Characterization and analysis of shopping mall solid waste composition for refuse derived fuel and black soldier fly (case study: X shopping mall in Central Jakarta City)

This study identified and analysed the composition of solid waste generated by retail malls in Central Jakarta City, with a particular emphasis on determining the potential applications of Refuse Derived Fuel (RDF) and Black Soldier Fly (BSF) technologies. The research involved exhaustive waste samplings, taken at various activities within multiple X shopping mall in order to determine the categories and amounts of waste generated. The collected samples were subjected to a thorough analysis to determine the proportion of organic and inorganic refuse and assess their suitability for processing using the RDF and BSF techniques. The investigation revealed that X Shopping Centre’s solid refuse consists primarily of inorganic waste (77.42%) and organic waste (22.58%). Essential waste characteristic analyses were conducted to determine the combustion energy potential of the inorganic waste, yielding a moisture content of 41%, an ash content of 6%, a volatile matter content of 94%, and a calorific value of 10,502 kcal/kg. Using information on waste composition and characteristics, the study investigated the potential use of RDF and BSF technologies to manage and repurpose the generated waste. The RDF processing potential was calculated to be 8.77 tons per day, while the BSF processing potential was 3.11 tons per day. This estimate illustrates the substantial capacity of these technologies to manage and convert large quantities of refuse into valuable resources. In addition, the study assessed the monetary implications of implementing RDF and BSF technologies in the context of X Shopping Mall. The estimated investment required to implement these technologies is 11,198,926,800 IDR.


Introduction
Waste is generated from commercial or trade areas, such as stores, restaurants, markets, retail malls, offices, hotels, printing shops, service units, and workshops.In general, varieties of commercial waste include waste similar to household waste, such as paper, cardboard, plastic, timber, food waste, glass, and metal; electronic devices; garden waste; used tires; used culinary oil; used batteries; hazardous waste; and other waste types.[1].Managers of commercial locations must provide facilities for waste segregation [2].Refuse Derived Fuel (RDF) and Black Soldier Fly (BSF) technologies are among the appropriate waste processing methods that can be determined based on the category of waste.
RDF is a byproduct of the process of separating solid waste into combustible and noncombustible fractions, including metals and glass.It can be used as an additional fuel in industries such as cement and power facilities, thus reducing the waste volume.In the production of RDF, the combustible fraction of waste is typically reduced in size and desiccated so that it can be used as fuel [3].Several parameters, including calorific value, moisture content, ash content, and volatile matter content, must be considered during the waste-to-RDF conversion procedure [4].
The Black Soldier Fly (Hermetia illucens) is one of the insects whose characteristics and nutritional content have been extensively studied [5].It is able to extract energy and nutrients from a variety of sources, including vegetable remnants, food waste, animal carcasses, as well as feces and domestic wastewater [6].

Determination of shopping mall activities
The purpose of determining shopping mall activities is to identify and define the various categories of activities that occur within a shopping mall.This entails classifying and characterizing the various functions and operations within the mall, including retail sales, food and beverage services, entertainment facilities, administrative functions, security measures, and other services provided to visitors and tenants.

Determination of shop samples
The purpose of determining shop samples is to obtain daily waste generation, produced by shopping centers in order to obtain representative results for all shopping centers.

Experiment test of water content, ash content, volatile matter, and calorific value
Shopping Mall waste is compared with the standards used by the Indonesian Cement Association to assess its suitability for Refuse Derive Fuel (RDF).The evaluation is performed on miscellaneous waste, non-valuable plastic, paper, styrofoam, tetrapak carton, and wood.By comparing the test results to the established standards, it is possible to determine which waste streams are most suitable for RDF production and have the potential to contribute to sustainable waste management and energy recovery initiatives.

Determination of waste treatment methods
The objective of Determination of Waste Treatment Methods is to identify and select the most suitable techniques or strategies for managing and disposing of different categories of waste.The available technologies are classified as Refuse Derived Fuel (RDF) and Black Soldier Fly (BSF).

Shop activities and samples
There are various activities taking place in shopping centers, generally categorized into buying and selling, dining, and other types of social activities based on the type of shops.There are 5 categories of shops and 1 public facility available in the shopping center, as summarized in Table 1.In Table 1, based on the calculation made, using Slovin method the results show that, a total of 86 samples of shops are representative from 4478 shops.The waste generation rate of the samples produced was found to be at a rate equivalent to 3.85 kg/day, and this was used to project the amounts produced for all the available stores as can be seen in Table 2.A total of 17.24 tons/day is generated by all the shops in X Shopping Mall.Organic and inorganic waste classified based on their compositions, for the subsequent appropriate waste processing.

Waste compositions
The composition of waste is divided into two types, namely organic and inorganic.The details of which are as in Table 3.Based on Table 3, which show the waste composition proportions, inorganic waste forms the main waste category (77.42%), compared to the organic type (22.58%).Waste that can be processed using RDF technology includes non-valuable inorganic waste such as PP, OPP, PVC, HDPE, and LDPE plastics, paper, styrofoam, tetrapak cartons, as well as hard organic waste including timber.Meanwhile, waste that can be processed using BSF technology include those form for food and other soft organic material.

