24 th World Gas Conference, Buenos Aires, Argentina Authors

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1 24 th World Gas Conference, Buenos Aires, Argentina 2009 DEVELOPMENT AND IMPLEMENTATION OF A NATURAL GAS LEAK REDUCTION PROGRAM FOR PRESSURE REGULATING STATIONS IN THE MOSGAZ GAS DISTRIBUTION SYSTEM IN MOSCOW, RUSSIA Authors J.B.W. Wikkerink (Kiwa Gas Technology, Apeldoorn, The Netherlands), V. Duynhouwer (Lighthouse Russia, Moscow, Russia), A.A. Kljuchnikov (Mosgaz, Moscow, Russia) Keywords: 1. Leak Mitigation; 2. Gas Regulating Station(s); 3. Methane Emission Reduction; 4. Mosgaz; 5. Sealants; 6. Gaskets

2 ABSTRACT Limiting greenhouse gas emissions is vital to curb the effects of global warming. Natural gas (methane) is the second most serious source for greenhouse gas emissions, next to carbon dioxide, contributing to global warming and climate change. Therefore it is important that the emission of natural gas is reduced as much as possible, all the more that the weight-equivalent contribution to global warming of natural gas is 23 times higher as compared to carbon dioxide. For this purpose a project was started in 2007 with the aim of limiting the emission of natural gas for a number of gas distribution stations in Moscow. It was expected that a considerable emission reduction could be demonstrated with the application of new technologies, such as the use of new types of sealing materials, installation techniques and the use of modern leak detection apparatus. A minimum reduction of 90% of the initial emission was stated as the target. The technical part of the project consisted globally of the following steps: - Development of a repairs scheme; - Identification, classification and quantification of leaks; - Training of the staff of Mosgaz on leak detection, leak rate flow measurement and repair of leakages (theoretical training in The Netherlands and training on the job in Moscow); - Preparation of a procedure for the selection of a few stations (10) whose contribution to the natural gas emission is representative for all 396 stations in use by Mosgaz; - Selection of five stations for repair; - Execution of repair activities (replacement of sealants and gaskets) by the staff of Mosgaz; - Evaluation of the project. The program was implemented and after the leak repairs were made, it turned out that the leak quantity had been reduced by 98.7%, resulting in a saving of about 68,000 m 3 gas annually (after the repairs only one leakage remained). This means that the target of 90% has been fulfilled amply. None of the detected leaks affected safety (< 5 m 3 /h), but the amount of gas leaking over a year was considerable. Assuming that the 10 selected stations were representative of all stations, a potential reduction of about 5 million cubic metres annually is achievable for all 396 stations. It should be noted that this is a rough estimate, as more stations have to be investigated for a better estimate. It has also been observed that certain stations have much more leakage than others. If the repair activities would only be focussed on the larger leaks, then the quantity of work will be limited considerably, with an acceptable result. A reduction of 4 million cubic metres might be achieved by this way of working. Mosgaz has a good maintenance program for the stations for as far as security plays a role. However, there is less focus on the smaller leakages, which do not affect safety. It might be expected that the leakages which have been found at Mosgaz will also be found in stations elsewhere in Eastern Europe. A selective repair program could help to reduce the amount of emissions, as in a very restricted number of stations certain types of sealants and gaskets are responsible for the majority of the leaks. The final conclusion is that with quite simple resources and labour a considerable emission reduction can be reached using the Dutch way of working and technology. The Dutch working method can be easily transferred to other projects.

3 TABLE OF CONTENTS ABSTRACT 1 Introduction 2 Aims and Parties Involved 3 Procedure 4 Experiences and Results 5 Evaluation 6 Conclusions Useful links References Acknowledgements

