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The History of Mud Testing

Jan 18, 2011
Marie Brannon

Before Baroid offered commercial mud testing services to the petroleum industry, mud men experimented with various techniques to test drilling fluids

Drilling mud was first tested for commercial purposes by the Baroid Division of the National Lead Company in 1929 in Houston, Texas. They also produced the first commercial mud testing products. Before 1929 drillers dug clay out of any nearby bank or used native earth.

From Mud Buckets to Precise Instrumentation

Between the discovery of Spindletop in 1901 and the appearance of Baroid in 1928, there were nearly three decades of rotary drilling. The old-timers tested their mud by “rule of thumb”. They knew two kinds of mud: thick and thin. New workers learned from the veterans how to pick up a handful and determine just the right thickness needed.

By 1913, drillers were aware of gelation. Since the well was often shut down for lunch break or other delays, the mud would gel during the break, and the workers called this “getting logy”. They discovered that if they started the pumps occasionally during shutdowns, it would keep the circulation free.

They also could tell if the mud was gas-cut by observing the froth or foam in the mud pit. During the winter of 1913, the Bureau of Mines conducted the first engineering studies by sending J.A. Pollard and A.G. Heggem to Oklahoma oil fields to test the properties of drilling mud. The resulting report was published in 1916 and holds the distinction of being the first ever technical bulletin on the subject.

In early field tests, samples of clay were mixed by hand in an ordinary wash basin. Circulation tests were made by adding two quarts of red paint into the drill pipe at the surface and timing the period required for the color to appear in the mud pit. One record of such a test provided a time of two hours and 33 minutes for circulation in a hole that was slightly more than 3,300 feet deep.

Heavy Drilling Muds

Early on, researchers discovered that all “thick” muds did not weigh the same. It was believed that heavier muds could be useful in drilling against gas pressures, so the California Department of Petroleum and Gas conducted some tests with five-quart containers.

These were calibrated so that one gallon fluid would fill exactly 4/5 of the inside and was marked with a ridge. They also had scales that would accurately record weights up to 30 pounds showing a difference in just one ounce. This was the prototype for the first piece of mud-testing equipment ever produced, by Baroid in 1929.

Between 1917 and 1922, when college degrees were first awarded in the field of Petroleum Engineering, mud testing began to receive serious attention from both scholars and manufacturers. The specific gravity (weight) of drilling mud was tested using oilfield hydrometers that were adapted for this use.

Several different terms and scales were used to express results, including pounds per cubic foot or pounds per gallon. They also developed a specific gravity scale. In 1921, petroleum geologist Dorsey Hager said “Mud-laden fluid has a specific gravity of from 1.15 to 1.3, and weighs from 72 to 81 pounds, as against 62.5 pounds per cubic foot of water. It exerts a pressure of 0.499 to 0.564 pounds per square inch, as against 0.434 for pure water”.

Gradually, oil men realized that not only weight but viscosity should be considered. Standard Oil Company of California engineers used a McMichael viscometer to test mud. It measured the friction of a liquid against a disc suspended from a calibrated wire, in a cup of liquid which was rotating at a constant speed. The ancestor of the Marsh funnel was the Engler viscometer, originally developed by Dr. Charles Engler in Germany in 1884 for use in the railroad industry.

Testing the Viscosity of Drilling Mud

Various rotary viscometers were also in use to test the viscosity of oil. The Napier and Cockrell types were early predecessors of the Stormer, Fann and Baroid devices. Napier and Cockrell apparatus was in use for more than fifty years and utilized paddle wheels revolving in oil or other fluids. There is no record that these were used to test mud, but they were described in oil engineering texts of the time and may have been used in this manner.

In 1930, Baroid introduced the first mud bucket and scale as a test instrument. These were given away as free samples, but by 1934 they began to equip vehicles for field testing. These cars carried a Marsh funnel, a Stormer viscometer, a portable mixer, an electric hot plate, screens, graduates, a Mudwate Hydrometer, a Wulff pH tester, a balance, and a mortar and pestle. Around 1936 they added a mud balance that had been developed by Phil Jones of the Union Oil Company of California.

References:

“The History of Mud Testing”, Baroid News Bulletin October 1960

Shale Shakers and Drilling Fluid Systems, by American Association of Drilling Engineers, Gulf Publishing Company, 1999

Oil Field Practice, by Dorsey Hager, McGraw-Hill, 1921

Read more at Suite101: The History of Mud Testing

Barite Market Tight as China Supplies Decrease

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by  Jaime Kammerzell | Rigzone Contributor

Tuesday, December 20, 2011

There is a growing shortage of barite supply, which has the oil and gas drilling industry looking for alternatives. Barite, the mineralogical name for barium sulfate, is used primarily in oil and gas drilling, but also is used as non-toxic filler, extender or weighting agent in plastics, paints and rubber, and as a shield around nuclear power plants. It also has medical uses such as blocking x-ray and gamma-ray emissions, and a pharmaceutical grade barite is used for barium milkshakes for intestinal x-rays.

