Chemical industry is one of India’s oldest industries, contributing significantly towards the industrial and economic growth of the nation. The Indian Chemical Industry forms the backbone of the industrial and agricultural development of India and provides building blocks for several downstream industries. Exports of chemicals from India have increased significantly and account for about 14% of total exports and 9% of total imports of the country. The Indian chemical industry comprises both small and large-scale units. Fiscal concessions granted to the small sector in the mid-eighties led to the establishment of a large number of units in the Small Scale Industries (SSI) sector. Against an overall installed capacity of around 10 mn tonnes, India produces nearly 8 mn tonne, of an assortment of chemicals. These exclude petrochemicals, but include chlor-alkalis, and dyes and dyestuffs. The chemicals industry is a highly versatile segment in the overall industrial economy of India. It has linkages with almost every other industrial activity, be it food processing, metallurgy, textiles, rubber or leather. There is, in fact, hardly any segment where chemicals do not feature. The major sub segments of this industry include alkali, organic chemicals, inorganic chemicals, pesticides, dyes & dyestuffs and specialty chemicals. The Indian chemical industry deals in products like fertilizers, bromine compounds, catalyst, sodium and sodium compounds, dye intermediates, inks and resins, phosphorous, paint chemicals, coatings, isobutyl, zinc sulphate, zinc chloride, water treatment chemicals, organic surfactants, pigment dispersions, industrial aerosols and many more.
The size of the Indian chemicals industry was estimated to be around USD 83 billion. It contributes around 5% to India’s total GDP. The chemical industry also accounts for 13% share in total exports and 8% share in total imports of India. The sector contributes around 20% to national revenue by way of taxes and levies. In terms of sub-sectors, the Indian chemicals industry is composed of base chemicals that account for 53% share, pharmaceuticals contributing 24%, specialty chemicals 18%, biotech 3% and agro chemicals 2% share. The Indian chemicals industry has huge growth potential for the future. The industry has remained among the fastest growing sectors of the economy. The chemical industry remains concentrated in the western region, which claims a near 50% share of investment flows. In the western region, Gujarat makes the largest contribution to the chemical industry’s production activity.
The content of the book includes information about chemical industry. the major contents of this book are project profiles of projects like copper sulphate from metallic scrap copper, hydrogen peroxide (anthraquinone autoxidation process), sodium chlorite (naclo2), zinc oxide (from zinc dross), poly aluminium chloride (PAC), calcium propionate, ethylene oxide, antimony potassium tartrate, humic acid from lignite coal.
Project profile contains information like introduction, properties, uses and applications, process, process flow diagram, plant economics, land and building, plant and machinery, fixed capital, working capital requirement/month, total working capital/month, cost of project, total capital investment, turn over/annum, profit sales ratio, rate of return, breakeven point (B.E.P)
This book is very useful for new entrepreneurs, technical institutions, existing units and technocrats.
Copper Sulphate from
Metallic Scrap Copper
discovery of copper goes back to prehistoric times and has been mined
than 6000 years. Gold was probably the first metal to attract man's
because of its sparkling yellow color. Iron, in the form of meteorites,
the other hand, have been used before copper in some localities.
there is evidence that every ancient metal culture was actually
the use of the red metal. The early age of copper, so the word goes,
greatest development in Egypt. The most important copper-ore deposits
Antiquity were in Sinai, Syria, Afghanistan, Cyprus, Iberia and Central
European copper mines of the Bronze Age are known in Austria, Germany,
Spain, Portugal, Greece and Tyrol.
annual consumption of copper is more than nine times as large. The
of copper throughout the world has doubled since the 1970’s to reach
million tons in 2005, of which 70% was produced by mining and 30% by
Up until recent years most of the
discarded electrical and electronic equipment were generally crushed
filled. Land filling with electronic waste (e-waste) can cause serious
to the environment due to the hazardous products contained in waste
and electronic equipment, WEEEs. This aims to prevent the generation of
electrical and electronic waste and to promote re-use, recycling and
forms of recovery in order to reduce the quantity of the discarded
the other hand the amount of precious metals, such as copper and gold
exist in the scrap could be a potential source for new raw material.
the recycling of this type of scrap is still quite limited due to the
heterogeneity of the materials present in the waste and the complexity
producing new equipment.
The methods applied in metal
from electronically waste are based on mechanical, pyrometallurgical or
hydrometallurgical processes. The mechanical or physical processes have
utilized commercially in the recycling industry. The drawback with
processes is air pollution and high energy consumption.
According to Jin et. al
hydrometallurgical methods are more exact, more predictable and more
controlled than pyro metallurgical processing for metal recovery from
Hydrometallurgical processes are
based on the dissolution of the metals in the raw material into, e.g.
alkaline solutions. A hydrometallurgical process has a generally lower
than a mechanical or a pyrometallurgical process and can be
operated even on a small scale. Thus, this technique has been widely
recover metals from other industrial wastes, due to its flexible,
operation and energy-saving features.