4 1. Introduction This project Development and Implementation of Natural Gas Leak Detection Systems at the Mosgaz Distribution System, based on Dutch Tested Equipment and Experiences, was funded by the Agency for International Business and Co-operation (EVD) of the Dutch Ministry of Economic Affairs. Through this project, Moscow s gas distribution company, Mosgaz and Dutch partners were able to develop a new leak mitigation program for the gas distribution stations of Mosgaz. For environmental, safety, and cost reasons, natural gas leakage in gas distribution networks is an important issue that has to be managed by the gas industry world-wide. The main component of natural gas is methane (CH 4 ), the second most serious source of greenhouse gases emission next to carbon dioxide (CO 2 ) contributing to global warming and climate change. Therefore it is important that the emission of natural gas is reduced as much as possible, all the more that the weight-equivalent contribution to global warming of natural gas is 23 times higher compared to carbon dioxide. Reduction of natural gas emissions is not only an environmental issue, but it also serves to reduce energy wastage and costs. During the period a project was carried out in Moscow, the capital city of Russia, in which a natural gas leak reduction program for pressure regulation stations was developed and implemented at Mosgaz. Mosgaz is the biggest distribution pipeline network operator in Russia with a gas distribution network of 7,320 km, owned by the Moscow municipality. Mosgaz distributes 29 billion m 3 natural gas annually to 2,500 industrial companies, thermal power stations, 70 district and block heating stations and to 5 million people living in 2 million apartments in the Moscow area. Before the project, Mosgaz had no system in place to systematically detect and repair gas leaks in its distribution system. However, Mosgaz has a safety system for controlling gas leakages, which form a direct risk to people and surrounding area. Gas stations are generally very well ventilated and leakages of a few cubic metres an hour do not affect safety although the amount of gas escaping over a year can be considerable. Even under normal conditions of operation, considerable losses and environmental harm are incurred due to leakage as a result of the deterioration of the components in the pressure regulating stations. The gas regulating stations in use by Mosgaz are shown in tables 1 to 3. Mosgaz is responsible for the maintenance of these stations. Type Station Inlet Pressure Outlet Pressure Number [bar] [bar] District Station District Station District Station District Station Total 396 Table 1: Pressure Ranges of the Gas Regulating Stations in Use by Mosgaz As shown in table 2, the first station was built in The average year of construction is 1987 (the median year is 1994).

5 Construction Year Number Total 396 Table 2: Age of the Gas Regulating Stations in Use by Mosgaz Capacity in 1,000 m 3 /h Number , Total 396 Table 3: Capacity of the Gas Regulating Stations in Use by Mosgaz 2. Aims and Parties Involved The first aim of this project was to transfer technology concerning leakage reduction in gas stations from The Netherlands to Russia. The underlying challenge is to protect the environment by reducing methane emissions. The primary focus of the project was to develop a program for the detection and reduction of leakages in gas regulating stations of Mosgaz, by performing a pilot project and the intensive training of Mosgaz personnel, both in The Netherlands (theoretical) and on the job. Activities were detection, measuring and repairing leaks in a few selected, representative gas distribution stations by establishing advanced identification, classification and quantification of leaks and repair practices. The project should lead to a 90% reduction of leakages in the selected Mosgaz stations, inspiring other Russian companies and institutions. This project was contracted under the umbrella of the 'Memorandum of Understanding on Co-operation in the Area of Energy Efficiency and Renewable Sources of Energy, that has been signed between the Ministry of Industry and Energy (MIE) of the Russian Federation and the Ministry of Economic Affairs of The Netherlands in spring The project was executed by Lighthouse Russia, together with Kiwa Gas Technology and Climate Focus as subcontractors. The principal for this project was the Agency for International Business and Co-operation (EVD) of the Dutch Ministry of Economic Affairs. A memorandum of understanding was signed between EVD and Mosgaz as the recipient in the context of the project, expressing the good intentions between the parties, and describing the formal relations between all parties involved. In table 4 an overview has been given of all participating companies and their principal role. 3. Procedure The location and scope of the pilot project were agreed upon through site visits and meetings between the consortium members. The detection and measuring equipment was ordered, delivered and taken into operation. Mosgaz personnel were trained by means of a study tour in The Netherlands and on the job field training in the detection and measurement of leaks.