To understand the barite market today, Brian O’Connell, Senior Category Manager of Mined Products, Baroid Supply Chain Group of Halliburton, explained that “the cost of barite over the past 10 years has quadrupled, in the last 5 years it has tripled, and over the past 2 years it has doubled.”

In addition to the cost increase, a decrease in quality related to metals and contaminants and a decrease in availability of 4.2 g/cu cm, which has historically been the API specification, are contributing to the current supply issues.

Global Barite Production

Most barite comes from China, which was responsible for 51 percent of the global supply in 2010. India had a 14 percent share of the barite market followed by the U.S. with 9 percent, Morocco with 7 percent and the rest of the world with 19 percent, according to the Barytes Association. Mined barite in 2010 totaled 7 million tons.

“China is the major barite source and leads the market,” O’Connell said.

2010 Barite Production By Country

China’s mining industry is undergoing a safety overhaul as many accidents and deaths in non-oil and gas related mining industries have prompted the government to enforce stricter regulations comparable to U.S. regulations. With these new regulations comes additional expense that smaller mines can’t meet. Thus, the supply burden has fallen on the larger mines.

However, in some cases, the local and regional Chinese authorities have reduced production from the larger mines.

“Up until about 2 1/2 years ago in Xiangzhou County, otherwise known as Elephant County, in Guangxi province, the Chinese were producing 1.2 million tons of barite per year. This year, the volume has fallen to 300,000-350,000 tons, which is a reduction of almost 1 million tons out of China,” O’Connell explained. “With global barite production of 7 million tons in 2010, a 1 million ton reduction is a big hit to the market.”

To add to the cost, as miners produce more and more barite, they have to dig deeper and further away from export ports. Recent weather-related problems like flooding, droughts and earthquakes not only impacted barite mining, but also transportation to these export ports.

O’Connell also points to the U.S. dollar/Chinese Yuan exchange rate, which has seen a 25 percent change since 2005, as a source of rising barite costs.

According to O’Connell, the high level of worldwide drilling activity correlates to an increase in barite demand. Peak demand and a reduction of barite coming out of China are driving the price and quality issue. “With this kind of imbalance, the scale tips in favor of sellers,” O’Connell said.

India’s barite market also is impacting the global barite market. India is the second largest producer of barite in the world. However, the country only has one major source of barite and the government owns it. The government entity that manages the mine, APMDC, holds two tenders every three years. The first tender calls for bids to mine the barite, and the lowest qualified bid wins the business. The second tender calls for bids for the barite that comes out of the mine. This goes to the highest qualified bidder.

The latest tender in 3Q 2011 resulted in a dramatic overnight price increase of more than 70 percent on a freight on board (FOB) Chennai basis.

U.S. Barite

The United States produced about 9 percent of the world production in 2010 of barite and imports much of its demand. As major world-wide buyers, Baroid and other fluid service companies typically ship in large lot sizes — 60,000 tons in one shipment — from China to the U.S. Gulf Coast. But Chinese traders are having increasing difficulties accumulating that much material at one time, O’Connell explained, and as a result, lower quality material is making its way into cargoes to fill out vessels, resulting in inconsistent material quality.

Back in 2006, a major barite producer with Nevada mining operations converted to a lower grade of barite, 4.1, to extend their U.S. reserve base and reduce their reliance on imports. According to O’Connell, Baroid immediately followed, and the other two barite producers in Nevada followed soon after.

The Baroid mine in Dunphy, NV
The Baroid mine in Dunphy, NV

The 4.2 and 4.1 barite grades from U.S. sources have basically the same types of impurities. All four of the Nevada producers sold the lower grade product prior to API approval with general customer acceptance. At the same time that this grade was being used in the field, the four major fluid service companies encouraged API to add the lower grade to the approved products list, which has been done.

“We are trying to get operators to stop using material that has a higher density than what they really need. As an industry, we’ve been pretty successful,” O’Connell explained.

O’Connell indicated that the trend toward 4.1 barite is spreading globally and is helping to reduce pressure on miners to dig deeper for of 4.2 barite.

Regardless, the current supply is so tight, fluid service companies are considering alternative materials or even lighter weight barite than 4.1.

“We’ve looked at hematite and calcium carbonate, but each has characteristics not suitable for weighting of mud like barite, which is why we are looking into lighter barite instead of alternatives,” O’Connell said.

