Shipyards Strive to Reduce Carbon Emissions

Kuang Zhanting

While vigorously carrying out the R&D and construction of green ships in recent years, China's shipbuilding industry enterprises have been waging a critical battle of containing COVID-19,actively planning the low-carbon development route, creating a green manufacturing system, and building“green factories”, and contributing to the realization of the “double carbon”goal.

Varous tactics

In view of the characteristics of carbon emission reduction in the shipbuilding industry, many enterprises have carried out different explorations on carbon emission control according to local conditions. China State Shipbuilding Corporation (CSSC) has implemented the concept of “energy saving first, green leading”, and adopted the comprehensive governance model of “source - control - end”for carbon emission control. The group has organized and implemented a three-year special action plan for environmental protection, carried out VOCs system investigation,realized the pollutant standard and compliance discharge, and overall improved the pollution control capacity of its subordinate enterprises. The environmental protection governance of CSSC Jiangnan Shipbuilding focuses on the whole production process of specific ship products,combines the environmental protection transformation with the products under construction, and carries out the research of “Green key process system integration project of new VLGC and LNG series liquefied gas vessels”. The company has established a systematic process technology and support capability system around the green integrated systematic verification and efficiency improvement goal of specific ship types.After three years of environmental protection transformation and building,green standard formulation and green factory declaration, the overall acceptance target of the project was finally achieved on schedule, creating a number of first in the industry.

Through the project, Jiangnan Shipbuilding has carried out a series of energy saving and environmental protection technology transformation,such as VOCs governance, energy saving transformation of street lamps,waste heat recovery and reuse of air compressor, and established a systematic process technology architecture for the green integration project. On this basis, the project team prepared the technology design guidelines for VOCs waste gas treatment of steel pretreatment line for large liquefied gas carriers, the technology design guidelines for VOCs waste gas treatment of sectional coating of large liquefied gas carriers and the indicator system for environmental protection benchmarking enterprises for large liquefied gas carriers among other first-batch green manufacturing waste gas treatment technology related specifications.

The exploration of carbon emission reduction by CSSC GSI focused on the building of a “green factory”. The company seized the key link problem tackling, actively explored reduction in the source of hazardous waste,developed electronic ratio doublecomponent large-package “green spraying system” and pentane cutting technology among a batch of advanced demonstration green technologies. They comprehensively applied ultra-high pressure water rust removal equipment, built the first distributed waste treatment plant in the industry, developed hardware and software of mobile control devices for unorganized VOCs emissions,safety and environmental protection intelligent control platform, advanced the large-package coating application,green supply chain management and ecological protection of the Longxue Mountain. From 2019 to September this year, GSI achieved a cumulative reduction in carbon emission intensity and total carbon emission by 38.5% and 8.1% respectively, and it is estimated that the carbon emission intensity by the end of 2023 will decrease by nearly 50% compared with that before the treatment.

Governance of pain points pays off

Aiming at the key links of ship production and the pain points of emission control, Chinese shipbuilding enterprises have achieved results in the R&D and application of carbon emission reduction related equipment and technology.

For ship enterprises with large energy consumption, the indirect carbon emission in the process of ship construction is mainly the power consumption, and adjusting the power source structure is an effective means to achieve carbon emission reduction.“CSSC Shanghai Waigaoqiao Shipyard Phase I 2.8MW rooftop distributed photovoltaic power station project” is a typical case of building environmentally friendly power.Through the development of digital onestop distributed PV solutions, CSSC No.9 Institute made PV power stations smarter and simpler, and promoted both the power generation and operation and maintenance efficiency of distributed power stations. After grid connection,its average annual generating capacity amoounted to about 2.6546 million KWH, the whole life cycle (25 years)will produce about 66.3639 million KWH green power, can save 800 TCE per year, reduce emissions of about 2000t carbon dioxide, offering obvious environmental benefits and economic benefits, expected to effectively help Waigaoqiao Shipbuilding tap new sources of revenue and husband existing resources, and build green low carbon industry ecosystem.

