1. Circulation of drilling fluid
   The circulation of drilling fluid is maintained by drilling pumps (commonly known as mud pumps). High-pressure drilling fluid discharged from the drilling pump passes through the surface high-pressure manifold, riser, hose, faucet, square drill rod, drill pipe, drill collar to the drill bit, ejected from the drill nozzle, then flowing upward along the annular space formed by the drill rod and the shaft wall (or casing), returning to the ground through the discharge line, vibrating screen flow into the mud pool, and then through the treatment of various solid control equipment back to the upper pool, into the recirculation, this is the drilling fluid circulation process and  Circulating system.
   

II. Function of drilling fluid
1. Carrying and suspended cuttings

The most basic function of drilling fluid is to carry the cuttings of the bottom hole broken by the bit to the ground through circulation, to keep the hole clean, to ensure that the bit always contacts and breaks the new formation at the bottom of the well, not to cause repeated cutting, and to keep safe and fast drilling. The drilling fluid can suspend the drilling debris retained in the well in the annulus, so that the drilling debris will not sink quickly and prevent the sand-sinking drilling.
 2. Solidify wellbore
Well-wall stability and well-hole rules are the basic conditions for safe, high-quality and fast drilling. The drilling fluid with good performance should be able to form a thin and tough mud cake on the shaft wall by means of liquid phase filtration, stabilize the drilled formation, prevent the liquid phase from invading the formation, and reduce the degree of hydration expansion and dispersion of shale.
3. Equilibrium formation pressure and rock lateral pressure
In the process of drilling engineering design and drilling, it is necessary to adjust the drilling fluid density continuously, so that the liquid column pressure can balance the formation pressure and the formation side pressure, so as to prevent the occurrence of downhole complex situations such as blowout and well collapse.

Other processing technologies

3.1 Demulsification: demulsification methods are mainly chemical demulsification, membrane demulsification, electric field demulsification, shear demulsification, heating demulsification, centrifugal demulsification, etc. Now more chemical demulsification is used, that is, adding demulsifier to emulsified oily drilling wastewater, through chemical action, supplemented by other separation methods, to achieve the purpose of emulsion de-stability, demulsification and oil-water separation. The chemical demulsification methods adopted at home and abroad mainly include salting-out method, acid-base method, condensation method and mixing method, but although these methods make the treatment effect remarkable, but because of the addition of chemical additives, the cost is increased, and the new impact on the environment is also brought.  　　

According to the characteristics of waste drilling fluid as water-based and oil-based mixture, an efficient and economical treatment process was adopted. The results show that the treatment technology can effectively separate the three phases of oil, mud and water in the waste drilling fluid, reduce the amount of sludge, improve the content of pollutants in the effluent, and basically meet the national solid waste discharge standard after treatment, which basically solves the problem of disposal and discharge of waste drilling fluid in oil fields.

 3.2 Mechanical Dehydration: This method is to separate the solid-liquid two phases from the waste drilling fluid by means of enhanced measures such as chemical flocculant deposition and mechanical separation. However, because of the different characteristics of drilling fluid produced by each oil field, a single flocculant can not make the drilling fluid of various properties carry out effective solid-liquid separation, and different flocculants should be used for different waste drilling fluids.　　

3.3 MTC (Mud To Cement) technology: the conversion of waste drilling fluid into cement slurry technology, referred to as MTC technology, which mixes waste drilling fluid with slag and uses activator to activate the solidified components in slag. With other additives to obtain various uses of cementing fluid. This technique has been studied extensively at home and abroad, and has been widely used. There are many advantages to cementing with it: low turbulent displacement, good compatibility with mud, short thickening transition time and static gel strength transition time. 　　

With the continuous development of oil fields, drilling waste treatment has higher requirements, China’s drilling waste treatment work can not be compared with developed countries, because of its late start, research and application is still in a relatively basic stage, the control and prevention of drilling waste liquid is still not in place, and there is still a big gap with the world’s advanced level, so we should increase the research on drilling waste liquid treatment and application, and strive to prevent drilling waste liquid as the focus of drilling pollution control.

