The serious poisoning incident on \"10·18\" at Runheng Chemical Co., Ltd., Guangrao County, Dongying City, Shandong Province

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Source: China Chemical Safety Association. Added on: 2016-12-26 19:32:51. Views: 105. I. Accident Investigation and Analysis (I) Overview of the Accident 1. Brief Introduction to the Accident At 4:26 a.m. on October 18, 2013, a material leakage accident occurred in the pharmaceutical intermediate production workshop of Guangrao Runheng Chemical Co., Ltd., located in Chen Guan Township, Guangrao County. The accident resulted in 3 people being poisoned, who died despite efforts to save them, with direct economic losses amounting to approximately 2.706 million yuan. 2. Cause analysis: (1) Direct cause – Zhang, the operator at the fluorination station, violated safety procedures by failing to wear the necessary personal protective equipment. While the fluorination tank was under pressure, he used pipe wrenches to tighten the valve covers of the shut-off valves that were already closed, which caused excessive stress on the threads connecting these valves and led to structural instability (thread failure). As a result, toxic materials containing hydrogen fluoride were released. (2) Indirect causes ① Runheng Company 1) Illegal production. Failure to comply with legal procedures for obtaining permits related to work safety, environmental protection, and fire safety; illegal production of hazardous chemicals; illegal purchase of the highly toxic hazardous chemical chlorine; illegal use of unregistered pressure vessels ； Refused to comply with the production halt orders issued by relevant authorities and resumed production without permission. 2) Lack of safety production management systems. The work safety responsibility system and safety management rules and regulations do not align with the company’s actual circumstances, nor have they been officially promulgated; furthermore, the safety operating procedures are incomplete. 3) Lacks basic safety production conditions. Safety training and education are inadequate; the safety competence of employees is poor, and their safety awareness is weak. Key responsible persons as well as those engaged in special types of work are working without the necessary certifications ； Inadequate equipment management and untimely maintenance ； The workshop is not equipped with toxic gas detection and alarm devices, nor are there any safety warning signs for hazardous chemicals; the conditions for safe production do not meet the standards. ②Regulatory authorities: 1) The Chenguan Township Party Committee has failed to carry out its duties related to cracking down on illegal activities and rectifying violations effectively; safety supervision is inadequate, and hazard inspections are not thorough enough. Failing to carry out earnestly the tasks related to cracking down on illegal activities and addressing safety hazards in accordance with the requirements set out in the \"Notice from the People’s Government Office of Guangrao County on Issuing the Implementation Plan for Special Actions to Address Illegal Activities in the Hazardous Chemicals Sector\" (Guangzhengban Zi [2013] No. 37); there was inadequate supervision over the enterprises’ long-standing illegal production and operation activities, and these enterprises were not shut down in accordance with the law. Guidance, supervision, and inspection of enterprises were not carried out in strict accordance with the requirements of territorial management and shared responsibilities among Party and government agencies; insufficient guidance, supervision, and oversight were provided regarding Runheng Company’s work in ensuring safe production. Since 2008, various relevant agencies in Chenguan Township have conducted multiple inspections at Runheng Chemical Company, failing to ensure that the company obtained the necessary safety production permits and that environmental impact assessments were properly carried out. 2) The Work Safety Supervision Bureau of Guangrao County, as the agency responsible for comprehensive supervision of work safety in the county as well as oversight of the hazardous chemicals industry, failed to guide, coordinate, and urge relevant functional departments to fulfill their responsibilities in work safety management. It also failed to organize effectively the special campaigns aimed at cracking down on illegal activities and ensuring work safety in the county, and took no further action regarding companies that refused to comply with orders to suspend production. Inspections of enterprises were carried out carelessly and perfunctorily; the renovation and expansion projects undertaken by enterprises this year were not detected in a timely manner. There was insufficient enforcement and inappropriate measures taken regarding enterprises that operated without a safety production license for hazardous chemicals and engaged in illegal production activities; follow-up supervision and rectification efforts were also inadequate. 