At present, domestic urban sewage treatment plants, whether existing or new, are generally smaller than the GB18918-2002 standard. One important reason for this is that the essential characteristics of technology, design level, and business level, as well as the comprehensive technical level of maleic acid acrylic acid copolymer, cannot meet the requirements. The GB18918-2002 standard is a mandatory standard, which includes feasibility assessment, environmental impact assessment approval, environmental acceptance, daily supervision and management work efficiency audit process, and debates that are often left unresolved, resulting in a significant waste of management resources.

In addition, the convergence of local and national standards is a very important aspect. The Beijing Municipal Water Pollutant Discharge Standard (DB11/307-2005) stipulates that the effluent quality of sodium polyacrylate sewage treatment plants in cities is Class III, IV, and V. The comprehensive discharge of sewage in Shanghai follows the GB18918-2002 Class 1B standard; the GB18918-2002 standard (draft for soliciting opinions) is still the implementation of the discharge standard for urban sewage treatment plants. The Guangdong Provincial Local Water Pollutant Discharge Standard requires a Class I COD standard for the effluent of urban secondary sewage treatment plants, which is 40 mg/L, relaxed when ammonia nitrogen is 10mg/L, and phosphate is 0.5 mg/L. However, the current technological level is difficult to meet these discharge standards.

China's economy and construction have experienced rapid development over a period of time, with cities or regions of various industrial scales and industrial structures changing their urban construction layout in a timely manner. Coupled with water conservation and adjustments to water and other factors, sewage flows into treatment plants, and the types and concentrations of pollutants seriously deviate from the design conditions followed. The impact of these changes on emission standards cannot be ignored. The rapid development of the Chinese economy should last for a considerable period of time, with a standard revision cycle of 5 years. The urban sewage treatment industry is undergoing rapid development and industrial upgrading, and this cycle may be shortened.