The structural and facility characteristics of ships that must be applied at the construction stage vary by their purpose of operation. A training ship must comply with all the legal regulations outlined in the International Maritime Organization (IMO) conventions and domestic laws, including the Ship Safety Act, in order to maintain basic seaworthiness. Additionally, the requirements based on the international convention on Standards of Training, Certification, and Watchkeeping for Seafarers (STCW) and the standards of the designated educational institutions in Republic of Korea should be met simultaneously to meet the educational objectives of the trainees. Therefore, various operational and legal considerations that must be addressed in the construction phase of the training ships to achieve the operational objectives should be studied and analyzed. The considerations that must be reflected in the construction phase should be classified as ship construction characteristics.
For new training ships, the NOX reduction system must be selected after considering the construction scale, main engine, and generator by reflecting the aforementioned ship construction characteristics of training ship.
Moreover, the applicability of newly developed NOX reduction technologies must be verified by onboard testing.
In this study, the characteristics of ship's construction according to the IMO and international and national legislation that must be considered in the building phase of training ships were first investigated and analyzed. The gross tonnage and main specifications of the new training ship were determined by comparing them with those of other existing training ships. The main engine power was determined using a water tank model test, and the generator capacity was determined by calculating the amount of power required for the basic operations of the ship. After reviewing various NOX reduction devices, the low-pressure selective catalytic reduction (LP SCR) system was selected as the NOX reduction device for this generator, and a factory inspection was conducted to ensure compliance with Tiers II and III of the IMO NOX emission standard.
Additionally, the performance of a newly developed NOX reduction system, the Solid SCR system, was evaluated in the training ship; the amount of NOX reduction by load and the amount of NH₃ slip were compared to that of the conventional Urea SCR system. Accordingly, not only did the Solid SCR system have better conformability and reliability to the load variations of the generator and a higher NOX reduction rate, but it also generated a relatively lower amount of NH₃ slip than that by the Urea SCR system.
Before the Solid SCR system can be commercialized for ships, its durability and economic feasibility have to be evaluated. It is believed that this alternative system will have significant ripple effects on NOX reductions in the shipping industry if the results are positive.