2. Curing Method

Curing method is to add curing agent to waste water-based drilling mud or drilling mud sediment, so that it can be converted into soil-like solid (pseudo soil) landfill in place or used as building material, etc. This method can greatly reduce the erosion of soil by metal ions and organic matter in waste drilling mud, thus reducing the environmental impact and harm of waste drilling mud, and at the same time can ensure that waste drilling mud pool can be ploughed back at the end of drilling process.

 2.1 Cement curing technology: Cement curing is a treatment of cement as curing agent to solidify the waste slurry. Cement is an artificial inorganic cement material, the main components are SiO2、CaO、Al2O3 and Fe2O3.. There are many kinds of cement which can be used as curing treatment, the most common application is ordinary Portland cement. The curing principle is to form calcium silicate hydrate glue through silicate and water, and to form an object containing silicate fiber and hydroxide after solidification, to contain harmful substances, and gradually harden to form cement solidified body.

2.2 Lime curing technology: Lime curing is a method of curing waste slurry containing sulfate or sulfite with lime as main curing agent and active silicate as additive. The principle of lime curing is that in the presence of moisture, lime and silica-aluminate roots in additives react with the above type of waste mud, gradually coagulate, harden, and finally achieve curing.

2.3 Curing technology of fly ash: fly ash is a mixture of pozzolanic materials, mainly composed of potentially active impurities such as SiO2、Al2O3. The curing principle of fly ash is that, in the presence of water, silica and alumina are excited by alkaline substances in the mud to produce hydration hardening, stable hydration products (CSH and CAH,CAH) are generated by excitation, which will accelerate the reaction to form ettringite, further improve the gel composition and hardening quality of drilling waste mud system, and finally reach the curing target.

2.4 Water glass curing technology: Water glass is a soluble alkali metal silicate material made of alkali metal oxide and silica, which is a colorless and transparent viscous liquid. Water glass has hardening, binding, containment and other properties, can be used as cementitious materials. Water glass curing method is to use water glass as the main curing substrate, supplemented by inorganic acid substances (such as sulfuric acid, nitric acid and phosphoric acid), and then mixed with waste mud according to a certain proportion of ingredients, neutralization and condensation dehydration reaction, so that the harmful substances automatically dehydration, after condensation hardening, finally achieve curing.

With the continuous exploration of oil field reserves in China, the development strength of oil field has been obviously enhanced, and the number of oil wells is also increasing more and more rapidly. Because of the damage to the environment, the treatment technology of the waste produced during drilling has attracted more and more attention. Drilling fluid, as the main waste liquid to be treated in drilling process, has been widely used in pollution-free treatment technology of oil field waste drilling fluid because of the pollution and damage effect of some chemical components contained in it on the environment.

1 Recycling method

The waste drilling fluid can be reused after recovery, storage and treatment by transit station. This method not only avoids the damage of drilling fluid to the environment, but also effectively reduces the cost of drilling fluid in the process of reuse.

1.1 Mechanized recovery units are used to convert drilling fluid into dry-cured dry powder formulations and to reuse the cured dry powder formulations after hydration. Although the hydrated drilling fluids can not reach their original properties, their use as an aggravating agent is still very effective. This method uses more fuel and costs more in the process of curing the drilling fluid into dry powder formulations, which is also a disadvantage of this method.

1.2 Old well drilling fluid reuse technology: this technology is relatively simple, one well after the completion of the drilling fluid can be moved to another similar well to continue to use, then the drilling fluid only need to add some treatment agent to achieve the original performance for re-use. This method does not require mechanical equipment and fuel, the demand for personnel and equipment is low, the cost is low, and the pollution of drilling fluid to the environment is effectively reduced, so this technology has remarkable effect in terms of economic, environmental and engineering benefits. This method is most suitable for the area with high wellhead density. After the completion of the old well, the drilling fluid is transferred by transfer tank truck Using another field utilization, this method urgently needs to solve an urgent problem, that is, how to ensure the multiple reuse of drilling fluid with the minimum investment, which is the most promising and low cost method at present, effectively realizes the reduction of production cost and the improvement of economic benefit of oil wells.

