Upload
vumien
View
219
Download
4
Embed Size (px)
Citation preview
1
ANNEXURE‐I
DETAILS OF PRODUCTS AND BYPRODUCTS
(EXISTING AS WELL AS PROPOSED)
Sr. No.
Products/By‐Products Units Existing Capacity
Proposed Capacity
Total Capacity after Expansion
1 Soda Ash Plant
A Light Soda Ash TPD 2000 800 2800
B Dense Soda Ash TPD 1200 600 1800
C Vacuum Salt TPD 1600 ‐‐‐ 1600
2 Caustic Soda Plant
A Product
Caustic Soda (100%) TPD 480 270 750
Hydrochloric Acid (100%) TPD 40 240 280
B By‐Products
Chlorine Gas (100%) TPD 425.2 240 665.2
Hydrogen (100%) TPD 12 6.75 18.75
Sodium Hypo Chlorite (100%) TPD 6 6 12
3 Captive Power Plant
Power MW 97.18 100 197.18
4 Chlorine & Hydrogen Derivatives
A Hydrogen Peroxide (100%) TPD ‐‐‐ 84 84
B Epichlorohydrine (ECH) TPD ‐‐‐ 150 150
C Glycerin TPD ‐‐‐ 160 160
D Mono Chloro Acetic Acid (MCAA)
TPD ‐‐‐ 120 120
By‐Products
Hydrochloric Acid (100%) TPD ‐‐‐ 48 48
Mother Liquor of MCAA TPD ‐‐‐ 30 30
Sodium Hypo Chlorite (100%) TPD ‐‐‐ 10 10
Product
E Trichloro Acetyl Chloride (TCAC)
TPD ‐‐‐ 10 10
By‐Product
2
Hydrochloric Acid (100%) TPD ‐‐‐ 9 9
Sodium Hypo Chlorite (100%) TPD ‐‐‐ 1 1
Sodium Bisulfite Solution (100%)
TPD ‐‐‐ 3 3
5 Toilet Soap Plant
Toilet Soap TPD 200 ‐‐‐ 200
Detergent Powder TPD 414.66 ‐‐‐ 414.66
Detergent Cake TPD 414.66 ‐‐‐ 414.66
Fatty Acid TPD 150 ‐‐‐ 150
Glycerin TPD 167 ‐‐‐ 167
6 Bromine Plant
Bromine TPD 10 ‐‐‐ 10
3
ANNEXURE ‐ II
BRIEF PROCESS DESCRIPTION
1. SODA ASH:
Process Description
The global theoretical equation for the production of soda ash, involving sodium chloride
and calcium carbonate is as follows;
2 NaCl + CaCO3 → Na2CO3 + CaCl2
In practice the reaction is not possible and needs the participation of other substances and
many different process steps to get the final product. The first reaction involves absorption
of ammonia in salt solution, followed by reaction of ammoniated brine with carbon dioxide
to obtain ammonium carbonate followed by ammonium carbonate. The continuous
introduction of carbon dioxide injection and cooling the solution, precipitation of sodium
bicarbonate is achieved and ammonium chloride is formed. The chemical reactions of the
process are given below:
NaCl + H2O + NH3 → NaCl + NH4OH
2 NH4OH + CO2 → (NH4)2 CO3 + H2O
(NH4)2CO3 + CO2 + H2O → 2 NH4HCO3
2 NH4HCO3 + 2 NaCl → 2 NaHCO3 + 2 NH4Cl
Sodium Bicarbonate crystals are separated from the mother liquor by filtration, followed by
thermal decomposition to obtain sodium carbonate, water and carbon dioxide. Sodium
carbonate, thus formed is called “light soda ash” because its bulk density is approximately
0.5 t/m3.
2 NaHCO3 → Na2CO3 + H2O + CO2
CO2 is recovered in the carbonation step. The mother liquor is treated to recover ammonia,
by reacting with dry lime followed by steam stripping to recover free gaseous ammonia,
which is recycled to absorption step.
2 NH4Cl + H2O+CaO → CaCl2 + 2 NH3 + 2 H2O
Carbon dioxide and Calcium oxide originate from limestone calcinations CaCO3 → CaO + CO2
Calcium and magnesium which are impurities in the brine are removed by reacting with
alkali and carbon dioxide to produce insoluble salts. Brine purification reactions are
described in the following equations:
Ca2+ + CO32‐ → CaCO3
4
Coke 0.102 MT
Waste water 6.5 m3
Soda ash 1 MT
CaCl2 1.05 MT
CO2 gas 0.415 MT
NH3 gas 0.32 MT Reuse in next operation
Lime Stone 1.75 MT
Ammonia 0.32MT
Water 6 m3
Sodium Sulphide 0.003 MT
Mg2+ + 2 OH‐ → Mg (OH)2
The difference between Light and Dense Soda ash is bulk density & the size of particles.
Dense Soda ash is produced via the monohydrate process. The hot light soda ash discharge
from Calciner is transported via chain conveyors and bucket elevator to Hydrator. In
hydrator Light Soda ash is mixed with water to form monohydrate according to the
exothermic reaction:
Na2CO3 + H2O Na2CO3.H2O The next step is dehydration and drying of the monohydrate in Fluid Bed Dryer according to
endothermic reaction:
Na2CO3.H2O Na2CO3 + H2O
The Dense Soda Ash is cooled and transported to storage to packing plant. The block
diagram of the Soda Ash Manufacturing unit is given in the Figure shown below.
Process
Salt‐ 2 MT
5
Mass Balance:
2. CAUSTIC SODA:
Process Description: The Caustic soda manufacturing technology being used i.e. membrane
technology is completely environment friendly. The by products are hydrogen, chlorine &
sodium hypo chlorite. Hydrochloric acid is manufactured using H2 and Cl2 (produced from
cell house).
Manufacturing process of Caustic Soda involves the following key steps:
Brine Saturation: Desirable circulating rate of brine in saturator is attained by dissolving salt
from solar salt works and depleted brine from the process. The water loss by membrane is
compensated by supply of demineralized water.
Chemical Preparation: In precipitation tanks saturated brine is treated to remove Ca, Mg &
Sulphates by adding Na2CO3, NaOH and Barium Chloride.
