Physico-Chemical Processes for Wastewater Treatment

Professor V. C. Srivastava
Department of Chemical Engineering
Indian Institute of Technology, Roorkee
Lecture 02
Environmental Acts and Standards

Good day everyone, and welcome to this second lecture of the course on Physico-chemical
processes for wastewater treatment. And today we will be discussing regarding the, what are the
various environmental protection agencies in India. What are the, which are the various
environmental acts?

There are various standards, we will try to learn regarding the discharge standards, water
treatment standards, and there are certain interesting things with respect to which is called as
environmental impact assessment. So, we will be discussing only briefly regarding this, we will
not be going into details, but to give an idea that we must know all these things, this is very
important for environmental protection and in particular for wastewater treatment.

(Refer Slide Time: 1:48)

So, starting with there are many environmental laws and reinforcing agencies in India and which
actually help in preventing the further environmental degradation and taking care of the
environmental laws, which are made by these agencies and other agencies, which actually
enforce these laws.
So, it all started earlier, there was in 1972, a National Council of Environmental Planning and
Co-ordination was set up and under the Department of Science and Technology. And this council
was set up so as to understand the needs of water, air and soil pollution, which will be there.

Now, after that another committee was set up in 1980 to review the existing legislations and
administrative machinery, which actually build up little bit after the we got our independence
and in particular, after 1972.

And these machinery, which were there for environmental protection and for recommending
ideas to strengthen the existing laws and environmental agency is at this particular committee
was highly helpful. And because of this committee, a separate department of environment was
set up and which was further upgraded into full- fledged Ministry of Environment and Forest in
1985.

So, and in between the government of India passed some rules and regulations related to water
pollution and control and similarly with respect to air pollution and control. So, these laws were
made before actually this full- fledged ministry was made in 1985. Right now, this Ministry of
environment forest was renamed as Ministry of Environment forests and climate change, because
the climate change issues are now becoming more and more important.

So, this was also incorporated within this ministry. And this is the nodal agency for planning
promotion, making environmental laws and enforcing the laws as well. Now, along with this
particular ministry, there are other ministries, which are related to environment and water in
particular. So, there is a ministry of Jal Shakti, or water and within that, there are two
departments, one is called department of drinking water and sanitation.

So, this department in particular takes care of water drinking water availability and also
sanitation all throughout the country. Similarly, there is a Department of Water Resources, river
development and Ganga rejuvenation. So, since Ganga is one of the important rivers, so it tries
to, along with the Ganga, for other river development and development of other water resources,
this department takes care of all throughout the country and this is within the ministry of Jal
Shakti.
Ministry of Rural Development, Ministry of road transport and highways, which includes the
waterways also they have important role to play in the protection of environment and water
related activities. Similarly, the ministry of Culture has a role to play in all such activities.

(Refer Slide Time: 5:19)

Along with these ministries, there are many agencies, which are there, which are related to
environment and its control and all the pollution aspects they are taking care of. So, two most
important agencies are like CPCB. So, CPCB at the central level this is called Central pollution
control board.

So, actually it mandates whenever there is a problem, it understand okay there is a new type of
issues are evolving with respect to environment, or pollution. So, they always make a committee
and depending upon the committee's new rules, regulations etc., may be made.

And then there are there are state pollution control boards, which are there in each and every
state. Similarly, there are union territories environmental committees, which are there each and
every environmental Union Territory. And they have to see that the whatever rules and
regulations are made by the ministry, or center pollution control board, they have to be enforced.

So, enforcement lies with the state pollution control board and UT environmental committees.
Sometimes these state pollution control board and UT environmental committees can also have a
stricter, standard with respect to discharge up any water from any industry, or otherwise.
So, they can make little bit standards another thing, but generally they are in general enforcement
agencies as compared to law making industries. In addition, there is a forest Survey of India,
Wildlife Institute of India, the National afforestation and eco development board, the botanical
and Geological Survey of India. They are highly engaged in environmental related activities.

Similarly, groundwater board and central groundwater authority are agencies which are related to
groundwater. And they see that what is the amount of groundwater available beneath the ground
in any reason and what is the, what is the level of composition of various, impurities, which are
there in these groundwater where whether that groundwater is good enough for drinking, or it has
to be treated further for drinking, or for irrigation also.