To be continued

According to the mud properties of different mine sand washing plants, the use of different mud rapid precipitator products can effectively ensure the recycling of cleaning, rapid precipitation speed, flocculation tight. Compared with the present treatment process of mud wastewater from sand washing yard, the separation of mud water and flocculation sedimentation purification by using mud rapid precipitator has great advantages, which is manifested in the following aspects:

1. sewage treatment capacity is large: reduce the precipitation time of suspended matter, reduce the content of suspended matter in sewage and reduce the cost of sewage purification treatment, small area, low management costs. At present, the sedimentation tank sewage purification treatment system, which is widely used by mine sand washing field production enterprises, only depends on the gravity of fine particles for precipitation, its precipitation speed is slow and the precipitation time required is longer.
2. addition amount is less: using this product with a very small amount can play a good flocculation sedimentation effect, rapid precipitation.
   3. removal rate is high: the mud sand branch removal rate is more than 95%, the water in the clear liquid tank can be returned directly to the sand washing system, and the real zero discharge can be achieved. This product can be used for piling, mining, sand washing yard and other mud precipitation treatment.
   
3. Usage:
   1. the slurry rapid precipitator solid particles and tap water were stirred and dissolved into liquid state, which was directly added to the instantaneous precipitation in the mud wastewater of the sand washing field by the way of valve or metering pump. the dissolved concentration of the slurry rapid precipitator was generally 0.1%-0.2%.

2.for the uncertain sediment concentration in mud wastewater, the amount of addition should be determined by experiments.

3.for the treatment of different concentrations of sand washing wastewater, the amount of mud precipitator can be adjusted by field debugging.

Note: the amount of mud precipitator is determined with the concentration of sand washing sewage, if the amount of excessive, it will cause waste and will have a reaction, if the amount of mud precipitator is not enough, it will be difficult to produce precipitation, so the correct and reasonable control of the dosage, should first do a small test to determine the dosage in use.E

Mud precipitator is an organic polymer, which can quickly separate and precipitate all kinds of mud sewage and achieve the purpose of mud water separation. It is a good mud pressure mud dehydrator.

Mud precipitator, can be used for rapid precipitation of mud wastewater such as washing mud, sand washing mud, piling mud and so on. In the process of sand washing production in mine sand washing yard, a large amount of waste water, solid sediment and sludge will be produced. The main pollutants are a large number of sediment suspensions with different particle sizes. Generally, more than 2 sedimentation tanks are used to filter out larger suspended matter or particles.

Mechanism of sedimentation agent action: it is very practical and simple to make rapid flocculation sedimentation of mud wastewater adopt mud rapid sedimentation agent, mud rapid sedimentation agent also known as mud precipitator, mud sewage flocculant, in the sand washing mud wastewater treatment process due to different water quality, composition, need to choose the corresponding mud rapid sedimentation agent products, can quickly adsorb suspended matter in mud wastewater to form condensed particles, these flocs in the process of settling, will catch new mud particles, and become a tight structure of large flocs after collision.

Experimental selection: in order to speed up the sedimentation rate of mud waste water in mine, sand washing yard and other production processes, reduce the sedimentation time of sediment, reduce the content of suspended matter in sewage and reduce the cost of sewage treatment, the types, structure, molecular weight and ionic strength of mud precipitator, dehydration and peeling property of filter https://www.gnseparation.com/are different. In practical production, in order to select the appropriate slurry rapid precipitator and its addition amount, the following methods are usually used to determine.

1. In the beaker containing sewage such as crazy or sand washing yard gradually add mud precipitator after stirring.
2. When the amount of its addition reaches a certain value, the flocs formed by flocculation in the mud sewage begin to disperse again, and the quantitative value is the appropriate amount of the slurry rapid precipitator. After many tests.
3. Appropriate amount of mud precipitator and its addition can be selected.

