Month: October 2014

By accelerating mud through a curved vessel, solids and mud are separated according to Stokes Law. These solids are passed over a screen to recover excess fluid. Function The mud cleaner is a solids separation device that combines a desilter with a screen device. The mud cleaner removes solids using a two stage process. First, the drilling fluid is processed by the desilter. Second, the discharge from the desilter is processed by a high-energy, fine mesh shaker screen. This method of solids removal is recommended for muds containing significant amounts of weighting materials or having expensive fluid phases.

Note: When recovering weight material with a mud cleaning system, be aware that any fine solids that go through the cleaner’s screen are also retained in the mud. Over time, the process can lead to a fine-solids build-up.

Trouble shooting for mud cleaners

Since the mud cleaner is both a hydrocyclone and a shaker, many of the operating guidelines listed for these devices apply to mud cleaners. A decrease in solids coming off the screen may indicate a torn screen, which should be replaced immediately. Plugged cones or large solids coming off the screen can imply a problem with the upstream shale shakers. The likely causes are bypassed screens, torn screens or dumping the shaker box into the active system. The desander cones on the mud cleaner should be 6 in. diameter or smaller. The median cuts of larger cones are too coarse to be useful.

Performance operation of mud cleaner

If a mud cleaner were to be utilised, a number of areas should be addressed:

• The unit should be installed in such a way that access, both for monitoring and maintenance purposes is adequate.

• It is extremely important that the centrifugal feed pump is correctly matched to whatever mud system is in use, so as to guarantee the correct feed pressure.

• Impeller size and condition is critical to operational efficiency. Any found to have seriously washed blades should be replaced at the earliest opportunity.

GN Solids Control is an expert in mud system for tunneling. Just a week ago, GN delivered a set of mud system with dewatering unit to a Singapore customer. Besides, mud system for tunneling, GN also provides mud system for HDD, solids control system for oil and gas drilling.

Dewatering unit is equipped to separate extremely fine particle in the drilling mud to lower the proportion, thus ensuring the high performance of drilling fluids.

 Sometimes, we do not need dewatering unit for the processed mud with particles over 5 microns being removed out is satisfying, but if not, we need this unit to separate finer solids out to meet the requirement for drilling, that’s why we need it in this system. This dewatering unit is a suitable solution.

 GN Dewatering Unit Configuration as below:

1. Coarse Solids Separation System
GN’s dewatering unit is specially for drilling project, thus before the dewatering unit, there is a 2-stage drilling mud recycling system including 1 unit GNZS705-HB shale shaker with double layers screen. And 1 unit GNZJ703E-3S desander unit. With the two equipment, large size solids are removed out.

2. Two Tank Compartments PAM Mixing Unit 
GN’s PAM mixing unit has adopts 2 tanks design with a pre-mixing tank on top. The flocculate dry powder is added from the hopper on tank top and then delivered to pre-mixing tank. As per the response from the level gauge located in either mixing tank, the pre-mixed chemicals would flow into the mixing tank for full mixing and storage. All process here for chemicals mixing is automatically controlled.

3. Dewatering Decanter Centrifuge. 
Used as dewatering centrifuge, GNLW553G separates flocculated colloidal particles. There are two screw pumps, one feeds flocculants to the centrifuge, one feeds active mud to centrifuge. The two feeding process are done at the same time, so the unltra fine solids will be flocclulated larger and then separated out.

Composed of the three main parts, GN made mud system will enjoys a high performance.