These groundwater boards continuously perform surveys and also testing for their uses of the
groundwater for drinking, or any other uses.

(Refer Slide Time: 7:53)

Now, there are many acts, rules and laws have been made in India with respect to environment.
And these may be categorized into various categories like water pollution, the acts and rules
related to water pollution, air pollution, environmental protection in general, public liability
insurance act, then National Environment appellate authority was made under these rules and etc.

Then national environment tribunal, animal welfare, wildlife, forest conservation, biodiversity
and IFS Indian Forest Service. So, there are different categories of Acts and rules. So, we are
more interested in water pollution acts and rules. So, we will be discussing those.
(Refer Slide Time: 8:52)

Now, one of the first water pollution related act was made in 1974 and it was called as Water
Prevention and Control of Pollution Act 1974. And it was amended in 1988 also. Similarly, there
was a Cess act related to water prevention and control Cess act. It was made in 1977 and it was
amended in 1992. So, these were one of the first few acts related to water.

(Refer Slide Time: 9:19)

Now, regarding the Water Prevention and Control of Pollution Act 1974. So it provided for the
prevention and control of water, water pollution, and the maintenance and restoration of
wholesomeness of water in various aquatic bodies, including rivers, lakes, and reservoirs.
So, any human activity, which was having a bearing on the water quality of these aquatic bodies
all such human activities were covered under this act of 1974. And under this act, no provision
with no person without the previous consent of the state pollution control board can establish any
industry, or operate any industry are can perform any treatment of disposable system.

In any such activity cannot be performed without the consent of the state pollution control board.
So, it was one of the major points of this act. Also, it gave the consent to establish industry and
after establishing the consent to operate the industry. So, this was provided by this act.

(Refer Slide Time: 10:42)

After that there was Cess Act 1977, And that was passed and it was done to levy and collect cess
on water consumed by the certain categories of industry. So, this was done because if many
industries take lot of groundwater. Now, if the water is after uses up that water in the industry,
the water is being getting discharged in form of wastewater.

Now, if the wastewater pollution load is high, what they do is that they take out further water
from the groundwater and dilute the water. So, it will come within the permissible limits. So, that
is how they were actually taking more, they may take more groundwater from the ground, and
thus, the groundwater levels were going down. So it this act actually levied Cess on the water
consumed by these industries. The money thus collected was to be is used by CPCB and SPCB
to prevent and control the water pollution. So, this is there.
(Refer Slide Time: 11:50)

Then after in 1986. This is a umbrella Act was passed and this was foreseen after the Bhopal Gas
Tragedy. After the Bhopal Gas Tragedy, the government of India felt that we should have a
umbrella Environmental Protection Act and it was made in 1986. Under Article 253 of the
Constitution. The act was passed in May 1986. And it came into existing in November 1986.

And this is considered Umbrella Act related to environment, because many other rules
regulations et cetera have been passed under this Environment Protection Act. Now, the
objective of this act was for the protection and improvement of the environment. And it actually
gave a lot of power to central government to establish various authorities.

And these authorities were further given mandate for preventing the environmental pollution in
all its form and also if any specific problem is arising and they see, so they can do studies and
further make acts and rules. So, this was there. It was amended in 1991. And in 1994, there was a
very important act rule related to environmental impact assessment was passed and that we will
discuss later.
(Refer Slide Time: 13:32)

Now within this 1986 Act, several rules related to various aspects of management of hazardous
chemical waste, etc., have been notified, also under this act central government has acted
rusticated, prohibited a lot of industries in different areas to safeguard the environment.

Many standards, the standards with respect to what should be the quality of air, or water from in
any reason, or for various uses, or for also for discharge of effluent from these industries,
similarly with respect to noise have been evolved and notified under this Environmental
Protection Act 1986.

So, this is considered an Umbrella Act. And under this, there are procedures safeguards
provision and restrictions on the handling of hazardous waste. Similarly, a lot of new types of
categories of waste are also being notified under this act including like E-waste, battery waste,
hospital waste. So, everything is coming under this Environmental Protection Act 1986.
(Refer Slide Time: 15:34)

Now, these acts and rules, they also define certain duties of Indian citizen with respect to
environment and legislations alone are not the remedy for the environmental management. So, it
is our responsibility to strive to protect the environment for the present. And we should do all
these things, so that we can the future generations must not be deprived of their resources and
they must get all the resources that we are getting.

