Environmental protection is about more than just technology, said Zhang Jian, founder and general manager of EnviroSystem Engineering & Technology Co Ltd.

It requires mankind to innovate completely new development models, he said.

"The world used to copy the urbanization model of Europe, but now China can not afford to copy it because it was not eco-friendly," he said.

The Zhongguancun-based company, which has nearly 60 patented technologies, specializes in innovative drainage system solutions.

"Our job is to pursue an eco-friendly lifestyle using modern technologies," he said.

The water treatment plants in Beijing handle 3,000 tons of sludge every day, around 1,000 of which can be turned into resources. Around 90 percent of the technologies used in this process are developed by EnviroSystem, Zhang said.

One of its innovations is a technology that sorts different kinds of waste at the point of entry into the sewage system. It draws out useful human waste, which accounts for only 1 percent in the sewage but contains many resources, such as nitrogen, phosphorus and potassium.

After disinfection, the material is returned to the land as fertilizer. And other parts of the drain water can be recycled.

The system will be highlighted in the China Beijing International High-Tech Expo.

In the current model, all waste of an entire city or township is delivered to a collective treatment facility through a sewage network, the infrastructure of which is costly to maintain, Zhang explained.

The new system requires great changes in the current one so the company's focus is on new communities, especially those in the countryside that are being created by the process of urbanization.

The system is already in use in cities throughout the country, proving that the concept is "economical and practical", Zhang said.

In Handan city, Hebei province, there is a mid-sized village with around 1,000 residents that has introduced the recycling system, which has reduced water use by 80 percent and the total cost is half of that of the traditional urban water treatment model, according to a research team from the Chinese Academy of Sciences.

"It is easy to reduce emissions but difficult to preserve energy," Zhang said.

"In the past, we reduced emissions in the cost of increasing energy consumption, but now we will rethink this matter from the very beginning."

zhangzhao@chinadaily.com.cn

(China Daily 05/24/2013 page5)