Zhang Yan, Chairman of Pretech (China): "Small Valve" Brings "Hard Protection" to Storage Tanks

China Industry News reporter Huo Yue

"Flame arresters, breathing valves, and emergency pressure relief valves for liquid hydrocarbon storage tanks in the petrochemical industry were previously collectively referred to as safety accessories, and people didn't pay that much attention to them." As a technical expert who has been deeply involved in the industry for more than 20 years, Zhang Yan, chairman of Pretech (China), said that with the country's emphasis on safety and environmental protection, as well as the transformation of concepts, the development of technology application, and the increase of environmental protection governance, flame arresters, breathing valves, and emergency pressure relief valves have received more and more attention and become important storage tank safety and environmental protection equipment.

Zhang Yan, Chairman of Pretech (China).

Domestic technology needs to keep up with the latest standards

In the petrochemical industry, the storage tank is the main link in the emission of volatile organic compounds (VOCs), and the high-efficiency and environmentally friendly fire-retardant breathing valve and emergency pressure relief valve can improve the sealing of the storage tank, play a key role in the source treatment of volatile organic compounds, and bring "hard core protection" to the storage tank. The flame retardant breathing valve can not only prevent the storage tank from being damaged due to overpressure and ultra-vacuum, but also effectively block the flash explosion or combustion of oil and gas, protect the safety of the storage tank, and at the same time enclose a large amount of oil and gas in the storage tank to reduce the emission of volatile organic compounds in the storage tank. The emergency pressure relief valve can prevent the tank from being damaged by the sharp increase in pressure in the tank in the event of an emergency.

"Although the technology of domestic flame arresters, breathing valves and emergency relief valves has been improved in recent years, there is still a big gap compared with foreign advanced technology. Most of the existing breathing valves and emergency relief valves in China lack safety and environmental protection technology and do not meet the requirements of the latest standards. For example, without 10% low overpressure valve disc technology, the valve sensitivity is poor, the pressure relief safety is not guaranteed, and the operation effect of the oil and gas recovery device is affected at the same time; The breathing valve is equipped with a deflagration flame arrester, not a flame-resistant flame arrester, which does not meet the requirements of GB/T50759-2022 "Technical Standard for Oil and Gas Recovery and Treatment Facilities"; Failure to carry out mechanical safety certification, do not meet the requirements of GB/T3836.28 and GB/T3836.29; serious leakage, not only does not meet the environmental protection requirements, but also will cause oil and gas recovery can not be recovered; the use is unsafe, encountering easy crystallization, polymerization of medium, or used in cold areas, the valve is very easy to fail. In general, the current domestic breathing valve technology cannot meet the latest national safety and environmental protection requirements. Nearly 20 years of study and work experience in Germany has allowed Zhang Yan to see Germany's advanced concepts, technical advantages and typical experience in tank farm safety and environmental protection risk control, including tank farm safety and environmental protection risk control concept, full life cycle operating cost analysis, volatile organic compounds fugitive emission control and disposal, etc., and also feel the problems and gaps in domestic traditional technology products.

In order to actively explore the green development path of hazardous chemical tank farms, learn from advanced technology and experience, and improve the safety and environmental protection level of the domestic storage tank industry, Pretiger, as a co-organizer, held a high-level forum on the integration of safety and environmental protection risk management and control of hazardous chemicals liquid hydrocarbon tank farms in China and Germany on November 4. Zhang Yan proposed at the meeting that the breathing valve and emergency pressure relief valve under the latest safety and environmental protection standards must meet six technical requirements, namely discharge safety, mechanical safety, fire retardant safety, use safety, leakage safety, and inspection safety.

Become the guardian of tank safety and environmental protection

"Flame arresters guard 'safety', breathing valves guard 'environmental protection'." Speaking of Pretek's products and technologies, Zhang Yan talked eloquently. The high-efficiency, environmentally friendly, integrated flame retardant breathing valve and emergency pressure relief valve developed by Pretech can not only provide overpressure and vacuum protection for the storage tank, effectively prevent combustion and deflagration from entering the storage tank from the breathing port, but also solve the problem of long-term continuous leakage, avoid fire and explosion, achieve intrinsic safety, and meet the requirements of the latest national and industry standards.