So, this is very importance of these duties were defined also under these acts and rules.
Conservation, recycle, reuse, they are absorbed all around the environmental pollution acts and
rules, but there are issues which are there with respect to enforcement of these acts and rules by
the state pollution control board, or by central pollution control board, or UT environmental
committees.

We must understand as citizen that there are only a limited number of persons working in these
agencies. So, it is our duty to protect the environment, if any industry we foresee that we see that
they are not following the rules and regulations, maybe we must convey this to the agencies. So,
that those industries must start following all the acts and regulations and also do not degrade the
environment.

The problem of environmental degradation is a very, very complex and it requires a multi-
dimensional approach. So, it is also the duty of the citizens to take care of all these aspects.
(Refer Slide Time: 16:58)

Now, there are many standards have been made for protecting the environment. So, there is a one
standard which is not I am not listed here, there is standards with respect to air emission also,
there is standards with respect to noise, but in this course, we will be since we are concentrating
only on wastewater treatment. So, we have mentioned only the standard which are there with
respect to water.

So, one of the first standard, which is there with respect to general standards for discharge of
environmental pollutants. And in particular for effluents, which are discharged from industries
for those cases, there are certain maximum allowed concentration. So, that means, this is for
suspended solid in this particular unit milligram per liter. This is the maximum allowed
concentration.

Now, in India, I had told that any water discharged from industry may have different uses, we
may have to discharge the effluent to the surface water to the public sewer, for irrigation in the
agricultural fields, and it is possible that we may have to discharge effluent to in the marine, or
coastal areas.

So, for in India there are different sets of maximum allowed concentration limits for all these
four categories. And these four categories are like inland surface water, public sewers, because
public sewers are further been treated. So, here there is a relaxation if any industry discharges
any of its effluent to the public sewer.

Now, if that industry water can be used for irrigation, then certainly the limits are a little bit
relaxed, because for irrigation we can use the treated water. Now, similarly for marine and
coastal areas standards are there. So, we can see there are four different standard limits, many
times they are same, many times all four have different values, depending upon the parameter for
which standard is being set. So, these are called general standards.

Now, there is another industry specific standards also, which have been made in India. So, we
will be discussing that later on. So, we can see here there are different sets of parameters like
suspended solids, particle size of suspended solids. A pH value worksheet with a pH value.

So, we can see the general limit is from 5.5 to 9, but it may be it may be much lower range may
also be there, it may be 6 to 7 also depending upon the industry. Similarly, for temperature there
is also a rule and then oil and grease.
(Refer Slide Time: 19:55)
So, there we can see total residual chlorine, Ammonical nitrogen, total kjeldahl nitrogen, free
ammonia, BOD, 3 days at 27 degrees centigrade, COD, Arsenic, Mercury, Lead, Cadmium,
hexavalent, chromium, total chromium.

So, we can see a large number of parameters are listed sulfide, phenolic compounds, radioactive
materials are also listed if they are likely to be present. Then some bio assay tests, etc., can be
performed, Vanadium, Nitrate Nitrogen etc. So, all these limits have been set.
(Refer Slide Time: 20:32)

Now, what happens that earlier I have told, so these are limits have to be followed by industry. In
addition there are industry specific limits also, where for some key parameters the limits will be
much lower than what is mentioned in the general standard.

Now, there is a possibility as mentioned earlier that these industries may start using more amount
of water and dilute these effluent. So, that the standard limits may become less. So, there is after
studying the technology, which is there in any industry some wastewater general generation
Standards have been also device.
So, what are these that how much amount of water can be used per tonne of any finished product.
So, like for integrated iron steel it is 16 meter cube per tonne of finished steel. Similarly, for
suger 0.4 meter cube. So, there are a large number of standards which are like how much
wastewater can be generated, it is not that we can generate any amount of water and it is related
to how much amount of any finished product is being produced.

So, there are standards are pulp and paper industry, sugar industry, iron and steel. Then
fermentation industries. So, these all those industries, which use very large amount of water
these wastewater generation standards have been set.

(Refer Slide Time: 22:08)

Similarly, load based standards have been set, that how much oil and grease you can generate per
tonne of any finished product, or raw material process. So, if you process this much amount of
raw material, how much amount of any particular pollutant you can generate, or any particular
parameter what should be the maximum value.

