Conventional rice mills are introduced in this section. In the 1920s, Taiwan introduced mechanical rice mills but they did not become prevalent till the power system was completed. Most of these early period mechanical rice mills had wooden casings and belt conveyors that transmitted motor power.
External appearances of rice mills varied as to location and installation technician. However, the differences are negligible. Although a rice mill looks as if it is one unit, in actual, dehusking/dehulling and rice refining processes were separate operations. Therefore, a rice mill has two Material unloading opening and two Material discharge opening.
　

Asphalt coating helps  block moisture	Grains should not be in direct  contact with ground surface

　
◆《Storehouse storage before rice milling》
Generally speaking, farmers or operators preserve rice grains in dry form. This is because rough rice/paddy is less likely to become moldy. Once milled into brown rice or milled rice/polished rice, protection from hull is no longer available, which results to greater mold formation. Milling factory operators generally build storehouses to store rough rice/paddy. In order to avoid rough rice/paddy dampening, mold formation or germinating, anti-moisture handling is first done inside storehouses such as coating asphalt on walls to avoid moist from penetrating, and placing plywood on ground surface before placing rough rice/paddy so as to avoid direct contact with ground surface. [Ground surface has higher moist content] In addition, well ventilated storehouses also reduce humidity and heat which in turn ensure rough rice/paddy quality.

◆《First step of rice milling -dehusking/dehulling-remove hull to obtain brown rice》
As mentioned earlier, milled rice is subject to mold formation, thus, rice milling factories often estimate their delivery Qty to determine the amount of rice milling. During early periods, milled rice is mostly packed into large packages. Nowadays, people tend to eat less than before so rice usually comes in small packages.
Rough rice/paddy undergoing milling is first sieved to remove impurities such as sand, stones, cement, metal, and plastic using a destoner/stone picker. Then, it undergoes dehusking and dehulling. Rough rice/paddy is then dumped at Material feeder. Using an elevator, it is taken upwards through a precleaner where small pebbles and weeds are sieved. The hull sieved by a dehusker/dehuller then passes through several distributors and wind machines to separate brown rice and hull. Hull is blown by the wind machine to the chaff room at the back of the mainframe room for stacking. Brown rice then exits from the Material discharge opening. It is subsequently placed in a sack or plastic bag to weigh. During the grain ridging process, operators may observe the dehusking/dehulling progress in the distributors. If there is too much impurities in the brown rice, return to the distributor and wind machine through the switch valve to engage in separation once, twice, or three times until satisfaction is reached. If brown ice is desired, pack only after dehusking/dehulling. There is usually scales at the lower end of the Discharge opening for direct weighing. 　
　

rice stone separator	Internal bucket of elevator
Dehusker/dehuller	Distributor wire inside with holes  where brown rice and hull  are separated
Wind machine above the back of chaff room	Chaff blown and stacked in chaff room

◆《Second step of rice milling -rice refining-Bran layer and germinal layer are removed to attain milled rice/polished rice》
After rice dehusking/dehulling, it becomes brown rice which is ready to be cooked and served. However, though brown rice is more nutritious, it is less tasty. Most people are still accustomed to milled rice/polished rice. In order to change brown rice into milled rice/polished rice; “rice refining” is necessary. As said earlier, although the rice mill is one machine unit, dehusking/dehulling is separated from rice refining. Therefore, after brown rice is attained, it is refined by pouring brown rice into rice refining material unloading opening. Then, it is carried upwards to the bucket elevator for temporary storage. It subsequently enters a rice refining machine where fine bran is picked from brown rice. Meanwhile, milled rice/polished rice emerges. However, removed fine bran is still mixed in it so it has to be sent to the rice bran separator to remove most of the fine bran. Then, a fine bran wind machine is used to blow off minutes particles.
Most certainly, like dehusking/dehulling, rice refining is not completed in one single setting. Repeated refining is required to obtain milled rice/polished rice. At times rice milling factories add lime powder during the rice refining process to make rice appear whiter. Therefore, some rice mills have “lime powder adders” installed for easy lime powder adding.
Normally, rice refining has to be performed 6-7 times to completely remove fine bran. If rice appears white, the valve opens for rice to be released from the rice refining area exit. It is then ready for packing. There are scales at the lower end of the material unloading opening for direct rice weighing upon release.
　

Rice refining adjustment barrel  and rice refining machine	Fine bran remover
Lime powder adder〔Rice mill at  Science and Technology Museum〕	Scales are placed at the lower end  of the milled rice/polished rice  Material unloading opening for  operation purpose

◆《Conventional rice milling factories struggling for survival》
Setting up a rice milling factory requires capital funds, and lands. Therefore, rice milling factories were mostly established by wealthy people in the locality. Early rice milling factories not only outsourced rice milling, they also purchased rough rice/paddy from peasants and re-sold some of them to rice stores in the city after processing. They would leave a small portion of it to sell by themselves. One-line rice milling was developed as times changed. The state-of-the-art computerized equipments were more competent than conventional wooden rice mills. In addition, more and more farming houses purchased family type rice mills to perform milling themselves. This resulted to fewer outsourcing opportunities. Some small rice milling factories even stopped rice milling machine operation altogether and purchased packaged rice from large rice factories instead. They either became vendors or in some cases, were compelled to close down business. In a few years time, all these conventional rice milling factories are likely to disappear completely.