The Analysis of the Conceptual Framework of Green Port Implementation in Indonesia Using Circular Economy: The Case Study of Benoa Public and Fishing Terminals

Abstract

Several public seaports and fishing terminals are located in the same port complex but have different fragmented operations such as waste management. It is possible to provide a new initiative to ensure sustainability for all entities in the surrounding port ecosystem through the application of Green Port using the circular economy approach and mixed linear programming model. Therefore, this study aims to explore the collaborative management of waste generated from different port activities such as the operators of the public seaport, fishing terminal, and a city authority in Bali–Indonesia using circular economy principles. It was discovered that the integration model has the potential to generate new energy by recycling waste from all related entities in the production of a few main fishing products such as tuna, sardine, and squid, as well as vessel traffic, facilities, and cargo flow interactions in addition to other port operations.

1. Introduction

The port and fishing industry is currently transiting from the era of technology-driven to value-driven systems, as indicated by the focus on sustainable development through the application of Green Port operation to protect the marine environment and work in line with the scarcity of limited resources [1,2,3]. This is observed to be in line with the 17 sustainable development goals developed to promote prosperity, prevent further environmental damage, and ensure sustainable earth. This is known as a circular economy and the main objective is to have sustainable manufacturing with optimum production by reducing the exploitation of natural resources and producing at minimum pollution, emissions, and waste. The concept is also based on refurbishment, repair, remanufacturing, waste processing, and reusing existing products and components that every “waste” becomes an asset and no value goes unrecovered [4,5]. There are four principles of circular economy and these include minimizing waste, using renewables, studying the feedback loop to optimize production, and maximizing the usage value of products [6]. It also advocates the reduction of energy needs, application of alternative energy sources such as solar, wind, and biomass, as well as waste-derived energy utilization of by-products from processing plants [7].

Port has become an important area requiring environmental and sustainable development and this is the reason for the implementation of the “Green Port” which is an environmentally friendly port that prioritizes sustainable and environmental functions [8]. In recent years, numerous attention has been focused on minimizing the impact of port activities on the surrounding environment through the introduction of the latest technology in order to achieve “green” status [9]. The term “Green Port” and its underlying concepts have been used since the early 1990s [10]. It was considered a new approach to realizing sustainable development (at ports) in the late 1990s to 2000s by coordinating the balance between environmental effects and economic benefits [11]. The main idea is to ensure low resource consumption, small environmental impact, good growth mode, and a strong scale effect [12]. This is in accordance with the statement of Kirchherr et al. (2017) [13] that a circular economy aims to contribute to sustainable development.

In Benoa–Bali Indonesia, the public seaport and fishing terminal are in the same area which is owned and managed by a state company such that the fishing, general, and containerized cargo as well as the passengers and cruise traffic are being managed together through the Benoa Maritime Tourism Hub (BMTH). The activities of the fishing terminal mostly involve fish processing plants while the public terminal users are ship operators, passengers, visitors, tourists, and logistics operators. It is important to note that the activities of both sections generate a significant quantity of waste.

The solid and liquid waste generated from the operations of these terminals are considered to be challenging for the management and those from the two different terminals were observed to be managed independently as indicated in Figure 1. This means that the management process applied in the fishing terminal cannot be benefited by the public terminal and vice versa due to the existence of different vessel traffic managed by the operators in the same location. It is important to reiterate that the operations of the public terminal are mostly related to the passengers such as the cruise, container, or cargo ship while the fishing terminal operates the fishing vessel and products and these functions reflect in their main buildings. Some of these operations are located side by side but there is no integration of ecosystem in their activities.

The appropriate treatment and management of the solid and liquid waste generated in this area can provide benefits for every entity in the port ecosystem including the terminals and the city of Denpasar. Therefore, this study proposes a new initiative involving the integration of waste management as part of the ecosystem in the fishing and public terminals as well as the city of Denpasar through the implementation of the circular economy model. The model is also combined with the traffic operational system applied in the three entities, specifically in relation to the waste management flow.

2. Case Study: Benoa Fishing Terminal

The BFT located on the southern tip of Bali Island is part of the Bali maritime tourism hub port established to combine the tourism and fisheries sectors. Bali is often awarded as the best island in the world in the tourism sector because of its unique natural, cultural and sociocultural beauty [14]. Meanwhile, the fisheries aspect is associated with the status of the Benoa area as the locus of consolidation for the national marine management space, specifically concerning the capture of fishes which historically and factually made the area the choice for fishery processing businesses. Benoa port is strategically located between three fishing zones in Indonesia, including the WPP 712, WPP 713, and WPP 573, thereby increasing the connectivity of the fishery products from the Eastern to the Western part of the country and internationally.

