Public announcement on the environmental impact assessment approval for the Zhongtian Hechuang mine water advanced treatment plant project

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Public announcement on the approval of the environmental impact assessment for the Zhongtian Hechuang mine water advanced treatment plant project. Author/Source: Yaha Consulting. Date: 2017-09-27. Clicks: 54. On September 25, 2017, the Ordos Environmental Protection Bureau issued a public announcement regarding its proposed decision on the approval of the environmental impact assessment document for this construction project. Project Name: Zhongtian Hechuang Energy Co., Ltd. Mine Water Advanced Treatment Plant Project
Location of Construction: Wushen Banner
Constructor: Zhongtian Hechuang Energy Co., Ltd.
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Environmental Impact Assessment Agency: Inner Mongolia Baisiba Environmental Technology Consulting Co., Ltd.
Project Overview: The advanced water treatment station is located in the northeastern part of the plant area of the Zhongtian Hechuang Ordos Coal Deep Processing Demonstration Project, within the Tuk Industrial Park of the Sulihe Economic Development Zone in Wushen Banner ； The mine water pretreatment station is located at the northwest corner of the Hulusu mining area’s industrial site ； The three reservoirs are located 400 meters south of the Mengqing Mine industrial site ； The newly built raw water pipeline is located in Tuk Town, Wushen Banner, and runs roughly in a north-south direction. The depth treatment plant has a processing capacity of 3,000 m3/h (with space reserved for an additional 1,500 m3/h of capacity); it is used to treat some of the wastewater from the Mengkeqing and Muducaideng mines, as well as all the wastewater from the Hulusu mine. The treated water is then used as process water for the Zhongtian Hechuang Ordos Coal Deep Processing Demonstration Project ； Expand the cucurbitacin mine water pretreatment station by increasing the capacity of the existing facility from 1050 m3/h to 1650 m3/h, which means constructing an additional pretreatment unit with a capacity of 600 m3/h (the third-phase mine water treatment station) ； A 6.7 km water transmission pipeline is to be constructed as part of this project. The water transmission pipelines for this project are divided into two sections: 4.5 km of new pipeline will be built from the Hulusu Mine area to the advanced treatment station, while most of the pipelines connecting the Menkeqing Mine and Muduchaideng Mine to the advanced treatment station make use of the existing pipelines from the \"China Coal Energy Ordos Energy Chemical Industry Base Coal Mine Underground Drainage Reuse Project\". At the Jingwei First Road intersection, a T-junction is installed to branch off one water transmission pipeline that connects to the advanced treatment station of this project; the length of the newly built section is 2.2 km ； The three reservoirs at the Menkeqing mine were renovated by making use of existing structures. The deep water treatment plant for this project employs a process of \"desalination + secondary concentration + evaporation crystallization\". The quality of the treated water meets the standards specified in \"Reuse of Urban Wastewater – Water Quality for Industrial Use\" (GB/T 19923-2005), and it is used as process water for the \"Zhongtian Hechuang Ordos Deep Coal Processing Demonstration Project – Methanol to Olefins\". The third phase of the new cucurbitacin mine water pretreatment plant adopts a \"pre-sedimentation + adjustment + high-efficiency sedimentation\" process, with the treated water being sent to the advanced water treatment plant of this project. The existing reservoir will be reinforced, with embankments constructed around it ； The bottom of the reservoir is lined with an HDPE polyethylene impermeable geomembrane 1.0 mm thick; the bottom of the reservoir is welded to the impermeable geomembrane of the embankment using heat welding, and a protective layer is placed over the geomembrane. The deep water treatment station covers an area of 0.0465 km2, the cucurbitacin mine water pretreatment station covers 0.0039 km2, and the reservoir covers 0.2998 km2. All these facilities are located within the existing factory and mine areas, with no additional land use ； The raw water pipeline requires an additional land area of 0.027 km2, which is a temporary land use project. This project adds 76 new staff members, all of whom are assigned to the advanced treatment station. The total investment for the project is 702.2992 million yuan, all of which