Clarification: Flocculants are added to enhance the settling. Impurities are removed in
clarifier. Main impurities are solids which are pumped to sludge filtration unit. Filtrate is
recycled to clarifier.
Filtration: Anthracite filters are used to remove suspended solids.
Secondary Brine Purification: Polishing candle filters and ion exchange system is used for
this process. The objective of producing ultra‐pure brine required for membrane cell
SALT
BRINE PREPARATION
RO / RAIN WATER LIME STONECOKE
LIME KILNS
ABSORPTION
CARBONATION
CALCINATION
DENSIFICATION
STORAGE
WASTE TREATMENT SETTLING OF SOLID
DISTILLATION
COMPRESSION
GAS CONDENSATION
PACKING
FILTERATION
FINAL PRODUCTS
CLEAR LIQ. TO SALT WORKS
AIR
STEAM38-40% CO2
80-90% CO2
PURIFIED BRINECaCl2 Waste
CRUDE BICARBONATE
STEAM
LSA
DSA
LSA
LSA & DSA
MOTHER LIQUOR NH4Cl
AMMONIA GAS
AMMONIA MAKE UP
LIME
CO2 + H2O
STEAM
ZERO DISCHARGE
6
operation is achieved. Polished brine after heating through brine heater is passed through
two ion exchange columns connected in series. The columns have cation exchange resin,
which provides active sites for adsorption of residual calcium and magnesium salts still
present in brine. Brine is passed through heat exchanger for achieving the temperature
required at cell inlet.
Electrolysis: Brine flows into the anode chamber. Cl2 is liberated at the anode surface with
depleted brine left behind. Cl2 and depleted brine overflows from the anode chambers into
the anolyte header. Weak caustic flows into the cathode chamber. H2 is generated at the
cathode surface and OH ions combine with the Na+ ions diffusing through the membrane. A
two‐phase mixture of 32% NaOH and hydrogen overflows into the catholyte header.
Anode Reaction: 2NaCl 2Na+ + Cl2 + 2 e –
Cathode Reaction: 2H2O + 2 e – 2OH– +H2
Overall Reaction: 2NaCl + 2H2O 2NaOH + Cl2 + H2
Catholyte System: In the catholyte header the two‐phase mixture of NaOH and Hydrogen
gets separated. This catholyte stream is tapped as “Product” and fed to the caustic
evaporation unit. Whole stream is not tapped and some part is sent for internal
consumption.
Anolyte Dechlorination: Depleted brine containing dissolved chlorine (called anolyte) is
dechlorinated in two stages: Vacuum dechlorination and chemical dechlorination. A part
stream of chemically dechlorinated brine is be purged out of the system to keep the
sulphate within the desired levels.
Caustic Evaporation Unit: Here the incoming 32% Caustic is concentrated to 50%. The 50%
caustic coming from this unit can be stored in 50% storage tank.
Chlorine Treatment: The water vapor is removed, from the saturated chlorine, using series
of coolers. The gas is then passed through the moist chlorine filter to remove the entrained
brine aerosol. In drying towers 98% H2SO4 is used to dry moist chlorine.
The dried chlorine gas is compressed to the required pressure and then liquefied. Liquid
chlorine from the liquefiers is sent to liquid chlorine storage tanks. Sniff gas from the
liquefier containing inlets and chlorine gas is sent to the HCl synthesis unit. Excess sniff gas,
is diverted to the waste air system.
Hydrogen Treatment: Hydrogen gas leaving the cells saturated with water vapor is cooled.
The cooled gas is passed through filters to remove the NaOH aerosols. Some amount of
7
hydrogen is required for HCl synthesis and a part of the gas is sent to caustic flaking unit to
be used as fuel and a part is sent to hydrogen bottling through hydrogen compressors as
per requirement and the balance hydrogen is vented through with flame arrestor.
HCl Synthesis Unit
Hydrogen is burnt in Chlorine atmosphere and the combustion gases are absorbed in water
to yield a 32% HCl solution.
HCl produced is pumped to HCl head tank from HCl receiver for internal consumption within
plant. The Block diagram showing the Caustic Soda Manufacturing Process is shown in
below figure;
Cl2 Gas 239.33 MT
H2 Gas 7.65 MT
Water‐MT 1.125 Drift loss 65.81 MT
Evp. Loss 742.50 MT
Salt 518.63 MT Salt 41.63 MT‐Water
Na2CO3 2.81 MT‐ Na2CO3
H2SO4‐98% 5.51 MT‐ H2SO4 0.11 MT ‐ Water
A.cellulose 0.10 MT
Flocculant 0.01 MT
NaHSO3 0.06 MT
Process water 2560.66 MT
Sludge 6.525 MT Water ‐ 1.9125 MT
Liq. Effluent 270 MT
CT Blow Down 306.79 MT
Purge Brine 347.63 MT
Water ‐ 270 MT
NaOH‐48% ‐ 546.1MT Water ‐ 284.0 MT
HCL‐32% ‐ 728.9MT Water ‐ 495.7 MT
Hypo – 59.2 MT Water‐MT – 53.3 MT
H2SO4‐78% ‐ 6.9 MT
Water ‐ 1.46 MT
8
Schematic Diagram of Caustic Soda Manufacturing Process
VENT
CAUSTIC TO STORAGE AND
FILLINGSALT SATURATION
BRINE PRECIPITATION
CHLORATE DESTRUCTION
CATHOLYTE SYSTEM
DM WATER/CONDENSATE
CHEMICALS Na2CO3,NaOH SALT
FLOCCULANT
NaHSO3, NaOH 32% SOLUTION
DM WATER
FLAKES STORAGEAND BAGGING
HYDROGEN BOTTLING
FLAKING UNIT
CAUSTIC EVAPORATION
CHLORINE LIQUEFICATION
HYDROGEN TREATMENT
LIQUID CHLORINE STORAGE
CHLORINE FILLING
48.5 / 50%NaOH SOLUTION
BRINE PURIFICATION
(ION EXCHANGE)
BRINE FILTRATION
SLUDGE FILTRATION
BRINE CLARIFICATION
ANOLYTE DECHLORINATION
SLUDGE
CHLORINE COOLING &
DRYING
98% H2SO4
CHLORINE COMPRESSION
ANODE CATHODE+ -
78% H2SO4
H2 TO STACK
HCL FILLING
HCL STORAGE
HCL SYNTHESIS UNIT
HYPO FILLING
HYPOCHLORITE STORAGE
WASTE GAS DECHLORINATION
VENT
SALT SATURATION
BRINE PRECIPITATION
CATHOLYTE SYSTEM
3. CAPTIVE POWER PLANT
In the case of lignite/coal‐fired boilers, steam generation with any of following firing
technology is technically feasible:
• Circulating fluidized bed combustion (CFBC)
• Pressurized Fluidized Bed Combustion (PFBC)
• Integrated Gasification Combined Cycle (IGCC)
• Pulverized Fuel Firing (PF)
Circulating fluidized bed combustion (CFBC) technology is adopted for the proposed
captive power plant. A 100 MW captive power plant turbo‐alternator and 350 TPH + 350
TPH (standby) lignite/coal/petcoke based CFBC Boilers, along with captive power plant
machineries will be installed in order to meet internal steam and power requirement for the
proposed expansion.