3) The Guangrao County Quality and Technical Supervision Bureau, as the department responsible for overseeing the safety of special equipment in its jurisdiction, failed to fulfill its duties related to the supervision of such equipment in accordance with relevant laws and regulations. It also failed to carry out thorough inspections and rectifications of potential hazards as required by the overall plan for combating illegal activities and violations throughout the county. During the inspection, it was found that no pressure vessels directly connected to the valve involved in the accident were unregistered, and such pressure vessels were not subject to supervision. Regarding Runheng Company, there were unlicensed personnel operating special equipment, and the safety operating procedures for special equipment were inadequate; efforts to urge corrective actions were ineffective. 4) The Chenguan Police Station of Guangrao County Public Security Bureau failed to conduct adequate inspections for potential hazards related to highly toxic hazardous chemicals in its jurisdiction, and failed to detect or address illegal activities such as Runheng Company’s unlawful procurement, use, and storage of such hazardous chemicals. 5) The people’s government of Guangrao County failed to adequately fulfill its local regulatory responsibilities regarding work safety; it did not carry out the efforts to “crack down on illegal activities and rectify violations” in a thorough or effective manner, nor did it properly supervise and guide relevant local departments in fulfilling their safety regulatory duties. (II) Basic Information 1. Information on the units involved in the accident: Guangrao Runheng Chemical Co., Ltd. (hereinafter referred to as “Runheng Company”) is a private joint-stock enterprise with a registered capital of 10 million yuan, fixed assets worth approximately 25 million yuan, and over 40 employees. Its predecessor was Guangrao Runheng Industry and Trade Co., Ltd., established in July 2005. In August 2008, the name of Guangrao County Runheng Industry and Trade Co., Ltd. was changed to Guangrao County Runheng Chemical Co., Ltd. Its business scope was altered from the purchasing, processing, and sales of agricultural and sideline products to the processing and sales of chemical products (excluding highly toxic, flammable, and explosive hazardous chemicals, as well as those that are restricted or prohibited; operations that require approval according to laws and regulations must be carried out with a corresponding license). Subsequently, the company made multiple changes to its legal representative, shareholders, equity structure, registered capital, etc. In February 2013, the company’s shareholders’ meeting decided that the shareholders would be Dong, Gu, Wang, and Dongying Baihua Landscape Engineering Co., Ltd., with contribution ratios of 19%, 20%, 10%, and 51% respectively; Dong served as the legal representative and executive director. The main product of the company’s pharmaceutical intermediate project is 2-chloro-5-trifluoromethylpyridine (with a production capacity of 150 tons per year); the by-products are hydrochloric acid, hydrofluoric acid, and sodium hypochlorite. The raw materials used are 2-chloro-5-methylpyridine, liquid alkali, chlorine gas, and hydrogen fluoride. The original equipment for this project was designed by Shandong Luxin Pharmaceutical and Chemical Engineering Design Co., Ltd., while the process technology was provided by an individual named Wang from Shenyang Fuxin Chemical Research Institute. Construction began in March 2008, and the project was completed in August 2008. After completion, due to various factors such as process adjustments, funding shortages, and internal equity changes, the project was unable to start operating normally (from August 2008 to March 2013, equipment tuning and experimental production were carried out on multiple occasions). From March to October 2013, Runheng Company upgraded some of the equipment for the project, replacing the chlorination reactor and the chlorine buffer tank; the capacity of the chlorination reactor was increased from 1 cubic meter to 2 cubic meters. The distillation and exhaust gas absorption units were expanded; the distillation unit was equipped with additional evaporation tanks and receiving tanks, while the exhaust gas absorption unit was replaced with a falling film absorber. The processing capacity increased from 45 cubic meters to 120 cubic meters. During the renovation and expansion period, Runheng Company carried out production in April, June, August, and September 2013, with each production cycle lasting between 5 and 14 days. On October 10, 2013, the equipment renovation was completed in its entirety, and production resumed on the 13th with the start of material feeding. 