German experience on compliance of environmental norms by thermal power generation companies Prof. Dr. W.A. Benesch Director Energy Technologies STEAG Energy Services Germany
Rough development of environmental protection in Germany 30.1.2017 2
Background in India The Ministry of Environment, Forest & Climate Change has, in Dec.2015, notified the revised standards for coal-based Thermal Power Plants in India The new standards are aimed at reducing emission of PM10 0.98 kg/mwh sulphurdioxide 7.3 Kg/MWh and nitrogen oxides 4.8 kg/mwh control of mercury emission (at about 70-90%) as a cobenefit. Limiting the use of water in thermal power plant will lead to water conservation about 1.5 m³/mwh) 30.1.2017 3
Challenges and issues implementing the new norms Available technological solutions need to be adapted to suit Indian conditions. The legal framework has to be adopted according to new technical solutions. High cost of retrofits and its impact on tariff have to be minimized. So experiences from retrofit in other countries have to be consequently used. 30.1.2017 4
Legal framework According to the technical opportunities of the new emission reduction technologies it is recommended to adopt the existing legal frame work in India respectively. Currently the legal framework is giving technical and environmental optimum boundary conditions for power plants with only particulate matter reduction. 30.1.2017 5
Examples for the recommended adaptation of the legal framework Examples of items that have to be discussed for power plants having additional flue gas treatment measures are: Height of stack (Is a 275m stack needed for plants that have reduced their emissions extremely?) Exhaust temperature of flue gases, reheat or no reheat (At what temperature should the flue gases leave the stack? Is a wet stack allowed? Would there be a reheating of flue gases asked for?) Flue gas exhaust via cooling tower (Would be an emission of flue gases through the cooling tower be allowed which is quite common in modern ultra supercritical German power plants?) 30.1.2017 6
Legal framework continued Water consumption and wet FGD (Due to limited water resources water consumption has to be minimized. On the other hand landfill of byproducts should be avoided. To produce a salable gypsum, water is needed for the process.) Bypass needed or not (In earlier days in Europe bypasses had been implemented to allow in case of failure of the flue gas treatment facilities to continue power plant operation but with higher emissions. Currently the equipment is so reliable that no costly bypasses are needed.) Conditions and location of measurement of emission values ( The measurement of the emission values has to be defined precisely average timing location of measurement, O 2 content of the flue gases and so on) Ash content of coal (All of the power plant equipment including all the new flue gas treatment plants, have to be dimensioned according to the coal used. Would it make sense to use and mandate the use of washed coal instead transporting and combusting a coal with 50% of ash?) 30.1.2017 7
Influence of coal quality on different parts of power stations. Especially the new flue gas treatment plants. DENOX 30.1.2017 8
Legal framework continued Will special technologies like sea water FGD be allowed? Reuse of byproducts should be defined. Ammonia storage and transportation concepts should be compared (aqueous ammonia, ammonia water, urea) and so on Anyhow the first step reducing pollutant-emissions should be the increase of the plant efficiency. By this it is possible: to reduce the fuel consumption together with the emission rates of all air polluting matters. How far this can be integrated in the legal frame work has to be discussed too. The question has to be raised: What flexibility for overall environmental friendly, economic solutions is existing? 30.1.2017 9
Organization and management of the retrofit projects, Solid base data set Experience in Europe and especially Germany has shown that overall cost savings are possible if the owner and operator of existing power station provides all necessary data like: boiler and combustion system design currently and in future used coals temperature profile over the boiler typical NO x, SO 2 and particulate matter distribution profiles over the cross section of exhaust gas ducts. Based on this information specifications can be prepared. Tendering process on this solid foundation avoids comparing apples with pears. As a result the owner and operator of the power stations will get technical and commercial comparable and attractive offers. 30.1.2017 10
Synergies can help to reduce costs Especially considering new plants needing the full set of reduction measures (NO x, particulate matter, SO x and mercury), a joint approach is recommended instead of adding individual solutions and components for particulate matter, NO x and SO 2. Synergies can help to make the whole process more efficient, technical less complex and at least less costly Examples are: Only one fan instead of three to cover the pressure loss of the existing boiler, the SCR and FGD itemps.ca/ http://www.formations-quali Overall water balance including opportunities of water reuse Optimized temperature balance and heat recovery Aspects of particulate matter reduction in ESP and additional FGD 30.1.2017 11
Project management and quality issues The tight time schedule for implementation of the new environmental norms asks for: optimum project management starting with collection of all base data needed over basic design and specifying the retrofit measures, ending with proper erection and quality control. After selection of the supplier the design control, based on operating experience with such kind of flue gas treatment plants should be started. Quality control is essential. Here especially experience with new materials for power plants like rubber lining and fiber reinforced plastics has a very high value. 30.1.2017 12
Summing up It is recommended to adopt the regular frame work to the new task. Base data collection should be done by the owner. Use of synergies reduces costs. Ash content of coal should be minimized. 30.1.2017 13