The integration of the two sectors is difficult considering the fact that the fishing industry has an unpleasant smell which is very bad for the tourism industry. The foul odor is attached to the improper treatment of the fishing industry, which led to the production of waste, polluting the surrounding environment [15]. In addition to the bad view, this is creating a huge problem for the tourism sector, and this is the reason this study focuses on providing a solution by classifying each waste and its treatment option through the calculation of the quantity and type of the waste generated. This is in line with the recommendation of a previous study that the efforts to manage waste need to be redirected toward reduction, recycling, and treatment techniques to use waste as resources [16].

3. Literature Review

3.1. Circular Economy in Port and Fishery Aquaculture Waste

Studies on ports and their acceleration towards a circular economy are limited [17] even though the concept is closely related to sustainable development and management of ports including their ecosystem such as the operators, fishermen, fishing industries, environment, and the local community. The correlation between society and the port ecosystem developed through a circular economy has been studied [18]. It was discovered that the approach has the ability to provide economic, social, and environmental benefits by promoting its implementation for port operators, users, and surrounding cities to ensure a win–win scenario for several parties. Furthermore, the protection of the port environment including the fishing operations has become an important concern for planners and the increasing awareness concerning sustainable ports has led to its global acceptance and implementation, even in sea and fishing ports. This is observed in the visions set out in Europe toward transiting to the circular economy, as indicated in the following

Table 1. European Port Circular Economy Strategy.

Ports	Existing Circular and Bio-Based Economy Clusters	Strategies
Rotterdam	Renewable energy clusters	Towards 2030 Rotterdam
Antwerp	E-waste and recycling
Zeeland	Bio-park	Sustainable Development Strategy
Ghent	Bio-refinery, bio-park
Amsterdam	Recycling	Vision 2030 and Circle city scan
Ostend	Recycle, recover
Brussels	Recycling hub
North Sea Port	Energy hub; reduce, recycle

Source: [1,22].

, but several fragmentations have been reported in their implementation processes [19,20,21].

Studies also mentioned the application of circular economy in the fishery and aquaculture waste industry. For example, Corral et al. (2022) [23] converted galicia aquaculture waste into revalorized by-products while Zilia et al. (2021) [24] changed sea urchin waste into collagen to produce biomedical devices, dermal implants, cosmetics, and pharmaceutical products. Another example in the fishery industry is the conversion of food waste and by-products to replace fish meal [25]. Moreover, the implementation of a circular economy to ensure waste is reused to produce biomaterials or energy sources is also a method of maximizing the value of production and reducing the quantity of waste to be disposed of [26].

3.2. Framework of Circular Economy in the Public Terminal, Fishing Terminal, and City Authority

Figure 2 shows a framework of the circular economy involving the public terminal, fishing terminal, and city of Denpasar which is expected to be implemented by maintaining the 3R principles of Reduce, Reuse, and Recycle. It is important to note that the liquid waste from fish processing activity can be reused after being treated while vessel parking management can be used to ensure the safety of vessel traffic and increase the efficiency of fish landing. Moreover, it is possible to regulate the activities of fishermen toward recycling their fishing gears, implement reusable products around public terminals, and ensure terminal operators provide an adequate location for street/stand vendors. Every waste generated from surrounding activities can also be recycled by the port and city management instead of transporting them directly to landfills in order to provide certain benefits for both the entities of the port and the city. It is important to note that the current waste disposal system in Denpasar City is in the form of a landfill.

3.3. Waste Management Based Distribution Benefit Approach

The management of waste based on the distribution method involves the processing of waste to produce recycled and reusable products and renewable energy for the benefit of all involved entities. An example of this is the conversion of waste into renewable energy to be distributed to entities generating this waste such as the fish processing operators, port operators, fishermen, and the residents of Denpasar City. It is important to note that some studies have been conducted on the processing of waste and the distribution of their benefits to all parties involved [16,24].