Copper is one of the most
materials used in the production of electronic equipment and found in
appliances as, e.g. circuit boards. Copper recycling has lately become
important due to the depletion of the earth copper resources and thus
increased price for raw material. The development of recycling
processes is an
important issue to effectively utilize the copper resources, minimize
adverse effects of hazardous materials and protect our environment.
The processes used for copper
recycling depend on the copper content in the raw material, its size
distribution, and other constituents. Three general types can be
Type 1: Copper scrap, used for
refining or direct melting for products. This scrap accounts for about
95 % of
all recycled copper. The value of the recycled copper is generally
its treatment costs.
Type 2: Copper-containing special
as cables, electronic components or printed circuit boards.
necessary before melting the copper. The value of the recycled copper
generally in the range of the overall treatment cost.
Type 3: Copper-containing residues,
example sludges from metal-plating industry. The copper content on
is low. The value of the recycled copper is generally lower than the
cost of the material.
Different methods have been studied
for copper recovery. Some of the hydrometallurgical techniques use
AND CHEMICAL PROPERTIES
Copper (II) Sulphate
Anhydrous Copper Sulphate is
water, slightly soluble in methanol but insoluble in ethanol.
It readily dissolves in aqueous
excess alkali metal cyanides, with the formation of complexes.
The material is hygroscopic, with
into pent hydrate copper sulphate in moist air below 30 deg C.
9,7 h Pa at 25°C
3,603 g/mL at
(II) Sulphate Pent-hydrate
Copper(II) sulfate penta-hydrate
before melting at 150°C (302°F), losing two water molecules at 63°C
followed by two more at 109°C (228°F) and the final water molecule at
proceeds by decomposition of the tetra aqua copper (2+) moiety, two
aqua groups are lost to give a di-aqua copper (2+) moiety. The second
dehydration step occurs with the final two aqua groups are lost.
dehydration occurs when the only unbound water molecule is lost.
At 650°C (1,202°F), copper (II)
decomposes into copper (II) oxide (CuO) and sulfur trioxide (SO3).
Its blue color is due to water of
When heated in an open flame the crystals are dehydrated and turn
Copper sulfate reacts with
hydrochloric acid very strongly. In the reaction the blue solution of
(II) turns green, due to the formation of tetra chloro-cuprate (II):
+ 4 Cl– → CuCl2−4
also reacts with more reactive metals than copper (e.g. Mg, Fe, Zn, Al,
+ Zn → ZnSO4 +Cu
+ Fe → FeSO4 + Cu
+ Mg → MgSO4 + Cu
+ Sn → SnSO4 + Cu
+ 2 Al → Al2(SO4)3
+ 3 Cu
metals more reactive than others like magnesium and aluminium will
secondary reaction. They will form hydroxides with the water while
some hydrogen gas. The copper formed is deposited on the surface of the
metal. The reaction stops when no free surface of the metal is present
USES & APPLICATIONS
sulphate, blue stone, blue vitriol are all common names for pent
cupric sulphate, Cu S04 5 H20,
which is the best known
and the most widely used of the copper salts. Indeed it is often the
raw material for the production of many of the other copper salts.
Today in the
world there are more than 100 manufacturers and the world's consumption
around 200,000 tons per annum of which it is estimated that
three-quarters are used in agriculture, principally as a fungicide.
In the production of copper sulphate virgin copper is seldom, if ever,
the starting raw material. Copper ores are used in countries where
these are mined.
For the bulk of the world's production nonferrous scrap is the general
The scrap is refined and the molten metal poured into water to produce
spherical porous pieces about the size of marbles which are termed
"shot". This shot is dissolved in dilute sulphuric acid in the
presence of air to produce a hot saturated liquor which, if the
large crystals of copper sulphate are required, is allowed to cool
large cooling vats into which strips of lead are hung to provide a
the crystals to grow on. If the granulated (snow) crystal grades are
the cooling process is accelerated by agitating the liquor in water
polymeric coat on the copper scraps was initially removed using some
of industrial grade of sulphuric acid, which can later be washed off to
the pure copper metal scraps. The copper metal scraps were digested at
temperature with constant stirring using concentrated sulphuric acid.
digestion, the copper sulphate was extracted with a lot of distilled
later filtered to remove all unwanted and undigested wastes in the
filtered blue solution of copper sulphate was later concentrated to
formation of hydrated copper sulphate. The crystals were later
in distilled water to obtain a purer form of the salt. The crystals
dried and packaged.