6 Ministry of Industry and Energy (MIE) of the Russian Federation Ministry of Economic Affairs of The Netherlands Agency for International Business and Cooperation (EVD) Mosgaz Lighthouse Russia Kiwa Gas Technology Climate Focus Ilma and Graflan Bacharach Power of Decision Power of Decision Sponsor of the Project Project Owner Project Leader Subcontractor, Supplier of Training and Technology Advisor on Joint Implementation Compliancy Suppliers of Sealants and Gaskets Supplier of Gas Leak Rate Flow Measurement Apparatus Table 4: Participating Companies and Their Principal Role in the Project Five selected gas regulating stations were subjected to a leakage check and the amount of leakage was measured. A work plan for repair of the gas leakages was developed, based on the results of the detection and measurement of these gas leakages. After purchasing the repair materials, the repair works were carried out under the supervision of the Dutch specialists from Kiwa Gas Technology. After re-pressurizing the stations, the leak measurements were repeated in order to check the results of repair activities. The leakage reduction was calculated, based on the quantitative leakage measurements before and after leakage repair. In order to have a better idea of the actual leakages in the various gas stations, a number of gas stations (10) were checked for tightness. This action gave a better idea of the amount of leaking natural gas because the stations selected varied strongly in pressure, capacity and age. Five gas regulating stations were selected to be repaired in the pilot project, see table 5. This is a representative selection of all the 396 stations in use by Mosgaz. This selection was based on the number of stations with the same inlet pressure, the age and the capacity of the stations. The total capacity of these five gas distribution stations represents about 4% of the total capacity of all Mosgaz gas regulating stations. Inlet Pressure [bar] Year (Built or Renovated) Capacity [m3/h] Station and Number on List ,000 Krasnodonskaya ,000 Prolomny ,000 Rusakovskaya ,000 Pechatniki ,000 Ljublino-1 Table 5: Selected Stations for the Pilot Project

7 4. Experiences and Results An example of a leakage detection measurement for a valve stem in a selected station is given in figure 1. Figure 1: Example of a Leakage Detection Measurement Working Program In close co-operation with all parties involved, a working program has been drafted and approved. The program included steps like selection of suppliers, risk analysis, identification, classification and quantification of leaks, repair program, training, required results, etc. A very important limiting condition was that the project would be finished on a certain date. Measuring Equipment Before starting the project, Mosgaz possessed no equipment for the measurement of gas leakages. A modern gas detection device, the Hi-flow Sampler, was chosen for the gas leak measurements. This device is currently the only available instrument that measures actual emission rates. For the five selected gas stations all leaks detected which were larger than 1 litre per hour have been quantified using Hi-flow Samplers. Training Programs in The Netherlands and Moscow Personnel from Mosgaz were trained with the help of specific training programs both in The Netherlands and in Moscow. The major part of their training was on site. The training of the Mosgaz personnel consisted of the following three steps: - Study by two groups of Mosgaz delegates during a visit to The Netherlands. The main purpose of the study tour was to transfer knowledge about and to provide insight into the Dutch vision and methods of measurement of the above ground gas distribution infrastructure in The Netherlands. - Training of Mosgaz staff in leak detection, methane emission measurement and leak repair. Two training programs have been drawn up: one for leak detection, classification and quantification, and the other one for leak repair. Kiwa Gas Technology provided the training which consisted of classroom sessions and on the job training in leak detection, methane emission measurement and leak repair technologies.

8 - Representatives of Climate Focus trained Mosgaz personnel in applying a working method for the measurement and repair of gas leaks which complies with the requirements for Joint Implementation projects under the Kyoto Protocol. Leak Measurements In table 6, the number of leaks for each station is shown, classified by component. In total 128 leakages have been detected and subsequently repaired. The average total leakage due to these 128 leaks amounted to 69,313 m 3 natural gas per year. Stem Sealant Threaded Fitting Flange Valve Stem Plug Union Diaphragm Mechanical Total Krasnodonskaya Prolomny Rusakovskaya Pechatniki Lublino Total Table 6: Compounds Needing Repair Table 7 shows the results of the leak measurements by component or sealing component, both for the total leakage (absolute and percentage) and the mean leak rate. Of the leakages 89.8% were found in stem sealants or gaskets, threaded fittings and flanges, causing 96.6% of the total leak rate. Component or Sealing Component Number Total Leak Rate [m 3 /yr] Percentage (%) of Total Leak Rate Mean Leak Rate [m 3 /yr] Stem Sealant 40 40, ,007 Threaded Fitting 52 14, Flange 23 12, Plug 7 1, Union Diaphragm Valve Stem 2 < < 10 Total , Table 7: Leak Rate per Component or Sealing Component