One of the most important environmental contamination sources is industrial waste, such as the by-products of the fish processing plant, in this case [27,28]. This is indicated by the analysis of a previous study, which showed that the quality and quantity of the wastewater produced by XYZ fish processing company is beyond the acceptable standard [29]. This makes it important to explore the appropriate management strategies for fish waste considering their potential as fish feeds as well as others such as biodiesel, chitosan, gelatin, fish oil, jewelry, flavor, and fertilizer [30,31]. Previous studies developed several methods to convert this waste into useful products [32].

Benoa Fishing Terminal (BFT) was combined with a port complex to serve as a hub-port for both tourism and fishing industries, specifically in relation to Eastern Indonesian fisheries. The port has three main fishing commodities including tuna, sardine, and squid, which have always dominated both the export and domestic markets annually (BKIPM Benoa, 2017–2021). These products generate both solid and liquid waste, which need to be analyzed to determine their possible response to the implementation of a circular economy in BFT. It is important to note that the solid waste normally generated from fish and squid processing produces different by-products, and this means they need to be discussed separately while the liquid waste is the same.

Solid by-products during fish processing generally include the head, skin, viscera, and bones, which are usually made into fish meal or fertilizer [33]. According to Vatria (2020) [31], the percentage by weight of the physical composition of fish is 21% head, 7% intestine, 5% liver, 14% bone, 10% fin, 3% skin, 36% meat (fillet), and 4% for others. This agrees with the findings of Babbit (1990) [34] that the weight of fish waste or by-products during the fish processing is approximately 50% of the total weight of the fish, while the solid waste is 4–5% skin, 21–25% head, and 24–34% bone for whitefish and solid waste of 40–45% total for fatty fish [35]. The other main product is squid and its parts mainly used include the fins, mantle, and tentacles while others such as viscera, head, skin, and pen are generally categorized as waste [36]. The weight of this waste is between 22–50% of the total [37]. Meanwhile, 1 ton of squid waste contains 7 kg of pen, 4 kg of ink, 589 kg of internal organs, and 65 kg of skin when it is processed properly. It is also important to note that the squid ink waste was estimated to be 1.3% of the total weight [38] and it is composed of 15% melanin and 5–8% protein as well as free amino acids consisting of taurine, glutamate, and tyrosine [38,39,40]. A previous study also showed that 1 ton of squid waste contains 0.6 kg melanin, 16.4 kg collagen, 46.1 kg biodiesel, and 1.45 kg chitin [36] while squid pens have 42.5% protein [41]. A whole squid waste including the ink, pen, skin, and viscera can easily be directly processed to produce squid liquid fertilizer such that 946 L can be obtained from 1 ton of the waste [36].

It was previously stated that liquid waste from fish and squid processing is the same. The fishery product processing industry consumes water up to 20 m³/ton of product produced depending on the technology used, the type of fish processed, and the product [42]. It was also explained by Overseas Fishery Cooperation Foundation (1987) that liquid waste is mostly generated from four fishery processing activities, including freezing, general processing, canning, and fish meal/oil. Meanwhile, most of the activities at the Benoa fishing terminal are based on freezing and general processing, which produce 14.9 m³/hour of liquid waste. This is different from solid waste, which is based on the product being processed, and this is the reason the determination of the quantity generated from tuna and squid requires different approaches.

3.4. Domestic Waste Management

This study analyzed two types of domestic waste, including solid and liquid. Some previous studies showed that the solid waste in BFT is mainly obtained from two sources, which include the vessels and activities at terminals, while the liquid waste is from the supporting activities.

The solid waste from the vessels is due to the operational activities, while those from the terminals are associated with land installations, facilities, infrastructure, and fish processing plants at the BFT [43,44]. It is also important to note that this waste varies based on the different activities being conducted in the vessels and they include general, hazardous, and kitchen waste separated based on an international classification established by the Annex V of the MARPOL Convention 1973/1978. The volume of the waste mostly depends on the size, gross tonnage, number of crew on board, and the duration of the voyage. Meanwhile, those from the port activities usually come from the industries and buildings in the port area such as canteens, markets, offices or stores, restaurants, and others. Studies on the solid waste generated by vessels are very few and every approach used in the analysis produces different results, but the average in each vessel was found to be 3.06 kg per person per day [45,46,47]. Moreover, three Wastewater Treatment Plants (WWTPs) facility was planned to be constructed at BFT, with one designed to treat wastewater from the fishery processing plants. It was discovered that they are currently able to handle the constantly varying quantities and concentration of wastewater produced daily [48], leading to the production of sludge which is an avoidable problem. This sludge contains a fair number of different contaminants that can produce substances considered to be harmful to health when they are not handled and disposed of properly [49].

