Research and assessment of sludge management in Thu Dau Mot wastewater treatment enterprise. The composition of the sludge depends on the composition of the wastewater, the wastewater treatment process and the sludge treatment process. The most common non-toxic organic compounds include materials of plant and animal origin such as proteins, amino acids, sugars, fats ... compounds containing N, P... Toxic organic compounds include compounds of PHA (Poly-nuclear aromatic hydrocarbons), alkyl phenols, polychlorinated biphenyls (PSBs) organochlorine pesticides, phenols, chloro-benzenes ... Heavy metals such as: Zn, Pb, Cu, Cd, Ni, Cr, Hg, As… (in the range from 1ppm to 100ppm). Some of these compounds can be toxic to humans and animals. Therefore, it is necessary to control the concentration of heavy metals in the sludge before disposal or reuse. Harmful microorganisms such as pathogenic bacteria, viruses and protozoa together with parasitic helminths can increase the potential harm to human, animal and plant health. Inorganic compounds such as silicates, aluminates, calcium and magnesium compounds.

Bien Hoa City is an urban area of Dong Nai province located in the Southern key economic region. Currently, Bien Hoa City has 6 industrial parks in operation with large daily wastewater flow, causing environmental risks, especially from organic pollutants. The study applied the Nemerow risk index and the geographic information systems (GIS). The results showed that the industrial parks were mainly organic pollution levels including N-total, P-total, and Ammonium. The level of environmental risk from organic pollution was recorded in range of medium to very high levels, the ranked in descending order: Agtex Long Binh Industrial Park (P = 24)> Amata Industrial Park (P = 16)> Bien Hoa 2 Industrial Park ( P = 10),> Tam Phuoc Industrial Park (P = 5)> Loteco Industrial Park (P = 3). The results of the study provided good information for the management and improvement of wastewater quality in the industrial wastewater treatment plants of the industrial parks in Bien Hoa City.

Nowadays, the benefits of ISO 14001:2015 abound, for minimizing environmental footprints, providing operational improvements, bringing lucrative business and improving the company’s image. There is an annual audit to decide if the company’s environmental management system meets the requirements of ISO 14001:2015. This is a significant audit that strongly affects the current certificate. The study to “Evaluate the efficiency of the environmental management system ISO 14001:2015 at the Vietnam Onamba Company” has been conducted to research the internal audit and examine any discordance in the environmental management system. The study carries out the internal audit of the environmental management system ISO 14001:2015 at VTO company by 3P method (P1: Paper check, P2: People interview, P3: Practice Observe). The result of the study showed a minor discordance at (6.2) Environmental Objectives and planning to achieve them. Regarding other clauses, they meet the requirements of the environmental management system. The result shows that the responsibility and careful observation of the company in controlling the system. The study evaluates reducing consumption (electricity, water, and chemicals) through collecting and comparing the data between 2017 and 2018. The results show the efficiency of reducing consumption: monthly electricity consumption reduced 21,86% (377 MWh); monthly water usage reduced 17,89% (1421 m3 ); annual chemical usage reduced from 3 to 6%.