The steam generator units proposed for the plant will be compact, semi‐outdoor,
natural/assisted circulation, balanced draft, single drum, water tube type provided with
Circulating Fluidized Bed Combustion system using pan‐leg furnace configuration. In a
9
typical Circulating Fluidized Bed furnace, the lignite fed on a bed of suitable inert material
with addition of a sorbent material (such as lime stone) is burnt in suspension through the
action of primary air distributed below the combustor floor. In addition, secondary air is
introduced at suitable points in the combustion zone to ensure controlled and complete
combustion of the fuel. Suitable lignite feeding and limestone feeding arrangements are
provided in the typical Circulating Fluidized Bed Combustion systems and is commonly used
as bed material for initial start‐up of the boiler. The steam generators will be designed for
satisfactory continuous operation with the range of lignite/coal expected for this plant
without any need for auxiliary fuel oil for fire stabilization etc. Lignite and Coal are used as
fuel after mixing in appropriate ratio.
Steam generating unit would be provided with electrostatic precipitator in the flue gas
path. The overall efficiency of ESP will be around 99.70% with one field remaining as
operational standby. The ESP would have adequate number of ash hoppers provided with
electric heaters. The design of ESP will be such that the dust burden at the outlet of
chimney with one field out of service doesn’t exceed 150 mg/Nm3 at 100 % BMCR with worst
fuel.
Common chimney for boiler G and H will be constructed. The NOx emission from the steam
generator is least in case of CFBC steam generator design in view of low combustion
temperature maintained in the furnace. The steam generator and auxiliaries will perform
continuously within noise limits as per relevant standard specification but not more than 85
dB (A) at 1.0 meter from any equipment or sub equipment. The steam from the boiler will
go to back pressure turbo generators. The extracted back pressure steam will be used in
process.
4. HYDROGEN PEROXIDE :
MANUFACTURING PROCESS:
This process is based on a circulating working solution, known as the AO (autoxidation)
process for hydrogen peroxide production. The steps, which the working solution passes
through, are hydrogenation, oxidation, drying and regeneration. The working solution
consists of organic solvents and quinones, 2‐ethylanthraquinone and 2‐
ethyltetrahydroanthraquinone and their reduced derivatives. The quinones act as carriers
of hydrogen between the hydrogenation and oxidation steps.
10
Hydrogenation: The working solution and hydrogen are fed to a hydrogenator and in the
presence of catalyst, 2‐ethyltetranthraquinone (H4EAQ or THEAQ) is partially converted to
2‐ethyltetrahydroanthraquinone (H4EAQH2 or THEAQH2) (Reaction‐1). The conversion ration
is primarily controlled by the amount and activity of the catalyst present in the system,
temperature and hydrogen concentration. An excess flow of hydrogen (recycle) to the
hydrogenator is maintained to fluidize the catalyst. The hydrogen is taken out in the reactor
top and returned to the hydrogenator via a recycle compressor. The working solution and
catalyst flow to the primary filters. Here the forward flow of liquid is separated from
catalyst and passes on to an oxidizer feed tank while the remaining working solution and
catalyst are returned to the hydrogenator.
Oxidation: The hydrogenated working solution combined with air (oxygen) in an oxidizer. It
is in this step of the process that hydrogen peroxide (H2O2) is actually produced. The
HEAQH2 in the working solution chemically reacts with oxygen to produce H4EAQ and H2O2
(Reaction 2). Hydrogen peroxide at this point is dissolved in the working solution and the
only visible indication that reaction has taken place is a colour change in the working
solution. The hydrogenated solution is dark brown, during the oxidation the colour changes
and becomes reddish brown.
In the top of the reactor, the inert fraction of the air is separated from the working solution
and discharges through a solvent recovery system. The working solution flows into a
degasser, where any dissolved inert gas is separated from the liquid phase.
11
Extraction: Working solution form the oxidizer degasser is fed into the bottom and
demineralized water into the top of an extraction column. Water is the continuous phase
and working solution the discontinuous phase. Due to the different densities of the two
phases the working solution flows upwards and discharges from the top of the extractor
after being stripped of its hydrogen peroxide. The aqueous phase discharging from the
bottom of the extractor contains normally 30‐35% hydrogen peroxide.
Product Treatment: Hydrogen peroxide is discharged from the bottom of the extractor into
a purification system. The function of the purification system is to remove traces of working
solution components into order to minimize losses and get a low total organic carbon
content of the crude product, which improves the stability.
Drying: The working solution leaving the extractor is saturated with water. The drier
reduces the water content by heating the working solution and flashing it under vacuum.
The benefits with less water in the working solution are better catalyst efficiency and a
lower operating temperature in the hydrogenator, resulting in less side reactions.
Regeneration: Due to the circulating working solution, undesirable compounds (principally
different quinine derivatives) can accumulate in the system. In order to keep the
concentration of the undesirable compounds into active quinones. This is carried out in
columns with activated alumina, the process is known as regeneration. If oxidized working
solution is fed to the alumina beds a reaction known as reversion will occur. The reversion
reaction converts H4EAQ to EAQ, and can be used to control the ration between tetra and
anthra in the working solution.