are allocated to environmental protection initiatives. Main environmental impacts and strategies and measures to prevent or mitigate adverse environmental impacts. Exhaust gases: 1. Dry dust – The main sources of air pollution in this project are the slight amounts of dust generated during the crystallization and drying stages of sodium sulfate, sodium chloride, and various other salts in the evaporation and crystallization process. For the crystalline drying of sodium sulfate and sodium chloride in this project, tray dryers are used, while a rake dryer is employed for the spray drying stage of mixed salts. One set of bag filters is installed for each of the three dryers. Based on similar dryers, the dust generation concentration is 2600 mg/m3; the accompanying fan has a capacity of 2000 m3/h. Assuming a dust removal efficiency of 99% for the bag filters, the dust emission concentration is 26 mg/m3, resulting in an annual dust emission volume of 0.456 tons. The crystalline dust, after dust removal, is discharged through a 15-m-high exhaust stack; both the dust emission concentration and the emission rate meet the requirements of the secondary standards for new pollution sources specified in the \"Comprehensive Emission Standards for Air Pollutants\" (GB16297-1996). 2. Uncontrolled acid mist from storage tanks: This project includes 3 hydrochloric acid storage tanks and 1 sulfuric acid storage tank. When the acid arrives at the site, it is transferred from the truck’s discharge port to the storage tank’s inlet; the acid inside the tanks is connected to the dispensing equipment through pipes, and everything remains in a sealed state. However, during the process of feeding and storing the acid, a small amount of acid mist may escape from the exhaust ports. To prevent this, acid mist collectors have been installed at these ports, using alkalis to neutralize the acid mist and thus avoid its release. Both HCl and sulfuric acid mist meet the concentration limit requirements outside the perimeter as specified in the \"Integrated Emission Standards for Air Pollutants\" (GB16297-1996). Wastewater: (1) Advanced wastewater treatment plant – The wastewater generated by this plant comes mainly from the backwash water from various processes such as V-type filters, ultrafiltration units, and secondary concentration processes, as well as from the sludge pressing water from sludge collection tanks and condensate water. The volume of this wastewater is 703.15 m3/h. Among them, the backwash water from V-type filters and ultrafiltration units amounts to 469 m3/h, while the sludge pressurized water after sedimentation in universities amounts to 39 m3/h; this water is sent back to the high-efficiency sedimentation tank for further treatment and is not discharged outside ； The backwash water from each stage in the secondary concentration process amounts to 55 m3/h, and it is returned to the contact clarifier in the secondary concentration process for further treatment ； During the various stages of the evaporation and crystallization process, 138.59 m3/h of condensate water is generated, which is sent back to the high-efficiency reverse osmosis unit in the secondary concentration process. Meanwhile, 1.56 m3/h of water produced by ultrafiltration and nanofiltration processes is sent back to the catalytic oxidation stage for further treatment. The domestic wastewater generated at the advanced treatment station amounts to 0.152 m3/h. This wastewater is treated by the existing wastewater treatment plant within the site of the Zhongtian Hechuang Ordos Coal Deep Processing Demonstration Project, and the treated water is used for watering the plants on the site. This project treats 3,000 m3/h of mine water, with a output of 2,995.22 m3/h, meeting the standards specified in \"Reuse of Urban Wastewater – Water Quality for Industrial Use\" (GB/T 19923-2005); the treated water is used as process water for the \"Zhongtian Hechuang Ordos Advanced Coal Processing Demonstration Project – Methanol to Olefins\". (2) Trichosanthin pretreatment station: The trichosanthin pretreatment station generates 7.7 m3/h of sludge filter water, which is sent back to the pre-sedimentation tank for further treatment. (3) Groundwater prediction and well layout: According to the groundwater prediction, under abnormal operating conditions, the maximum distance that pollutants from the deep-water treatment plant, water transmission pipelines, and the Hulusu mine water treatment plant can travel in the groundwater is 399 meters. There are no groundwater protection targets such as drinking water wells within this polluted