RZD, LokoTech and ST discussed with the public a project to eliminate the ‘phenol lake’
On October 14, online conference on the ‘phenol lake’ issue took place in Ulan-Ude city. This lake contains 70 tons of highly hazardous wastes of locomotive car repair plant (LVRP). The subject of discussion is the project of liquidation of the old sludge pond, which was developed by CJSC Safe Technologies.
The core of the plan is pyrolysis plant, which is to be delivered to the site. The process of waste utilization will take years. At the same time, a stage-by-stage final post-cleaning and land reclamation will be performed.
At the public hearing in September, the project received a positive evaluation from the professional scientific community, including independent experts of the State Environmental Expertise (SEE) and the majority of citizens present. The next step was to submit project documentation for the State Environmental Expert Review to assess its safety for the environment and public health. However, at the end of the hearings, the public had some questions: the citizens of Ulan-Ude were concerned that thermal waste processing in the geographical center of the city would result in extremely hazardous emissions to the atmosphere. Another question — why choosing pyrolysis technology among many other methods.
To answer these and other questions, the project commissioners (Russian Railways, LokoTech and Zheldorremmash) and representatives of CJSC ST contacted the interested public from the building of the Government of the Republic of Buryatia. The event was moderated by the Ministry of Natural Resources of the Republic of Buryatia and was quite open in its nature: anyone could ask a question and express their opinion. All comments and objections will be considered when finalizing the EIA section before submitting it to the SEE.
PYROLYSIS IS NOT INCINERATION
‘Burning the poisonous lake in the city center is unacceptable’, – that was the main protest of citizens. Experts explained that pyrolysis is a process of decomposition of organic raw materials in special air tight reactors in an oxygen-free environment, while waste incineration is an oxidation and it is conducted in an environment with excess air.
Incineration implies complete destruction of waste, pyrolysis — their processing. In addition, in the case of pyrolysis, emissions into the air are much lower, which in pre-project studies was assessed as a key criterion for the choice of technology.
The pyrolysis technology is in many respects similar to the technologies used in oil refining and is not related to incinerators in their classical sense. The waste consists of coal tar mainly and there are no halogen atoms in it, so the formation of dioxins is excluded.
Thermal destruction plants will be equipped with multistage gas purification systems preventing harmful emissions into the atmosphere. The environmental impact will be controlled and monitored with the help of flue gas monitoring instruments.
BIASED TECHNOLOGY SELECTION
‘There are many other, more promising technologies. The customer has chosen the least expensive way for itself’.
The project has been working on for over two years. At the first stage, complex engineering researches have been carried out — actual data on the lake content composition have been obtained. At the second stage of designing main technological solutions were adopted.
‘We studied various technologies that we received during the whole design period as proposals to our customer’, — comments Olesya Epinina, Head of Environmental Department of CJSC ST and developer of EIA section of project documentation. — ‘More than twenty processing methodologies were considered, including the currently voiced bioprocessing, plasma gasification, supercritical water oxidation. And on the basis of the conclusions four process diagrams were developed, which have already been assessed in detail as possible for implementation.
The first criterion, the most important one, is the environmental impact. The key point, prescribed in the design specification — the technology must necessarily be the best available techniques (BAT), be included in the handbooks, which were developed under the auspices of the Ministry of Industry and Trade by the best Russian experts in decontamination and waste management. Most of the technologies could not be applied due to the fact that they have not been tested in the Russian Federation and therefore are not classified as BAT’.
Processing at pyrolysis units is included into BAT list according to the ITS 9-2015 reference book (approved by Rosstandart Order No. 1579 of December 15, 2015). Inclusion of the technology in the reference book means that it has already been evaluated by experts, tested and applied in practice. Under the conditions of the significance of the «phenol lake» facility, it is inappropriate to apply insufficiently developed methods due to the risks of possible accidents and related negative consequences, as well as due to limited terms of reclamation and equipment delivery. Other technologies require a long period of research and development, including the period of pilot testing, and do not guarantee a positive result. Also, new technologies require a long process of inclusion in the relevant directories, registers, etc.
‘An additional control element is a positive conclusion of the state environmental expertise on technology’, added Olesya Epinina.
Pyrolysis provides the maximum possible economic benefit, in the situation with the ‘phenol lake’ is an opportunity to maximize the resource potential of waste. In the process, liquid fuel and electricity will be produced at the facility, as well as dry mineral residue — technical soil, which will be certified as products for backfilling into the ‘lake’ pits.
