PT REMBANG BANGUN PERSADA (RBP) is an affiliated company of PT BANGUN ARTA MINERAL, a Surabaya, East Java – based producer of limestone and its derivates. Both companies are members of BANGUN ARTA GROUP, with the former responsible for quarrying activities and the latter for product development and marketing.
Since 2011, RBP has been operating a limestone quarry in the coastal regency of Rembang in northern Central Java. The quarry covers a 38 ha area of karst limestone mountainous terrain, with an elevation of up to 450 meters above sea level, in Tegal Dowo village, Gunem district, approximately 37 km from the downtown of Rembang and accessible by road through the teak forests of state-owned forestry company Perum Perhutani. It is relatively easy to reach Rembang by land as the Jaa northern coastal highway passes through the town, connecting Jakarta in the west with Surabaya in the east.
Based on the appraisal by PT SURVEYOR INDONESIA, the RBP quarry is estimated to contain a hypothetical reserve of up to 33 million tons of limestone deposited down to 30 meters in depth from the surface.
Production and Logistic
The original material of limestone is calcium carbonate (CaCO3), but either before or after its consolidation, dissolved magnesium compounds in water may partly replace the calcium with magnesium forming magnesium carbonate (MgCO3). Based on this characteristic, the RBP limestone is classified as high-grade limestone with greater than 98% CaCO3 and less than 1% MgCO3. This limestone is suitable for calcining in rotary kilns and for making foundry flux, chicken grits, and some type of glass.
The company’s limestone product is primarily sold to the nearby steam power plant (PLTU Tanjung Jati B) in Jepara regency, Central Java under a ten-year contract effective from 2010 through 2020.
In order to support sea delivery services to customers in other markets the company has built a private stockpile and jetty, which occupies a site area of 8,100 square meters at Tanjung Bonang port in Sluke district. The stockpile has a capacity of 35,000 tons and is equipped with a barge loading conveyor, through which the limestone product is loaded directly onto barges with a capacity of 1,000 tons per hour.