The Environment Crisis Generated by Oil Drilling Waste and Its Management

Sep 20, 2013

On March 26th, “The Guardian” put a global spotlight upon a coverage, saying that Peru which is located in Amazon forests made a sudden declaration of the environmental state of emergency in a part of its northern Amazon forest. This was due to the oil drillings operated by Argentinian Company Pluspetrol that had created highly unacceptable levels of lead, cadmium, chrome and petroleum-related compounds contamination in soil.

This declaration was made because the checks carried out by Peru’s Environment Ministry this February and March has found overly high levels of lead, cadmium, chrome and petroleum-related compounds in the soil at different points in Pastaza valley. The drilling waste produced in the process of oil drilling can be drilling sewage, drilling fluids, drilling cuttings and dirty oil compounds. It is a kind of stable colloidal suspension, consisted of clay, weighting materials, chemical agents, sewerage, dirty oil, cuttings, etc. as well as some other harmful chemical elements like, hydrocarbon, salt, polymers, heavy-metal ions, some particles in barite, asphalt and other modifiers. All the elements concerned have been the major contaminants in oil exploration since they own such properties as high chroma, high oil content, high COD, high suspension, high salinity and so on. Every finished well in oilfield may produce a waste slurry pond. However, one oilfield is comprised by tens of thousands well which may produce tens of thousand slurry ponds, including at least hundreds of cubic meters or at most thousands of cubic meters drilling waste. Since the waste contains soluble inorganic salt contaminants, heavy metal contaminants and organic hydrocarbon contaminants, that would be an ideal solution to simply pile it up or bury it in some pits. Rain immersion and river brush could easily make it harmful to its surrounding soil, water sources, farmlands and air.
 

Hi-G Dryer
 

Achuar and Kichwa indigenous people have always been living in Pastaza River basin bordered between Peru and Ecuador. They have complained about the pollution all these decades which the successive governments failed to deal with. Officials indicate that for years the state lacked the required environmental quality standards.

Peru issued a new law on March 25th in order to complete the standards, which for the first time set out the acceptable limits of soil contaminants and has been considered a key advance. Accordingly, Peru’s Environment Ministry gave Pluspetrol 90 days to clean up the affected areas and reduce the risk of pollution to the local residents.

As the largest oil & natural gas producer, Pluspetrol took over from Occidental Petroleum and operated Peru Oilfield in 2001, but neither party has cleaned up the pollution. Several multi-million dollar fines have been levied against Pluspetrol in recent years, including the 1.1 million dollars ( 6,832,000 CNY ) fined for failing to clean up the oil spill in the Peru’s largest national park. Peru’s Environment Ministry says that they will further the environmental checks in other Pluspetrol oilfields.

To protect the environment will benefit both the contemporary and the future generations. Nowadays, many countries have passed legislations based on their own scenarios for the ever-worse global environment, hopefully resorting to laws would bring about good environmental behaviors. And meanwhile, oil exploration as a high-pollution industry must also seek a new production pattern to balance environmental protection and benefits.

Accordingly, KOSUN launched a relative solution by the integration of domestic and foreign drilling waste management experience and methods as well as the consideration of drilling waste production process. It would reduce at the source, i.e. purify the drilling fluids and take away the solids at the source by application of solids control system. Then dewatering of discharged waste, water treatment, water recycling and purifications would work altogether to minimize water content in waste and recycle the water. Afterwards, Hi-G dryer and vertical centrifuge would continue with dewatering and mud/gas separator to minimize waste disposal. At last, the discharged waste would be reasonably and effectively treated by means of solidification, biodegradation, thermal desorption and cuttings re-injection.