2. Project filing, approval, licensing, equipment registration, and administrative law enforcement: On January 8, 2008, the Development and Reform Bureau of Guangrao County approved the project for filing. In April 2008, the Guangrao County Housing and Urban-Rural Development Bureau approved the project site selection plan. In August 2008, the Dongying Environmental Protection Bureau imposed a penalty on Runheng Company for starting construction and commencing trial production of its 600 tons per year pharmaceutical intermediate production facility without obtaining the necessary approval documents for environmental impact assessment; the company was ordered to stop production and fined 50,000 yuan. On July 5, 2009, the Dongying Environmental Protection Bureau issued its approval opinion on the environmental impact assessment report submitted by Runheng Company, requiring that the necessary corrections be made within 3 months. The company was required to submit an application for the completion inspection of environmental protection measures related to the construction project, and only after passing such inspection could the project begin operations officially. To date, the project has not undergone final acceptance by the environmental protection authorities. In March 2009, the Dongying Work Safety Supervision Bureau organized an expert review meeting for the pre-evaluation report of this project, and submitted the review comments to the municipal authorities in accordance with the established procedures. However, the company failed to carry out procedures such as the design review for safety facilities, record-keeping for trial production, and completion inspection thereafter. The safety establishment procedures expired in March 2011. In March 2013, when renovation and expansion of the project facilities took place, the procedures for the “three simultaneities” regarding work safety still had not been fulfilled, and no safety permit for hazardous chemicals was obtained. On July 11, 2013, the Work Safety Supervision Bureau of Guangrao County determined that Runheng Company had commenced construction of its 600-ton/year pharmaceutical intermediates project without undergoing a safety condition review. Accordingly, it issued a “Decision on On-Site Handling Measures” and an “Order to Make Corrections,” ordering the company to halt production. The company was required to complete all necessary safety approval procedures by September 30; only after obtaining these approvals could it resume production. On May 16, 2012, the Quality and Technical Supervision Bureau of Guangrao County found that two boilers at Runheng Company had not been inspected beyond their due date, and that the chlorine buffer tank had not been registered. The company was ordered to make corrections within a specified timeframe; however, due to its failure to do so, it was fined 10,000 yuan. Runheng Company notified the county quality supervision bureau of the installation of its newly replaced chlorine buffer tank on July 25, 2013, but registration has not yet been completed. 2 fluorination reactors have never been registered. Since August 2008, relevant authorities in Chenguan Township, Guangrao County have conducted multiple inspections of this company, urging it to obtain the necessary permits and requiring it not to carry out production until such permits are in place. Runheng Company failed to go through the proper procedures for purchasing highly toxic hazardous chemicals, and illegally acquired chlorine from Deng (from Qingzhou, Shandong). The police have launched an investigation, and are currently pursuing Deng (from Qingzhou, Shandong) online as a suspect in this case. 3. Plant layout, processes, and equipment conditions ① Workshop layout and equipment conditions. The workshop is constructed of color-coated steel plates and is arranged in a north-south direction, with a length of 36 meters from north to south and a width of 12 meters from east to west. The main equipment of the production facility includes 6 chlorination reactors with a capacity of 1 cubic meter each, 2 fluorination reactors with a capacity of 1 cubic meter each, 2 hot oil distillation reactors with a capacity of 1 cubic meter each, 2 vacuum distillation reactors with a capacity of 1 cubic meter each, 2 buffer tanks with a capacity of 0.8 cubic meter each, and 1 constant temperature tank. The corresponding supporting facilities include one 2t/h steam boiler, one 1.5t/h heat transfer oil boiler, and one 200,000kcal/h refrigeration unit. ②Production process and the conditions under which the accident occurred. The company’s production process involves using the raw material 2-chloro-5-methylpyridine, and through processes such as chlorination, distillation, fluorination, and rectification, high-purity product 2-chloro-5-trifluoromethylpyridine is obtained. The fluorination process is the step in which the accident occurred. The reaction equation is C6H3Cl4N + 3HF = C6H3ClF3N + 3HCl↑. In this process, the purified intermediate product, 2-chloro-5-trimethylpyridine, is placed in a fluorination reactor; hydrogen fluoride is introduced, and the temperature is raised to carry out a substitution reaction, resulting in the formation of the product 2-chloro-5-trifluoromethylpyridine. The excess hydrogen fluoride and the hydrogen chloride produced are sprayed into a falling film absorber; after dissolving in water, they form a mixture of hydrofluoric acid and hydrochloric acid, which is stored in a hydrofluoric acid tank. ③Fluorination process, equipment parameters, and the structure of the connected pressure valves and deflectors. 1) Fluorination process parameters: reaction temperature of 185–190 degrees Celsius (for 8 hours), operating pressure of 0–1.5 MPa, volume of 1 cubic meter; heat exchange is achieved through a heat transfer oil jacket. At the time of the accident, the reaction of the materials had been completed; the reactor was in a state of cooling and pressure reduction, with a temperature of 150 degrees Celsius and a pressure of 0.6 MPa. 2) Main technical parameters of the fluorination reactor. Design pressure: 10 MPa for the reactor vessel, 0.6 MPa for the jacket. Design temperature: 200 degrees Celsius for the reactor vessel, 200 degrees Celsius for the jacket. Working medium: Methanol in the reactor vessel, anhydrous hydrogen fluoride (gas) ； Jacket heat transfer oil. Maximum operating pressure: 7 MPa for the reactor vessel, 0.4 MPa for the jacket. 