3.5. Bilge Waste Management

It has been discovered that approximately 1-2% of the heavy fuel oil burned in a vessel’s main engine and generators ends up as a sludge (Interpol, 2007). It is preferable to recycle the sludge with a low solid concentration of less than 30% and a high oil concentration above 50% [50]. Meanwhile, it was suggested in another study that those with a low oil concentration of less than 10% are also eligible for oil recovery treatment [51].

4. Methodologies

Figure 3 shows the framework of this study, which involves the application of a circular economy to waste generated from port activities, including the fishing aspect and all other operational activities in order to create an environmentally friendly port and promote sustainable development. This is believed to be in line with the plan to realize a Green Port in BFT. Therefore, a quantitative approach was used to analyze the potential of applying a circular economy in managing waste at the BFT. This was focused on determining the activities with the potential to generate waste and the quantity in order to separate them based on type or group.

First, the activities generating waste in BFT, including the Benoa fishing vessel traffic, BFT area, and Benoa fishery export/domestic traffic, were classified. It is important to note that the focus on Benoa fishery export/domestic traffic was based on those generated during the fishery product processing in the plant. Second, the waste was separated into five types, including the oily bilge, domestic solid, liquid, fish solid, and squid solid, which were further categorized into two general groups of solid and liquid waste. It is important to note that not all solid waste can be combined such that the domestic solid waste was separated from fishery by-product waste because aquaculture and related industries process waste have significant risk to the ecosystem, and this means they needed to be handled separately [52]. The squid by-products were also separated from those of the normal fish because some types of squid release a strong offensive odor when decaying [53]. Moreover, the oily bilge liquid waste also needed to be separated from domestic liquid waste in line with the suggestion of Bourguignon (2015) [54] that oil waste is to be collected and treated separately. Third, the treatment to be used for each of this waste was selected based on the quantity generated.

4.1. Waste-Generating Activities

4.1.1. Fishing Vessel Traffic at Benoa Fishing Terminal

The fishing vessel traffics at BFT is divided into four groups based on the size of the vessels and these include 0–30 GT (Gross Tonnage), 31–60 GT, 61–200 GT, and above 200 GT. The information on the fishing vessel traffic in BFT including the number of crew, sailing duration, and calls per week are presented in

Table 2. Fishing Vessel Traffic at Benoa Fishing Terminal.

Vessel Size	Crew Number (Person)	Voyage Duration (Days)	Call per Week	Engine Power (kW)
0–30 GT	5	53	8	123
31–60 GT	7	102	10	200
61–200 GT	7	102	26	460
>200 GT	16	136	2	700

Source: Author Elaboration.

based on each group. It was discovered that the number of crew in each group was assumed to be five on 0–30 GT, seven on 31–60 GT and 61–200 GT, and 16 on those above 200 GT in accordance with the applicable rules which required a minimum of four for ships under 24 m, 6 for 24–45 m and 10 or those above 45 m [55]. Meanwhile, the sailing duration was discovered to be 53 days, 102 days, and 136 days, respectively [55] and the number of vessel calls per week is eight calls on 0–30 GT, 10 on 31–60 GT, 21 on 61–200 GT, and 2 on those above 200 GT. The engine power was also assumed to be 123 kW, 200 kW, 460 kW, and 700 kW respectively for each group based on the approach used in Fabrizio (2015) [55].

4.1.2. Benoa Fishing Port Area

The areas analyzed in this study include the existing Benoa zone and the dumping zone 1. The existing Benoa zone covers the passenger terminal, daily cruise, daily cruise hall, yacht terminal, country’s ship, MSME, food court, iconic monument, amphitheater, mangrove museum, public activity, and terminal hop-on–hop-off. Meanwhile, the dumping zone 1 area includes the retail area, clubhouse, sports center, fish market, as well as the dry and wet berths, as indicated in the following

Table 3. Benoa Fishing Port Area.

