1. Project Overview
This project involves the construction of a large-scale, modern resource utilization production line specifically designed to address the challenges of disposing contaminated soil and sludge in Shandong Province, a major industrial and agricultural region. Provided as a full-line EPC turnkey service by Zhengzhou Mining Machinery, the project aims to transform waste contaminated soil and sludge into valuable ceramsite products through advanced production technology, achieving "turning waste into treasure" with significant environmental and economic benefits.
Designed Capacity:Annual output of 200,000 cubic meters of ceramsite.
Input Materials: Solid wastes such as contaminated soil, municipal sludge, and river dredging sludge.
Core Objective: Achieving the harmless treatment, reduction, and resource utilization of solid waste.
2. Core Solution & Technical Highlights
Zhengzhou Mining Machinery provided a tailored overall solution for this project. Its technical core lies in the successful integration and optimization of advanced processes from the metallurgical, chemical, and building materials industries, leading to the following key technologies and equipment:
2.1. Targeted Process Design: Customized pre-treatment, proportioning, calcination, and cooling schemes were designed based on the characteristics of contaminated soil and sludge, such as complex composition, high moisture content, and fluctuating calorific value, ensuring thorough decomposition of pollutants and stable product performance.
2.2. High-Efficiency & Energy-Saving Equipment: The production line uses independently developed high-efficiency rotary kiln systems, known for high thermal efficiency, stable operation, and low energy consumption. Matching intelligent coolers enable heat recovery, further reducing system energy consumption.
2.3. Environmental Protection & Automation: The entire line is equipped with advanced environmental protection facilities, including dust removal and desulfurization/denitrification systems, ensuring exhaust gas emissions meet standards. Key processes employ automated control to enhance production efficiency and product consistency.
3. Detailed Process Flow
The production process for this project is mature and efficient, involving the following specific stages:
3.1. Raw Material Pre-treatment:
Breaking & Crushing: Lumps of clay, contaminated soil, and dried sludge are broken down and crushed to ensure uniform particle size.
3.2. Batching & Homogenization:
Proportioning & Metering: Different raw materials are precisely metered and mixed according to scientific ratios based on their composition to ensure stable chemical composition and firing conditions for the ceramsite.
Mixing & Stirring: The proportioned raw materials are thoroughly mixed with water to form a uniform paste.
Aging: The mixed paste is stored in an aging yard for a specified period, allowing for more even water distribution and improved plasticity, which benefits subsequent pelletizing.
3.3. Forming & Thermal Processing:
Pelletizing: Specialized pelletizing machines form the aged paste into uniform green pellets.
Calcination: The green pellets enter the rotary kiln and are calcined at high temperatures between 1150-1250°C. This is the key stage where the ceramsite expands, forming a porous structure, and where organic matter is thoroughly decomposed, and pollutants like heavy metals are solidified.
Cooling: The high-temperature fired ceramsite enters an efficient cooler for rapid quenching, setting its structure and achieving final physical strength. The recovered hot air can be redirected to the kiln, saving fuel.
3.4. Finished Product Handling:
Grading & Screening: The cooled ceramsite is classified into different size fractions (e.g., 10-20mm, 5-10mm) using multi-layer vibrating screens.
Storage & Bagging: The graded finished ceramsite is conveyed to storage piles or directly enters an automated bagging system for packaging, facilitating storage and transportation.
Process Flow Diagram:
Raw Materials (Contaminated Soil/Sludge) → Breaking/Crushing → Proportioning/Metering → Mixing/Stirring → Aging → Pelletizing → Calcination → Cooling → Grading/Screening → Finished Product Storage/Bagging
4. Project Achievements & Far-Reaching Impact
4.1. Environmental Benefits:
Waste Treatment: Processes large volumes of contaminated soil and sludge annually, effectively resolving local environmental pollution issues.
Resource Recycling: Transforms waste into valuable building materials, reducing the need for mining natural resources.
Energy Saving & Emissions Reduction: The production line itself emphasizes energy-efficient design, and the produced lightweight, insulating ceramsite products contribute to energy saving and emissions reduction in the construction sector.
4.2. Economic Benefits:
Value Creation: The annual output of 200,000 cubic meters of ceramsite generates substantial direct economic revenue.
Cost Reduction: Offers lower long-term costs and better economic returns compared to traditional disposal methods like landfilling or incineration.
Broad Product Application: The produced ceramsite can be used as a lightweight aggregate in lightweight concrete, building blocks, landscaping, and soilless cultivation, indicating broad market prospects.
4.3. Industry Demonstration Effect:
The successful operation of this project provides a replicable and scalable model and benchmark project for the resource utilization of similar solid wastes nationwide, demonstrating the feasibility and advancement of the technical route.
5. About Zhengzhou Mining Machinery
As the EPC contractor for this project, Zhengzhou Mining Machinery leveraged its core strengths in "Innovation, Quality, Service" to ensure the smooth progress of the entire process from planning, design, manufacturing, installation, commissioning, to personnel training and technical support. This project fully demonstrates Zhengzhou Mining Machinery's professional capability and leadership in the field of solid waste resource utilization equipment manufacturing and complete line solutions.
