High-Efficiency Mud curing agent For Volume Reduction And Stabilization

Mud curing agent

I. Summary

1.1 Current situation of sludge treatment and disposal in China

Sludge treatment: sludge volume reduction, volume reduction, stabilization and harmless treatment process.

Sludge disposal: the final way of absorbing the treated sludge or sludge products to achieve long-term stability in the environment or long-term utilization, without harmful effects on human health and ecological environment.

1.2 Sludge disposal plan

In terms of final disposal of sludge, currently effective methods include landfill, incineration, fertilizer utilization, construction material processing, etc.

From the perspective of resources, the first consideration is the utilization of materials, which are generally used for composting; The second consideration is energy utilization, mainly drying and incineration; Landfill is not available, but it will occupy land resources.

Landfill: a common sludge disposal method in China. An important transitional approach in a short time. Due to the difficulty of operation and the pollution of leachate to the environment, this method will eventually be eliminated.

Utilization of building materials: mainly used as concrete additives and bricks. Due to the congenital defect of the process, there is the problem of odor disturbing the people.

Incineration: sludge capacity reduction is large, and organic matter thermal decomposition is complete, realizing the concept of "energy saving, emission reduction, and circular economy". It is also not applicable in the case of low calorific value.

II. Introduction to curing technology

Mud curing agent is a universal inorganic salt compound, which is mainly used for dehydration, drying, solidification and hardening treatment of various cement containing soils (such as drilling mud rock cuttings, river, lake and pond sludge, coastal mudflat, domestic and municipal sludge, piling mud, tunnel construction mud, etc.), and can achieve the effects of sludge reduction, high-strength solidification and waterproof. Sludge and sludge can be treated for environmental protection during treatment, which is in line with the national strategy of recycling waste and greening the homeland of the motherland. Its high engineering performance, low production cost and sufficient supply are of great strategic significance to the sustainable development of the economy and suitable for large-scale engineering applications.

III. Physical and chemical indicators

Table 1 Physical and chemical indexes of Mud curing agent

IV. Product function

4.1 Make a variety of sludge into recyclable soil or plantable soil.

4.2 Improve the unconfined compressive strength of soil, increase its hardness and waterproof effect.

4.3 The improvement of soil pollution can stabilize and immobilize heavy metals and reduce leaching COD.

4.4 Remove the odor of sludge.

V. Product features

5.1 Short curing time and fast molding

① By combining with the water in the mud, the fluid mud with a water content of about 80% can be thickened and lose its fluidity after adding. After drying, the water evaporation can be accelerated and the drying and dehydration speed can be accelerated.

② After adding, the water loss rate can be accelerated in the natural state, and the requirements can be met without using the drying equipment. If a small amount of drying agent is added when using the equipment for drying, the processing speed can be greatly accelerated and the heat consumption can be reduced.

③ Mixing can be completed by using conventional equipment such as excavators, without using professional mixing equipment. The effect is better with professional mixing equipment.

5.2 Drying time: varies according to water content. The drying speed is greatly affected by the weather. The drying speed of dehydration is accelerated under dry, low humidity and high temperature conditions, and on the contrary, it takes longer time.

5.3 Universality: inorganic non-metallic curing agent, without pollution, has universality for corresponding materials.

5.4 Low cost and low dosage: generally about 5% of the sludge volume or the dosage can be adjusted according to the situation of small-scale test.

5.5 High compressive strength

① Adjusting the addition amount according to different soil conditions can promote the rapid improvement of compressive strength

② The added product can accelerate the volatilization of water and increase the overall strength of sludge. It is a very good choice for pit type direct curing.

5.6 Waterproof and anti-slurry property: it is universal for sludge and improves the waterproof property of solidified sludge. After addition, the sludge properties can be completely changed, and the clay will lose its pulping property. The direct appearance is that the treated sludge has good permeability and good water-repellency, and will not be sticky after adding water or soaking in rain, and at the same time, it will dry again quickly.