25
FLOW DIAGRAM:
Hydrogenation
Product Cleaning
Extraction
Solvent recovery
Regeneration
Oxidation Filtration Concentrati
on
Day tanks and Product
storage
Packing &
Loading
H2
Working Solution
Catalyst
Catalyst + Reduced W.S
Inert & H2 Purge
Catalyst + Reduced W.S
Reduced W.S
Air
Ox. W.S
Oxygen Depleted air
Oxygen depleted air to atm
H2O2 30‐33 wt.%
H2O2 30‐33 wt.%
Demineralized water
H3PO4
H2O2 50 wt.%
Stabilizer
Drying Extracted W.S
Oxidized W.S
Spent Alumina
Activated Alumina
H2O2 50 wt.%
Organic return
Oxidized W.S
Water recovery (used as makeup water)
Vapour( water,solvent,inerts)
Activated carbon Spent carbon
26
MATERIAL BALANCE :
5. GLYCERIN & EPICHLOROHYDRINE (ECH) :
The plant is designed to produce Epichlorohydrin from crude glycerin and HCl gas. The
plant consists of
I. Glycerin Purification Plant
II. ECH Production Plant
I. Glycerin Purification Plant
The liquid raw materials like Crude Glycerin, Methanol and NaOH are stored in the
storage tanks. Crude Glycerin and NaOH are pumped from the storage tanks into the
neutralization vessel.
Neutralization and Drying of Crude Glycerin: The Crude‐Glycerin is neutralized in the
Vessel with approx. 30 % concentrated NaOH and preheated up to 120°C. In the first
drying column, the main content of water is evaporated under atmospheric pressure
and in the second drying column, the water content is reduced below 1 wt. % under
H2 – 730 Nm3 Air – 4100 Nm3
Working Solution – 3.1 Kg Catalyst – 0.04 Kg
Phosphoric Acid – 0.3 Kg
Stabilizer – 1.3 Kg DM Water – 2 m3
Activated Alumina – 10 Kg NaOH (100%) – 1 Kg HNO3 (100%) – 1 Kg
Activated carbon – 1.01 Kg
Spent Alumina 10 Kg
Oxygen depleted air to atm 4000 Nm3
Solvent 12.5 g/m3
Spent Carbon 1.01 Kg
Inert & H2 Purge 26 Nm3
Solvent 2 g/m3
H2O2 (50 wt.%) 1.0 MT
Wastewater to ETP 0.714 m3
Inert N2 – 25 Nm3
Catalyst 0.04 Kg
27
Vacuum. In the first drying column, the Methanol content is also removed together
with the water. In the second drying column, the Glycerin content in the vapor is
removed in the partial condenser.
Rectification: After the dryer section, the crude Glycerin comes into the column
bottom and is evaporated in a forced circulation evaporator and rectified in 3 packing
sections. Refined glycerin is taken out from middle packing section. The by‐product is
impure Glycerin collected from top packing section which is recycled into the column
and only in case of bad Crude Glycerin quality approx. 5% of the total produced
Glycerin has to be recycled into the Vessel.
Purification of bottom product: Depending of the salt concentration in the crude
Glycerin, a certain quantity of bottom product has to be pumped into the heavies
separation decanter centrifuge where crude Glycerin stream is recycled to the bottom
of column and another part is fed into the thin film evaporators where the main part
of the Glycerin is separated and the remaining part goes into the lock hopper vessels.
The bottom product consisting of 82 wt % MONG / Glycerin and 18 wt%
heavies/polymers is removed from the lock hopper and sent to disposal pit. After
natural cooling and solidification, product is dispatched outside plant.
Salt purification (not required if crude glycerin is free of salt): The removed salt is
mixed and purified with Methanol before the stream goes into Separator to separate
the salt and into the dryer where the remaining Methanol is removed from the salt.
The purified salt can be used for brine make up while the recovered Methanol goes
into the neutralization Vessel.
Methanol Distillation: The Methanol Water mixture from the top of the dryer column
is purified in the methanol distillation column. The cleaned Methanol will be pumped
back to the Methanol storage tank.
II. ECH Production Plant
The liquid raw materials like refined Glycerin and NaOH are stored in the storage tanks.
HCl gas is delivered by pipeline from the HCl‐synthesis unit with pressure. Oxalic acid is
delivered as a powder in bags.
Glycerin and NaOH are pumped from the storage tanks into the reaction vessels. The
Oxalic acid catalyst is dissolved in water once per day and then continuously pumped in
the Chlorination reactor.
28
Chlorination of Glycerin: The Glycerin is heated in the circulation loop of the storage
tank up to 80°C and is absorbing the excess of HCl Gas in the scrubber, preheated up
to 120°C in heat exchanger and is reacted with the excess of HCl from the Chlorination
reactor.
The main Chlorination step is taking place in the reactor, where on the bottom is the
feed of the preheated Glycerin, the HCl gas and the catalyst oxalic acid together with
the bottom product from the vacuum distillation.
The reaction happens in two steps:
Step one: C3H8O3 + HCl = C3H7ClO2 + H2O
Step two: C3H7ClO2 + HCl = C3H6Cl2O + H2O
Step one is much faster than step two.
Separation of Reaction Products: Dichlorhydrin and Water: The overflows of the
reactor are collected in the vessel and pumped into the vacuum distillation columns
where water and Dichlorhydrin is separated from the Glycerin and Monochlorhydrin as
a bottom product.
Separation of Waste Products A small purge is continuously separated from the
reactor circuit and distilled in the thin film evaporator to separate the Dichlorhydrine &
Monochlorhydrin to reduce the product losses in the waste. The liquid waste stream is
then sent to incinerator.
Saponification into Epichlorohydrin: The saponification works according the reaction:
C3H6Cl2O + NaOH = C3H5ClO + H2O + NaCl
To avoid polymerization as side reaction the NaOH is fed as a 20 wt% solution, which is
prepared inside the plant.
Separation of Epichlorohydrin from Brine: After saponification step, the brine is
treated in the stripper column and nearly azeotropic mixture of water and
Epichlorohydrin is recovered on the top of the stripper. After condensing the vapors,
water rich phase and an Epichlorohydrin‐rich phase is obtained. The water‐rich phase is
recycled into the stripper and the Epichlorohydrin rich phase is the feed for the
Epichlorohydrin purification unit.
