Evaluation on the Potential Production of Horizontal Moulding Crystal Clear Ice Block Applying One Direction Heat Absorption I Putu Sastra Negara (1,a), I Nyoman Suamir (1,b), and I Wayan Suirya (1,c)
1) Mechanical Engineering Department, Politeknik Negeri Bali, Jl. Kampus Bukit Jimbaran, Kuta Selatan, Badung-Bali 80364
Author Emails
b) Corresponding author: nyomansuamir[at]pnb.ac.id
a) putusastranegara[at]pnb.ac.id
c) wayansuirya[at]pnb.ac.id
Abstract
The paper presents investigation on a small capacity of horizontal moulding crystal ice block machine. The investigation was motivated by the increasing need for crystal clear ice blocks in Bali as a tourist destination. Therefore, it is necessary to develop a crystal block ice machine that is functional, practical and energy efficient. A lab size ice block machine was developed. This ice machine applies a horizontal moulding with heat absorption in one direction only which conducted by using a refrigeration system with R404A. The heat absorption by the evaporator of the refrigeration system occurred only at the bottom surface of the ice-block moulding. The machine constitutes two horizontal mouldings with capacity of 125 to 150 kg ice per moulding which is equivalent to a thickness of ice formation of 25 to 30 cm. The machine was designed to be able to accommodate refrigeration system of 1 kW and 2.4 kW cooling capacity. The production potential of the horizontal-moulding crystal-clear ice block machine with different cooling capacity was tested and evaluated. The evaluation included ice temperature, ice formation rate, ice production, time of production and energy consumption. The test results showed that the ice formation rate of the machine with 1 kW and 2.4 kW cooling capacity were relatively similar at the level of 10 cm ice depth in the first 24 hours and the formation rate decreasing for about 2 cm in the following 24 hours. It was found that time required to produce 2 crystal ice blocks of 125 to 150 kg was about 3 up to 4 days. The machine with 1 kW cooling capacity continually operated during the production period but the machine with 2.4 kW cooling capacity could operate with frequent cycling on and off. It is also found that the power consumption of the ice machine with lower cooling capacity consume 30 per cent less energy than the machine with higher cooling capacity. This finding has also indicated that optimization on the cooling capacity and the application of secondary refrigerant may reduce the production time and energy use.
Keywords: Horizontal moulding- crystal clear ice block- production capacity- one direction heat absorption
