* September output up for copper, zinc; other metals down
* Copper at 680,235 T vs 664,954 T in August
* Aluminium at 2,715,557 T, lowest since May
By Polly Yam
HONG KONG, Oct 20 (Reuters) - China's refined copper production rose 2.3 percent in September from the previous month, hitting a three-month peak due to increasing output at some new smelters and higher supplies of raw material.
Refined copper production reached 680,235 tonnes in September, the highest since June and rising from 664,954 tonnes in August, data from the National Bureau of Statistics showed on Tuesday.
"Some new smelters have been gradually increasing production," said Ye Yugang, an analyst at Jinrui Futures. He added that some older smelters had also stepped up production after completing repairs in the summer.
That pushed up overall output slightly despite other smelters curbing production due to weak metal prices.
Jiangxi Copper has said it would cut output by 10 percent over the next few months. Jinchuan Group has crimped production due to problems in a sulphur facility.
Supplies of raw material copper concentrate also rose as imports jumped 5.2 percent in September, supporting metal production.
Copper output was likely to climb slightly in October, even though domestic demand was still lukewarm due to the slowing economy, Ye said.
Meanwhile, refined zinc production increased 1.1 percent to 536,745 tonnes in September, rising for the second straight month.
Demand for zinc is expected to improve in coming months because of Beijing's plans to increase investment in infrastructure projects, supporting prices ZN-1-CCNMM, industry sources said.
Production of primary aluminium fell 1.2 percent in September from the previous month to 2.72 million tonnes, the lowest since May this year.
Low prices have continued to prompt high-cost smelters to cut aluminium production, with Aluminum Corp of China (Chinalco) shutting its biggest facility. Still, the cuts were not big enough to push up domestic prices as new low-cost capacity came onstream.
Spot aluminium in China AL-A00-CCNMM has hovered around six-year lows since the third quarter, trading below 11,000 yuan per tonne on Tuesday, the lowest since late 2008.
Low prices and weak domestic demand also weighed on production of lead, nickel and tin.
Refined lead production dropped 1.6 percent from the month before to 313,620 tonnes in September, falling for the third straight month.
Refined nickel output stood at 28,376 tonnes in September, down 11 percent from the previous month and the lowest since March this year.
Refined tin production fell 3.6 percent to 14,380 tonnes in September, reversing a rise of 6.1 percent in August. (Reporting by Polly Yam; Editing by Joseph Radford)