It is worth noting that Pretech has also developed customized products for different media and different operating conditions, providing users with a variety of solutions, such as self-powered anti-crystallization and anti-polymerization solutions for styrene, acetic acid, phenol and other easy-to-crystallize and easy-to-polymerize media, anti-solidification solutions for heavy oil, residual oil, wax oil, asphalt and other easily coagulable media, as well as anti-icing solutions for cold areas.

In 2022, the volatile organic compounds treatment project of 66 heavy oil tanks of Sinopec Qilu Petrochemical Refinery adopted the scheme of "adding 10% low overpressure and low leakage environmentally friendly anti-coagulation integrated flame retardant breathing valve", which received good results. Zhang Yan introduced that since the operation of the project, the breathing valve has worked normally, the opening and closing are sensitive, the sealing is good, and the leakage has been reduced from 1000ppm-8000ppm before the transformation to less than 100ppm.

Sinopec Cangzhou Refining & Chemical Co., Ltd. began to use Pretek's high-efficiency and environmentally friendly integrated fire arrestant breathing valve and emergency pressure relief valve in November 2018, and after three months of operation, Cangzhou Refining & Chemical Co., Ltd. investigated the nitrogen consumption of some storage tanks and found that the average monthly nitrogen consumption was reduced from 723,662 Nm³ to 681267 Nm³, the average monthly consumption was reduced by 5.86%, and the average monthly cost was saved by about 49,000 yuan, and the overall energy saving and efficiency improvement effect of the enterprise was more obvious. Through regular maintenance every year, the valve is in good condition, and so far in operation, all environmental protection indicators have met the requirements, achieving the purpose of small investment and large income.

At present, Pretek's safety and environmental protection technology has been applied in new large-scale refining and chemical integration projects in recent years, such as Sinopec Zhongke Refining & Chemical, Sinopec Gulei Petrochemical, PetroChina Guangdong Petrochemical, Zhejiang Petrochemical, Shenghong Refining & Chemical, as well as the storage tank volatile organic compounds treatment projects of many enterprises, with good results. In March 2021, the Environmental Development Center of the Ministry of Ecology and Environment conducted a technical evaluation of the technology of Pretek environmental protection breathing valve and emergency pressure relief valve, and recognized that the emission concentration of volatile organic compounds in the environmental protection breathing valve and emergency pressure relief valve of Pretek is between 1.61 and 15.2 mg/m³, which meets the requirements of GB/T37822 "Volatile Organic Compounds Fugitive Emission Standard" for a special emission limit of 20 mg/m³. "Committed to safety and environmental protection, and contribute to the strength of Preteg to win the battle for blue skies." Talking about these successful cases, Zhang Yan concluded.

Quality service is a vital factor

"We have basic technology, experimental data, core technology, and product quality, but these are not enough, and a vital link is missing, that is, service." Zhang Yan said that service is an extension of products, and Pretech is a technical service provider for tank safety and environmental protection. No matter how good the equipment is, if it cannot be used or used improperly, it will be unqualified and even lead to safety accidents. Therefore, Pretek does not wait until the customer has a request or a product problem before investing, but has a sense of service to guide customers to use and maintain the equipment correctly. "In fact, users are not only buying our products, but also enjoying our services. We help them better understand industry standards, address issues throughout the equipment lifecycle, and ensure tank tightness. ”

In addition, Pretek's on-line inspection and repair technology of breathing valves includes portable test instruments, inspection auxiliary valves, explosion-proof data acquisition systems, etc., which have the advantages of reducing safety and environmental protection risks and improving operation efficiency compared with traditional offline inspection technology, which meets the inspection requirements of national and industry standards for in-use breathing valves, avoids damage to breathing valves caused by offline inspection and hoisting handling, and saves a lot of costs for enterprises. "On January 6 this year, Sinopec Yangzi Petrochemical successfully carried out the first online inspection of the breathing valve on the top of the aviation fuel tank of the storage and transportation plant, and received good results. Sinopec News Network also made a special report on this, which fully verified the advantages of the online inspection technology of the breathing valve and the value of application and promotion. Zhang Yan introduced.

"Concept, technology, service, these three keywords will be our goal as always." Zhang Yan said that Pretech should not only provide users with high-quality products and services, but also contribute to the country's carbon peak and carbon neutrality, and all of this comes from solid technological innovation strength.

Review: Yu Zaozao

Editor-in-charge: Huo Yue

Editor: Hu Na