Source – RIGZONE

Bulk tanks, thermal systems advance environmental efficiency of cuttings handling

By Katie Mazerov, contributing editor

In response to heightened industry and regulatory standards, service companies are continuing to introduce innovative technologies to improve the safety and environmental responsibility of solids control and cuttings handling.

Part of Baroid’s FullCircle® cuttings reinjection process, the two-stage hammermill grinds waste and cuttings to a slurry before they are injected into the formation for disposal. FullCircle The cuttings injection service helps eliminate costs and risks of cuttings handling and disposal.

“Solids control and waste management technologies assist the operator in achieving regulatory standards and provide effective mud conditioning for drilling operations,” said Ana Djuric, global environmental advisor for Halliburton’s Baroid business line. “Solids control is regulated for health, safety and environmental (HSE) standards, but the efficiency and throughput of solids control equipment are not directly regulated,” Ms Djuric said. “Indirectly speaking, disposal limits in a given area are what drive solids control efficiency.”

The primary purpose of solids control is drilling fluid conditioning, or removing as much of the unwanted solids as possible from the drilling fluid, she explained. “But the secondary purpose is to achieve regulatory disposal limits through effective waste management such as cuttings dryers and cuttings treatment equipment,” she said. Equipment selection is determined by several variables, including hole volume, available space on the rig and subsequent discharge in the area.

Halliburton’s Honey Comb Base (HCB™) tanks are used for bulk transfer of waste. In an offshore operation, waste is conveyed pneumatically by the SupaVac™ SV400 cuttings collection and pumping system through hoses from the HCB tanks on a rig to tanks or collection pits on a boat to be transferred onshore.

“Solids control equipment assists in environmental compliance by helping the operator remove unwanted solids, rock cuttings and particulate materials from the drilling fluid during operations,” Ms Djuric continued. The wastes can then be treated with secondary recovery or treatment equipment to extract additional fluids from the solids for reuse in drilling operations.

Among the latest advances are Halliburton’s Honey Comb Base (HCB) tanks, which improve the efficiency of handling cuttings for disposal. “By storing cuttings in pneumatic bulk tanks, as opposed to traditional skips, crane lifts are virtually eliminated in regards to cuttings handling,” explained Greg Abbott, manager, Solids Control Systems for Halliburton. “At the same time, bulk tank storage significantly reduces the chances of spilling oil-contaminated drill cuttings while transporting them from the drilling locations to disposal locations.”

Better thermal systems and methods of bulk handling also have been developed. “In many ways, it’s the chemistry that is the environmental driver rather than the mechanical processes associated with solids control and waste management,” Ms Djuric noted.

Achieving optimal environmental standards is complicated by the myriad regulations that vary by country, state or province and even county. Offshore regulations are more standardized than onshore, but agencies such as STRONGER in the United States are working to provide a more harmonized approach to drilling waste regulations and practices. “In offshore regions where regulations are lacking, North Sea or Gulf of Mexico standards commonly apply,” Ms Djuric said. Offshore, the primary environmental concern is to protect aquatic species from the generally monitored parameters of hydrocarbons, chemical toxicity, degradation and, in some areas, bioaccumulation.

“On land, Louisiana 29B or Alberta’s Directive 50 are commonly used as a reference point. But harmonization is very difficult to achieve on land due to the wide diversity of ecosystems,” Ms Djuric explained. Depending on the location, onshore environmental compliance can range from protection of vegetation, agriculture and soil quality, to safeguarding water quality and associated aquatic species, or drinking water conservation. Metals, salts, including chlorides, hydrocarbons and chemical toxicity are the parameters typically monitored.

Thermo–mechanical cuttings cleaner is used to process oil-contaminated drilling waste. Oil and water are separated from the cuttings by mechanical and thermal treatment. Recovered oil can be re-used to fuel the machine, enabling a more sustainable process.

Even as more technologies emerge into the marketplace, managing and navigating through the regulatory environment is becoming a significant issue. “The biggest challenge will be educating regulatory bodies around the world as more technologies come into the market that allow for reuse and recycling of drilling fluids and drill cuttings,” Mr Abbott said.

In some areas, for example, wastewater must be treated and disposed of as waste even after it has been purified. “We have technologies in place for water treatment that can treat water to drinking standards, but that technology cannot be used in certain areas because a particular region’s definition of ‘beneficial reuse’ is not fully established, or because the definition of ‘waste’ is so inflexible that recycling or reuse of waste is not permitted,” Ms Djuric noted.

HCB and SupaVac are Halliburton’s trademarks, and FullCircle is Halliburton’s registered trademark.

Original Article

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