Purification of Epichlorohydrin (99.8 wt.%): To obtain high quality Epichlorohydrin a
two column rectification is necessary. In the first column, the water content is
separated and in the second column, the Epichlorohydrin is recovered as a top product
and as bottom product some polymers and equilibrium products are separated.
29
Effluent Brine Stream: Effluent brine from ECH distillation columns shall be sent to the
separate crystallizers/pond for solar evaporation of this stream so as to recover the
salt.
FLOW DIAGRAM :
Epichlorohydrin
Steam
Chlorination
Refined Glycerin
Oxalic Acid
HCl gas
Saponification NaOH
Dichlorohydrin + Water
Stripper Column
Effluent Brine
Water‐rich phase
Recycle
Epichlorohydrin purification unit
Waste Incinerator
Waste gas
Waste gas from glycerin
purification plant
Flue gas to ATM
Purge (Residues)
Glycerin Purification Plant
Crude Glycerin NaOH
Salt
MONG/Glycerin Foot
Methanol +Water
D.M.Water
Recycle
Epichlorohydrin
30
MATERIAL BALANCE :
6. MONO CHLORO ACETIC ACID (MCAA):
Manufacturing Process:
• Mono Chloro Acetic Acid (MCAA) is produced by continuous chlorination of acetic
acid in presence of catalyst. After reaction is over, the Crude MCAA is fed to the
crystallizers where it is cooled. The slurry containing crude MCAA crystals is fed to
the pusher centrifuge continuously. Pusher Centrifuge continuously separates ML
and MCAA powder. Powder is packed using auto filling system.
• Gases containing HCl & Chlorine is passed through the scrubbers wherein these
are scrubbed with water and caustic soda solution respectively to get 32% HCl
solution and Hypo.
• Mother liquor from the centrifuge is collected separately and taken for further
chlorination to get second crop of Mono Chloro acetic acid. The MCAA powder
collected from centrifuge is packed in HDPE 50 kg capacity bags. The MCAA
powder is white free flowing needle crystal and hygroscopic in nature.
Crude Glycerin – 8.2 Ton
Oxalic Acid – 4 Kg
NaOH (100 wt. %) – 4.46 Ton
ECH – 6.25 Ton
Cl2 gas – 7.2 Ton
H2 gas – 0.30 Ton
Salt 0.4 Ton
Glycerin
Foot/MONG 0.6 Ton
DM Water – 14 m3
32 wt.% HCl 1.4 Ton
Brine 20 m3
Waste gas & Purge (Residues)
To Waste Incinerator 0.34 Ton
Refined Glycerin – 6.6 Ton to ECH Plant
Waste water from GPP 4.1 m3
Waste gas to Incinerator 0.6 Ton
Methanol/Water
0.08 Ton
31
Chemical Reaction:
CH3COOH + Cl2 ‐‐‐‐‐‐‐‐‐‐‐> ClCH2COOH + HCl
FLOW DIAGRAM:
Acetic Acid
Chlorine Monochloro acetic Acid
Hydrochloric Acid
Continuous Chlorination
Acidic Scrubber
Batch Reactor Crystalizer
Filtration
Filtration
Hydrogenation
Alkali Scrubber
Filtration
Crystalizer
Acetic Acid
Chlorine Gas SMC/Acetic Anhydride
Catalyst
HCL+Cl2 gas
HCL+Cl2 gas
Water
32% HCL solution
Crude MCAA
MCAA Slurry
MCAA Powder for Packing
ML for processing
Chlorine gas
Chlorine gas
Dilute Caustic
Hypo
Crude MCAA
MCAA Slurry
MCAA Powder for Packing
ML
Catalyst
Hydrogen
Unreacted Hydrogen
MCAA + Catalyst Slurry
MCAA powder Wet catalyst
ML
32
MATERIAL BALANCE: 7. TRI CHLORO ACETYL CHLORIDE:
Manufacturing Process:
• ML collected from centrifuge is having 50% MCAA and 50% DCAA (Di Chloro Acetic
Acid). It is charged to the hydrogenation reactor in batch mode. DCAA is converted
back to MCAA and is filtered to get the additional crop of MCAA crystals. The ML
coming out after this process is taken to another reactor where it is reacted with
chlorine gas in presence of catalysts. Chloro Acetyl Chloride (CAC) and Di Chloro
Acetyl Chloride (DCAC) are in crude form and are distilled and pure mixture of CAC
and DCAC is collected. It is further reacted with pyridine at high temp. Tri Chloro
Acetyl Chloride (TCAC) is produced in crude form. It is distilled and purified to get
99.5% TCAC liquid.
• Final discharge of ML contains 50% MCAA and 50% DCAA. It is collected separately. It
is a by‐product in the process.
• HCl and unreacted chlorine gases from reactors are taken to the water and alkali
scrubbers respectively. Here we get 32% HCl solution and Hypo 15% solution as by
products.
• Gases from the reacted are scrubbed in soda ash tower, water scrubbers and dilute
caustic scrubbers. Sodium bi sulfite dilute solution, 32% HCl solution and dilute hypo
Chlorine Gas – 100 Ton
Acetic acid – 79 Ton MCAA powder – 120 Ton
Acetic Anhydride/SMC – 4 Ton
Hydrogen gas – 0.72 Ton
Catalyst – 0.15 Ton
Dilute caustic soda – 53.7 Ton
32% HCl Solution 147.72 Ton
Hypo 62.027 Ton
Unreacted Hydrogen 0.36 Ton
Water – 102.94 Ton
ML 10.213 Ton
Wet catalyst 0.19 Ton
33
solution we received as by‐products. Final vent is from caustic ventury in which free
chlorine gas will be 30 to 40 ppm.
• There is no air emission and no liquid pollution. It is a completely closed system
there is no environmental pollutions from the system.