area; therefore, the impact on groundwater is minimal. Moreover, the nearest distance between this project and the Chagan Naoer water source is 4.29 km. It can be concluded that the construction of this project will have no impact on the Chagan Naoer water source. In accordance with the \"Technical Specifications for Groundwater Environment Monitoring\" HJ/T164-2004, it is planned to make use of the existing monitoring wells throughout the Zhongtian Hechuang factory area. The northern evaluation area for groundwater includes the deep water treatment plant, the raw water transmission pipelines, and the Hulu Su mineral water treatment plant. It is planned to install 4 groundwater monitoring wells there: 2 will be based on existing monitoring wells, while 2 will be new ones. The depth of each of these new monitoring wells is 15 meters, with the monitoring layer being the phreatic aquifer. The southern evaluation area for groundwater includes reservoirs, and it is planned to install 4 monitoring wells. Of these, 1 will utilize an existing monitoring well, while 3 will be new wells. The depth of each of the new wells will be 10 meters, with the monitoring layer being the phreatic aquifer. The groundwater monitoring parameters include: K+, Na+, Ca2+, Mg2+, Cl-, SO42-, CO32-, HCO3-, pH, ammonia nitrogen, nitrates, nitrites, permanganate index, total hardness, total dissolved solids, volatile phenols, fluoride, cyanide, iron, manganese, mercury, arsenic, cadmium, hexavalent chromium, lead, total bacterial count, and total coliforms. These parameters are used to assess the quality of groundwater in the area. While monitoring water quality, groundwater levels are also monitored simultaneously. The control well is monitored once per year during the dry season, while the other pollution monitoring wells are monitored once per year in odd-months, resulting in 6 monitoring sessions per year. Noise: During the operation of the project, the main sources of noise are air compressors, fans, mixers, and various pumps. The maximum sound intensity generated by the noise-producing equipment in the project’s advanced treatment station is 90 dB(A). All types of noise-generating equipment in this project are installed within sound-insulated buildings, and the pumps are placed in semi-underground structures. The sound-insulating properties of these semi-underground reinforced concrete enclosures are fully utilized; in addition, noise reduction measures such as shock absorption and flexible connections are employed, resulting in outdoor noise levels of 60–75 dB(A). According to the predictive analysis, the predicted values of the noise generated by the various equipment at the advanced treatment station for the daytime noise levels at the boundary of the Zhongtian Hechuang Coal Deep Processing Demonstration Project site range from 55.1 to 56.8 dB(A), while the predicted nighttime noise levels range from 47.02 to 48.91 dB(A). These values meet the standard limits specified for Zone 3 in the \"Emission Standards for Environmental Noise at Industrial Enterprise Boundaries\" (GB12348-2008) ； The predicted values of the noise generated by the various equipment at the Hulusu Mine Water Pretreatment Station (Phase III) for the overall noise level at the boundary of this station during daytime range from 54.5 to 56.38 dB(A), while the predicted nighttime noise levels range from 47.60 to 52.33 dB(A). These values meet the standard limits specified for Class 2 areas in the \"Emission Standards for Environmental Noise at the Boundaries of Industrial Enterprises\" (GB12348-2008). Solid waste: (1) Sludge from the desalination process in the advanced treatment plant, as well as the sludge from the sludge thickening tank after the high-efficiency sedimentation tank. The amount of such sludge generated is 4.01 tons per day (1,463.65 tons per year). It is treated as Category II solid waste under general industrial solid waste categories and is disposed of by landfilling it at the waste dump site in the Tuk Industrial Project area. (2) Sludge from secondary concentration at the advanced treatment plant: The amount of sludge generated in the sludge concentration tank after the contact tank is 8.763 t/d (3198.5 t/a). This sludge constitutes general industrial solid waste, and it is disposed of as Category II solid waste under general industrial solid wastes, by being buried in the landfill located in the Tuk Industrial Project area. (3) Mixed salt cakes from the advanced treatment station: The amount of salt cakes generated is 3.84 t/day (1,401.6 t/year). The main components of these salt cakes may include sodium salts, potassium