Apart from applying PV power generation to reduce indirect carbon emissions caused by power consumption, Chinese shipbuilding enterprises tried different ways to reduce the proportion of fossil fuels and reduce direct carbon emissions in the production process. For example,Yangzhou COSCO Shipping Industries recently applied AMPS to provide power supply for ships under construction,and has successively installed 16 sets of mobile and fixed shore power devices, with a total capacity of 8120 kVA, becoming the enterprise with the largest shore power capacity in Yangzhou. After the operation, the annual use of diesel oil can be reduced by 3,200 tons, the replacement electricity will reach 15 million KWH,and the cumulative emissions of carbon dioxide, sulfur dioxide, and nitrogen oxides will be reduced by 13,130 tons,940 tons and 1,060 tons respectively.

In view of the relatively concentrated VOCs problem in the painting workshop, ship enterprises also have their own coping strategies.According to statistics, hazardous waste and VOCs generated by the coating operation account for more than 80% of the total production process of the ship enterprise. However, the green spraying equipment and process technology were monopolized by foreign countries for a long time, leading to the high price and maintenance cost of related equipment.GSI in collaboration with CSSC Changjiang Technology has developed the electronic ratio two-component large-package “green spraying system”, which broke the monopoly of foreign enterprises and reduced the equipment price and its application cost by more than 30%. Nantong COSCO Shipping Kawasaki Shipyard (NACKS)carried out VOCs deep treatment and transformation of the coating workshop,and uses environment-friendly coatings to control from the source.China Merchants Jinling Shipbuilding(Nanjing) Co., Ltd. carried out VOCs treatment of the coating room and environment-friendly transformation of VOCs on the pretreatment assembly line.

Top-level design for improved reduction route

In order to strengthen the toplevel planning, CSSC has studied and formulated the carbon emission accounting method and survey plan for the shipbuilding industry,comprehensively carried out the carbon emission survey, sorted out the key emission sources, calculated the carbon dioxide emissions, conducted indepth research on the carbon peaking and carbon neutrality combined with the characteristics of the industry,and promoted the “double carbon”work process in an orderly manner.CSSC No.714 Institute as an energy saving and green development support institution undertook the “Study for roadmap and implementation plan of carbon peaking and carbon neutrality technology for the shipbuilding industry” and a number of other national major projects, the developed“Big-data-based smart energy control information system for shipbuilding enterprises” was incorproated into the“Category recommended for national industrial energy saving technologies”,led to complete the “Technical specification for energy saving diagnosis of the shipbuilding industry” and“Carbon emissions accounting and reporting requirents for builders and repairers of ships and offshore engineering equipment” among other industrial green low carbon standards.

Among them, the exposure draft for “Carbon emissions accounting and reporting requirents for builders and repairers of ships and offshore engineering equipment” has been prepared for public comment, which began to solicit opinions from relevant units in July this year. The standard stipulates the terms, accounting boundaries, accounting steps and accounting methods, data quality management, report content and format of the said rquirements. Enterprises engaged in shipbuilding and repair,manufacturing of steel structure and customs inspection engineering equipment in China can calculate the carbon emissions of the enterprise according to the methods provided in the document, and prepare its carbon emission report thereupon. This document is also applicable to marine low-speed engine manufacturers.

In addition, by GSI involved cooperation, “Saving material evaluation indicator system for ship production enterprises”, “Steel use evaluation and control requirements for ship production enterprises”, “Green shipbuilding evaluation indicator system and evaluation methods for ship production enterprises”,“Design standard for environmental protection facilities of shipbuilding engineering project” and “Wastefree plant evaluation indicator system and evaluation methods”, etc., as well as the first welding material green standard in the shipbuilding industry prepared by Jiangnan Shipbuilding-- “Technical specification for green design product evaluation: low temperature steel welding consumables for liquefied gas carriers” and many other green environmental protection standards are gradually improving the carbon emission standard system of the shipbuilding industry in China.

Industry insiders vowed to give a big push to carbon emission reduction,help achieve the “double carbon”goal, ship enterprises have a lot to do, such as the elimination of high emission equipment, the application of innovative environmental protection technology, carry out emission reduction effect assessment, gradually achieve near zero emissions, net zero emissions,and even gradually build a negative emission technology system.