Waste characterization
Waste characterization is the process of identifying the parameters that need to be considered in processing waste using RDF technology.The parameters identified are, moisture content, ash content, volatile matter content, and calorific value.Based on the laboratory analysis results, the findings can be seen in Tables 4 and 5.The water content parameter in waste processing utilizing Refuse Derived Fuel (RDF) technology, is used to determine the combustion efficacy.The lower the water content value, the greater the calorific value generated, the environmental impact caused, and the type of waste management to be implemented.Low (ideal) water content for RDF alternative fuel, according to the Indonesian Cement Association and Cement Industry (2017) [7], is between 1% and 3.5%, the medium water content is between 36% and 66%, and the high water content is between 66-100%.The average water content obtained in the research was 41%, indicating that the water content test results for the waste from Shopping Center X fell within the category of the medium water content.
In waste processing utilizing Refuse Derived Fuel (RDF) technology, the ash content parameter is used to determine the fuel quality, where the higher the ash content, the greater the non-combustible mineral content, which affect the combustion efficiency, the environmental impact, and the suitability for specific applications.In waste processing with RDF technology, the volatile matter content parameter is used to analyze the combustion efficiency, where, a higher volatile matter content is expected to accelerate the combustion process, affect the fuel's calorific value, adapt to the combustion process, control emissions, and manage waste.According to the Indonesian Cement Association and Cement Industry (2017), the optimal ash content for RDF alternative fuel is between 1% and 30%, while an elevated ash content is greater than 30%.The optimal volatile matter content for RDF fuel is between 70 and 100%, while a minimal volatile matter content is 70%.In the research, the average ash content was determined to be 6%, and the average volatile matter content was found to be 94%, indicating that the ash and volatile matter tests of the refuse from Shopping Center X are within the feasible parameters.
The purpose of calculating the calorific value of a material or substance is to determine the amount of energy released per unit mass or unit volume, when it is completely incinerated.The calorific value calculation was carried out in the Environmental Laboratory of Trisakti University using a bomb calorimeter.According to Regulation of the Ministry of Energy and Mineral Resources No. 047 of 2006 [8], the minimum calorific value standard for Refuse Derived Fuel (RDF) is 4,400 kcal/kg.In waste processing using RDF technology, the calorific value parameter is used to determine energy efficiency, fuel quality, potential utilization, waste reduction, and emission reduction.In the investigation carried out, the average calorific value obtained was 10,502 Kcal/kg, indicating that the waste from Shopping Center X meets the calorific value requirements for RDF.The high calorific value of the refuse from Shopping Center X's refuse demonstrates its potential as a valuable RDF fuel source.With such a high energy content, the refuse can be used effectively as an alternative fuel, contributing to the initiatives taken to generate energy and reduce waste.By utilizing waste as RDF, Shopping Center X can enhance its waste management practices, lessen its environmental impact, and harness the waste's energy potential.

Waste processing method
The waste treatment process for shopping center waste involved the utilization of RDF (Refuse Derived Fuel) and BSF (Black Soldier Fly) technologies.The waste sorted and separated into combustible and noncombustible fractions during the RDF process.The combustible fraction was shredded, screened, and dried out to create RDF, which can be used as an alternative fuel source in a variety of industries, including cement and power plants.This method reduces waste volume and extracts energy from the refuse.In contrast, the BSF method utilizes Black Soldier Fly larvae to digest organic material, such as food scraps.The larvae convert organic material into biomass, which can be utilized as animal feed or organic fertilizer.The BSF procedure contributes to the recycling and reduction of organic waste.Figure 1 depicts the mass equilibrium for the waste management.In determining the mass balance, a recovery factor calculation is needed to determine the stages of the waste treatment process.Recovery factor numbers are defined by dividing the weight of reduced waste by the weight of waste generation (Table 6).In waste processing there are four types of facilities that can support the waste process, namely: pretreatment facilities, RDF facilities, BSF facilities, and supporting facilities.Pre-treatment facilities consist of waste collecting point and waste sorting area.RDF facilities consist of shredding, screening, and drying area.BSF facilities consist of shredding, grow-out bio pond, hatchery bio pond, rearing, hatchery, and product harvesting [10].The supporting facilities include valuable waste storage, residual waste storage, product storage, toilet, office, prayer room, guardhouse, tools storage, and worker rest room.The required building land area is 1,970 m 2, and the estimated cost incurred in adopting these technologies is 11,198,926,800.00IDR.Tables 7, 8, 9, 10, and Figure 2 provide information related to each of the facilities.

Figure 1 .
Figure 1.X shopping mall waste mass balance.

Table 1 .
Shop categories and samples.

Table 4 .
Water content, ash content, and volatile matter.