5.7 Curing strength

Mud curing agent can not only be used as mud dewatering and drying agent to improve drying speed, waterproof and strength, but also directly build roads with solidified sludge as subbase, base and pavement.

VI. Reaction mechanism

Without curing agent Add curing agent

Fig. 1 Reticular crystal formed by mud particles treated with

Mud curing agent(microscopic morphology)

This technology takes place a series of physical and chemical reactions between sludge and curing agent. On the one hand, the colloidal properties of sludge will be destroyed immediately after the addition of solidification agent, and the capillary channel will be rapidly established, increased and diffused, so that the internal water diffusion and volatilization channel of sludge will be opened, which is conducive to the rapid drying of sludge. At the same time, the curing agent hydrolyzes and hydrates the free water in the sludge and the attached water released by the gel breaker, producing a large number of gelatinous substances and chain-like crystalline substances, making the sludge form a compact and slightly porous overall micro-honeycomb structure, changing the soil properties, making the sludge have certain structural strength, waterproof, rapid drying and other characteristics.

VII. Treatment scheme

7.1 Addition amount of solidified agent with different water content of sludge

The specific dosage of the mud curing agent is determined according to the water content of the mud (refer to the data in Table 2). The actual dosage is determined according to the test data due to the different properties of the mud. Use mixing equipment such as excavator to mix evenly, make the curing agent fully contact with the sludge, conduct physical and chemical reactions such as gel breaking and hydration, and conduct static curing. After reaching the required water content and hardness requirements, the next treatment can be carried out.

Table 2 Solidifying agent dosage under different sludge water content

7.2 Construction method

Measure earthwork——Determine water content ——Calculation curing agent dosage——

Spreading curing agent ——Stir uniformity——Clap or compaction——Quiet cruing.

Step 1 Measure earthwork Step 2 Determine the water content of mud

Step 3 sprinkle the calculated curing agent Step 4 Fully mix with excavator

Figure 2 Construction flow chart of curing agent

According to different purposes of sludge treatment, in-situ treatment or ectopic solidification treatment can be carried out. After adding curing agent, excavators are used to stir the sludge in case of large amount of sludge, so that the curing agent can fully contact with the sludge for gel breaking and hydration reaction; After curing, the mud is gradually dried and hardened, and the water content is reduced, which can meet the curing requirements of different types of mud. It will take about 72 hours for the plain soil slurry with water content of about 80% to be transported after solidification. It takes about 3-7 days to reduce the water content to about 15%; Other types of mud have different time. Under the condition of non-pressure curing, the unconfined compressive strength can reach 100-500kPa, and the pressure curing can reach higher strength requirements.

7.3 Construction machinery

The construction machinery shall be determined according to the construction depth and engineering cost accounting, and the ordinary excavator can be used at a depth of about 1 meter; The deep layer can be solidified layer by layer with ordinary excavator, or the construction can be carried out after the excavator is equipped with a powerful mixer head.

7.3.1 Use ordinary excavator for shallow sludge treatment

7.3.2 The deep sludge uses a strong mixing system

VIII, Product advantages

① Low operation cost: low dosage, low cost, easy transportation, reduced turnover cycle and reduced safety risk.

② Green and environmental protection: the solidification strength of solid waste can meet the requirements of national standards. After treatment, the solidified material is waterproof and impervious, and has strong stability of heavy metals. It can realize harmless and reduced sludge treatment.

③ Accelerate the drying speed of waste: the unique advantages of this agent, such as sludge gel breaking, rapid loss of fluidity, rapid dehydration and drying, and high compressive strength of the treated products, are not possessed by any other curing agent.

④ Wide range of application: this product can be used for solidification treatment of river pond sludge, municipal sludge, piling mud, tunnel construction mud, oil field mud and rock cuttings.

Ⅸ. Packaging and storage

50 kg/bag or 1 ton bag, plastic woven; Sealed and stored in a cool and dry place with a shelf life of 12 months.

50 kg/bag 1 ton/bag (20 small bags inside)

1 ton/bag (bulk cargo)