So, for petroleum oil refinery you can see here, oil and grease can be maximum 2 kg per 1000
tonne of crude process. So, there are a number of other standards you can parameters you can see
here. They are listed BOD, COD, suspended solids, phenols, Sulphides, cyanides, ammonia and
many others. Similarly, for petroleum oil refinery, these parameters have been set. For large
scale pulp and paper mill etc. These standards are set.
(Refer Slide Time: 23:09)

So, in addition to various standards, which are generally standards. Minimal national standards
have been specified by CPCB, for various types of industries. And these MINAS standards vary
from industry to industry. So, CPCB actually laid down a specific standard for effluent discharge
from these industries and the standards a clear made taking care of the techno economic
feasibility of the processes which are being followed in that industry.

So, that means, we were trying to see that the economic aspects are still met while following
these minimal national standards. And under these standard these MINAS standards can never be
relaxed. So, and SPCB, the state pollution control board has to see that always these minimal
national standards are being followed.

Now, the MINAS standards can further be made stricter by the state pollution control boards, if
they find that okay, there is a requirement of making these standards stricter in that particular
reason of that the state, or in the overall all the parts of the state. So, this is SPCB, the state
pollution control board is empowered to make these standards restricted, but can never be
relaxed under any condition.
(Refer Slide Time: 24:49)

So, this is the one example is given for here coke-oven industries. We can see these are the
standards which have been laid down under the EPA notification 1988. And we can see one of
the key parameters like cyanide is mentioned here. So, cyanide is one of the important
parameters, it is for coke-oven industry.

So, they have made it a specific maximum concentration limit with respect to cyanide, oil and
grease as well as ammonical nitrogen from these industries so along with the phenolic
compounds. So, similarly MINAS standards have been made for a large number of industries.
And there have different sets of parameters, which may be industry specific like for tannery there
is a parameter for chromium.

Similarly, for another industries depending upon the raw material being used, and the product
being produced, other parameters may be different, but they are likely to be stricter with respect
to general standards which have been made.
(Refer Slide Time: 26:01)

Now, in addition to this minimal national standard, the CPCB also has developed a concept of
designated best use of any water body, depending upon the water quality, which is present in that
aquatic body and this is called as primary water quality criteria. And this depends upon the
characteristics of water, which is there in that aquatic body. So, there are five such designated
best uses, which have been prescribed by CPCB.

(Refer Slide Time: 26:37)

And they are listed in this particular slide. So, that if the source without conventional treatment,
but after disinfection has these sets of it is meeting these sets of criteria, that total coliform
organism in terms of MPN per 100 ML is less than 50, if pH is between 6.5 and 8.5, DO is above
6 milligram per liter and BOD5, or BOD3 depending. So, it is within the standard, then it is
classified as the water quality criteria A.

Similarly, for outdoor bathing, these are the standards. So, any water body, which meets this
criteria can be used for bathing. Otherwise, we have to see that there should be no bathing done
in that water body. Similarly, for there is C, D, and E class. And these are the designated best
uses and how like for irrigation, industrial cooling and controlled waste disposal, the pH should
be between 6 and 8.5.

Electrical conductivity at 25 degrees centigrade should be maximum 2250 micro moles per
centimeter. Then similarly sodium absorption ratio for irrigation should be maximum 26 and
boron should be maximum 2 milligram per liter. So, these are the different standards with respect
to water quality criteria that have been set.
(Refer Slide Time: 28:28)

In addition, there are there are few things that we should follow and under that there is
environmental ethics for the industries and there is a term which is called as environmental
impact assessment and this is very, very important. So, environmental ethics actually, the
industries by themselves should develop a practice by themselves so, as not to degrade the
environment or pollute the environment by any means.

And during this environmental ethics, it also includes that all these industries and the society as
large should use the resources and other things in such a manner that economic sustainability is
attained. However, it is also seen that ecological sustainability and social sustainability is also
attained. So, this everything, all the three aspects economic, ecological and social sustainability,
they fall within the category of environmental ethics.
(Refer Slide Time: 29:40)

In addition, there is a term which is called as environmental impact assessment this is very, very
important term and this was, this is under the rules of the Government of India. And this has to
be this tool, or this impact assessment study has to be performed by each and every industry and
many projects before actually the project is implemented at the ground level.

