A few days ago, State Administration of Science, Technology and Industry for National Defence, PRC sent us a letter of thanks, speaking highly of the significant contributions that Beijing Institute of Technology played in the “Aug 12th” accident investigation of the great fire explosion of dangerous cargo warehouse of Ruihai Company at Tianjin Port, and expressing sincere thanks.
Based on the political consciousness and overall consciousness, Beijing Institute of Technology fully took special advantages of military industry, actively organizing forces to participate in the accident investigation. State Key Laboratory of Explosion Science and Technology and other units, Qian Xinming, Wang Cheng and other teachers kept their mission in mind, having the courage to play, not thinking of gains and losses, overcoming difficulties, deepening into the front line, continuing their jobs, played an important role to find out direct reasons for the accident through high level and professional scientific analysis, which was highly recognized by accident investigation team of State Council and State Administration of Science, Technology and Industry for National Defence, PRC.
The picture is a photo of the site of “Aug 12th”accident at Tianjin Port
On Aug 12th,2015, a fire explosion accident happened at the dangerous cargo warehouse Tianjin Ruihai International Logistics Co; Ltd at Tianjin Port of Tianjin City, causing 165 deaths, 8 missing and 798 injured, it was a particularly serious production safety accident, arousing high attention both domestic and overseas. After the accident, the Party Central Committee and the State Council paid high attention, according the spirit of important instructions of central leaders and related laws and regulations, approved by the State Council and led by Ministry of Public Security, the accident investigation team of fire explosion accident happened at the dangerous cargo warehouse Tianjin Ruihai International Logistics Co; Ltd at Tianjin Port was founded to carry out a deep survey into the accident.
“450 tons of TNT equivalent”, Beijing Institute of Technology being entrusted with a mission at a critical and difficult moment.
Beijing Institute of Technology (BIT) not only has the only state key laboratory in the field of explosion in the nation, but also its research on explosives and powders is advanced in the world. Having engaged into the accident investigation in domestic major and extraordinarily serious explosion accidents, faced with this extremely major fire and explosion accident, call of the nation is the mission and responsibility, BIT was entrusted with a mission at a critical and difficult moment!
After the explosion accident, BIT carried out the organization and coordination work immediately according to demands of the superior. Professor Qian Xinming of State Key Laboratory of Explosion Science and Technology was asked to enter the “Aug 12th” accident investigation team of the State Council. After receiving instructions of the superior, Professor Qian Xinming suspended all his arrangement of the holidays immediately, devoting into the work on Aug 18th to go to the accident site.
The left is Professor Qian Xinming, the right is Professor Wang Cheng
There are wide ramifications and extremely destruction of explosion in this fire and explosion accident, moreover dangerous chemicals were of diversified kinds and types, and there was serious pollution on the site, the accident investigation had great technical difficulty, there was high attention both domestic and overseas. And due to the disordered management of the accident unit- Ruihai Company, all information and data were ruined, starting from zero, all these had brought unprecedented challenges to the accident investigation team.
Faced with such a difficult and complicated situation, in conformity with seeking truth from facts, objectivity & fairness as well as science rigorousness, Professor Qian Xinming and Wang Cheng and other members of the investigation team carried out investigation of the accident through day and night breaking the routine solidly and strongly. Professor Qian Xinming was primarily responsible for the mechanism of exploding and burning in the accident, analysis of the explosion process and analog computation of the TNT equivalent, Professor Wang Cheng made analogue simulation for the explosion process by means of the independently researched and developed high-precision and large scale simulation software ExVisual for the explosion, energy of the first explosion was computed as 15 tons of TNT equivalent, and energy of the second explosion was computed as 430 tons of TNT equivalent. Considering there were many explosions of small scale, finally the total energy of this explosion accident was determined to be about 450 tons of TNT equivalent. Core technical work in the accident that experts from BIT in charge made important contributions to uncover the truth of the accident.
Representing origin of the fire accident, BIT experts opened the First Door of the accident investigation
Determination of combustion source were the starting point and key in any investigation. For the “Aug 12th” fire explosion accident at Tianjin Port, due to the large explosion energy and long-time combustion, resulting in difficulties in looking for reference evidence, which brought significant challenges for the determination of fire source. So in the starting stage of the accident investigation, determination of the burning material and ignition source was the technical core of the whole accident investigation.
