIS

4.1 Connectivity

Project location is on the well connected with National highway NH-79 at

(distance 5.0 kms). The nearest Railway head is at Chanderia Station, about 2.5

kms on Chittorgarh- Delhi Route.

4.2 Land Form, Land use and land ownership

4.2.1 Land Form

The proposed land terrain is flat and developed.

4.2.2 Land Use

The proposed project site is an industrial land.

4.2.3 Land Ownership

Total Land for the proposed project site is owned by Hindustan Zinc limited.

4.3 Topography

Topography of the project site 10 kms radius is shown in the map below

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TOPOGRAPHICAL FEATURES OF THE AREA

4.4 Existing Land Use Pattern

The total available area at village Biliya is 105.05 Ha. This area is classified under

Industrially Developed Area (IDA). The details are as given below:

Land use pattern Land use *Details (Hectare)

Process & Ind. building IDA -

HW disposal facility IDA -

Green belt -

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Open area 105

Total 105

4.5 Existing Infrastructure and Amenities

The following infrastructure exists:

- Metal top road connecting to the nearest NH-76 (0.5 Km) away.

- Well connected internal roads and internal electrical lines

- 132 kV Electrical Substation Township and guest house facility

- Hospital

- Drinking water facility

- Recreational facility with well developed township

- Post office, Bus station, Railway station, Banks, shopping complex,

community halls, Sr.Sec schools, worship places etc, exists.

The existing infrastructure shall be upgraded to cater to the requirements of the

proposed project where ever necessary.

4.6 Soil Classification

The texture of soil is mostly clayey in the buffer area. The common color of the

soil ranged from brown to brownish black.

4.7 Climatic data and secondary sources

The details on climatic data from primary and secondary sources are as given in

following table:

TABLE-4.1

Particulars Details

Location Village - Biliya, Chittorgarh

Project Area Coordinates

Latitude Range 24°58’00” N to 24°58’30” N

Longitude Range 740 39’ 50” E to 740 40’ 20” E

Geographical Location in Toposheet

Elevation above Mean Sea Level 392 m

Climatic Conditions as per IMD- Chittorgarh(Dabok)

a. Temperature Maximum- 42.30C, Minimum- 2.70C

b. Relative Humidity Maximum- 85% , Minimum.- 24%

c. Wind Speed Range 2.6 to 11.7 Kmph

d. Annual Rainfall 650 mm (average)

e. Predominant wind direction N and NW

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Particulars Details

Nearest Highway • NH-79 (5 km)

• NH-76 (5 km)

Nearest Railhead Chanderiya (3.0 km, SW)

Nearest Railway Line Udaipur – Delhi line (2 kms)

Nearest Airport Maharana Pratap Airport – Udaipur 110

km

Other Historical / Religious Places Chittorgarh Fort (6.5 km, SSW)

Defense Installations Nil

Ecologically sensitive areas /

protected areas as per Wildlife

Protection Act 1972 (National Parks

/ Wild life sanctuaries / bio-sphere

reserves / tiger reserves)

No National Park.

Bassi wildlife sanctuary is more than 10

km from the plant

Reserved / Protected Forest • RF near Chanderiya Village (3.8

km, SW)

• RF near Bhiliya khera Village (3.3

km, E)

• RF near Gwalaji ka khera (5 km,

WNW)

• RF Chittorgarh Fort (8.0 km, S)

• RF Era (9 Km, NW)

Nearest Village Biliya - 1 kms

Nearest Town/City and Tourist

place

Chittorgarh (9.0 km SSW), population of

1,16,530 (2011 census)

Hills / Valleys Low altitude hills on the SE site of the

project site.