3) Pressure feeding valve and guide tube structure connected to the fluorination reactor. There are two series-connected valves for the material discharge valve connected to the fluorination reactor: a globe valve and a ball valve. Both serve as control valves for discharging materials after the fluorination reaction. The stop valve is directly bolted to the flange of the fluorination reactor body, and it is the location where the accident occurred. The two valves are bolted together. The duct leading out from the ball valve is connected to an open, stratified tank. Figure 1: Floor plan of Runheng Chemical Co., Ltd. in Guangrao County. (III) Timeline of the accident: Date, time, and description – October 13: After completing the renovation of the process equipment, the company began feeding materials into the system to carry out chlorination and distillation processes, in order to prepare the materials needed for the subsequent fluorine chemical reactions. From October 15 to October 17, the first fluorine chemical production process was carried out. Material feeding began at 9:45 on October 17 to start the second fluorine chemical production process. At 4:22 on October 18, Yu Jinqing, the operator in the chlorination section, noticed an abnormality in the shut-off valve connected to Reactor #1 for fluorination; there was a slight leakage. He notified Zhang, the operator in the fluorination section, to go to the site to check and confirm the situation. At 4:25 on October 18, Zhang took repair tools to fix the stop valve, while Yu watched from beside the chlorination tank. Zhang secured the tool in place, grabbed the pipe above the fluorination reactor with both hands, stepped on the tool with his foot, and stood on it to apply force. At 4:26 on October 18, Zhang used pipe wrenches to clamp the hexagon of the stop valve cover in order to tighten it. At that moment, the plug of the stop valve suddenly separated from the valve body and was ejected under pressure; material inside the fluorination tank burst out in large quantities from the connection point between the valve body and the valve cover bolts. Wu, who had just arrived on the second-floor platform to take a look (right in front of the stop valve stem), was thrown to the floor of the workshop through the gap in the protective railing on the second floor. Meanwhile, the material from the fluorination tank spread rapidly over a large area throughout the workshop. (IV) Accident losses: The accident resulted in 3 deaths and direct economic losses of approximately 2.706 million yuan. Figure 2: Accident site. Figure 3: Accident valve. http://www.chemicalsafety.org.cn/uploads/allimg/161226/7-16122620162DS.jpg Figure 4: The detached valve core. (V) Analysis of the accident causes: 1. Analysis of the direct cause: Zhang, the operator at the fluorination station, violated operating procedures by failing to wear the necessary personal protective equipment. While the fluorination reactor was under pressure, he used pipe wrenches to tighten the valve cover of a shut-off valve that was already closed, resulting in excessive stress on the valve’s threaded connections and causing structural instability (thread stripping). This led to the release of toxic materials containing hydrogen fluoride. 2. Analysis of indirect causes ① Runheng Company 1) Illegal production. Failure to comply with legal procedures for obtaining permits related to work safety, environmental protection, and fire safety; illegal production of hazardous chemicals; illegal purchase of the highly toxic hazardous chemical chlorine; illegal use of unregistered pressure vessels ； Refused to comply with the production halt orders issued by relevant authorities and resumed production without permission. 2) Lack of safety production management systems. The work safety responsibility system and safety management rules and regulations do not align with the company’s actual circumstances, nor have they been officially promulgated; furthermore, the safety operating procedures are incomplete. 3) Lacks basic safety production conditions. Safety training and education are inadequate; the safety competence of employees is poor, and their safety awareness is weak. Key responsible persons as well as those engaged in special types of work are working without the necessary certifications ； Inadequate equipment management and untimely maintenance ； The workshop is not equipped with toxic gas detection and alarm devices, nor are there any safety warning signs for hazardous chemicals; the conditions for safe production do not meet the standards. ②Regulatory authorities: 1) The Chenguan Township Party Committee has failed to carry out its duties related to cracking down on illegal activities and rectifying violations effectively; safety supervision is inadequate, and hazard inspections are not thorough enough. Failing to carry out earnestly the tasks related to