Buton Asphalt Languishing in its Homeland
Natural asphalt reserves in Southeast Sulawesi, which is the only natural asphalt-producing region in the archipelago, are reported to be more than 600 million tons.
Hopes of optimizing the country’s own natural resources in road construction have yet to materialize with Buton asphalt still being a second option to petroleum asphalt, even in Southeast Sulawesi, which holds the world's largest reserves of natural asphalt.
Buton Island in Southeast Sulawesi is known for its rich deposit of natural asphalt. However, this great natural gift has not been optimally pursued to cater to the needs for asphalt domestically, even in the province itself.
Natural asphalt reserves in Southeast Sulawesi, which is the only natural asphalt-producing region in the archipelago, are reported to be more than 600 million tons. Accounting for 80 percent of the world's reserves, Buton asphalt can meet the domestic need for hundreds of years to come. Other natural asphalt deposits are found in Trinidad and Tobago, Canada and, to a lesser extent, on the African continent.
Even in the province, Buton asphalt has failed to draw the regional government for its optimal utilization.
Despite the abundant resources, Indonesia has yet to optimize the utilization of Buton asphalt, with it still largely relying on imported petroleum asphalt. Even in the province, Buton asphalt has failed to draw the regional government for its optimal utilization.
In fact, the quality test shows that Buton asphalt is far above petroleum asphalt. In the latest laboratory test to measure asphalt binder performance grade (PG) at the natural resource utilization and Bina Marga office of Southeast Sulawesi, Buton asphalt PG 70 showed a stability value of 1,562.5. This value appeared to be some 200 points above petroleum asphalt 60/70, whose stability was 1.357.
The latest test on the Buton asphalt product was carried out in August, with the result being the same the previous test at the end of last year. Buton PG 70 asphalt is a new product intended for the construction of toll roads, state roads and class III roads. A number of other advanced products are asphalt B 5/20, B 50/30 and cold paving hot mix asphalt (CPHMA).
Laboratory official M. Yansen said on Tuesday (25/10/2022) that the stability level of Buton PG 70 asphalt showed the bitumen’s pressure-resisting capacity. The higher the stability value, the better the resistance to pressure. The lab experiment shows Buton asphalt is of better quality than petroleum asphalt.
He said the test also showed that Buton asphalt matched, even outmatched, petroleum asphalt in term of viscosity.
"From the test, the elasticity reached 145 centimeters in persistent [flow]. We tested it three times and the results were the same. For petroleum asphalt, it was around 135-140 cm, and potentially up to 145 cm, but [the flow] did not persist," he said.
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Laboratory head Wihardjo said the product type experiment had been carried out since 2019 and it hardly had inferiorities to petroleum asphalt or other Buton asphalt variants, except that it required minor technical adjustments in utilization.
“There should be no reason not to use this product for standard-quality roads. While Buton asphalt has been used only as a minor substitution so far, with this new product, it can completely replace [petroleum asphalt]. We have informed the [public works] office of this and will present it to Governor Ali Mazi," he said.
Overlooked option
Given its quantifiable worthiness to replace petroleum asphalt, Buton asphalt’s PG 70 is expected to become an option in road construction. In the province, petroleum asphalt is still being largely used in up to 70 percent of road projects, with the rest using Buton asphalt B 50/30.
Regional Regulation No. 2/2016 on the utilization of Buton asphalt for the construction and maintenance of provincial and regency roads mandates that at least half of the asphalt used in a given construction project is Buton asphalt. Governor Ali Mazi, on several occasions, has also appealed for the use of Buton asphalt but apparently to little effect.
Yudi Masril, head of the provincial Bina Marga road agency, affirmed on Monday (24/10) the dominance of petroleum asphalt over Buton asphalt.
He attributed it to the fact that the available Buton asphalt products did not carry upgraded quality, which prompted the provincial administration to turn to a mix of asphalt B 50/30 with oil asphalt and other aggregates.
He said he had high hopes for Buton asphalt PG 70.
“Buton asphalt is largely being used only in a few areas, including Buton regency.”
In addition to the quality, he said, price competitiveness should also be taken into consideration. Good quality and good price, he added, were expected to enable Bina Marga to stem the obstacles that might arise in road projects.
"Among the projects soon to be realized, we will test [PG 70] on the Kendari-Toronipa road," he said.
Based on data from the Indonesian Buton Asphalt Developer Association (Aspabi), the national asphalt use in 2021 was 888,557 tons.
The minimal use of Buton asphalt in Southeast Sulawesi is also a reflection of its meager capitalization nationally. Based on data from the Indonesian Buton Asphalt Developer Association (Aspabi), the national asphalt use in 2021 was 888,557 tons.
Of that amount, 82.6 percent or 707,324 tons were imports, worth Rp 9.2 trillion. Petroleum asphalt from state oil and gas company PT Pertamina of Cilacap accounted for some 146,527 tons or 16.5 percent. The rest, or 0.9 percent, was contributed by Buton asphalt.
President Joko “Jokowi” Widodo’s recent visit to Buton on 27 Sept. gave a glimmer of hope. While inspecting an asphalt processing plant, the President noted the country’s richness in asphalt, with reserves of around 622 million tons.
Pointing out the need for Buton to improve its scale in supplying the country with asphalt, he said asphalt imports would be stopped in the next two years.
Committed goodwill
Aspabi chairman Dwi Putranto said the country’s sluggishness in the use of Buton asphalt had brought about suboptimal production. He added that for the past few years, asphalt production would only be carried out when there was demand.
He said further that the existing Buton asphalt generally had the quality of PG 70, which was equivalent to the currently widely used polymer petroleum asphalt.
In terms of price, Buton asphalt was not much different from petroleum asphalt, he said. “Buton asphalt, in fact, can be categorized as cheaper than high-quality petroleum asphalt.”
He hoped developers were committed to using Buton asphalt in the future and pointed out the need to step up efforts from upstream to downstream so that problems could be resolved in stages.
Syamsir Nur, head of the Economics School of Halu Oleo University, said the main problem with Buton's asphalt was the lack of government goodwill, saying that production, quality and supply chains were not obstacles to its mass use in the province nicknamed "Bumi Anoa".
He added that economically, the distribution of asphalt should be much cheaper because of the location.
He said the local government should be more committed to using Buton asphalt in road projects. He added that economically, the distribution of asphalt should be much cheaper because of the location.
“In addition to the abundance of [other natural] resources, the maximum use of Buton asphalt will bring a broad impact on the economy, be it investment, job creation or other [positive] impacts on the community. This is a matter of commitment and goodwill," he said.
This article was translated by Musthofid.