Chemical Reaction:
4CH3COOH + 15Cl2 + S2Cl2 ‐‐‐‐‐‐‐‐‐‐> 4CCl3COCl + 16HCl + SO2
•
FLOW DIAGRAM:
Liquid Chlorine
Tri Chloro Acetyl Chloride
Acetic Acid Hydrochloric Acid
Sulphur mono Chloride Sulphur
Dioxide
Distillation
Acid Scrubber
Water Scrubber
Distillation
Chlorination
Alkali Scrubber
ML Water + Unreacted Acetic
Acid
Distilled ML
Chlorine
SMC + catalyst
Crude TCAC
Fore cut/Inter
cut/End cut
TCAC TAR
Chlorine + HCl + SO2
Dilute soda solution
Dilute NaHSO3 solution
Chlorine + HCl
Water
32% HCl Solution
Chlorine
Dilute Hypo Solution
Dilute Caustic Solution
34
MATERIAL BALANCE:
ML – 10.213 Ton
Chlorine – 16.025 Ton TCAC – 8.8 Ton
SMC + Catalyst – 3.35 Ton
Dilute Soda solution – 10.166 Ton
Dilute Caustic Solution – 5.471 Ton
Water – 19 Ton
Fore cut/Inter cut/End cut – 3.98
Ton
TAR 1.52 Ton
Water + Unreacted Acetic Acid – 3.162 Ton
32 % HCl Solution 27.23 Ton
Dilute Hypo Solution 6.928 Ton
Dilute NaHSO3 Solution
12.605 Ton
35
ANNEXURE‐III DETAILS OF WATER CONSUMPTION
Sr. No.
Source Water Consumption (m3/day) Existing Proposed Total
Soda Ash Plant 1. Domestic 220 100 320 2. Process 22160 8863 31023 3. Boiler 4800 ‐‐‐ 4800 4. Cooling 338265 135306 473571 5. Others 1020 450 1470
Total (I) 366465 144719 511184 Toilet soap plant
1. Domestic 60 0 60 2. Process 150 0 150 3. Washing 25 0 25 4. Cooling 325 0 325
Total (II) 560 0 560 Caustic Soda Plant & Captive Power Plant
1. Domestic 10 5.5 15.5 2. Process 4904 2754 7658 3. Boiler 3140 4500 7640 4. Cooling 28262 15897 44159
Total (III) 36316 23157 59473 Salt works
1. Salt works 526951 279000 805951 Total (IV) 526951 279000 805951
Bromine Plant 1. Process 11000 0 11000 2. Cooling 1000 0 1000
Total (V) 12000 0 12000 Chlorine & Hydrogen Derivatives
1. Domestic 0 10.1 10.1 2. Process + DM 0 1116 1116 3. Cooling + Chilling 0 7568 7568 4. Boiler 0 0 0 5. Washing/Others 0 101 101
Total (VI) 0 8795.1 8795.1 Grand Total (I to VI) 942292 455671 1397963
36
DETAILS OF WASTEWATER GENERATION
Sr. No.
Source Wastewater Generation (m3/day) Existing Proposed Total
Soda Ash plant 1. Domestic 150 34 184 2. Process 23248 9299 32547 3. Boiler 216 0 216 4. Cooling 338265 135306 473571 5. Others 0 0 0
Total 361879 144369 506518 Toilet Soap plant
1. Domestic 48 0 48 2. Process 0 0 0 3. Washing 25 0 25 4. Cooling 275 0 275
Total 348 0 348 Caustic Soda Plant & CPP
1. Domestic 7 4 11 2. Process 480 270 750 3. Boiler 365 975 1340 4. Cooling 28742 15100 43842
Total 29594 16349 45943 Salt works
1. Salt works 8500 2500 11000 Total 8500 2500 11000
Bromine plant 1. Cooling tower 1000 0 1000 2. Process 12500 0 12500
Total 13500 0 13500 Chlorine & Hydrogen Derivatives 1. Domestic 0 6.6 6.6 2. Process + DM 0 695 695 3. Cooling +
Chilling 0 2977 2977
4. Boiler 0 0 0 5. Washing/Others 0 41 41
Total (VI) 0 3719.6 3719.6 Grand Total (I to VI) 413821 167207.6 581029
37
ANNEXURE‐III WASTEWATER TREATMENT PROCESS
1. Soda Ash Plant Effluent Treatment System:
The effluent from the Soda Ash plant mainly consists of suspended solids. The effluent is
pumped into the Primary Settling Ponds through pipelines. The Settling Ponds having
trapezoidal settling facility where the effluent is retained for settling of solids. The
overflow of the Primary Settling Ponds is taken into one of the two large impervious
Clear Liquor Collection Ponds. The Clear liquor from the Clear liquor pond is utilized in the
existing Salt works to recover additional Salt and Gypsum.
Settler Tank
(200 acres)
Clear Liquor Tank
(100 acres)
Sump
Utilization in Existing Salt Works for Recovery of Salt
& Gypsum
Effluent from Soda Ash Plant
38
2. Caustic Soda Plant Effluent Treatment System:
The process effluents and floor washing from the caustic soda & Captive Power plant
needs pH correction. The two streams are pumped to neutralization tank through
pipelines and treated with HCl/NaOH to ensure complete neutralization. The neutralized
effluent is settled and the supernatant is sent to Salt work. The blow downs from the
cooling towers of caustic soda plant from both the once through cooling system, and
fresh water cooling towers are sent to salt works. Cooling water from caustic soda plant,
captive power plant (once through cooling water) and boiler are sent to salt works.
ETP – 1 (Existing)
ETP – 2 (Proposed)
Neutralization Tank (2 Nos.)
10 m X 5 m X 2m
Treated Water Tank
(1 Nos.) 10 m X 5 m X 2m
Treated Effluent used for Green belt development
Or Dust Suppression purpose
Floor Washings
Process Effluent
Neutralization Tank
Treated Water
Tank
Treated Effluent used for Green belt development
Or Dust Suppression purpose
Floor Washings
Process Effluent
39
3. H2O2 Plant Effluent Treatment System:
Process Effluent Treatment Scheme
From Process plant
Process Effluent
10% NaOH
1
2
3
5
4 Compartment I
Compartment II
6 Treated Effluent
To Utility ETP
Equipment Description:
1 10% NaOH Dosing Tank 2 10% NaOH Dosing Pump 3 10% NaOH Dosing Pump 4 Neutralization Reactor 5 Agitator 6 Treated Effluent Transfer
Pump
40
Utility Effluent Treatment Scheme
Alum
1
NaOCL
3
2
4
Utility Effluent
Treated Effluent
From Utility Area
From Process ETP
5
6 7
8
11
10
9
Treated Effluent
To RO Treatment
Equipment Description: 1 Alum dosing Tank 2 Alum dosing pump 3 NaOCL Dosing Tank 4 NaOCL Dosing Pump 5 Effluent Transfer Pump 6 Utility Effluent Pit 7 pH Adjustment Pit 8 Transfer Pump 9 Filtered Water Transfer Pump 10 Filtered Water Pit 11 Sand Filter
41
1. MCAA & TCAC PLANT EFFLUENT TREATMENT SYSTEM:
Process Description of the Effluent Treatment Plant
EFFLUENT COLLECTION AND EQUALIZATION:
All the effluent streams coming from plant and utilities are collected in a collection sump.