No	Building Name	Capacity (People)	Area (m2)	No	Building Name	Capacity (People)	Area (m2)
Existing Benoa Zone				Dumping 1 Zone
1	Passenger Terminal	3040	9000	A	Retail Area	8062	9674
2	Daily Cruise	1914	2872	B	Club House Area
3	Hall Daily Cruise	5915	8873		Lounge Entrance Club House	381	1524
4	Yacht Terminal	67	267		Restaurant	297	1947
5	Country’s Ship	500	1024		Café	54	323
6	UMKM	3000	30,260		Private Inn Clubhouse	153	1500
7	Foodcourt	2522	5153		Main Club House	11,618	17,426
8	Monument Icon	100	6030		Lounge and Bar	205	1231
9	Amphitheater	10,000	15,845	C	Sport Center Area	2038	3975
10	Mangrove Museum	441	3537	D	Fish Market Area	3353	14,116
11	Public Facility	1026	2215	E	Area Dry and Wet Berth
12	Terminal hop on hop off	309	2060	1	Dry berth	5773
				2	Wet berth	10,450

Source: Pelindo III, 2021.

.

4.1.3. Benoa Fishery Export/Domestic Traffic

The fishery products analyzed include the pelagic fish (tuna and sardine) and squid with the total export volume in 2020 recorded to be 29,886 tons such that tuna contributed 9136, sardine 2335, and squid 7234. Meanwhile, the domestic volume was found to be 172 tons, including 43 for tuna, 3 for sardines, and 1 for squid.

4.2. Waste Generated and Separation

4.2.1. Oily Bilge Waste

The sizes of oily waste tanks are regulated in MEPC 54/21 concerning the revised guidelines for systems of handling oily waste in machinery spaces of ships incorporating guidance notes for an integrated bilge water treatment system. Meanwhile,

Table 4. Capacity of Drain and Leakage Oil Tank and Bilge Water Holding Tank.

Type	Main Engine Rating (kW)	Capacity (m3)
Capacity of Drain and Leakage Oil Tank	Up to 10,000	20 × D × P/106
	Above 10,000	D × (0.2 + 7 × (P − 10,000)/106
Capacity of Bilge Water Holding Tank	Up to 1000	1.5
	1000–20,000	1.5 + (P − 1000)/1500
	Above 20,000	14.2 + 0.2 (P − 20,000)/1500

Source: IMO, 2006. Where D = days; the same length of the voyage. P = main engine rating in kW.

presents the recommended capacity for the drain leakage oil tank and bilge water holding tanks (IMO, 2006).

The oily bilge waste generated from the vessel traffic per day was calculated as follows:

$${\mathrm{OW}}_{\mathrm{i}}=\frac{20\times {\mathrm{P}}_{\mathrm{i}}\times {\mathrm{T}}_{\mathrm{i}}\times {\mathrm{N}}_{\mathrm{i}}}{1000000\times 7}+\frac{1.5\times {\mathrm{N}}_{\mathrm{i}}}{7}$$

(1)

where:

• OW_i = Oily bilge waste generated by vessel size i per day (m³)
• P_i = Main engine ratin of vessel i (kW)
• T_i = Total voyage duration per vessel size i (days)
• N_i = Number of call vessel size i per week

4.2.2. Domestic Solid Waste

Domestic Solid Waste Generated from Vessel Traffic

The solid waste generated from the vessel traffic per day was determined using the following formula:

$${\mathrm{SW}}_{\mathrm{i}}=\frac{{\mathrm{C}}_{\mathrm{SW}}\times {\mathrm{Cr}}_{\mathrm{i}}\times {\mathrm{T}}_{\mathrm{i}}\times {\mathrm{N}}_{\mathrm{i}}}{\mathsf{\rho }\times 1000\times 7}$$

(2)

where:

• SW_i = Solid waste generated by vessel size i per day (m³)
• C_SW = Quantity of the solid waste generated per person per day: 3.06 kg/person/day
• Cr_i = Number of Crew per vessel size i (person)
• T_i = Total voyage duration per vessel size i (days)
• N_i = Number of call vessel size i per week
• $\mathsf{\rho }$ = Solid waste density: 0.38958 ton/m³ [56]

Domestic Solid Waste Generated from Benoa Fishing Port Area

Kemenperin (2017) estimated solid waste generated to be 4 m³/hectare/day, while different standards were used for those from other activities. It was discovered that households produce 2.5 L of waste/day and the market for domestic/daily product have as much waste as 25% of household waste, roads have 10%, and others are assumed to be 5%.

4.2.3. Liquid Waste

The liquid waste analyzed in this study was those from the fish processing plant and the quantity generated is presented in

Table 5. Capacity of Drain and Leakage Oil Tank and Bilge Water Holding Tank.

