What C&D materials can a jaw crusher process?
The CT-series jaw crushers handle concrete (reinforced and unreinforced), masonry block, cinder block, brick, ceramic tile, and natural stone. The CT-740 and CT-850 also handle hard rock — granite, basalt, dolomite, and limestone. Rebar and wire mesh pass through the jaw chamber and are separated by the cross-belt magnet. None of the CT-series crushers process asphalt, drywall, wood, plastics, roofing material, insulation, or hazardous materials. These must be separated from the feed before crushing.
What materials must be removed from C&D debris before crushing?
Drywall and gypsum board, treated and painted lumber, dimensional lumber, plastics, roofing material and asphalt shingles, insulation (fiberglass, foam), and any material with suspected hazardous content (asbestos, lead paint, PCBs) must all be removed before feeding the crusher. These materials either contaminate the output, do not crush, or create regulatory issues. The pre-sort — typically done with an excavator before loading — is the most important step in a C&D processing operation.
Does processed mixed C&D aggregate meet road base specification?
Output from a clean, well-sorted mixed C&D feed — primarily concrete and masonry without significant contamination — may meet road base gradation for some applications. It cannot be guaranteed without material testing from your specific feed. For DOT bid work requiring certified aggregate, test the output from your feed before specifying it. For structural fill, drainage aggregate, and sub-base applications on private site work, mixed C&D aggregate at road base gradation performs the function without formal DOT spec certification in most cases.
How does the CT-850 by-pass conveyor help on mixed C&D feeds?
On a mixed demolition debris load, a portion of the material is often already at or below the target output size when it enters the hopper — broken block fragments, small concrete pieces, and masonry rubble that is already within spec. The by-pass conveyor routes that material around the jaw chamber and directly to the discharge belt, maintaining throughput without crushing material that does not need crushing. On a clean concrete feed, the by-pass is used less. On a mixed feed with significant variation in piece size, the by-pass contributes more to throughput and reduces unnecessary wear on the jaw plates.
What is the difference between C&D waste processing and concrete recycling?
Concrete recycling refers to processing a feed that is primarily or exclusively concrete — typically from a known demolition source where the material type is consistent. C&D waste processing refers to mixed demolition debris that includes concrete, masonry, block, brick, and hard rubble in combination. The jaw crusher circuit handles both applications, but C&D waste requires a pre-sort to remove non-crushable materials, produces less uniform output, and typically generates aggregate with a lower market value than clean crushed concrete. For the concrete-specific output guide, DOT spec guidance, and jaw vs. impact comparison, see the Concrete Recycling page.
Can drywall go through a jaw crusher?
No. Drywall must be removed before feeding the crusher. Gypsum does not process cleanly in a jaw crusher and contaminates the fines fraction in the output. Gypsum-contaminated aggregate can fail structural fill specifications and may create disposal complications in some jurisdictions. On a demolition job, remove all drywall from the debris pile before loading the crusher.
How do I handle a mixed feed of concrete and masonry in the same load?
Concrete and masonry process together in the CT-series jaw crushers without separate handling — both materials are crushable through the same jaw chamber at the same CSS setting. Masonry is softer than reinforced concrete and fractures at lower force, so mixed feeds of both materials run cleanly. The practical challenge with truly mixed loads is piece size variation — concrete sections from commercial demolition are often larger than masonry sections, and the larger pieces determine your feed size requirement. Size the crusher to the largest piece, not the smallest.
What is the minimum project volume that justifies a C&D crushing circuit?
The economics depend on your disposal rate and distance to the nearest accepting facility. At mixed C&D tipping fees of $60 to $120 per ton, most contractors find the circuit pays at volumes above 150 to 200 tons per project or location. Below 100 tons on a single site, mobilizing the crusher and screening plant may not recover the mobilization cost before the job is complete. For contractors running multiple demolition projects within a geographic area, aggregate volume across the season — not individual project size — is the better measure of whether a crushing circuit makes sense.