salts, calcium, magnesium, and other metal substances. These mixed salt cakes constitute general industrial solid waste, and should be disposed of as Category II industrial solid waste. They are temporarily stored in the temporary storage area for salt cakes within the desalination workshop, before being transported to the landfill site in the Tuk Industrial Project area for disposal. (4) Waste filter membranes from advanced treatment plants: The waste filter membranes in this project are primarily those from the ultrafiltration systems in advanced water treatment plants; they need to be replaced every three years, with a replacement volume of 45 tons per 3 years ； The reverse osmosis membranes in the reverse osmosis system of the advanced water treatment plant are replaced every three years, with a replacement volume of 20 tons per 3 years ； The reverse osmosis membranes of the high-efficiency reverse osmosis system treated with concentrated brine are replaced every three years, with a replacement amount of 15 t per 3 years. Therefore, the amount of waste filter membranes generated is 75 t/3 years, which is collected and disposed of by the manufacturer. (5) Evaporated crystalline salts: The evaporative crystallization workshop in this project produces 6.24 t/h of Na2SO4 evaporated crystalline salts (54,662.4 t/year) and 0.88 t/h of NaCl evaporated crystalline salts (7,708.8 t/year) through various crystallization processes, which are sold as products. (6) Sludge from cucurbitacin pretreatment station: The sludge generated at the cucurbitacin pretreatment station mainly comes from the pre-sedimentation tanks and high-efficiency sedimentation tanks, with a production volume of 88.65 t/day (32,357 t/year). It constitutes general industrial solid waste, and is disposed of as Category II industrial solid waste, being sent to the landfill in the Tuk Industrial Project area for burial. (7) Domestic waste: The amount of domestic waste generated in this project is approximately 13.87 tons per year. Waste bins are installed on site for collection, and the local sanitation department is entrusted to handle it accordingly. Ecology: This project involves the advanced treatment and reuse of mine water. The wastewater from mines, after undergoing advanced treatment, is reused as process water in the coal deep-processing demonstration project site operated by Zhongtian Hechuang Energy Co., Ltd., thereby effectively addressing the ecological damage caused by the current discharge of mine water. Mine drainage consists of water contained in the coal seams; it has little impact on the phreatic layer and does not affect the growth of surface vegetation. During pipeline construction, strict control is exercised over the construction area; the width of these areas on both sides is kept within 6 meters. At the beginning of pipeline construction, the topsoil is removed and piled up in designated locations within the construction area, where it is then covered. After the pipeline construction is completed, soil is spread along the route and vegetation is planted. Most of the pipelines in this project are located within the Tuk project area and run along roads; the landscaping requirements are such that the vegetation matches that already present in the area, with a combination of trees, shrubs, and herbs to create a harmonious landscape. The total area dedicated to landscaping is 1200 m2, with a vegetation survival rate of over 90%. (VI) Risk Prevention: The hazardous chemicals involved in this project include sodium hypochlorite, hydrochloric acid, sodium hydroxide, sodium sulfite, sodium bisulfite, sulfuric acid, etc. There are no major sources of danger. In accordance with the risk prevention measures proposed in the Report, this project implements effective risk prevention strategies in areas such as process technology design, safe control of hazardous materials and project management, as well as water environment risks. Two accident tanks with a capacity of 2,000 m3 each have been installed at the advanced treatment station; meanwhile, in the event of an accident, the water from the Munkyeong and Muducheiden mines can be temporarily stored in these tanks. The two 2,000 m3 accident tanks are sufficient to handle the wastewater generated by the Hulusu mine over a 2-hour period in case of an accident. The cucurbitacin pretreatment station is equipped with one 20,003 accident tank, which can accommodate the water volume required for 1 hour in the event of an accident in the raw water pipeline from the cucurbitacin station to the advanced treatment station. It can meet the project requirements.