Waste disposal in the Chinese cement industry: part one

Introduction

At the end of 2014, China’s installed capacity reached 3 billion t of cement produced by the new dry process. The total capacity of mainland China therefore equates to about 65% of worldwide cement capacity. Following significant growth over the last 30 years, China’s cement industry has fallen into overcapacity. Associated problems such as frequent plant stops, price wars, the investments needed to conform to new environmental regulations and weakened demand have all caused headaches for the CEOs of Chinese cement companies. However, the Chinese central government is focused on developing technology to achieve the goal of being environmentally friendly and low-carbon, part of which is encouraging the Chinese cement industry to treat municipal waste in China. The Ministry of Industry and Information Technology of the People’s Republic of China (MIIT) announced several stimulation policies and regulations so that Chinese cement industry could make a greater contribution to a low carbon economy, including the use of municipal garbage and sewage sludge in the cement pyroprocess.

Current status

During the 11th 5-year term, the Chinese government has spent a lot of money to minimise the negative effect to humans of odour from municipal garbage, to minimise air pollution, and to develop planting areas. However, the current situation is still far from meeting government expectations. The following is a summary of municipal and industrial waste treatment:

Municipal waste

Due to Chinese lifestyle and eating habits, it is estimated that 0.3 kg/day of waste is produced per person with moisture of about 30 ~ 50% and even higher during summer time. The traditional means of treatment by incineration for power generation, sanitary landfill, composting and fertilising cannot cope with the increased quantity of municipal waste. The major means of disposal way is still by landfill, which requires a huge amount of land. 75% of waste is landfilled in the city and more than 85% in the country. While waste is waiting to be treated, it becomes a threat to those living nearby.

Industry waste

There are billions of tons of coal gangue, slag and other industry waste stocked outdoors, which not only occupies land but also pollutes the air with dust, odour, acid-based rain, etc. To add to that, there is still more industry waste produced every year. Even if the government issued a lot of stimulation regulation, whether by tax rebate or a policy to compensate the use of these materials, the impact on the environment and the pressure from waste disposal would still be high.

In 2012, there was about 3 billion t of industry waste from China. Among these are about 1.2 billion t coming from the mining industry, about 400 million t of coal gangue from mining coal, about 500 million t of ash and about 400 million t from the metallurgy industry. The total re-used industry waste is about 2 billion t in 2012 by hollow blocks, new building materials, road construction, additives in cement or concrete and so on, but the total increased industry waste is still about 1 billion t.

This is part one of a three-part article written by Shixiang Chen for World Cement’s October issue and abridged for the website. Subscribers can read the full issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the October 2015 issue here.

Read the article online at: https://www.worldcement.com/asia-pacific-rim/28092015/waste-disposal-chinese-cement-industry-673/