9 During two weeks in the autumn of 2008, all leaks were repaired by trained Mosgaz personnel. Figure 2 shows the instruction of the Mosgaz personnel for the repair of the stem sealants of gate valves. Figure 2: Repair Instruction of Mosgaz Personnel Results of Repairs The results of the repairs are given in table 8. For the three stations Pechatniki 34, Rusakovskaya and Krasnadonskava, only one leak smaller than 1 litre per hour remained in flanges of the gate valve for each station, and a leak in a threaded fitting of a union. The total reduction of natural gas emissions for these three stations was 592 m 3 per year. For Prolomny, twelve leaks were completely stopped, resulting in a leakage reduction of 3,329 m 3 per year. The total emission of natural gas before repair at Ljublino-1 amounted to 65,408 m 3 per year, and after repair to 930 m 3 per year. This means that the gas emission was reduced by 98.6% for this station. Name of Station Leakage Detected [m 3 /yr] After Repair [m 3 /yr] Percentage Reduction Krasnodonskaya % Prolomny 3, % Rusakovskaya % Pechatniki % Ljublino-1 65, % Total 69, % Table 8: Leakage Before and After Repair for the Five Selected Stations Remarks on table 8: - Leakages < 1 litre/h have not been taken into account and have been considered as tight - Remaining leakage due to one defect after repair

10 5. Evaluation of the Project Results of the Project The project was carried out on time and the transfer of Dutch technology has been successful. All parties involved contributed to the project with dedication and enthusiasm. The project had to prove that a considerable reduction of methane would be possible by repairing leakages in stations and the project succeeded in this remit. The training program and the project approach are a good basis for the carrying out of similar projects on a large scale. The initial target of 90% reduction has been amply exceeded. The natural gas emission of the five selected stations was reduced with a total of around 68,000 m 3 annually. It was stated that the five selected stations were representative for the other stations. It is obviously difficult to say that these five stations are a complete representation of all stations in use by Mosgaz, because the stations vary widely in age, pressure and capacity. Nevertheless, assuming that the selection is representative, the total emission of methane of all gas regulating stations in use by Mosgaz can potentially be reduced by about 5 million cubic metres a year. Safety Although some leakages were considerable, safety was not an issue because all leakages found were much lower than 5,000 litres per hour, assuming that all electrical installations comply with ATEX guidelines. Stations are well ventilated according to the regulations and the measured leaking quantities do not give rise to any safety problems in practice. Safety is an important item for Mosgaz, and installations are continuously surveyed on this aspect. Economics and Return on Investment During the project, costs were made for labour and materials, not only for the repairs themselves, but also for training program, travelling etc. Nevertheless, costs for repair are rather high, since the stations will be out of operation during a certain period. If a repair could be carried out together with a major maintenance program, then these costs can be reduced considerably. It will be obvious when gas prices increase that leakage reduction activities will be far more profitable. Although the repair program is not profitable for direct operation, it is very profitable for the environment. In the majority of European countries a trade system in greenhouse gases is in operation, in which CO 2 equivalents are transferred in monetary value. With the new technology, apparatus and materials, Mosgaz now has the skills to implement the program as part of regular business operations. Considering the price of natural gas nowadays, a total reduction of 5 million cubic metres per year represents a value of about yearly. Development of a Joint Implementation Project under the Kyoto Protocol Continuous monitoring of Joint Implementation compliance of all technical interventions in the Mosgaz network was ensured during the project preparation and implementation. Mosgaz personnel are now fully trained to measure and repair leaks in compliance with requirements for a Joint Implementation project. Therefore, a Joint Implementation project could be developed based on the implementation of this pilot project in all the gas distribution stations of Mosgaz. Saving of Energy A loss of about five million cubic metres per year corresponds with the yearly consumption of about customers in The Netherlands, that is to say a small town. The leakage rate found at the stations of Mosgaz may be considered as representative for Eastern Europe. Some distribution companies will perform better but other will perform worse. All things considered it can be estimated that the total amount of energy loss per country due to leaks in gas stations may be about equal to the consumption of a rather big city.