cracking down on illegal activities and addressing safety hazards in accordance with the requirements set out in the \"Notice from the People’s Government Office of Guangrao County on Issuing the Implementation Plan for Special Actions to Address Illegal Activities in the Hazardous Chemicals Sector\" (Guangzhengban Zi [2013] No. 37); there was inadequate supervision over the enterprises’ long-standing illegal production and operation activities, and these enterprises were not shut down in accordance with the law. Guidance, supervision, and inspection of enterprises were not carried out in strict accordance with the requirements of territorial management and shared responsibilities among Party and government agencies; insufficient guidance, supervision, and oversight were provided regarding Runheng Company’s work in ensuring safe production. Since 2008, various relevant agencies in Chenguan Township have conducted multiple inspections at Runheng Chemical Company, failing to ensure that the company obtained the necessary safety production permits and that environmental impact assessments were properly carried out. 2) The Work Safety Supervision Bureau of Guangrao County, as the agency responsible for comprehensive supervision of work safety in the county as well as oversight of the hazardous chemicals industry, failed to guide, coordinate, and urge relevant functional departments to fulfill their responsibilities in work safety management. It also failed to organize effectively the special campaigns aimed at cracking down on illegal activities and ensuring work safety in the county, and took no further action regarding companies that refused to comply with orders to suspend production. Inspections of enterprises were carried out carelessly and perfunctorily; the renovation and expansion projects undertaken by enterprises this year were not detected in a timely manner. There was insufficient enforcement and inappropriate measures taken regarding enterprises that operated without a safety production license for hazardous chemicals and engaged in illegal production activities; follow-up supervision and rectification efforts were also inadequate. 3) The Guangrao County Quality and Technical Supervision Bureau, as the department responsible for overseeing the safety of special equipment in its jurisdiction, failed to fulfill its duties related to the supervision of such equipment in accordance with relevant laws and regulations. It also failed to carry out thorough inspections and rectifications of potential hazards as required by the overall plan for combating illegal activities and violations throughout the county. During the inspection, it was found that no pressure vessels directly connected to the valve involved in the accident were unregistered, and such pressure vessels were not subject to supervision. Regarding Runheng Company, there were unlicensed personnel operating special equipment, and the safety operating procedures for special equipment were inadequate; efforts to urge corrective actions were ineffective. 4) The Chenguan Police Station of Guangrao County Public Security Bureau failed to conduct adequate inspections for potential hazards related to highly toxic hazardous chemicals in its jurisdiction, and failed to detect or address illegal activities such as Runheng Company’s unlawful procurement, use, and storage of such hazardous chemicals. 5) The people’s government of Guangrao County failed to adequately fulfill its local regulatory responsibilities regarding work safety; it did not carry out the efforts to “crack down on illegal activities and rectify violations” in a thorough or effective manner, nor did it properly supervise and guide relevant local departments in fulfilling their safety regulatory duties. II. Emergency rescue in case of accidents: After the accident occurred, the workers on duty at that time, including Li and others, immediately rescued Wu, who was lying near the south entrance of the main door in the workshop. Yu and Zhang were then evacuated from the workshop via the diagonal ladder on the south side of the workshop to the outside. Li and others carried the three people to the water pipe and flushed them. Li immediately called the 120 emergency number. At around 5 o’clock, hospital emergency responders arrived at the scene and transported the victim to Guangrao County People’s Hospital, where first aid was provided both in the vehicle and at the hospital. The three individuals died despite attempts to save them; they were diagnosed by Guangrao County People’s Hospital as having suffered from hydrogen fluoride poisoning, which led to their death. Workshop director Zhang arrived at the scene at 5:20, where he directed workers to drain the contents from other reactors and systems. He also implemented emergency shutdown measures, including shutting down the furnace, power supply, and water supply. The situation was brought under control around 6:30. The accident did not have a significant impact on the surrounding environment. At present, the follow-up work has been completed. III. Reflections and Recommendations
