Use of thermal oil

Accidents such as thermal oil should be rare in the industry.

At 18:18 on December 8, 2008, a thermal oil buffer tank explosion occurred at Anhui Chaoqiang Chemical Co., Ltd. in Huainan City, resulting in 3 deaths and 2 minor injuries. See documents from Anhui Provincial Work Safety Supervision and Administration Bureau http://www.anhuisafety.gov.cn/ma ... nfo.do?infoId=11693 Thermal oil accident in a bleaching and dyeing factory in Sichuan http://www.scaqw.com/articles/?contentid=12067 This post was last edited by lbyz on 2009-3-2 23:23 ]

The heat transfer oil used by our company has leakage. According to the training of the equipment staff, fire accidents will occur, especially if oil stains appear on the insulation material. However, micro-leakage often occurs at the flange due to the gasket. To solve the problem, the insulation material must be replaced. I don’t know what material of gasket is more suitable, so I have to recommend that the company replace the material at the penetration area frequently.； The leader was very unhappy.

To solve the problem, the insulation material must be replaced. I don’t know what gasket material is more suitable, so I have to recommend that the company replace the material in the penetration area frequently.； The leader was very unhappy.

The gaskets used for thermal oil are generally made of metal. Usually it is running at low pressure. The most terrible thing is that the boiler leaks and causes a fire.

The information content comes from the Internet, and the author is unknown. Precautions for using thermal oil: 1. Select thermal oil that complies with SH/T 0677-1999 thermal oil standards and is formulated with high-quality high-temperature antioxidant and anti-scaling composite additives, and select the appropriate brand based on the actual operating temperature. 2. In actual use, the average temperature of the main fluid measured at the outlet of the heating furnace should be at least 20°C lower than its maximum operating temperature. L-QB300 thermal oil and L-QC320 thermal oil are suitable for use in heating systems with maximum operating temperatures of 280°C and 300°C respectively. It is strictly prohibited to use thermal oil at overtemperature during operation to ensure its normal service life. 3. The temperature of the thermal oil in the expansion tank of the heating system should generally be lower than 70°C. 4. In order to extend the service life of the thermal oil, the expansion tank should be sealed with nitrogen. 5. The remaining moisture and grease in the system should be thoroughly removed before filling with thermal oil. 6. Careful inspections should be made during use to prevent water, acid, alkali and low-boiling substances from leaking into the use system, and a filter device should be installed to prevent mechanical debris from entering and ensure the purity of the heat transfer oil. 7. When replacing the old heat transfer system with new heat transfer oil, debris on the inner wall of the system must be removed to avoid affecting the heat transfer efficiency and service life of the heat transfer oil. 8. The heat transfer oil used should undergo oil analysis once a year. Its replacement index is: Carbon residue is not more than 1.5% ； The acid value is not greater than 0.5mgKOH/g ； Flash point change rate is not greater than 20% ； The viscosity change rate is no more than 15%. If two of them are unqualified, you should consider adding some new oil or changing all the oil. 9. Thermal oil furnaces and heating equipment that comply with HG 27004-1993 "Safety Technical Regulations for Organic Heat Carrier Heating Furnaces" should be used and their regulations should be followed. The following issues should be paid attention to when using thermal oil: ① The thermal oil must be kept indoors to prevent water, acid and alkali from being mixed in ； ②Thermal transfer oils of different brands and varieties from different manufacturers cannot be mixed. ； If it is really necessary to mix them, they must be sent to the relevant unit for testing. ； ③The newly activated heating device must remove impurities, welding slag, etc. that entered the heating device during the installation process, and flush it with thermal oil or special cleaning agent. ； It is also necessary to remove sediments when changing oil or overhauling ； ④When using a heating device with pump circulation, start the circulation pump first, then ignite it after normal operation, open the exhaust valve to dehydrate and remove light components, and close the valve when there is no smoke. ； During use, do not heat up too quickly within 100°C, and do not exceed 20°C per hour. When stopping use, you need to wait until the heat transfer oil drops to 100°C before stopping the pump. ； ⑤Thermal oil quality should be checked regularly (preferably twice a year), oil samples should be extracted, tested, and various indicators should be comprehensively analyzed to determine whether to change the oil and refuel. There are also related discussions in our forum http://bbs.hcbbs.com/viewthread.php?tid=260799

Thermal oil is used in areas containing flammable materials. If it leaks into the insulation layer, it is very dangerous and may spontaneously ignite. There have been similar cases in the past.

