Core Breakthroughs of Mud Non-Landing Technology: From Solid-Liquid Separation to Resource Utilization

In fields such as oil and gas exploration and infrastructure construction, mud treatment has long faced challenges of pollution 

and compliance: traditional landfilling methods are prone to causing soil heavy metal pollution, while direct discharge violates 

the Solid Waste Pollution Environment Prevention and Control Law of the People's Republic of China.

With the advancement of the 'waste-free city' initiative, mud treatment is shifting from 'end-of-pipe governance' to 'source 

control + resource recycling'.

This article will analyze how modern mud treatment technologies achieve the environmental goals of '80% reduction in waste 

volume and 85% resource utilization rate' through a three-stage separation system, as well as their innovative applications in 

engineering practices.

I Solid-Liquid Separation: Solving the Core Challenge of Mud Treatment Mud is essentially a complex three-phase system of 'solid-liquid-gas,' containing drill cuttings (20%-40%),

water (50%-70%), and chemical additives. Traditional natural sedimentation methods take more than 3

days and have insufficient separation precision. Modern treatment technologies achieve efficiency

breakthroughs through a three-stage gradient separation system:

1. Physical Screening: Rapid Separation of Coarse Particles High-frequency vibrating drying screens (working frequency: 25-35Hz) use multi-layer stainless steel

screens (aperture: 0.074-2mm) to complete preliminary screening of single batches of mud

in a short time, separating drill cuttings with a particle size ≥74μm and reducing the water content to

below 35%. This step is equivalent to 'sieving' the mud to remove large-particle impurities

first, reducing the burden on subsequent processing. 2. Centrifugal Separation: Precise Capture of Micron-Sized Particles In a horizontal spiral centrifuge (rotation speed: 3000-4000rpm), dynamic separation of fine

particles (0.5-74μm) is achieved using centrifugal force (separation factor: 2000-3000G). By adjusting

the drum-spiral differential speed through an intelligent variable frequency system, the centrifuge adapts

to mud of different densities, achieving a solid-phase recovery rate ≥98% and a solid

content in the separated liquid phase<5‰. This is akin to using a high-speed 'spin dryer' to fine particles

from the mud. 3. Filter Press Curing: Deep Extrusion of Residual Moisture After chemical conditioning (adding high-efficiency flocculants, with a 30% reduction in dosage compared

to traditional agents), the mud enters a chamber filter press. Through 1.2MPa high-pressure diaphragm

extrusion, it finally forms mud cakes with a water content ≤20%, reducing the volume by 70% compared to

the original mud. This step is similar to 'juicing,' squeezing out as much water as possible from the mud to

make the mud cakes meet the landfill requirements of the *General Industrial Solid Waste Storage Standards*.

II. Resource Utilization: The Transformation from Pollutants to Industrial Raw Materials Breaking through the traditional mindset of 'treatment equals disposal,' modern technologies enable full-chain

resource utilization of mud components: 1. Value-Added Utilization of Solid Phase: Diverse New Uses for Drill Cuttings Construction Aggregates: Water-based drill cuttings without heavy metals (accounting for approximately 60%) are crushed and

screened (particle size ≤5mm) and then calcined at high temperature (800℃),

replacing 30% of natural sand and gravel for road bases. Practices in an oilfield show that treating 120,000 cubic

meters of drill cuttings can replace 48,000 tons of sand and gravel,

equivalent to reducing mountain mining by 2,400 cubic meters and saving 8,000m³ of landfill space. Sintered Brick Making: Drill cuttings with a clay content ≥40% are mixed with fly ash and coal gangue at a ratio of 1:1:0.5 and fired at 1000℃

to produce standard bricks. Tests show that the brick compressive

strength ≥MU15 (equivalent to C30 concrete strength) and water absorption<10%, which have been applied in

municipal engineering, realizing the circular economy of 'turning solid

waste into building materials.' Oil-Based Drill Cuttings Recovery:Solvent extraction technology (extractant circulation rate 95%) is used to separate

mineral oil from oil-based drill cuttings (recovery rate ≥85%).

The regenerated oil can be directly reused for drilling fluid preparation, and the remaining solid phase is stabilized

and used as road filling material, achieving 'oil-solid' dual recovery.

2. Closed-Loop Liquid Phase Circulation: Three-Stage Purification of Wastewater Primary Physical Treatment: Air flotation devices remove floating oil and suspended solids, reducing SS (suspended solids) from 5000mg/L

to below 500mg/L, equivalent to 'filtering impurities' from the wastewater. Secondary Chemical Oxidation:Adding a composite oxidizing agent (reaction time: 60 minutes) reduces

COD (chemical oxygen demand) from 3000mg/L to 500mg/L, while removing more than 90% of heavy

metal ions, completing 'chemical disinfection.'Tertiary Membrane Treatment:The ultrafiltration + reverse

osmosis combined process (membrane flux: 15L/㎡・h) ensures the effluent meets the *Industrial Water Quality

Standards* and can be 100% reused for drilling fluid preparation and site dust suppression, achieving 'zero

wastewater discharge.'

IV. Engineering Practices: Technology Implementation from Oilfields to Tunnels In the development of shale oil in a certain oilfield, for high-viscosity mud with a sand content of 25%-30%,

the combined process of 'vibration screening + horizontal spiral centrifugation + plate-and-frame pressure

filtration' was adopted. The single-well treatment time was shortened from 4 days to 18 hours, ensuring a 20%

improvement in drilling efficiency. The treated drill cuttings were used to produce 32 million standard bricks,

replacing 12,000 tons of coal and reducing CO₂ emissions by 32,000 tons—equivalent to the carbon sequestration

capacity of planting 178,000 fir trees.

In the urban infrastructure sector, a multi-stage mud treatment system applied in a tunnel construction project solved

the pollution problem of bentonite mud in shield tunneling through the 'no mud on the ground' technology,

achieving 'no slurry outflow, no water waste,' and providing an environmental protection model for engineering

construction in complex urban environments.

Conclusion: The Environmental Economics of Mud Treatment The breakthrough in mud non-landing technology essentially represents a win-win situation for environmental protection

and the economy: through technological innovation, it not only solves the environmental problem of 'where the pollution

is' but also addresses the development proposition of 'where the resources go.'

When every cubic meter of mud can be transformed into building materials and every drop of wastewater can be recycled,

the contradiction between industrial production and ecological protection is being gradually resolved by technological

progress. With the advancement of the 'double carbon' goals, this 'cradle-to-cradle' circular economy model is becoming

the inevitable path for the green transformation of traditional industries.