(1) Draw profound lessons from the incident and continue to vigorously carry out efforts to “crack down on illegal activities and rectify violations”. All levels of ** and relevant functional departments must earnestly draw lessons from the serious consequences of the \"10.18\" accident, fully recognize the extreme importance of ensuring safe production as well as the severe current situation in this regard. They should take more resolute, effective measures to prevent any production or business operations from starting up in an unsafe condition, thereby improving the safety supervision capabilities and standards of ** and related departments ； \"Cracking down on illegal and irregular activities\" should be regarded as an important aspect of work related to safe production, and made systematic and routine. All forms of illegal and unlawful production, operation, and construction activities must be severely punished. The requirements of the \"four musts\" must be strictly implemented to genuinely improve the quality of such crackdowns, ensuring thorough and effective investigations as well as real and substantive improvements ； It is necessary to establish a regular coordination mechanism for cracking down on illegal activities and addressing violations, to effectively implement the responsibilities associated with local management. Special agencies should be set up with dedicated staff, and joint meetings should be held regularly to enhance coordination and information sharing, ensuring that the responsibilities of various departments and units are properly fulfilled and preventing such efforts from becoming superficial or merely formalities. It is necessary to effectively implement the responsibilities at the county and township levels; those who fail to carry out work properly in combating illegal activities must be held accountable in strict accordance with relevant regulations. (II) Effectively implement the primary responsibility of enterprises for work safety and strengthen internal safety management within enterprises. At all levels, it is necessary to strengthen leadership over work safety effectively, increase investment in the development of the workforce and equipment for local work safety supervision agencies. By employing methods such as unannounced inspections, surprise checks, and joint inspections, the relevance and effectiveness of daily law enforcement and supervision can be improved. At the same time, administrative penalties should be intensified to ensure that production and business units comply with relevant laws, regulations, and policies regarding work safety. Production and business entities must implement the principle of “safety first, prevention foremost, and comprehensive management” to effectively carry out work related to work safety. It is necessary to strictly enforce laws and regulations regarding work safety, environmental protection, and special equipment. Without obtaining the relevant permits, approvals, and registrations, no production or business activities shall be carried out under any circumstances ； Establish and improve various rules, regulations, and safe operating procedures, and enforce them strictly ； Improve the work safety responsibility system, clarify the work safety duties for each position, and strictly enforce the performance evaluation and accountability mechanisms for work safety ； Strengthen education and training to improve the safety awareness and operational skills of practitioners ； Strictly manage special operation personnel to prevent work without proper certification ； Conduct a thorough investigation and address all safety hazards ； Strengthening emergency management requires focusing on the development of emergency plans and conducting emergency drills, in order to improve the ability to respond to accidents and disasters. (III) Further strengthen source management and effectively implement the safety supervision responsibilities of ** and relevant departments. All levels of ** and relevant functional departments must properly carry out tasks such as the review of safety conditions for hazardous chemical construction projects, the inspection of facility design, the registration for trial production, and the completion acceptance. For the safety facilities of new, renovated, or expanded projects, it is necessary to adhere to the \"three simultaneities\" principle, which requires that these facilities be designed, constructed, and put into operation at the same time as the main project itself ； It is necessary to continue to carry out thorough inspections of construction projects, strictly investigate and deal with cases of hazardous chemical projects that were built without approval, prevent new instances of illegal construction, and stop projects with poor safety conditions and outdated technology from proceeding – ensuring strict control over project approvals ； It is necessary to strictly implement the system of accountability for work safety on the part of administrative leaders, as well as the principle of \"dual responsibilities for each position.\" The responsibilities of industry authorities for direct supervision, safety regulatory agencies for comprehensive supervision, and local authorities for oversight within their respective jurisdictions must be fulfilled, so as to create a situation characterized by full commitment to duties, shared responsibilities between the Party and government, dual responsibilities for each position, and coordinated efforts from all parties involved.