Type	Frozen	General Processing	Canned	Pallet Fish/Fish Oil
Number of Facilities	25	136	6	11
Product processing (ton/day)	725	983	161	325
Water needed for processing (m3/day)	11.25	15.17	868	3.09
Wastewater generated (m3/day)	10.83	14.62	858	3.07
Number of liquid waste per ton product (m3)	14.9	14.9	5.3	9.4

Source: Overseas Fishery Cooperation Foundation, 1987.

(Overseas fishery cooperation foundation, 1987). The majority of plants in the Benoa fisheries zone are cold storage, and their liquid waste is assumed to be 14.9 m³/ton of products.

The liquid waste generated from the fish processing plant per day was determined using the following equation:

$${\mathrm{LW}}_1=\mathsf{\Sigma }\frac{{\mathrm{C}}_{\mathrm{LW}}\times {\mathrm{M}}_{\mathrm{j}}}{365}$$

(3)

where:

• LW₁ = Liquid waste generated from fish processing activity per day
• C_LW = Liquid waste generated per ton of product: 14.9 m³/ton
• M_j = Total traffic of product j per year (ton)

4.2.4. Fish and Squid Solid Waste Product

The solid waste generated from fish and squid product per day was determined using the following formula:

$${\mathrm{SW}}_{\mathrm{i}}=\mathsf{\Sigma }\frac{{\mathrm{M}}_{\mathrm{j},\mathrm{k}}\times {\mathrm{C}}_{\mathrm{j}}}{365\times \mathsf{\rho }}$$

(4)

where:

• SW = Total of solid waste generated by product j
• M_j,k = Total of traffic k per year of product j (ton)
• C_j = Percentage of by-product generated by product j

5. Result

5.1. The Waste from Benoa Fishing Vessel Traffic

Equations (1) and (2) were used to calculate the oily bilge and domestic solid waste from Benoa fishing vessel traffic. Figure 4 shows the number of domestic solid waste and oily bilge waste generated per day from the number of total GT per week. In more detail, it was discovered that the domestic solid waste generated from 0–30 GT, 31–60 GT, 61–200 GT, and vessels above 200 GT were 2.38 m³, 8.01 m³, 20.83 m³, and 4.88 m³, while the oily bilge waste was 1.86 m³, 2.73 m³, 9.06 m³, and 0.97 m³, respectively. This means the total quantity of domestic solid waste from these vessels per day was 36.1 m³ and the oily bilge waste was 14.62 m³.

5.2. Domestic Solid Waste from Benoa Fishing Port Area

Domestic solid waste was determined using the formula from Kemenperin (2017). The results presented in

Table 6. Solid Waste Generated per Day from Benoa Fishing Port Area.

No	Building Name	Area (m2)	Waste (m3)	No	Building Name	Area (m2)	Waste (m3)
	Dumping 1 Zone
1	Passenger Terminal	9000	3.6	A	Retail Area	9674	0.301
2	Daily Cruise	2872	1.148	B	Club House Area
3	Hall Daily Cruise	8873	3.549		Lounge Entrance Club House	1524	0.013
4	Yacht Terminal	267	0.106		Restaurant	1947	0.01
5	Country’s Ship	1024	4.09		Café	323	0.002
6	UMKM	30,260	0.113		Private Inn Clubhouse	1500	0.099
7	Food-court	5153	0.094		Main Club House	17,426	0.435
8	Monument Icon	6030	0.003		Lounge and Bar	1231	0.007
9	Amphitheater	15,845	0.375	C	Sport Center Area	3975	0.253
10	Mangrove Museum	3537	0.05	D	Fish Market Area	14,116	5.646
11	Public Facility	2215	0.037	E	Area Dry Berth Wet Berth		2.309
12	Terminal hop on hop off	2060	0.012	1	Dryberth		4.18
				2	Wetberth
Total Waste Generation from Existing Benoa Zone			9.5	Total Waste Generation from Dumping 1 Zone			18.91

Source: Author Elaboration.

show that the total generated per day from the existing Benoa zone was 9.5 m³ while the dumping 1 zone produced 18.91 m³, thereby making a total of 28.41 m³ from the Benoa fishing port area.

5.3. Waste from Fish Processing Plant

The fish processing plant generated both the liquid and solid waste with the liquid ones observed in this study to be from the fish processing activity, while the solid ones are the by-products of pelagic fish and squid. Equations (3) and (4) were used to determine the quantity of this waste. The results presented in

Table 7. Waste generated from Fish Processing Plant per day.

