Thursday, November 6, 2014

The Accursed Country of Power Production: What is the Way Out?

Today I was reading an article written by Priyadarshini Sen published recently by the Outlook Magazine as one of its national cover story. The article is titled 'Accursed County' and it deals with the negative side of the thoughtless infrastructural development that has been taking place in India in the past. 

If you have not read this article, I suggest you read it online by clicking the hyper-linked title above.

The author has painstakingly brought out the severe air, water and land pollution that apparently results from the several thermal power plants that have been in operation in and around Sonbhadra district of Uttar Pradesh state.

This district, from techno-commercial angle, is ideal for setting up of thermal power plants. In and around there are coal mines that produce coal suitable for power generation. It has abundant source of water from Sone River and it tributary, the Rihand River and the artificial dam built across the latter creating the Gobind Ballabh Pant Sagar reservoir. More importantly, the district provided vast tracts of inexpensive land for setting up the power plants.

And this techno-commercial viability naturally attracted the public sector and private sector industrial enterprises to set up their thermal power stations in this place. Sonbhadra now produces about 11000 MW of electrical power which is about 10 % of the gross thermal power production capacity of India. It is a very good contribution to power starved India.

Those associated with the power industry and those advocates of fast track development naturally dismiss the environmental adversities as nothing serious. For every good thing, there will be some bad effects as well. They say.

But can it be dismissed that way? Shouldn't we a bit more concerned? Should we not be concerned with the poor populace of the place who are the victims (of pollution)? Shouldn't we concerned with the health problems of the people living here?

This is the issue that the author of the outlook cover story highlights. 

What are the reasons for pollution from thermal power plants? Can we not eliminate it? 

Being a technical person associated with various aspects of thermal power plant design, operation, maintenance and also its complex technicalities of environmental pollution control, I personally feel that the thermal power plant pollution effects can be mitigated to a large extent, provided the people concerned with the thermal power plant industry are a bit more technically and administratively serious with the matter.

First, let us understand the common cause for the pollution problem attributable to thermal power plants. 

Thermal power plants generate electricity by running steam turbines that drive large electric alternators commonly called generators. The steam turbines rotate at high speeds due to the energy transmitted through high pressure steam which is produced in large boilers by burning pulverized coal.

Coal which normally lies hundreds of meters below earth, contains essentially carbon and hydrocarbon compounds. The carbon and carbon compounds gives coal its calorific value or fuel value. Coal also has several mineral compounds within its complex structure which do not have any fuel value. It is generally called the coal ash.

The main constituent of coal ash is silica (silicon dioxide). It also has other mineral oxides and compounds of aluminium, magnesium and also small quantities of minerals containing mercury, phosphorous, etc. Some coal ash may also contain very small quantities of radio active minerals.

The carbon compounds of coal burns and produce heat energy and some gases such as Carbon dioxide, nitrous oxides, water vapor, hydrogen sulfide, etc. For aiding burning of coal, large quantities of air is required and while burning the oxygen in air is consumed and the rest gases are let out through the chimneys which contains other gaseous products of coal combustion.

The non fuel mineral content of coal does not burn. It comes out as ash particles after coal combustion. Indian coals contain large quantities of ash, as high as 45%. Every one ton of coal burnt produces nearly half a ton of ash.

Large thermal power plants use pulverized coal for efficient burning. Pulverized coal is coal which is finely powdered in coal mills which when carried with air behaves almost like a gaseous fuel.

Thus the ash which comes out of pulverized coal burning in thermal power plants is in the form of fine particles. This ash is commonly called the 'fly ash'. If left out it also gets discharged in to the atmosphere through the chimneys along with the chimney gases. A 100 MW power plant burns nearly 1000 tonnes of coal per hour. If the ash content of coal is 30% that means it has the potential to discharge 300 tonnes of ash dust to the atmosphere every hour! With that kind of a dust discharge, no one could live near a power plant!

Thermal power plants therefore use many air pollution control equipment to control the pollution caused from fly ash that could discharge out from it.  