11 Leakage Details Considering the results of leakage measurements it is obvious that a big difference exists in the number of stations and types of components contributing to the total leakage. Almost all leakage is coming from only one station, the contribution of the other stations is rather low in comparison with Ljublino-1 station. Furthermore, it is obvious that only a few components contribute to major leakage: stem sealants, threaded fittings and flanges are the major contributors, whilst plugs, unions, diaphragms, unions fittings, valve and valve stems hardly contribute, see Table 7. The target of this project was to reduce leakage by at least 90%. An unspoken wish was to carry out the repair in such a way that a tightness would be reached of 100%. This objective has almost been fulfilled. By setting a lower target the amount of work can be reduced considerably. Even a leakage reduction of, for example of 70-80% is still acceptable and much better than to leave leaks leaking. With modern gas detection a quick scan can be easily carried out and this will not demand too much time. Further time saving can be achieved by measuring only the critical components (stem sealants, threaded fittings and flanges). By accepting a larger leakage the repair activities can be reduced considerably. In the pilot project leakages of less than 1 litre per hour have been considered as leak tight. If, for example, a leak of 100 litres per hour would be considered as acceptable, the number of leakage points will decrease considerably without a dramatic effect on the total emission reduction. Most countries within Europe accept a certain leakage rate in domestic and industrial pipe work. Most countries consider (existing) pipe work with a leakage of 1 litre per hour as leak tight (In the Netherlands the leak rate considered as leak tight for domestic is 1 l/h, at 1 to 5 l/h the customer will be warned, and over 5 l/h is unacceptable, new pipe work must be absolutely leak tight). According to the European Standard (EN 15001) new gas installations shall be absolutely tight during commission. For the operating phase there are no clear requirements with respect to the leakages allowed. The European Guideline ATEX (explosion safety) starts from the point of view that larger installations produce a leakage of 1 gram natural gas per second (which is about 5 m 3 /h). However, ATEX considers only safety and not energy wastage. It is obvious that it is absolutely preferable to have a 100% gas-tight system, but for success in the short term it is acceptable to make use of the above mentioned considerations. 6. Conclusions The purpose of the project was to develop and implement a natural gas leak reduction program for Mosgaz, based on Dutch tested equipment and experience. The project resulted in a significant reduction of natural gas emissions at the selected gas regulating stations. It is hoped that these results will inspire other companies and institutions, Russian and otherwise. Before the repairs, the annual emissions of natural gas in five selected stations amounted to 69,328 m 3. The project consortium succeeded in reducing these emissions to 930 m 3, which equals a reduction of 98.7% of the original emissions. The success of the project was to a great extent the result of the commitment shown by each consortium member and the excellent co-operation between the consortium members. A selective repair program could help to reduce the amount of emissions, because a very restricted number of components and types of sealants and gaskets are responsible for the major part of the leaks. The project showed that with quite simple resources and labour a considerable emission reduction can be achieved using the Dutch way of working and technology. The Dutch working method is easily transferable to other similar projects.

12 Useful links (ATEX Directive) (EN 15001) References 23 rd World Gas Conference 2006 in Amsterdam Improvement in the Determination of Methane Emissions from Gas Distribution in The Netherlands. (J.B.W. Wikkerink, M.E. Jonker (Kiwa Gas Technology, Apeldoorn, The Netherlands) Acknowledgement The authors would like to thank the Agency for International Business and Co-operation (EVD) of the Dutch Ministry of Economic Affairs for their support in conducting this project. The authors would also like to thank the staff of the following companies involved in the project for their valuable contribution: Mosgaz, Lighthouse Russia, Climate Focus, Ilma, Graflan and Kiwa Gas Technology, in particular Mr. Kippers, Mr. Lock and Mr. van Orizande.