Product	Export and Domestic Traffic per Year (ton)	Solid Waste (m3)	Liquid Waste (m3)
Squid	7325	4.415	299
Tuna and Sardine	11,517	4.417	470.1
Total			769.1

Source: Fish Quarantine Agency, Quality Control and Safety of Fishery Products, 2021.

show that the squid produced 4.415 m³ of solid waste per day and the fishes have 4.417 m³, while the total liquid waste generated per day was 769 m³.

6. Discussion

6.1. Benefit Distribution of Recycling Energy Based on Circular Economy

The results showed that the waste generated per day in BFT for solid including domestic, squid, and fish is 64.51 m³, 4.415 m³, and 4.417 m³, respectively, while for liquid, it was 769.1 m³, and 14.62 m³ for oily bilge. The proposed flow of integrated waste management practices at BFT and every entity involved is presented in Figure 5. Moreover, it was discovered that the fish by-product can be used as fish meal or fertilizer and squid by-product can be transformed into melanin, chitin, fertilizer, and biodiesel, while the liquid waste from processing activities needs to go through wastewater treatment installation before they are discharged into the sea.

The calculations also estimated the wastewater treatment installation to have the capacity of handling 769.1 m³ of wastewater per day. Moreover, the oily bilge water is designed to be first stored at the bilge holding tank in the terminal, which is capable of handling approximately 14.62 m³ per day. The oil is expected to be treated to ensure it is less than five ppm before being discharged at sea while the sludge is placed in the incinerator. Meanwhile, domestic solid waste is designed to pass through the separation facilities to separate organic and recyclable waste from non-recyclable ones. The non-recyclable waste is to be transferred to the incinerator, organic waste to the composting facility, and recyclable waste for further recycling processes.

It was discovered that the waste management flow in BFT has four entities, including the fish processing, port, and fishing port operators, as well as the regional government of Denpasar City. The flow shows that the regional government is expected to provide a waste processing facility to turn the waste into recycled products and renewable energy, while the other three entities are to send waste to this facility regularly. Moreover, the regional government also proposed to have 50% of the benefits for providing the facilities, while the fish processing and port operators have an equal share of 20% because they generate the highest waste.

6.2. Waste Utilization Management

The liquid waste generated from the fish processing activity is to be directed to the wastewater treatment installation, after which the treated water is to be discharged directly into the pond at Benoa park for subsequent watering of vegetation around the Benoa terminal or reuse in the fish processing plant. Meanwhile, the oily bilge waste is designed to be passed to the oily water separator and later discharged to the sea, while the sludge is to be transferred to the incinerator. Domestic solid waste is proposed to be separated into three types, including organic, recyclable, and non-recyclable. Waste that has recyclable value can be sold into the recycling market, non-recyclable waste is sent to the incinerator for electricity, and organic waste will be directed to composting facilities for fertilizer or biogas production. It is also possible to process the fish solid waste using two methods, and these involve the processing of the fish viscera into fertilizer or fish meal to feed the fish at fishpond around the Benoa area as well as the conversion of fishbone into handcraft for tourist souvenirs or calcium supplements. Furthermore, the solid squid waste can be converted into melanin, chitin, collagen, or biodiesel. This means that the efficient and correct management of every waste in BFT is expected to ensure none eventually waste due to reuse, recycling, or transformation to develop the Benoa terminal, specifically with the focus on ensuring the area becomes a tourism hub. The proposed waste management using the circular economy concept is expected to support Benoa as a Green Port.

6.3. Practical Implications

There are new empirical implications due to the future potential applications using circular economy of Benoa Port in Bali namely:

• In order to achieve sustainable development, fishing ports and public ports may be integrated into operation and zones for handling ships and their cargo as long as the process of handling waste and processing fishery products becomes more efficient and productive.
• A circular economy may be used as a theoretical framework of factors determining Green Port implementation for fishing and public ports.
• The variety of handling waste due to the complexity of the types and trends of ship traffic including its cargoes, the type of cargo handled, and its solid and liquid waste have the potential to be a return benefit for fishing and public port operators in Benoa with the City of Denpasar.

7. Conclusions

The integration of fishing and public terminals in the waste management framework using the circular economy was analyzed. The findings showed potential collaboration or a joined process of the fishing terminal, public terminals, and city of Denpasar in Benoa Bali has the potential to be proposed as a conceptual framework in managing waste management problems due to growing vessel traffics and activities of fishing, passenger, and merchant vessels for the implementation of Green Port application.