Recently, we experienced a situation where thermal oil solidified in the pipeline due to the low temperature after it was added to the pipeline, which caused some inconvenience. I hope you will pay attention to it.

Generally speaking, there are still many accidents related to thermal oil. Due to the high working temperature, a fire accident may occur if it leaks, which is quite dangerous.

You can use a metal wrapping pad, which should work better.

Generally speaking, there are relatively few accidents caused by thermal oil in chemical plants. Leakage often occurs when starting, stopping and filling new oil, which mainly has a great impact on environmental protection and water quality. Purge is also very important during start-up and shutdown, otherwise the moisture retained in the pipes will cause a significant increase in the temperature of the oven curve. * * This post was last edited by woonty on 2009-3-5 08:10 ]

Our company uses heat transfer oil. During the use of heat transfer oil, especially when it is close to its service life, frequent composition analysis is required to avoid simply heating the furnace temperature when the oil quality does not meet the requirements, causing the oil to vaporize and then cause a burst accident.

Thermal oil and fuel oil have strong permeability and fluidity. If there are problems such as welding quality defects, missing safety accessories, operating errors, etc., overpressure, pipe bursts, leaks, fires, explosions and other accidents may occur during the production process. Thermal oil is transported through pipelines in the production plant. Temperature changes may occur during the production of the pipelines. Thermal stress may cause pipeline damage and cause leaks, fires, and explosions. Deterioration and carbonization of the heat transfer oil during use may lead to coking of the pipeline, and local overheating may occur, causing the pipe to burst. During the startup process, as the organic heat carrier is heated, other gases or moisture dissolved in it gradually separate, which may cause overpressure and bumping accidents. Thermal oil expands and contracts due to temperature changes, which may cause local gas phase or oil spill, overpressure and other accidents in the equipment.

What is the function of the thermal oil buffer tank?

