Introduction: Oil Sludge Origins

November 11th 2012, a company of petroleum was charged for its pollution in Nigeria for its oil pipeline leaked, and seriously polluted the environment of the three villages nearby in the Nigeria Delta region. April 2nd 2010, there was a leak of the oil sludge in Luochuan, Yan’an in China. The pond of the oil sludge collapsed and over 1000 tons of the oil sludge leaked. The polluted area included the farmlands, orchards, residence and river. The accident caused 400 homeless.

Three to five percent of all crude oil produced is ultimately unusable. When transported in ships or stored in tanks, sludge settles to the bottom of the vessels and containers. It cannot be drained from the tanks and must be removed and hauled away at considerable expense. Large volumes of sludge are also formed at refineries and oil extraction sites. Accidents in the transportation of oil and petroleum products also add to environmental contamination. The problem is common to all oil-producing countries.

Large volumes of sludge are formed during the transportation in ships or stored in tank, accounting for three to five percentage of all crude oil. Sludge settles to the bottom of the vessel and containers. It is possible to be drained from the tanks totally but has to be hauled away at considerable expense. Another source of sludge exists in refinery and oil extraction sites. Transportation accidents bring oil sludge to be environmental contamination, especially for those countries where there are oilfields.


I Principles and Regulations in France and in EU

A well judicial system for the management and prevention of oil sludge takes an efficient role in France and European areas, which ensures its recycling and treatment.

In France, sludge after treatment is regarded as fertilizer in agriculture. The fertilizer should take well pre-analysis and study to enhance its serious traceability. The sludge producer is responsible for it until the end of elimination to ensure the safety.

The treatment of sludge helps to reduce the fermentability and the potential healthy risk for its usage. The cut-off grade is divided into two degrees according to previous regulation. The usage of the fertilizer from sludge is limited only when it is proved to be beneficial for mud and agriculture. The fertilizer is prohibited to be used under certain conditions like freezing, snow and steeply sloping ground.

The producer of the sludge should finish a study for the land sustainability, well describing the concept and the procedure of sludge treatment. An alternative solution for the treatment should be prepared in case of unexpected potential obstacles. The temporary storage of oil sludge field is only for solid and stable sludge during the application period.

Monitoring process should be well conducted by the producers in order to assure the traceability of the oil sludge. An annual report with the record of sludge characteristics should be achieved. The Prefect of the locale supervise the monitoring procedure.

Independent organizations of the sludge producer are responsible for applications. Since 1998, there is a national committee, cooperating closely with related partners, to monitor and evaluate the sludge which win the confidence of all.

Directive 86/278/EEC on the protection of the environment and in particular of the soil, the use of sewage sludge in agriculture defined at Community level the minimum quality standards for sludge and receivers, and establishes the principles of traceability for the valuation of these materials soils. This directive was published in 12 June 1986 at the EU Council.

In France, the sludge from the treatment of domestic wastewater is considered as waste in the sense of the regulation. The application of these materials on agricultural or forest plots is subject to a strict regulatory framework. Articles R. 211-25 to R. 211-47 of the Environmental Code and the Decree of 8 January 1998 made under the Water Act of 3 January 1992 have clarified the French regulation of spreading of sludge from the treatment of urban wastewater. These texts lay down the conditions of application to provide the necessary guarantees of their safety.

The compost of the sludge is considered as the production. It should coherent to standard NF U 44-095, which is defined as mandatory application by the Decree on 18 march 2004. The Directorate-General for Competition, Consumer Affairs and Prevention of Fraud controls and implements the regulation for the compost.


II Principles and Regulation in China

In the announce No.18 2012 of the Ministry of Environmental Protection of the People’s Republic of China, it is mentioned that the government has the determination to deal with the oil sludge. Policies are published to encourage eco-technology progress.

By the end of 2015, the new or advanced projects should use the clean process technique and technologies. The recycle rate of the industrial sewage must be over 90% and the harmless treatment of the solid waste must be 100%. It encourages the society to develop and extend the new technologies in the following three sections:
1.Environmentally friendly oilfield chemicals, acidizing fluid, fracturing fluid, drilling fluid, alternative technologies for acidizing and fracturing, drilling waste processing technology to improve the gas purification plant sulfur recovery technology
2. Carbon dioxide EOR technology, low-permeability formations injection water treatment technology
3. Waste drilling, underground work, the recycling and harmless treatment of the oil sludge, rapid degradation of petroleum contaminants technology and the restoration of contaminated soil or groundwater

Among “Standard for Pollution Control on the Security Landfill Site for Hazardous Wastes” （GB18598—2001）and “Pollution Control Standard for Hazardous Wastes Incineration” （GB18484—2001）in China, oil sludge is defined to be hazard solid waste. The standards of oil sludge treatment are mainly decided by its production, including the indicators of heavy metal and the percentage of oil content. They vary from the usage of road construction to that of agriculture.

China Environmental Law precise the monitoring and supervising responsibility of the government department, and a corresponding mechanism should be set up for enterprises to report the information of waste releasing and the risk for environment and health. Comprehensive inventories of key polluting units are obliged to disclosure.

The principle of oil sludge treatment is to reduce the source and control the process of production. The treatment target is to minimize, to stabilize and to decontaminate. Local government department takes the main responsibility to plan and construct the sludge treatment and disposal facilities. The operation unit of the sludge treatment is responsible for safe disposal. Local government department has the priority to purchase the derivatives of sludge treatment.

The operation unit should record the information of treatment and transport. The documentary should be reported to local government department regularly. A management mechanism should be set up within the operation unit to note the detection, recording, archive and reporting, as well as the usage of the treated sludge and its derivatives. The entire documentary should be preserved at least for five years.

Units where make use of the sludge productions should entrust a third party with relevant qualifications to evaluate the environment condition changes after the exploiting. The exploited sites are prohibited from farming domestic animals and poultry.

Apart from the “Environmental Protection Law of the People's Republic of China” and “Law of Solid Waste Pollution Prevention and Control of the People's Republic of China”, special technical standards are supplementary for oil sludge treatment. The General Standards for Pollution Control of Industrial Solid Waste Storage and Disposal Site（GB 18599-2001）, the Standards for Pollution Control of Hazardous Waste Storage（GB 18597-2001）and the Standards for Pollution Control of Hazardous Waste Landfill（GB 18598-2001）were implemented on 2001. They were revised and published on 6 August 2013 by the Ministry of Environmental Protection and the State Administration of Quality Supervision, Inspection and Quarantine of PRC jointly.