Reuters: Struggling from weak demand and facing new rules to clean up pollution, some firms in China's top steel producing city have scaled back production or even closed completely, lifting local steel prices off 20-year lows. China is using tougher environmental rules to help tackle a severe steel capacity glut that has depressed prices and saddled much of the sector - the world's biggest - with crippling debt. Tangshan, which is 200 km (124 miles) east of Beijing and produces more steel a year than the...