The best fly ash arresting equipment is the electro-static precipitator or ESP. When designed and operated properly, it can remove fly ash from the chimney gases almost entirely. The fly ash removal efficiency of an ESP could be as high as 99.999%. Nevertheless, this efficiency can drop much when the ESPs are either with inferior design or operated without care or without proper maintenance.

Besides, the ESPs cannot tackle the pollution caused by gaseous pollutants like the oxides of carbon, sulphur, nitrogen etc. 

The fly ash arrested by the ESPs are either collected in dry form and could be used to make pozzolana grade cements. It can also be used to make fly ash bricks. In most power plants, the fly ash is made as a slurry using water and discharged in to a large holding reservoir called the ash pond. Normally, the ash pond is designed to hold the ash produced in a power plant for about 50 years. A filled up ash pond could be a source for raw material for making fly ash bricks. The government of India has recently made it compulsory for all builders and colonizers to use fly ash bricks for reducing the pile up of fly ash in the thermal power plant ash ponds.

Nature has an in built capacity to absorb and degrade all normal pollution caused by human activities. However, when this natural capacity is exceeded, we need to have artificial pollution control systems.

Now let us see what has created the Sonbhadra syndrome. First the ideal techno-economics have caused a concentration of power plants in this area overlooking the natural limits of the region to absorb environmental impacts. While it could have possibly withstood the impact of 2000 MW of thermal power generation, the authorities have allowed it to have 11000 MW thermal power production. This problem is not unique to Sonebhadra. Korba district of Chhattisgarh State which is another power hub of India which may also be an environmentally failed zone if not managed properly!

These areas are burning millions of tonnes of coal an hour. Imagine the oxygen depletion in these districts! Will the green forests of these areas replenish this much oxygen? Perhaps not.

The designers of the power plants ask for various input data such as the average ash content for designing their ESPs. Suppose that they had designed the plants with a maximum ash content of 30% and now the plants are getting coal with average ash content above that limit. Obviously, the power plant chimneys spew the balance fly ash to the atmosphere. Imagine the quantum of hourly tonnes of fly ash getting distributed to the atmosphere through the power plant chimneys in such a situation! In case the power plants do not get operated properly with regard to the air pollution control norms, the ambient air quality of the area deteriorates from what is stipulated as admissible by the central pollution control board. Poor ambient air quality caused by the thermal power plants enhances the level of particulate matter (PM) and respirable suspended particulate matter (RSPM) in the ambient air. The particulates dispersed to air from power plant chimneys might contain toxic element compounds such a mercury, arsenic, phosphorous, sulphur and the like. When exposed to it for a long term, they could cause serious health hazards to people.

Improper operation and management of the power plants with regard to air, water and land pollution control methodologies adversely affect the environment around the thermal power plants. This happens due to various reasons such as production vs. pollution control priorities of the plant management, inadequate pollution control facilities and incompetence of the plant personnel in understanding pollution causes and its abatement. Of these, the latter plays a very important role.

Thermal power plants generally employ mechanical and electrical engineers for the operation and maintenance of the plants. These engineers are mostly concerned with power production and they are often pressurized to meet the production targets at any cost. The major concern for them is to get the coal, unload it, store it, pulverize it, burn it and run their turbo-generators. These are the operation and maintenance tasks of the mechanical engineers. The electrical engineers of the power station look after the electrical tie lines, the electrical switch gear and the auxiliary equipment electrics. The priorities for all of them are for maintaining the production and the plant load factor. The pollution control equipment operation and maintenance are also entrusted among this group. Pollution control equipment and systems are viewed as those creating obstructions to production and there is always a tendency for the plant personnel to give low priority for maintaining them under the best performance levels.

Thermal power plants also may have a small group of technical people who are entrusted with the water, water treatment, laboratory tests for ensuring equipment performance, quality, etc. They may also be entrusted with the task of pollution monitoring.

