The main, specific environmental problem with polysilicon manufacture is the byproduct SiCl4 (silicon tetrachloride), which can be processed and recycled safely, albeit at very high temperatures, as is done in the West.* When simply dumped in the countryside, however, the liquid silicon tetrachloride releases highly-toxic and corrosive hydrochloric acid (HCl) and also generates a fine powder of silicon dioxide, the same material that sand is composed of, though the fine nature of the powder allows in to be readily inhaled or ingested. The production of HCl occurs when silicon tetrachloride reacts with water in the soil, eyes, mucous membranes, etc., and with moisture in the air.
Since villagers near the Luoyang Zhonggui plant had described blatant dumping by trucks from the plant, the Washington Post arranged for chemical analysis of dirt taken from the dump site. “The tests showed high concentrations of chlorine and hydrochloric acid, which can result from the breakdown of silicon tetrachloride and do not exist naturally in soil.”
Even though initial capital costs of silicon tetrachloride recycling facilities are high, and the operating costs are also high (because of the elevated temperatures required), it would be wrong to think that the money isn't available in China to implement this waste processing, it is simply a question of priorities. In fact, some Chinese are becoming extraordinarily wealthy from polysilicon companies, and Louyang Zhonggui, as reported by Ms. Cha, “is a key supplier to Suntech Power Holdings, a solar panel company whose founder Shi Zhengrong recently topped the list of the richest people in China.”
However, when faced with questions about environmental practices, the arrogance displayed by Luoyang Zhonggui company officials will unfortunately be all too familiar to those who follow civil rights or environmentalism in China. This attitude will be just as familiar to those who have followed the continuing struggle to introduce environmental controls to the United States over the past 50 years. As reported by Ms. Cha, “Wang Hailong, secretary of the board of directors for Luoyang Zhonggui, said it is "impossible" to think that the company would dump large amounts of waste into a residential area. "Some of the villagers did not tell the truth," he said.”
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