The Defense of the Evaporation Ponds

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The Battle to Save the Evaporation Ponds: Not long ago, a small set of evaporation ponds not only damaged the reputation of coal-to-gas projects in the northwest region, but also brought shame to the entire coal chemical industry. It was only at this time that people realized that not only coal-to-gas projects requiring investments in the tens of billions, but also the entire coal chemical industry, with investments in the hundreds of billions, had previously lacked any regulatory documents regarding the design, construction, and operation of evaporation ponds; moreover, there were no evaporation ponds that were operating properly. It was only after repeated incidents occurred in evaporation ponds that, on May 9, 2014, the General Office of the Inner Mongolia Autonomous Region hastily issued local guidelines for evaporation ponds — the \"Notice on Issuing the Guidelines\" (Document No. Neizhengbanfa 38). Some insightful professionals in the industry have begun to reflect on the need to establish **standards for evaporation ponds as soon as possible, in order to bring the design, construction, operation, and management of such ponds under standardized guidelines. But who will do this? What exactly should be done? In our country, the overall design of most coal chemical projects is carried out by large domestic petroleum and chemical engineering design institutes, whereas evaporation ponds are considered a supporting specialty within these institutes and do not receive much attention. Those in water supply and drainage say it falls under the environmental engineering field; those in environmental engineering claim it belongs to the civil engineering field, while those in civil engineering consider it part of the general planning field. Engineering design firms specializing in the chemical industry have always focused their efforts on more sophisticated aspects, such as gasifiers, and simply do not bother wasting time on evaporation ponds that involve little technical complexity. When some professional design firms undertake the design of coal chemical projects, the task related to evaporation ponds is not so much subcontracted as it is simply abandoned. As **environmental regulations become stricter, evaporation ponds, with their low profits and heavy responsibilities, make many design firms avoid them altogether, not even wanting to consider them. Now the evaporation ponds have caused big problems, and only now has everyone realized that establishing standard guidelines for these small evaporation ponds is indeed a tricky task. First, the reference is unknown. Evaporation ponds are not a specialized aspect of the chemical industry; they are an import. As for where it originated from, there are various opinions. Some say that evaporation ponds first appeared in the salt-drying process of the salt-making industry. However, seawater salt production has been practiced in China for thousands of years, and due to differences in region, seawater quality, and other factors, it is still not possible to establish unified design standards to this day. Some say it comes from the nuclear industry, while others say it comes from the waste management sector. Secondly, it’s hard to please everyone. In essence, setting standards for evaporation ponds is nothing other than establishing constraints for coal chemical enterprises themselves. It is a painful process of self-revolution. The main function of an evaporation pond should be to treat concentrated brine; other pollutants in the feedwater, such as COD and oils, must be reduced to levels that do not affect the evaporation process. But what level is appropriate to set? What is the appropriate salt concentration of the incoming water? Setting it too high is pointless; setting it too low causes companies to complain loudly, claiming that it cannot be achieved. As a result, not only is it time-consuming and laborious, but it also annoys people – who would want to do that? There are indeed those who are willing. As early as the end of 2012, the Environmental Protection Design Committee of the China Petroleum and Chemical Exploration and Design Association formally applied to the Standardization Committee of the **Energy Administration to take the lead in drafting the \"Design Code for Concentrated Brine Evaporation Ponds in the Coal-Based Fuel Industry\" (hereinafter referred to as the \"Code\"). On June 8, 2013, the **Energy Bureau approved, via Document No. Guoneng Keji 235, that the Environmental Protection Design Committee of the China Petroleum and Chemical Industry Survey and Design Association take the lead in forming a drafting team together with China Tianchen Engineering Co., Ltd. and Beijing Xuanang Environmental Protection Technology Co., Ltd., to serve as the main drafters of the standards for evaporation ponds. The design specifications for evaporation ponds are divided into two main categories: the standards for the inflow of concentrated brine and the construction standards for evaporation ponds. Since there were no standards for brine evaporation ponds in the coal chemical industry in China before, the compilation team had to draw on relevant standards from industries such as the hazardous waste sector, the general solid waste sector, and the water resources sector (dam construction, reservoirs), taking the best practices from various sources. Gradually, an idea came to mind. The compilation team first set requirements for the water quality of the water entering the evaporation ponds, strictly specifying the limits for pollutants other than inorganic salts in this water, and stipulating that untreated sewage is prohibited from entering the evaporation ponds. The process design draws on the experience of seawater salt production, dividing the evaporation ponds into four functional zones based on their roles: a regulation zone, an evaporation zone, a crystallization zone, and