At the request of cyfmaill, a notice on the "12.8" thermal oil buffer tank explosion accident of Huainan Anhui Chaoqiang Chemical Co., Ltd. was posted to the Municipal Work Safety Supervision and Administration Bureau.: At 18:18 on December 8, 2008, a thermal oil buffer tank explosion occurred at Anhui Chaoqiang Chemical Co., Ltd. in Huainan City, resulting in 3 deaths and 2 minor injuries. After the accident, the province * * The leading comrades attached great importance to it and immediately issued important instructions, requiring all-out treatment of the injured, proper handling of the aftermath of the accident, rapid identification of the cause of the accident, accountability for safety accidents, investigation of surface safety production, and resolute prevention of similar accidents. That night, the Provincial Safety Supervision Bureau immediately assigned the person in charge of the Hazardous Chemicals Department and experts to rush to the scene overnight to assist and guide the accident investigation and handling. local * * Attaching great importance to it, the main responsible comrades rushed to the scene in time to guide the rescue. At the same time, an accident investigation team was established to investigate the cause and responsibility of the accident. According to preliminary analysis, the main cause of the accident was that the thermal oil leaked when maintenance personnel were inspecting the flange between the circulating thermal oil buffer tank and the outlet oil pump. The leaked thermal oil was affected by the heat source of the reactor and ignited. The fire source caused the oil in the thermal oil buffer tank to heat, vaporize, and explode. The accident fully exposed the chemical enterprise's failure to implement the safety production responsibility system, and the serious "three violations" such as illegal command, illegal operation, and violation of labor discipline. ； The intrinsic safety level is low, and the construction project has not passed the "Three Simultaneities"” ； The enterprise's on-site safety management is not strict, no safe operation plan is formulated during special operations such as inspection and maintenance, and operations are carried out without taking protective measures ； The safety education and training of enterprise employees is not in place, and employees have poor safety awareness, poor operating skills, poor emergency response capabilities, and inadequate hidden danger investigation and rectification work. In order to implement the provincial * * In the spirit of the important instructions of the main leaders, we must conscientiously learn the lessons from this accident, further improve chemical production safety during the "New Year's Day" and "Spring Festival", eliminate illegal production, and prevent the recurrence of similar accidents. The following requirements are hereby put forward: 1. Further improve the safety production of chemical enterprises this winter and next spring. At present, our province has entered winter. The safety supervision bureaus at all levels must combine the characteristics of winter production safety, focusing on preventing freezing, anti-condensation, anti-static, anti-dust explosion, and preventing the rush for progress and production at the end of the year, and urge chemical companies to regularly check the integrity of chemical production equipment and safety facilities. Conduct systematic inspections of the conditions, strengthen daily maintenance of equipment, do regular inspections and inspections of safety facilities, take effective safety measures, and implement protective measures such as anti-freeze, anti-slip, anti-leakage, and anti-poisoning measures for winter production equipment and facilities and pipelines. Enterprises that use production shutdowns for inspection and maintenance must ensure that there are no residual materials in equipment and pipelines ； Enterprises that produce synthetic ammonia, liquid chlorine, benzene and methanol must strictly implement patrol inspection systems and strengthen monitoring of flammable and explosive chemical tank areas and highly toxic chemical storage areas to prevent production safety accidents and ensure that chemical enterprises can survive the winter safely. 2. Implement the main responsibilities of chemical enterprises and effectively carry out anti-"three violations" activities. Safety supervision bureaus at all levels must urge chemical companies to formulate strict safety operating procedures. During inspection and maintenance operations such as fire work, earth work, entry into restricted spaces, high-altitude operations, and temporary use of electricity, dangerous operation approval procedures must be strictly carried out as required. Operating equipment that affects each other must be effectively isolated, and effective monitoring measures must be taken to prevent accidents caused by risky operations when hazard factors are unknown or protective measures are unreliable. Safety supervision departments at all levels must promptly stop the "three violations" discovered and deal with them in accordance with the law, and will never tolerate or tolerate them. 3. Effectively strengthen safety supervision of chemical construction projects. Safety supervision bureaus at all levels must strictly manage the "three simultaneous" management of chemical construction projects, and effectively do a good job in safety licensing of new, renovated and expanded chemical construction projects. In accordance with the provisions and requirements of relevant laws and documents, all chemical enterprises should implement the "three simultaneousnesses" of safety facilities and main projects in new construction, reconstruction, and expansion projects. Safety assessments must be conducted and designs must be carried out by qualified design units to ensure that projects put into operation meet safe production conditions. For chemical enterprises that have not implemented the "Three Simultaneities" for safety facilities or have put into production without safety facility acceptance, they should complete the procedures within a time limit. If they still do not complete the procedures, construction or production will be stopped. 4. Further strengthen safety education and skills training for employees. Safety supervision bureaus at all levels should urge chemical companies to continue to strengthen the education and training of employees, especially those working in new equipment and migrant workers, so that they have corresponding operating skills and emergency response capabilities. After passing the training and assessment, they can start working with certificates. It is necessary to continuously strengthen the training of operators' operational skills and emergency response capabilities, and strengthen drills on the basis of continuously improving various emergency plans to improve the company's emergency command and emergency response capabilities in accidents. 5. Seriously carry out the "look back" work on safety production inspections of chemical enterprises. Safety supervision bureaus at all levels must learn lessons from this "12.8" accident, draw inferences from one example, and follow the requirements of the State Council Safety Commission's inspection of chemical enterprise safety production by all enterprises and localities * * The coverage of organizational self-inspection must reach 100%, and forces must be quickly organized to carry out "look-back" inspections on small chemical industries below the scale, chemical companies with incomplete front-end hidden dangers, chemical companies that have experienced fatal accidents this year, and chemical projects that are about to complete trial production, and any hidden dangers discovered must be rectified immediately. Supervise and guide chemical enterprises to establish and improve the continuous hidden danger investigation and management system, and establish a long-term mechanism for enterprise safety production. All municipal safety supervision bureaus are requested to forward this notice to relevant departments and chemical companies within their jurisdiction as soon as possible. Anhui Provincial Work Safety Supervision and Administration Bureau December 11, 2008

During initial start-up, it is important to dehydrate the heat transfer oil, otherwise it is easy to cause oily water to emerge from the top of the high-level expansion tank when it is vented.； A pipeline filter should be installed at the pump inlet because after the thermal oil system is constructed, it is generally not cleaned with water. Welding slag is easily collected during system installation. Installing a pump inlet filter can avoid damage to the pump impeller. ； It is recommended to use graphite winding pads for the heat sheets of pipe flanges, because the permeability of heat transfer oil is strong, and ordinary rubber asbestos sheets cannot prevent the leakage of heat transfer oil.