In response to the widespread belief that waste components can be used as cost-effective raw materials, for example, in the petrochemical industry, Konstantin Ladygin objected:
‘Receiving raw materials for sale is currently complicated by legislation. Deposited for many years coal tar, underwent secondary pollution, physical and chemical transformations, it was mixed with the ground, etc. changed its composition and aggregate state, unevenly distributed over the area of the facility and Its processing is simply unprofitable and incomparable with the stipulated liquidation period’.
IMPACT ON THE ATMOSPHERE
The EIA section of the design documentation includes calculations of the impact on atmospheric air, considering the modes and periods of operation of equipment and vehicles, the location of the facility relative to residential areas, as well as taking into account the existing background air pollution in the area.
The situation around the ‘lake’ area is already unfavorable due to the emissions from Heating and power plant -1, and the project has taken this into account. A decision was made to develop special measures for reclamation during the period of unfavorable weather conditions up to a complete halt of the recultivation process for the entire winter season, if necessary.
According to the dispersion calculations performed, the maximum permissible concentrations in the air will not be exceeded for all substances emitted during reclamation, while according to some estimates the current impact of the facility on the air by the phenol already now exceeds the established normative maximum permissible concentration.
It should be noted that the total volume of emissions from all pyrolysis equipment during 2 year reclamation period, as compared to emissions from CHP-1 power station will be hundreds of times less due to scale difference of processes — and will be mainly represented by substances of 3-4 hazard classes. Nitrogen dioxide, carbon monoxide and sulfur dioxide are less toxic in comparison with the current emissions from the surface of the ‘lake’ (phenol — substance of hazard class 2).
‘There will be emission monitoring equipment installed, which will also measure the level of air pollution in nearby residential buildings, snow cover monitoring and control of soil and land resources, surface and groundwater’, — says Konstantin Ladygin.
The pyrolysis equipment is also equipped with a gas purification system based on catalytic oxidation of volatile organic compounds. This is the latest innovation of Safe Technologies CJSC, which was implemented with the support of the RF Ministry of Education and Science.
At present, Zheldorremash consistently reduces emissions from the LVRP itself, so the negative impact of the reclamation equipment will be proportionate to emissions from other shops.
THE ‘LAKE’ NEEDS TO BE REMOVED AND ELIMINATED OUTSIDE THE CITY LIMITS
Some of the representatives insisted that all the contents of the «lake» should be taken out of the city and already there they were engaged in its liquidation. For a number of reasons, such an event threatens to cause even greater environmental damage.
Indeed, there is good international practice of installing incinerators within city limits, but there are no examples of sites similar to the ‘phenol lake’ in the city center. The proposed solution is based on calculations and not on some guess.
‘100 years ago, there were no settlements around this object. Today, this industrial zone is overgrown with buildings and has become the center of the city’, — said Peter Potapov, head of the Department of Health, Safety and Environmental Control of JSC Russian Railways.
It is dangerous to take the lake contents from its area, and there is no need to do this. Expert opinion was expressed by L.B. Kislitsyna, who participated in research and monitoring of the ‘phenol lake’ object for more than 25 years as the Chief Hydrogeologist of JSC Selengeo:
‘When the gas generation plant was still operating and this huge sludge pit was created, groundwater pollution was monitored. This section was chosen correctly because under it there are Lower Cretaceous dense deposits — argillites. Pollution penetration would have been minimal if it had not been for the section of alluvial-proluvial sediments area along which groundwater flows.
When they say that it is necessary to dig up to 200 meters, in terms of hydrogeology, it is absolutely impossible. Argillite-like sediments do not allow penetration deep enough. We studied the resin content of contaminants — their phenolic component. We studied the soils that lie under these resins and groundwater contamination. It was found that soils are poorly or moderately polluted. But the pollution moved towards groundwater. Until now the pollution did not advance to Uda or reached the Lazovsky field. But now, as a matter of urgency, we need to eliminate this sump and eliminate it on the spot without moving the polluting components somewhere. I wrote about pyrolysis back in 2000s; at that time, the method existed as one of the best ones’.
Konstantin Ladygin, managing partner of CJSC Safe Technologies, comments:
’20 meters is enough, blocking at this point will provide the conditions that are required. In this way we will meet all the requirements of environmental legislation and keep the area that can be used in some social projects’.
The conference resulted in a clarification of all related issues. At present, the project is being prepared for submission to the State Environmental Expert Review, where the Government of the Republic of Buryatia invited experts who expressed their concerns at the conference. As it was specified earlier, the voiced recommendations will be considered in the modification of the utilization project.