Beijing Lianhua Yongxing science and Technology Development Co., Ltd.   

Beijing Lianhua Dadi Technology Development Co., Ltd. is a subsidiary of Lanzhou Lianhua Environmental Protection Technology Co., Ltd., established in Beijing. Lanzhou Lianhua Environmental Protection Technology Co., Ltd. (formerly Lanzhou refining and Environmental Protection Instrument Research Institute) is one of the earliest manufacturers of water quality monitoring instruments in China. In 1982, the company invented the first COD catalytic fast detector in China, which shortened the 2 hour reflux in traditional method to 10 minutes, greatly improved the efficiency and economic efficiency of the COD determination process. In 1984, this method, as the latest contribution of the world chemistry field, was included in the American CHEMICAL ABSTRACTS. After more than 20 years of unremitting efforts, the method has been widely used all over the country.