Questions about “one tank, one dike”
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The plant has recently installed a new unit, which includes a horizontal storage tank for storing toluene; the dimensions of this tank are φ1200X4000. The design institute did not construct fire protection dikes or barriers in accordance with GB50160. In addition, in accordance with the requirements set out in the Notice of the State Administration of Work Safety on Further Strengthening the Safety Management of Chemical Storage Areas, Document No. An Jian Zong Guan San [2014] 68, the principle of \"one dike per tank\" should be applied. When reviewing the safety aspects of this project, we encountered a difficult question: for such storage tanks, is it indeed necessary to design a fire dike, and should there be one dike per tank? At present, the piping and other basic designs for this unit have been completed. If the design institute is required to follow the instructions and adopt a \"single tank, single dike\" design, then the civil work, water supply and drainage systems, piping, and other aspects related to this unit will all change. We’re not sure either whether the design institute will make any changes; has anyone encountered such a problem?
All projects after 2014 have this requirement. But there can be dike between the tanks; it’s not necessary for them to all be filled with fire dikes.
This horizontal storage tank is used to store toluene. Although its dimensions of φ1200X4000 are not large, since it is a Class A storage tank, I believe that appropriate fire protection measures should still be implemented in accordance with GB50160 or GB50016 whenever it is installed outdoors. If it is to be buried, a tank pit must be constructed; it cannot be buried directly. The diesel tank in the boiler room has a capacity of only one cubic meter, and the regulations also require the installation of devices to prevent the liquid from spreading.
That’s why I noticed this issue while reviewing the safety section of this project. It seems that the preliminary design for this project is already ready; if we raise requests now, the design institute will get annoyed with us again.
The special safety review has indicated that the design institute must make modifications; otherwise, it will not pass the completion inspection.
This problem arises mainly because some designers, including certain experts, believe that only the mandatory provisions in the standards need to be followed, while other provisions can be ignored. Another point is that they believe it is not necessary to install a fire dike around the intermediate storage tank in the facility, but the regulations explicitly state that such a fire dike must still be in place for the intermediate storage tank. In fact, each regulation is the result of summarizing various lessons learned; compliance is the foundation of safety, while non-compliance is a source of risk.
In accordance with the requirements of 4.2.4 in GB50016, a fire dike must be installed. Although this is not mandatory, given that it is a new project and considering the current emphasis on tank safety in regulatory oversight, a fire dike must be provided for the toluene tanks.
I have presented all my suggestions in full, as you know. For some large state-owned enterprises, many projects are launched following the principle of \"getting on board first and buying the ticket later\"; the design institutes are part of the same system. Once these suggestions are put forward, various aspects of the initial design, such as the overall layout, equipment, and processes, will need to be modified. I’m worried that certain leaders might ignore these suggestions and treat them as nothing more than mere suggestions. The biggest fear is the \"experts\" from the safety supervision agency, who failed to spot the issues with the safety design. By doing this, it creates significant risks for future production.
It was completely a decision made arbitrarily by the safety supervision agency; in practice, it’s very difficult to implement, as many places do not require this. **Standard specifications are indeed the result of discussions and evaluations by many experts from related industries. But I wonder whether the Safety Supervision Bureau sought public or expert opinions before issuing this document; moreover, the document is not thorough – how can tanks with a capacity of 10,000 cubic meters be treated in the same way as those with a capacity of 50 cubic meters? Is it necessary to add another partition between the 2 tanks of 50 cubic meters each?