“引洮工程”引发的受水区污染治理研究

[目的]为了解决甘肃中部安定区、陇西县、渭源县、临洮县、榆中县和会宁县的人畜饮水、工业用水、生态用水及农业灌溉用水问题,引洮工程通过九甸峡水利枢纽抬高水位将黄河上游洮河支流水资源引入受水区。在受水区,在调水增加本区供水总量的同时,相应增加了增量水资源使用后带来的废污水,客观上对污染治理工作水平提出了更高要求,轻视排污问题将加剧受水区乃至下游的水系污染程度,影响受水区经济社会的可持续发展。[方法]文章采用文献研究法从理论上探讨了环境容量、排污权及其关系。采用定额计量法计算了调水带来的COD和氨氮增量。[结果]调水使得受水区COD和氨氮每年分别增加6 914. 30t和1 440. 48t。就COD而言,受水区平均排放量占该区环境容量的51. 12%,似有较多的容量结余,但区内排放极不平衡,榆中和会宁已经超排。就氨氮而言,受水区平均排放量将占该区环境容量的151. 55%,总体超排很严重。区内除临洮以外,其余5县区均超排,其中,榆中和会宁超排1倍以上。[结论]排污量是假定增量污水符合二级排放标准的前提下计算的,如果处理率低、排放达标率低,则超排现象会更为严重。对此,要从宏观上进行综合治理,诸如完善政府、社会与市场共同治污机制、排污权配置的过渡性制度安排、污水处理企业改革及引导受水区进行产业结构调整等。

STUDY ON POLLUTANT GOVERNANCE TRIGGERED BY THE TAO RIVER WATER DIVERSION PROJECT

Tao River Water Diversion Project will raise the water level upstream of Tao River of the Yellow River branch through Jiudian Reservoir and transfer water resources into the receiving water area in order to solve the problems of drinking water, industrial water, ecological water and agricultural irrigation water of Anding, Longxi, Weiyuan, Lintao, Yuzhong and Huining which locate in the arid area of central Gansu province. In the receiving water area, the total amount of water supply is increased while the waste water is increased accordingly. The increased pollutants give us higher requirements for pollution control work objectively. The pollution degree of the receiving water area and the downstream water system will be aggravated. If we despise the pollution problem, which will affect the sustainable development of the eco society in the recipients. Using the method of literature, the environmental capacity, the pollutant discharge right and their relationships were discussed. Increment of COD and ammonia nitrogen of the water transfer was calculated by the quota method. The results showed that COD and ammonia nitrogen in water receiving area rise annually by 6914.30t and 1440.48t, respectively. The average emission accounts for 51.12% of COD of the environmental capacity of the region, and there seemed to be more capacity surplus.However, the emission was extremely uneven,Yuzhong and Huininghad exceeded. The average emissions account for 151.55% of ammonia nitrogen of the total environmental capacity of this area. The 5 counties exceeded except Lintao. Yuzhong and Huining exceeded more than 1 times. We calculated pollutants assuming 2 level emission standard. If the treatment rate and the emission standard rate were low, the problem was serious especially. Comprehensive measures should be taken from the macro perspective, such as adopting governance mechanism of government, society and market, establishing of transitional institutional arrangement for emission rights allocation, reforming sewage enterprises, and guiding the recipients to adjust the industrial structure. etc.