The slurry flocculant can adsorb and bridge the solid particles or aggregates in the slurry, so that the fine particles can be bridged into flocs of large particle groups, so as to achieve the purpose of self-gravity settlement or removal by mechanical equipment.

At present, the technological process of sand mechanism sand in China is as follows: the pebbles or ores are broken by crushing machinery, and the sand and stone are washed by sand washing equipment to obtain fine sand with less mud content. This process produces a large amount of sewage, the main pollutant is sediment, in which sludge suspended in the water, difficult to settle, direct discharge of water pollution is serious. At present, the sedimentation tank method used in the industry covers a large area, treatment time is long, sediment extraction is not easy, tank car transport method, high cost, can not fundamentally solve the problem.

In recent years, most of them have adopted this kind of process system, such as mud water collection sedimentation tank, secondary settling tank, clear liquid tank, mud sand separation system, dosing system, drainage system and slag discharge system. The working principle is as follows: the mud water is collected into the sedimentation tank through the pipeline, and pretreated by the mud dehydrator to remove most of the fine sand and part of the mud in the mud water, and the filtrate enters the secondary settling tank through the drainage system. The mud water of the secondary settling tank is suspended mud, and the specific gravity difference with water is very small, it must be treated with flocculant. After the mud water is treated by dehydrator, the mud sand branch removal rate is more than 95%, and the water in the clear liquid tank can be returned directly to the sand washing system, and the real zero discharge can be achieved.

Slurry flocculant is usually used with water ratio between 0.1% and 0.3%, then after mixing dissolved into glue-like water, then added to the mud sewage sand washing circulating water outlet for mixing, can quickly precipitate the suspended matter in the sewage in a few seconds, sand washing yard mud sewage is a kind of water containing fine mud particles suspended matter, and the amount of mud content is very high, so it is recommended to do a small test, determine the proportion of mud precipitator after adding, can be large quantities of sediment washing.

Mud treatment equipment as a kind of separation device used to treat mud and separate liquid and solid in various sectors. Due to the facts that mud usually has the property of corrosiveness, or the treatment equipment has been in service for a certain period, some improper operation is made in use or other reasons, it is avoidably easy to cause some malfunctions or equipment failure, resulting to the device cannot work properly as expected. What are the common failures of mud separation equipment? What should be done when the mud separation equipment fails? Here are listed some common failures and corresponding repair methods for your reference.

1.Mud separation equipment idling
If the main motor idling occurs during the operation of the mud separation equipment, the power supply should be cut off first in this situation, and then the cover should be opened to check whether it is due to the material stuck in the equipment.

2.The effect of mud dehydration weakened compared with before
When the separation equipment is not able to handle the mud at run time to achieve the previous separation effect, operator can try to change a parameter at a time, or do some simple debugging to see if the failure can be accordingly solved or not. If not, then turn to the technical staff or the equipment supplier for help, and the pre-requisit is to ensure safety.

3.Mud separation equipment stops running for unknown reason.
In response to this situation, new mud separation equipment accessories can be used to replace suspicious accessories for testing, which is a relatively simple and effective treatment methods. Such method is suitable for some circuit board systems and other aspects of the problem solving. If the replacement of suspicious parts with new components can not solve the existing malfunction, operator should get the original parts back, which is less costly and more effective.

The above introduces several common failures of mud treatment equipment. In addition to the timely solution after the failure, in order to ensure the normal and safe use of mud separation equipment, operator should also carry out routine maintenance, carry out refueling maintenance for rotation of the fittings once a month , and at the same time check the lubrication of the bearing operation whether there is wear phenomenon, or whether the parts in the brake device is worn. Seriously worn parts should be replaced in time.

The mud treatment equipment produced by GN has the advantages of strong environmental adaptability and low failure rate, and generally has low requirements for the working environment and operators. If there are minor failures in peacetime, attend it timely repair, do a good job of maintenance, and the basic equipment can ensure a long service life.

