Odiete William E, Agunwamba Jonah C
Department of Civil Engineering, University of Nigeria, University Road, Nsukka, Enugu State, Nigeria.
Heliyon. 2019 May 18;5(5):e01620. doi: 10.1016/j.heliyon.2019.e01620. eCollection 2019 May.
The regulatory effluent oil limit which is the allowable quantity of hydrocarbons in industrial and stormwater effluents varies from one country to another. Several authors have suggested the need to improve the design methods of conventional oil-water separators because current design methods do not address the quality of effluents produced despite the fact that the conventional oil-water separator is the predominant wastewater treatment facility in developing countries. Regulatory effluent oil limit and oil separation efficiency are not design parameters of the current standard design methods for conventional oil-water separators but there is pressure from environmental regulatory agencies on companies over compliance with regulatory effluent oil limit for industrial wastewaters. This research work conducted a survey on the oil content of the wastewater effluents of some functional conventional oil-water separators in the Niger Delta, Nigeria. Sequel to the outcome of the survey, this work invented novel design methods for conventional oil-water separators titled: novel design approach, innovative design approach and alternative design approach through mathematical modeling. The novel design methods apply the concept of design volume, novel sizing data and novel mathematical models to design conventional oil-water separators that conform to American Petroleum Institute (API) design criteria for conventional oil-water separators; taking into account oil separation efficiency and the regulatory effluent oil limit of a country to establish the technical basis for the periodic evaluation of separator performance and evaluation of compliance with the environmental regulation. The conventional oil-water separators designed with the novel design methods conformed to API design criteria and their dimensions are similar to dimensions of separators designed with the City of Tacoma design approach (a certified design approach), thus validating the novel design methods for the design of conventional oil-water separators. The novel design methods have global applicability. They can be applied in every country.
监管排放油限值是指工业废水和雨水排放中允许的碳氢化合物量,不同国家各不相同。一些作者提出需要改进传统油水分离器的设计方法,因为尽管传统油水分离器是发展中国家主要的废水处理设施,但目前的设计方法并未考虑所产生废水的质量。监管排放油限值和油分离效率并非传统油水分离器现行标准设计方法的设计参数,但环境监管机构向企业施压,要求其遵守工业废水的监管排放油限值。本研究工作对尼日利亚尼日尔三角洲一些正常运行的传统油水分离器的废水含油量进行了调查。基于调查结果,本研究通过数学建模发明了传统油水分离器的新颖设计方法,即新颖设计方法、创新设计方法和替代设计方法。这些新颖设计方法应用设计容积概念、新颖的尺寸数据和新颖的数学模型来设计符合美国石油学会(API)传统油水分离器设计标准的传统油水分离器;同时考虑油分离效率和一个国家的监管排放油限值,为定期评估分离器性能以及评估是否符合环境法规奠定技术基础。采用新颖设计方法设计的传统油水分离器符合API设计标准,其尺寸与采用塔科马市设计方法(一种经认证的设计方法)设计的分离器尺寸相似,从而验证了传统油水分离器新颖设计方法的有效性。这些新颖设计方法具有全球适用性,可应用于每个国家。