METHODS OF OPERATION
process relates to a method and apparatus for the recycling of scrap
such as the recycling of copper scrap material.
certain operations where useful byproducts are formed, these byproducts
subjected to pressure leaching in order to produce saleable products.
example, in a lead smelting operation for the recovery of lead, copper
is obtained as a byproduct. In order to increase the commercial
the process, the copper matte is further treated in a pressure leaching
in an autoclave to convert the copper matte to copper sulphate, which,
example, is useful as an animal feed supplement.
is also an object of the present method to provide a process and
the recycling of a scrap material for the production of a useful
1 is a flow diagram illustrating the method according to the method;
2 is a schematically side view of an apparatus for use in the method.
to FIG. 1, copper matte from a lead smelter is treated in a continuous
leaching process in a pressure vessel or autoclave 10 to convert the
sulphide in the matte to soluble copper sulphate.
pressure leaching stage is in effect a pressure oxidation and it is
in the presence of oxygen using sulphuric acid.
The matter contains several
such as copper sulphide (Cu2 S), copper arsenide
As), lead sulphide (PbS) and elemental lead as bullion.
The following reactions take place
the autoclave 10:
SO4 +5/2O2 ➝2CuSO4 +H2
O PAC PbS+2O2
The matter is screened as it is fed
to a ball mill 12 for grinding, first at one inch and then 6 mesh. The
materials are crushed and then returned for rescreening. Eventually the
bullion particles greater than 6 mesh are returned to the lead smelter
The ball mill 12 grinds the matte
The matter is stored in a stock
14 in the form of slurry at 75% solids, from where it is fed to the
In addition to the copper matte
slurry, scrap copper wire is introduced into the autoclave 10 to be
with the copper matte. An aspect which renders the process feasible is
introduction of the scrap material to the autoclave separately from the
The copper wire is fed to the
autoclave 10 using a feeding apparatus 16, which is shown in more
FIG. 2. The feeding apparatus 16 overcomes the pressure difference
autoclave pressure and atmospheric pressure, so that the copper wire
can be fed
to the autoclave 10 without interrupting the leaching operation.
The feeding apparatus 16 comprises
hopper 18 leading into a pressurization chamber 20 which in turn leads
autoclave 10 via a safety valve, in the form of a ball valve 22.
A first rotating disc valve 24 is
operative between the hopper 18 and the chamber 20 and a second
valve 26 is operative between the chamber 20 and the autoclave 10. The
24 and 26 have self cleaning faces.
A feeder in the form of a conveyor
belt 28 is provided for feeding scrap copper wire to the hopper 18.
In operation, copper wire is
introduced into the chamber 20 by opening the valve 24 while the valve
closed. Once the chamber 20 is charged with copper wire, the valve 24
and the chamber 20 is pressurized by the introduction of gas under
indicated by the arrow 30, in order to increase pressure in the chamber
above that of the autoclave 10.
The autoclave 10 is then charged
copper wire by opening the valve 26 while the valve 24 remains closed.
cycle is then repeated for a next batch of copper wire.
In this way the autoclave 10 is
charged without interrupting the pressure leach in the autoclave 10.
A solution flush, as indicated by
arrow 32, is used at one or more locations to sweep the system clean
Prior to opening the valve 24 for
next charge, the chamber 20 is depressurized, as indicated by the arrow
the gas content of the chamber 20 is passed to a scrubber.
During the pressure leach in the
autoclave 10, the matter and the copper wire react with the acid at
under 1380 kPa gauge pressure of oxygen. The copper is leached into
and the lead remains in the residue as lead sulphate. Additional acid
introduced into the autoclave 10 to ensure the complete dissolution of
copper wire according to the equation:
+1/2O2 ➝Cu+2 +H2
The slurry discharged from the
autoclave 10 is fed to a letdown and filter feed tank 35. Sulphuric
effecting the leaching operation is fed to the autoclave 10 from a
36, which also contains water and mother liquor which is recycled from
crystallizer in which the copper sulphate is crystallized. The
water and mother liquor are mixed in the recycle tank 36 in suitable
proportions for optimum leaching of copper in the autoclave 10.
When feeding the autoclave 10, the
matte and mother liquor are sampled regularly to determine the Pb, Cu, H2
SO4 and as content. These assays are used to
calculate the acid flow
to and the total flow from the recycle tank 36. Normal target levels
solution discharging from the autoclave 10 are 180 g/l Cu and 15 g/l H2
The autoclave discharge slurry is
kept hot to prevent crystallization of the copper sulphate in the
tank 35. The slurry is then filtered through a filter press 40 to
copper sulphate solution from the lead sulphate cake. The cake is
discharged from the filter 40 into a lugger box for return to the
recover the lead and silver values. The filtrate is passed to a feed
From the feed tank 42, the copper sulphate solution is fed continuously
crystallizer section for the production of copper sulphate.
PROCESS FLOW DIAGRAM
SULPHATE FROM METALLIC SCRAP
of working days
& BUILDING COST
Autoclave Cap. 20 Ton
Tanks for Sulphuric Acid
& Process Control Equipment
Machine like valves, motors, pipeline & fittings etc.
Erection & Installation
LAND & BUILDING
ETP & Other Chemicals
WORKING CAPITAL FOR 3 MONTHS