Mud Gun is designed for users to mix and suspend particles in a solids control system. Mud Gun can prevent the mud from precipitating. It is a very simple tool and easy to operate. It is usually we operate with mud agitator; agitator should place at tank center and mud gun at the tank corners. This will reduce solids build up in tank corners. Size of the tank will determine the number of mud gun to be used.

There are many different designs of mud guns. GN Mud Gun design comes with 3 nozzles. Customer can choose the nozzle size is 2” (DN 50) or 3” (DN80). Also, two styles of the structure, one is fixed (0 degrees) the other is rotary (360 degrees).  Build for tough task purpose GN Mud Gun designed with strong materials with affordable price. GN Mud Gun is the best product to have in your solid control system.  

GN Mud Agitator

Mud agitator usually mounted on mud tank for mix the drilling mud to avoid the drilled cuttings and refined solids from the settlement. Each large compartment of storage tank should be equipped with mud agitators to keep the appropriate drilling mud that will draw out to the borehole.

GN horizontally mounted agitator included an explosion-proof motor, coupled to a gearbox that drives the impeller shaft. The impellers (turbines) transform mechanical power into fluid circulation or agitation. The objective is to obtain a uniform suspension of all solids. Motors range from 4 to 30 HP and Horsepower may be de-rated for 50Hz or 60 Hz power configuration. Available horsepower ratings are: 4, 7.48, 10, 15, 20, 25, and 30.

Why chose GN Mud Agitator? It is lightweight, low noise, explosion-proof electric motor, high efficiency of transmission and strong horsepower agitator.  

GN Waste vacuum pump, also named as a solids transfer pump. With special structure design, it can be used on tough environmental for solids transfer, high working performance, and less maintenance. The pump can transfer materials with high gravity and high density, solids content transfer rate max up to 80%. It has following features: the high efficiency Venturi device can produce vacuum up to 25 feet HG (Mercury Column). This is equivalent to vacuum of 85Kpa to remove the material. The pump structure is simple and compact, almost none of wear parts. The transfer distance is up to 500-1000 meters.

The GN Waste vacuum pump can transfer materials applications

Waste mud and waste solids discharged from shale shaker, mud cleaner, and centrifuge transfer

Drilling mud transfer

Waste pit cleaning

Hazardous waste recovery

Oil sludge, tank bottoms residual removal and transfer

Barge holdings and vessel bottom cleaned

Bulk tank and silo transfer of material

Sand; Course, fine, conventional and frac sand

Diatomaceous earth

Animal waste, etc.

The GN solids transfer pump has three models, GNSP-10B, GNSP-20B, and GNSP-40B.

Max capacity from 10m3/h, 20 m3/h and 40m3/h.

Pressure request: GNSP-10B and GNSP-20B is 550 Kpa-690 Kpa (80-100 PSI), GNSP-40B is 550 Kpa-785 kpa (80-114 PSI).

Air Demand: GNSP-10B 4.3 m³/min (150 CFM) GNSP-20B 8m³/min (280 CFM) GNSP-40B 17m³/min (600 CFM).

Weight: GNSP-10B 705.5 Lbs GNSP-20B 850. Lbs GNSP-40B 1966.6 Lbs

Dimension:L×W×H: GNSP-10B 1283×800×1370mm GNSP-20B 1421×900×1448mm GNSP-40B 1690×1468×1983mm

GN Provide OEM service with customized design to protect the customer brand. 

GN Solids America Main Products Application

OIL & GAS Drilling—-Mud Solids Control & Waste Management

HDD & CBM Drilling —-Mud Recycling System

Mining & Industrial—-Slurry Separation Plant

For more information, please contact GN sales representative at the Web: www.gnsolidsamerica.com/ www.gnsolidscontrol.com

Add: 6710 Windfern Rd, Houston, TX 77040

TEL: 832 288 5917