List of Industries • Hindustan Zinc Ltd., Chanderiya

lead & Zinc Smelter (Adjacent)

• Birla Cement works (2.5 km, SSW)

• Marble processing units (4.6 km

SSW & 0.5 Km N)

Seismicity Zone-II (IS 1893 Part-I:2002)

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4.8 Social Infrastructure available

The existing infrastructure in the project site includes the following

• 16 bed hospital with ambulance

• Bank

• Post Office

• Fire Station

• Senior Secondary School

• Police Station

• Shopping Complex

• Sports Infrastructure (Stadium & Camps etc)

• Self Help Groups

• Community Halls

• Primary Health Care Centers

5.0 PLANNING

5.1 Planning Concept

The area comes under the village Biliya and the city limits of Chittorgarh starts at

a distance of about 9 kms from the project site. There are many educational

institutes, medical and hospital facility, industrial area, markets developed within

the 10 Km radius. The airport is located at a distance of 110 kms form the project

site. The proposed site is well connected by basic infrastructures like rail, road,

electricity and water, maintained by Govt of Rajasthan.

5.2 Population Projection

Population

The population of the village Biliya as per census 2011 is 1475.

5.3 Land Use planning

The entire 105.05 Ha. of the property is an industrial land use. The land falls in

the villages of Biliya Gram Panchayat.

No additional land is proposed to be acquired for the project.

5.4 Assessment of Infrastructure demand (Physical and social)

For the proposed project there shall be demand for the following physical and

social infrastructure.

i) Railway Network – Railway siding within the project area will be

developed.

ii) Water Supply-the existing infrastructure will be upgraded from Gosunda

dam & Chittorgarh STP.

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iii) Power transmission – New transmission line will be laid out from existing

substation / switch yard through Rajasthan State Electricity Board

iv) Housing – Existing Township will be upgraded to partly accommodate the

additional manpower and the remaining will be catered by the adequate

infrastructure existing in the city of Chittorgarh.

5.5 Amenities and Facilities

i) Education: There exists a primary and secondary school within the

township. Additionally numerous education facility is available in the city

of Chittorgarh.

ii) Social Infrastructure like Post Office, Bank, Police Station, Bus Station,

Facility Exists and will continue to meet the demand of increased

populace.

iii) Telecommunication, LPG services, Marketing stalls, Sports infrastructure –

exists and shall continue to meet the demand of increased populace.

iv) Recreation- City of Chittorgarh offers adequate recreational facilities.

v) Hospital – existing 16 Beds hospital with ambulance that would be

adequate. There are many hospitals within 5-10 kms distance from the

project site.

vi) Commuting/conveyance- Conveyance system from project site to the

nearby towns and city is adequately developed.

vii) Waste water treatment – the existing sewage treatment facility in the

township shall be upgraded to meet the increased demand.

viii) Municipal Solid waste management – The present infrastructure will be

strengthened.

6.0 REHABILITATION AND RESETTLEMENT (R&R) PLAN

The Entire land required for the project is registered in the name of Hindustan

Zinc limited and does not have any settlement. So there shall be no

Rehabilitation & Resettlement (R&R).

7.0 PROJECT SCHEDULE AND COST ESTIMATES

7.1 Project Schedule

The entire project shall be implemented within 24 months from the date of grant

of Environment clearance

7.2 Capital Cost Estimates

The capital cost of the project is estimated at Rs. 1200 Crore with a payback of

about 6 years.

7.2.1 Expenditure on Environment in Project Cost

The overall cost on measures for the environment protection will be about 3 % of

the total project cost. The cost will include the Pollution prevention and control

measures, Land fill site construction cost, setting up of emission control and

32

environmental monitoring equipments and stations and development of the green

cover as per the statutory.

8.0 ANALYSIS OF PROPOSAL

8.1 Financial Benefit

The proposed project shall generate reduce import of Fertilizer thus saving of

foreign exchange. This will also generate revenue to the state Government as

well as central government. The people around the region will get direct and

indirect employment thus improves the financial status.

8.2 Social Benefits

The proposed project shall further strengthen its committments on CSR

investment for overall upliftment of socio economic index of the communities

around the project site by way of financial and administrative support. The

project will open up large employment opportunities, directly and also indirectly.

There shall be opportunities for entrepreneurs to engage in many service sectors

directly or indirectly associated with the project.

The CSR approach of the company shall be towards sustainable livelihood

management of the community around. There shall be focus on education,

health, sanitation, drinking water, agriculture, water shed management, culture

identity preservation, welfare of socially weaker sections and marginalized

people.

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