Where it is directed to ETP as per the hydraulic flow diagram mentioned on the attached
drawing for further treatment.
PRIMARY TREATMENT:
All the equalized effluent taken for neutralization tank. Where hydrated lime will be used
as neutralizing agent. Than it is to be pumped in a batch wise manner to flash mixture
where organic matter is remove by coagulation, flocculation and precipitation with the
help of Ferric Alum/ Ploy aluminum Chloride/Lime and polyelectrolyte. After completion
of precipitation, treated effluent is passed through primary clarifier to separate out solid
sludge. Clear effluent from primary clarifier is allowed to overflow in bioreactor for
secondary biological treatment. Sludge from the bottom of primary clarifier is taken into
sludge sump. Filter press will be used as dewatering equipment. Effluent emerging out
from primary treatment will be reduced COD and TDS as organic dissolved solids also get
precipitated out.
SECONDARY TREATMENT /AERATION
For secondary biological treatment, Industry will be provided aeration tank having three
partitions having volumetric capacity of 600 KL each so total volume of aeration tank will
be 1800 kl with 24 hrs retention time to considering 50% recycle of sludge water. For
desired reduction of COD and BOD, the suitable bacterial culture will be nourished and
desired level of MLSS and MLVSS will always be maintained in the aerator by adding cow
dung or other nutrients like Urea/DAP as and when required. For providing required
amount of air for biological degradation, twin lob blower of 25 HP x 3 will be provided.
Such large bio‐reactor will ensure long residence time and result into desired COD
reduction in bioreactor on the daily basis.
The overflow of aeration tank will be directed to final clarifier having mechanical
scrapper to efficient sludge settling. The settled sludge will be taken to sludge sump
from where it will be fed to above referred filter press for further compaction. Clear
treated effluent from final clarifier will overflow to final treated effluent collection well
from where after due analysis treated effluent will be reuse in gardening/plantation with
in plant premises.
42
1 2 3
4 5 6
4 4
7
8 9
11 10
12
UNIT OF EFFLUENT TREATMENT PLANT
Sr. No. Description
1 Oil & Grease Trap
2 Collection Tank
3 Neutralization Tank
4 Chemical Dosing Tank
5 Flash Mixer
6 Flocculation Chamber
7 Primary Clarifier
8 Aeration Tank
9 Secondary Clarifier
10 Filter press
(Dewatering Unit)
11 Sludge Sump
12 Treated Effluent Sump
43
ANNEXURE‐IV
DETAILS OF SOLID WASTE AND HAZARDOUS WASTE
SOLID WASTE GENERATION AND DISPOSAL:
Sr. No.
Solid Waste Quantity (TPD) Mode of Disposal
Existing Proposed After Expansion
1 Settling Pond Sludge
740 140 900 Shall be used in road construction, salt works bund preparation
2 Lime stone rejects /under size
460 240 700 Shall be used in boilers for desulphurization in boilers
3 Brine Sludge 11.6 7.4 19 Nonhazardous; Shall be used dumped in identified area
4 Fly ash/ Bottom ash
1455 730 2185 Brick manufacturing, bund preparation, road making etc…
5 Incineration Ash ‐‐‐ 15 15 Brick manufacturing, bund preparation, road making etc…
HAZARDOUS WASTE GENERATION & DISPOSAL
Sr. No.
Hazardous Waste
Category Quantity (MTPA) Mode of Disposal
Existing Proposed Total After Expansion
1 Soda Ash Plant Waste Oil/ Lub. Oil from
5.1 5.5 4.5 10.0 Collection, Storage, Transportation & disposal by selling to Registered Recyclers
Spent ion exchange resins
34.2 5700 L cation & 12600 L anion (once in 10 years)
Collection, Storage, Transportation, Disposal by selling to authorized recyclers or sent to NECL Nandesari for Incineration.
Discarded bags/drums/containers etc…
33.3 2 0.5 2.5 Collection, Storage, Transportation, Disposal by selling to authorized recyclers
44
2. Caustic Soda Plant
Waste Oil/ Lub. Oil from
5.1 20 10 30 Collection, Storage, Transportation & disposal by selling to Registered Recyclers
Spent ion exchange resins
34.2 1.56 1.0 2.56 Collection, Storage, Transportation, Disposal by selling to authorized recyclers or sent to NECL Nandesari for Incineration.
Residue/ Sludge & Filter sludge
16.2 4176 2350 6526 Collection, Storage, Transportation, Disposal at TSDF
ETP sludge 34.3 96 54 150 Collection, Storage, Transportation, Disposal at TSDF
Spent Sulphuric Acid (80%)
D2 4320 2200 6520 Collection, Storage, Transportation, reuse as raw material for Nirma Ltd. Moraiya and other end users.
3. Toilet Soap Plant
Waste Oil/ Lub. Oil from
5.1 0.45 0 0.45 Collection, Storage, Transportation & disposal by selling to Registered Recyclers
ETP sludge 34.3 48 0 48 Collection, Storage, Transportation, Disposal at TSDF
Glycerin foot D6‐II 72 0 72 Collection, Storage, Transportation & disposal by selling to M/s. Ultratech Cement for Co‐ incineration in cement kiln/NECL for Incineration.
Spent Sulphuric Acid (80%)
D2 24000 0 24000 Collection, Storage, Transportation, reuse as raw material for Nirma Ltd. Moraiya and other end users.
45
4 Chlorine & Hydrogen Derivatives
Waste Oil/ Lub. Oil
5.1 0 10 10 Collection, Storage, Transportation & disposal by selling to Registered Recyclers
Discarded containers/ Barrels/empty drums/empty bags
33.3 0 10 10 Collection, Storage and disposal by selling to authorized recyclers.
