SIAD Macchine Impianti (SIAD MI), the SIAD Group's engineering company, has installed and started up a re-liquefaction plant at the Port of Ravenna, Italy, for the evaporated natural gas (boil-off gas - BOG) at the service of the small scale LNG and four cryogenic compression packages (BOG compressors) for the recovery and re-liquefaction of evaporated natural gas.
The installation is located in an LNG storage facility owned by Depositi Italiani GNL (DIG), a company jointly owned by the PIR group (Petrolifera Italo Rumena), Edison, the latter in charge of the engineering implementation of the project, and Enagás (through its subsidiary, Scale Gas).
The storage facility consists of two atmospheric storage tanks for LNG. The LNG is transported by Edison to Ravenna by means of LNG carriers, transferred and stored in the tanks at the depot and made available for bunkering or to be loaded by tankers and distributed on the mainland at the filling stations.
The storage facility has a capacity of 20 000 m3. Having a potential annual handling of more than 1 million m3 of LNG, it will be able to refuel up to 12 000 trucks and up to 48 ferries per year, and will therefore be a strategic point for LNG refuelling throughout the northern Adriatic for maritime transport and for the central-north for land transport. This is a fundamental investment to make the transport sector more sustainable. By using methane as a fuel, emissions of sulfur oxides and particulate matter can be reduced to zero, with a 20% reduction in CO2 emissions compared to traditional fuels.
In this context, SIAD MI has been involved in the compression and reliquefaction of the BOG. During the various transfer operations (from the LNG tanker and during distribution), liquid methane partly vaporises and passes from the liquid state to the gaseous state, namely the BOG, which is first compressed and then reliquefied in order to be reintroduced into the storage tanks.
The reliquefaction plant developed by SIAD MI will enable it to treat 1100 kg/hr of methane, for a total of approximately 26 tpd of recondensed gas, thus making it possible to exploit LNG supplies with considerable savings in the long term. Additionally, the green footprint that characterises the plant is particularly significant: as a result of the use of methane, it is estimated that there will be an overall saving of 6 million t of CO2 during the lifecycle of the plant, compared to the use of other fuels.
The company also designed and supplied four BOG compressors, which are oil-free and with ATEX certification for installation in potentially explosive atmospheres. Of these four compressors, two will work at the service of the plant for the reliquefaction of the evaporated gas and the other two will be involved in managing the gas boil-off during LNG transfer operations from the LNG carrier to the storage facility.
In order to achieve the ambitious objectives of this plan, DIG has chosen the SIAD Group as a reliable partner for a ‘100% Made in Italy’ project, starting with the parent company SIAD, with its national distinction in the field of technology and gas management, which supplies the nitrogen. SIAD MI's reputation for the creation of tailor-made projects combines engineering experience with an approach based on the design of solutions specifically constructed for the requirements of its customers. This results in a plant characterised by a high modularity level. Pre-assembled and assembled on modules, it guarantees rapid installation, with a further endorsement of the company’s operational effectiveness.
The plant design and construction work by SIAD MI began in August 2019, and was completed in 11 months, perfectly in line with the design requirements, which were met and maintained, notwithstanding the restrictions due to the 2020 health situation. The company’s work did not end with the delivery, installation, testing and commissioning of the plant and compressors, but is also continuing with the plant's operation and remote monitoring, using the latest technology systems.
Commencing in August 2021, an LNG carrier fuelled the plant with LNG, which enabled the tuning activities to be carried out. The plant entered into operation in October 2021. The company will continue its commitment at the LNG storage facility, supervising the maintenance and performance evaluation of the BOG compressors and the reliquefaction plant, consolidating a lasting partnership with DIG, and contributing to the sustainability of sea and land transport in the Adriatic area.
Read the article online at: https://www.hydrocarbonengineering.com/gas-processing/19112021/siad-mi-starts-bog-management-at-lng-storage-facility-in-italy/