In a thermal power station in India, the stress is for production. The power station management personnel are often from the group of engineers associated with mechanical or electrical operations who have been conventionally trained to work hard for achieving high production targets. They are trained to ignore any thing that hampers production or any thing that causes a lowering of production.

Thus air pollution control and other pollution control or quality control aspects become pinching issues for the majority technical personnel and the top management authorities of all thermal power stations in India. With the result that they try to be dominant over all issues concerned with pollution control or quality control. This is a fact of the day.

Indian thermal power stations do not employ trained chemical engineers who have interdisciplinary technical back ground to develop as technical experts who could effectively understand and tackle the intricate technical problems of environment, water, air and the land and its linkages to the various production processes involving fuel and burner management, water management, steam generation, etc.

Some three and a half decades ago, by working in a thermal power plant as a lone chemical engineer I could experience this problem. It was a well thought experimental idea of some visionary management team of those years that could induct me to the thermal power plant. Under normal circumstances, then or now, chemical engineers are hardly inducted in thermal power plants!

In a thermal power power station, if the ESP efficiency is down by 1 % the effect could be catastrophic in the long run. On the other hand, by overlooking the ESP efficiency, the plant operation personnel might be able to enhance the production to some extent. Production and pollution control are two antagonistic agendas in the Indian industry in general.

Awareness programs and punitive initiatives under pollution control perhaps have done some impact. But what is lacking now is the technical knowledge and the expertise to tackle the environmental issues confidently. The environmentalists of India are mostly academicians and theoreticians who make hue and cries outside and not work inside to actually do some real work to eliminate pollution cost effectively! In India, there is hardly any mobility of engineers between Research and Development, academics and the industry. Either sides are maintained too water tight for that to happen.

India has grossly neglected the need for training chemical engineers who are with the basic knowledge to tackle many interdisciplinary technical issues when they are exposed and trained in the real technical fields. This has happened because, the few trained chemical engineers did not find opportunities within India to prove their expertise and develop. The Indian industry recruiters and policy makers unfortunately have little idea about the usefulness of chemical engineers. Many even do not understand the difference between a chemist and a chemical engineer! For example, the thermal power industry of India with all the need for chemical engineers seldom thought about it! In India things go as per conventions and no one hardly think of changing the conventions. Changing the conventions can only be done by progressive societies and progressive people with higher intellectual capacities! India lacks such people in key leadership positions!

Now, as chemical engineering training has become almost non existent in India, it is all the more difficult for getting good chemical engineers for the various interdisciplinary tasks such as that posed by environmental pollution control and utility system engineering.

All these are essentially because of vested interest individuals with inadequate expertise who are in academics and policy planning in India. So long as expertise is something determined by the ability of a person to hoodwink the nominating authorities, this situation is not going to change in this country.

Pollution control laws and enforcement in India have been very lenient. Environmental regulations have also become a tool used by the authorities to exert their control over the industry rather than using it honestly for the benefit of the people. This results in severely polluting industries escaping from any punitive actions while new projects getting unduly delayed for environmental clearances.

It is time that we set aside self interests and move towards greater national interests. When that happens, our country would no longer have accursed counties. It will have only blessed counties! And India would indeed become 'Swachh Bharat' (Clean India) as envisaged by its visionary new PM, Shri Narendra Modi. 

India has no dearth of technical expertise to manage problems of this nature. What it really lacks is the will, honesty and administrative competence of its key functionaries holding key governmental positions!

Let us earnestly hope for positive changes in the near future!

2 comments:

  1. Dear Rajan, thanks for the insightful information that can be used in reducing the toxicity generation in our thermal plants. I hope and pray that the new Modi govt would take these and similar suggestion as part of the 'swachh bharat abhiyaan'.

    ReplyDelete
  2. With the excessive amount of fly ash released every year from coal-fired power plants, luckily we got an option to turn this ash residue into useful construction material. Yes, by promoting the usage of fly ash bricks in our construction industry we could enjoy the benefits of this innovative technology and save our environment.

    ReplyDelete

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