And this tool actually gives us the decision making capability. So, what does it do that in this
EIA study, we have to perform a lot of studies with respect to air, soil, groundwater, ecology,
and many other things that what will be the damage that will happen if that project is
implemented.

So, for assessing this damage, what we have to do is that, we have to assess the present
environmental conditions, which are there in that particular region, when there is, when that
project is not implemented, and once the project is implemented, what will be the condition that
will be there.

So, there are certain sets of rules, guidelines and other things are there and methodologies are
there under EIA, and which help in performing this environmental impact assessment beforehand
and via this we can decide whether that project has to be implemented or not. If there is a
possibility of implementation of that project, what are the various technologies and other things
that we can follow said that the impact on the environment is minimal.
If there is any impact on the environment, how we will take care of that impact, so, that it is
further minimized, so, that there is virtually no impact on the environment. So, this EIA has been
made a prerequisite for setting up any new project or renewal of license of old and existing
plants. So, if the license has to be renewed, then we have to perform this EIA study.

(Refer Slide Time: 32:01)

So, there are many projects and activities which require environmental clearances and they are
listed here just for knowledge, we will not be discussing much in detail, but this is just for
knowledge, like in the, like for mining, extraction of natural resources and power generation, we
can see the various activities which are listed like mining of minerals, we can see thermal power
plants, river valley projects, nuclear power projects, so, all these depending upon the various.

Now, these activity have a threshold limit that how much amount of activity is going to be
performed. So, what is the area of that project? So, there are other conditions also possible. So,
all these are listed here and similarly, coal washeries, mineral beneficiation, all these are listed
within this.
(Refer Slide Time: 32:59)

Now, materials if any materials have to be produced, these activities are also there metallurgical
industries, cement plants because they are producing new type of things.

(Refer Slide Time: 33:10)

Similarly, materials processing like petroleum refining, coke oven plants, asbestos milling, chlor-
alkali industries, soda ash industry, leather, skin, hide processing industry. So, all these industry
actually process some of the raw material and convert into some product. So, all these industries
are listed.
(Refer Slide Time: 33:30)
Similarly, manufacturing and fabrication, chemical fertilizer, pesticide industry, petrochemical.
So, we can see here a large number of industries are listed and all these industries need to take
environmental clearances. And these industries and projects include the service sectors also.
Suppose any transportation gas pipeline has to be made, then isolated storage of, a storage depot
of hazardous chemicals have to be made.

So, all these services, sectors and various other physical infrastructure all these activities require
environmental clearance and also EIA studies have to be performed. And within these EIA
studies, wastewater treatment or water treatment is very important aspect of all these studies, it is
one of the most important parameter after air which is taken into consideration in performing
these studies.

(Refer Slide Time: 34:39)

Now, there are some general conditions also with respect to implementation of these projects or
activities and generally all A category projects, they are considered as A category projects. For
them EIA is mandatory. For Category B projects which generally fall, which are similar to
category A but their capacity or amount of production is much lower.

So, for them there is some relaxation. But if that category B project, if it is located in such a
place that it is within 10 kilometers from the boundary of protected areas notified by wildlife,
then it will fall into category A and EIA will be mandatory.

Similarly, all those category B projects, which are in critically polluted areas also they have to
be, they fall, they are considered as category A projects. Similarly, if they are present in the Eco
sensitive area or interstate boundaries near to interstate boundaries or international boundaries,
then also EIA is made mandatory.
(Refer Slide Time: 36:00)

From all these things we understand that that EIA, environment, pollution and we have to see
that how the environment conditions are maintained, we are polluting the environment in
minimal. So, all these things are very important and within that water pollution and wastewater
treatment, water treatment and wastewater treatment is very important and that we are going to
start learning in the next few lectures.

Before that from today's lecture, we understand few other things also. Now, in each of the
standards, we have seen, there are a large number of parameters that are listed. Now, if these
parameters are there, we must understand the physical significance of these parameters until
unless we know the physical significance of these parameters, water quality parameters, which
were there like BOD, COD, total cyanide, total chromium, all these parameters.

So, if we do not understand the basic, and we do not have the basic understanding of these
parameters, we can never perform the treatment or we can never understand that how to use any
technology or which technology has to be used for which purposes. So, we will start with
understanding the water quality parameters in the next lecture. So, this is there, with this we end
today's lecture. Thank you.