ETP sludge 34.3 0 120 120
Collection, Storage, Transportation, Disposal at TSDF
Glycerin foot D6‐II 0 5356
5356 Collection, Storage & incineration in plant incinerator.
Catalyst from regeneration
35.2 0
1.2 1.2 Collection, Storage, Transportation, Disposal at Common Haz. Waste incineration facility
Spent Carbon from solvent recovery
35.3 0 3.0 3.0 Collection, Storage, Transportation, Disposal at Common Haz. Waste incineration facility
Spent Carbon from ETP
34.3 0 3.0 3.0 Collection, Storage, Transportation, Disposal at TSDF
Distillation Residue
36.4 0.0 550 550 Collection, Storage, Transportation, Disposal at Common Haz. Waste incineration facility
46
ANNEXURE‐V
DETAILS OF STACKS AND PROCESS VENTS
DETAILS OF STACK EMISSIONS
Sr.
No.
Stack Attached to Stack Height
(m)
Stack
Dia. (m)
Air Pollution
Control System
Pollutant
1 Soda Ash Plant
Boiler A, B, C & D
(100 TPH each)
100
(Common
stack)
5.04 ESP to Each boilers PM
SO2
NOx
DG Sets (2 nos.) 24 (each) 0.2 ‐‐‐
2 Caustic Soda & CPP
Boiler E & F (200
TPH each)
121
(Common
Stack)
4.5 ESP PM
SO2
NOx
Boiler G & H (350
TPH + 350 TPH
standby)
(Proposed)
121
(Common
Stack)
4.5 ESP PM
SO2
NOx
DG Set (1000 KVA) 30 0.32 ‐‐‐ PM
SO2
NOx
DG Set (1500 KVA)
Proposed
30 0.32 ‐‐‐
DG Set (1500 KVA)
Proposed
30 0.32 ‐‐‐
3 Toilet Soap
Thermic Fluid
Heater
45 0.4 ‐‐‐ PM
SO2
NOx
47
DETAILS OF PROCESS EMISSIONS
Sr.
No.
Vent Attached to Stack
Height (m)
Stack
Dia. (m)
Air Pollution
Control System
Pollutant
1 Soda Ash Plant
Lime Kilns (A to F) – 6
nos.
68
(Common
Stack)
0.8 3 scrubbers and
two ESP in Series
PM, SO2, NOx
Ammonia Recovery
System
56
(Common
Stack)
0.75 Brine Scrubbers
(3 nos.)
Ammonia
Lime Grinding System
(3 nos.)
60 0.65 Bag Filter PM
Calcinations Vessel
(2 nos.)
29 each 0.7 Water Scrubber PM
Densification 1 40 1.37 Water Scrubber PM
Densification 2 51 1.37 Water Scrubber PM
Lime Kilns (G & H) – 2
nos. (Proposed)
68
(Common
Stack)
0.8 One scrubbers and
one ESP in Series
PM, SO2, NOx
Ammonia Recovery
System (D & E) 2 nos.
(Proposed)
56
(Common
Stack)
0.75 Brine Scrubbers
(2 nos.)
Ammonia
Lime Grinding System
(2 nos.) (Proposed)
60 0.65 Bag Filter PM
Calcinations Vessel
(2 nos.) (Proposed)
29
(Common
vent)
0.7 Water Scrubber PM
Densification 3
(Proposed)
51 1.37 Water Scrubber PM
48
2 Caustic Soda and CPP
HCl Synthesis Unit ‐ 1 30 0.1 Water Scrubbers HCl & Cl2
HCl Synthesis Unit ‐ 2 30 0.1 Water Scrubbers HCl & Cl2
Waste Gas Dechlorination System ‐ 1
30 0.3 18% NaOH
Scrubber
Cl2
Waste Gas
Dechlorination
System ‐ 2
30 0.3 18% NaOH
Scrubber
Cl2
HCl Synthesis Unit – 3
(Proposed)
30 0.1 Water Scrubbers HCl & Cl2
HCl Synthesis Unit – 4
(Proposed)
30 0.1 Water Scrubbers HCl & Cl2
Waste Gas
Dechlorination
System‐ 3 (Proposed)
30 0.3 18% NaOH
Scrubber
Cl2
3. Bromine Plant
Debromination System
30 0.3 Alkali Scrubber Bromine
4. Chlorine & Hydrogen Derivatives
Solvent Recovery
(Proposed)
30 0.3 Ceramic +
Activated Carbon
Filter
Aromatic Solvent
Hydrogenation Plant
(purge gas)
(Proposed)
30 0.3 Ceramic +
Activated Carbon
Filter
H2 + Aromatic
Solvent
Incinerator & its
scrubber (Proposed)
30 0.3 Water Scrubber PM, SO2, CO,
NOx, HCl, TOC
HCl Synthesis Unit
(Proposed)
30 0.1 Water Scrubbers HCl
Chlorination Plant
(Proposed)
30 0.3 Acidic/Water
Scrubber (3 nos.)
SO2, HCl, Cl2
Chlorination Plant 30 0.3 Alkali Scrubber Cl2
49
(Proposed) (3 nos.)
Chlorination
(Proposed)
30 0.3 Water Scrubber SO2, HCl, Cl2
Hydrogenation Plant
(purge gas)
(Proposed)
30 0.3 ‐‐‐‐ H2
50
Annexure‐VI
Noise level, at existing plant
Sr. No. Location Noise level in dB(A)
1 Near Security Main Gate No.1 60.3
2 Near Guest House 56.1
3 Near Security Gate No. 2 58.1
4 Near Safety office 57.2
5 Near Canteen 58.9
6 Near Laboratory 63.5
7 Near Work Shop area 70.2
8 Toilet soap packing area 63.7
9 Near Toilet soap ETP 60.1
10 Near CCR Electrical 76.4
11 Near DG Room 72.9
12 Near Boiler operator office 82.5
13 Near Boiler Stack area 74.1
14 PWP Station area 73.8
15 Calcination and Filtration Area 74.0
16 Near Brine Purification 73.5
17 Grinding mill area 77.6
18 Lime kiln area 75.3
19 Near Bricks Manufacturing area 74.8
20 Near RO Plant area 70.6
21 Near Thermic Fluid Heater 71.4
22 Near Salt works office 66.3
23 Near Diesel Pumping station 64.8