Niu D.,Dalian Maritime University |
Niu D.,Guangdong Dapeng LNG Co. |
Gao C.,Dalian Maritime University |
Xie X.,Dalian Maritime University |
Bao T.,Dalian Maritime University
Natural Gas Industry | Year: 2015
As the central part of ship production plan for LNG shipping, fleet deployment is a complex optimization and decision program, which is mainly used to realize rational allocation of various ships on a number of routes. Based on the characteristics of LNG shipping (high stability requirement, strong planning and liner shipping similarity), a mixed integer programming optimization model for LNG shipping was built with the operation cost minimization as the aim and cargo quantity, time, frequency and ship quantity as the constrains, by means of the modern optimization technique of large-quantity industrial material transportation and liner transportation fleet deployment. In order to further explain the practicality of this model in the fleet deployment of LNG shipping, optimization platform LINGO 14.0 was used to conduct simulation analysis on the fleet deployment of a certain LNG shipping company. Results show that transport capacity is legitimately distributed on all routes and the whole operation cost is minimized. It is concluded that the optimization model is simple and feasible, and the proposed fleet deployment program can meet the needs of LNG shipping organization, so it can provide theoretical basis for the fleet deployment of LNG shipping companies. ©, 2015, Natural Gas Industry Journal Agency. All right reserved.
Yuan X.,Industry Risk Control |
Lu Y.,Industry Risk Control |
Zheng S.,Guangdong Dapeng LNG Co.
Huagong Xuebao/CIESC Journal | Year: 2015
As the earliest in-service LNG terminal in China, GDLNG terminal had adding/ modifying some equipments and safety instrumented function (SIF) after five years' heavy duty operation. To ensure the integrity and reliability of the safety instrumented system (SIS) in terminal, and the availability under heavy duty operation, terminal had performed Hazard and operability study (HAZOP). Based on the hazardous scenarios identified in HAZOP, Safety integrity level (SIL) classification, SIL verification and SIL re-validation had been performed to LNG terminal. The SIL classification is using layer of protection analysis (LOPA) method, which is less conservative than risk graph method used in design phase. According to SIL verification result, some SIFs in the terminal can not match SIL classification requirement. Sensitivity analysis had been performed to those SIFs. Impacts of optimizing SIS system configuration (without component hardware change, i. e., proof test interval, proof test coverage etc. ) to the probability of failure on demand (PFD) had been studied. According to the sensitivity study result, SIL level can be somehow modified without component hardware change. Under certain circumstance, it can help us to a more cost-effective approach to fulfill company SIL requirement or risk acceptance criteria. Key technical points/ difficulties and its possible solutions with SIL verification study are summarized, as well as the prospective development of SIL study. © All Right Reserved.
Wang L.,Northeast Petroleum University |
Wang L.,Guangdong Dapeng LNG Co. |
Wang L.,Times Financial Center |
Liu Y.,Northeast Petroleum University |
And 3 more authors.
Natural Gas Industry | Year: 2010
The large-scale atmospheric LNG storage tank is an important facility at LNG receiving stations and it involves high investments. It requires high commissioning techniques when it comes on stream. The most crucial and dangerous step in the commissioning of LNG storage tank is cooling. A discussion on the cooling process of the common 160,000 cu m-in-capacity atmospheric LNG storage tank in China covers the preconditions and matters to which attention is paid upon the cooling of tank; and the commissioning techniques needed in the cooling process, including pressure control, cooling medium (LNG) supply, and its flow control, process monitoring and cooling rate control. The displacement of pipelines is easily to be over-large and flange leakage takes place frequently in the cooling process and it gives corresponding solutions. So it provides good references for other LNG projects.
Wu P.,Guangdong Dapeng LNG Co. |
Wei G.,Guangdong Dapeng LNG Co. |
Wang H.,Guangdong Dapeng LNG Co.
Natural Gas Industry | Year: 2013
Sea water is regularly used for the LNG gasfication in an LNG receiving terminal. However, in the actual operation, there exists a certain risk that a great number of the sea creatures are attached to the pipe lines and equipments. To mitigate such a risk, the electrolyzed seawater is generally adopted to produce the sodium hypochlorite liquor, which with a certain concentration is thus injected into the sea water system. This paper aims to obtain the optimal selection of devices' operation mode and the set value of the chlorinity in sea water, thus to guarantee the sea water lines unobstructed and the gasfication devices kept running smoothly. In a case study of the Guangdong Dapeng LNG Terminal, a number of substantial running and test data were first collected and discussed as well as the information on the internal inspection and sampling in those sea water lines. In combination with the characteristics of such involved running devices and equipment, this paper investigates how the chlorinity of sea water and the operation mode of the corresponding devices were optimized together to meet the requirement of both production and environment. The following findings were discovered. (1) In summer and autumn, the daily chlorinity should be better at 0.5-0.8 mg/L and be improved to be about 0.95 mg/L during the red tide, thus to keep a necessary level of effective chlorinity; in autumn and winter, the daily chlorinity should be at 0.45 mg/L or even lower than that. (2) The operation mode of the unit should be of a single set of equipment and switch & maintenance on a regular basis. Meanwhile, the dischargeable capacity of the dehydrogenation tank should be considered and it is suggested that the continuous chlorination should be suspended before the chlorination impact is performed, thus to guarantee the dehydrogenation time needed.
Xu X.,Petrochina |
Xu X.,Guangdong Dapeng LNG Co. |
Huang W.,Petrochina |
Huang W.,Guangdong Dapeng LNG Co. |
And 2 more authors.
Natural Gas Industry | Year: 2010
The Tanglang section of Guangdong LNG pipelines needs to be relocated because of the plan for Shenzhen's subway line 5. For the reason of terrain restriction, tapping operation under pressure and plugging should be performed on the pipeline with an inclination angle of 20°. The welding test, tapping and plugging simulation test were performed in the form of simulation testing. A number of test parameters was acquired and the technical difficulties were resolved. Pipeline plugging without shutdown was realized.