a dried salt zone. The compilation team also proposed that the design of evaporation ponds should be based on parameters such as the annual water inflow volume of the project, the salt concentration and composition of the incoming water, as well as local weather conditions. Evaporation ponds must not only meet the requirements for evaporation rate to ensure effective evaporation but also take into account storage capacity, as well as factors such as wave prevention, sand control, and salt removal. In March 2014, the draft of the Standards was essentially completed. The compilation team held several seminars within the industry, and also outlined the concepts behind the design standards for evaporation ponds that were being developed. These concepts were posted online, as well as communicated to companies in the coal chemical industry through text messages and other means to gather feedback. In May 2014, the draft of the \"Specifications\" was placed on the table of a review meeting attended by professional design institutes such as the Petroleum and Chemical Industry Planning Institute, the China Institute of Water Resources and Hydropower Research, China Global Engineering Corporation, Donghua Engineering Technology Co., Ltd., and Zhonglan Lianhai Design and Research Institute, as well as some coal chemical enterprises. As expected, everyone first expressed support for formulating standards for evaporation ponds to promote industry development, but then things turned into a complete mess. All owners feel that the standard requirements are too high, difficult to implement technically, and unacceptable in terms of investment. In particular, there are significant differences on two issues: first, what kind of water can enter the evaporation ponds. Only concentrated brine can enter the evaporation ponds; other pollutants should be removed as much as possible using existing environmental protection technologies in the early stages of the process, and there is no disagreement on this point. But to what extent is it appropriate? Treating wastewater from coal chemical industries is very difficult; to remove all pollutants would require building another facility for advanced wastewater purification, and in such cases it is better to opt for evaporation or incineration methods. Second is to determine just how effective evaporation ponds are. Some people remain optimistic about the evaporation effects in the northwest region, arguing that since the salt-making industry can produce dry salt in such humid coastal areas, it should be even easier to do so in the drier northwest region. However, some people believe that the northwest region has a short frost-free period and low temperatures; as a result, evaporation ponds serve little purpose during winter, and while they are somewhat effective in summer, precipitation increases, resulting in low overall evaporation rates. Moreover, they require a large amount of land, making them uneconomical – it’s better not to use them at all. Every opinion must be heard, and every opinion must be considered. But one thing the planning team insisted on is that evaporation ponds represent a very large and excellent market. Evaporation ponds play roles in the production safety and environmental protection of coal chemical enterprises that have not yet been recognized by people at present. The key to this market is regulation. The establishment of standards for evaporation ponds is directly related to the development of the coal chemical industry. The drafting team decided to stick to the original intention of establishing high standards for evaporation pond specifications, and on this basis, revised the draft for comments. …… At the end of February this year, the revised draft of the \"Specifications\" was submitted to the Energy Bureau for feedback and received approval, with requests for further revisions. At present, the drafting team is working urgently to make further revisions to the standards and intends to submit them as quickly as possible. Perhaps in not too long, evaporation ponds will have an “ID card”. I wonder if readers have noticed that there is only one company in the compilation team: Beijing Xuanang Environmental Protection Technology Co., Ltd. This private enterprise initially focused on the treatment of municipal solid waste, with its core expertise lying in leak prevention. “After the figure of 4 trillion was mentioned, the coal chemical industry became very popular. They seized this opportunity and got involved in this field, focusing on the evaporation ponds that others considered unimportant; soon they became the most professional company in this area. They are responsible for the evaporation ponds of projects such as the Datang Keqi coal-to-gas project with a capacity of 1.6 billion cubic meters per year, the Xinjiang Yitai Ili coal-to-oil project with a capacity of 1 million tons per year, and the China Coal Ordos Energy Project. But they also suffer greatly from the lack of standards in evaporation ponds. The cost of an evaporation pond for a coal chemical enterprise is generally over 100 million yuan, but the winning bid price can even be as low as 60% of that amount. The consequence of the lack of standards is that companies will lower the construction standards as much as possible, ultimately forcing the evaporation ponds to bear all the negative effects of chaotic competition and low prices. The health of the market is closely related to the survival and development of enterprises. So, they volunteered to do something to defend the evaporation ponds. When an industry faces difficulties, there are always genuine companies that step forward to take action. This is when the progress of the industry begins. During the process of drafting the Standards, someone called this company and said that projects involving evaporation ponds would not be approved at present; when would the standards be issued? (Source: China Coal Chemical Industry, Author: Xie Xiangning)