There were two dim fire videos left to the investigation team. The investigation team collected on-site information of hazard substances bit by bit from departments of customs, communications, safety supervision and so on, one by one comparison test was applied to understand conditions of combustion source and flame by means of field tests aiming at determining condition of the combustion source. But there were large differences between lots of testing results and accident conditions, after countless failures, Professor Qian Xinming boldly proposed the assumption that nitro-cotton was the ignition substance. Under support of State Administration of Science, Technology and Industry for National Defense, PRC, related testing programs were designed and authoritative institutions were entrusted to perform acid-containing dry nitro-cotton thermal stability tests and large scale nitro-cotton ignition tests. Through scientific tests and on-site accident video comparison on flame structure and features of the combustion substance, also combing with weather condition, storage condition, job analysis of production and carry, finally nitro-cotton was determined as the fire material, opening the First Door of the accident investigation. In the demonstration of this key aspect, State Key Laboratory of Explosion Science and Technology of BIT played an important role, it was also the only technical supporting unit mentioned in the accident investigation report, BIT successfully accomplished its mission.
It is worth mentioning that Professor Qian Xinming “a word telling the truth” in the critical moment, had made important contributions to the technical investigations of many domestic especially serious explosion accidents. For example, in the “June 3rd” especially serious explosion accident in Baoyuanfeng Poultry Industry Company in Jilin province, through comparison tests and numerical simulation, he made significant contributions to tell whether the fire was caused by ammonia gas explosion or ammonia gas explosion was caused by the fire; in the “Nov 22ndd” especially serious explosion accident at Huangdao in Qingdao, through the field tests at east garden base of State Key Laboratory of Explosion Science and Technology, he perfectly represented the explosion process and made significant contributions to represent the destroyed situation of the accident and quantification of the accident. All work above was spoken highly by investigation team of the State Council.
Great effort in Chinese explosion, casting safety barrier for the nation
It was not achievement in a single day that BIT uncovered truth of the accident by means of scientific methods in such a complicated especially serious fire explosion accident. Among these are silent accumulation devoted to the military industry and focusing on scientific research, also there were home and country emotions of BIT people showing great effort in Chinese explosion industry and casting safety barrier for the nation.
As the only domestic highest level research platform on explosion technology, State Key Laboratory of Explosion Science and Technology of Beijing Institute of Technology had significant influence in both domestic and overseas explosion research area. Over the years, with the pulling of significant demands and development of explosion science and technical subjects of the nation’s safety, with development of ammunition and weaponry, combining with demands of explosion prevention and control in civil explosion area, with original innovation as the core, centering on development of domestic defense-related science and technology and public safety in the new era, aiming at basic theories and key technical problems, systematically and deeply carrying out basic and application foundation research, the laboratory highlights research on new theories, new technologies and new application methods in the field of explosion damage and safety. It has not only made significant contributions in talents training, scientific research and spanning development of weaponry, but also it has directly pushed the disciplinary development and technological innovation of explosion prevention and control of civil explosion area and so on.
Currently, with the support of Creative Research Group-National Natural Science Fund for of “Dynamic Mechanical Behavior of Complicated Media/Structure” and the three national level innovation teams of Explosion & Damage Technology, New Concept/ New Type Structural Function Technology, Damage & Prevention Material, the laboratory has been a training base for high level talents in explosion science and technology area in the nation.
Over the recent years in the field of civil explosion safety, the laboratory has not only established a series of high level explosion reaction models, including reaction model for dangerous chemical under coupling of thermal-force-chemical reactions, heat conduction and radiation model, thermal ignition and initiation model, detonation model, constitutive of multi kinds of materials, but also it has constructed computational format of the physical quantity in the high precision calculation of explosion, proposing high precision calculation methods under mutual reaction of complicated boundary and multi-material interface, a simulation software with high precision and large scale was researched and developed. Moreover, the gas-phase explosion, dust explosion, condensed phase explosion and multi—phase detonation simulated testing system can simulate and represent the closure condition, semi—closure condition and the evolution process of the explosion accident under open environments.
These research achievements provide important theoretical foundation and technical support for research on the cause and evolution rules of the explosion accident, playing a significant role in the analysis and investigation in many serious and major accidents including the “Aug 12th” especially serious fire explosion at dangerous cargo warehouse of Ruihai Company at Tianjin Port.
Engaged in the explosion science and technology, accompanied with risks, with heritage of Yan’an Spirit, in such a university devoted into military industry and national defense- Beijing Institute of Technology, BIT people from generation to generation always take meeting demands of the national as their own duty, through concentrating on studies and silent accumulation to serve the nation when the nation when its people are in danger and disaster and in need.
