china Henan Ruiyao Intelligent Environmental Protection Co., Ltd Company News

The Numbers From Retrofitted Plants Practice at a number of brick plants now provides a clear benchmark for closing process gaps. After converting an old two-stage flowsheet to a corrected configuration, the largest single change reported is in the raw material preparation section: hourly output rises by roughly 25 percent, while production cost in that same section falls by about 15 percent. Those two figures move in opposite directions for a reason. Higher output comes from removing the cushioning fines and the pointless recirculation; lower cost comes from spending energy once on material that genuinely needs reducing. Neither improvement depends on running the line harder. Reported Retrofit Results IndicatorBefore RetrofitAfter Retrofit Hourly output, raw material sectionBaselineUp approximately 25% Production cost, raw material sectionBaselineDown approximately 15% Crusher dutyMixed feed plus circulating loadMatched to stage design Downtime tied to the bottleneckFrequentReduced Why Owners Resist, and Why the Logic Is Changing Brick plants are currently operating under severe pressure. Many have closed, and those still running are doing so on thin margins. Every owner knows where the defects in the process sit. Yet most decline to fix them, and the reasoning is understandable: a retrofit requires capital, and money already earned is difficult to commit to an enterprise that is not currently earning well. That reasoning treats the retrofit as an expense. In the current market it is more accurately understood as the cost of remaining competitive. The same argument applies at the level of the individual plant and at the level of the industry. The Health Argument There is a simple analogy worth considering. The only reliable route to a long life for a person is a strong and healthy body; nothing else substitutes for it. A business is no different. An enterprise that intends to survive long term must first make itself structurally sound, so that when a crisis arrives it can clear obstacles that stop others. When a plant's production cost sits at the lowest level in its region, it gains something more valuable than profit: room to manoeuvre. That margin of survival, not the profit line, is what decides which plants remain operating after a downturn. What the Shift in Cost Means In the earlier market: production cost determined how much profit a plant made. In the current market: production cost determines whether the plant continues to exist. Treating the Flaw as Capital, Not Expense A flawed flowsheet is not a fixed characteristic of a plant. It is a design inheritance that can be corrected, and the corrections available are well documented: screen ahead of the secondary crusher, or add a dedicated third stage to eliminate circulating load. The economics are no longer marginal. A 25 percent gain in preparation output and a 15 percent reduction in preparation cost compound across every operating hour of every year that follows the retrofit. Set against that stream of savings, the capital outlay is best understood as buying back capacity the plant already paid for once, and never received.

When Screening Ahead Is Not Enough Front-loading the screening duty removes fines from the secondary crushing chamber, but it does not by itself resolve the second diagnosed cause: coarse screen oversize returning to a crusher sized for much larger feed. Where that circulating load remains the binding constraint, a third crushing stage is the appropriate correction. Its defining feature is simple: screened material no longer returns to the secondary crusher at all. The Revised Stage Sequence In a three-stage arrangement, the secondary crusher is relieved of the recirculating stream. Oversize from the screen is directed to a dedicated third-stage crusher whose chamber geometry, hammer configuration and speed are matched to the 2 to 20 mm feed it actually receives, instead of being forced through a machine designed around primary product. Because each stage now works on the size range it was engineered for, the plant recovers the three benefits that a misapplied single machine destroys: efficient energy transfer per strike, a stable and predictable product curve, and a screening operation that is no longer fighting a stream it cannot classify cleanly. Secondary Versus Third Stage: Matching Machine to Duty AspectSecondary Crusher on Coarse ReturnDedicated Third-Stage Crusher Feed size rangeMostly 2-20 mm, far below designMatched to the fines-removed oversize Impact efficiencyPoor, hammer bypasses small lumpsHigh, chamber grips the feed Circulating loadGrows with each passLargely eliminated Hourly output of the stageDepressed by repeated reworkRaised substantially Engineering Checks Before Committing Verify available headroom and footprint for a third machine and its drive. Confirm the third-stage product curve meets the fineness your forming line requires. Re-balance the screen aperture set so each deck sends material to the correct stage. Re-tier conveying and dust collection across three stages rather than two. What Changes on the Production Floor The most immediate and measurable change is on the secondary crusher itself. Relieved of the return stream, it operates within its intended load envelope, its hourly output rises sharply, and the whole preparation section stops queuing behind it. Downstream units that were previously starved of material begin to run at their own rated capacity, which is where much of the system-level gain is realised. Energy follows the same logic. Work that was previously repeated on the same material is now performed once, at the stage designed for it. Specific power consumption per tonne of prepared material falls even though one more machine has been added to the line. Choosing Between the Two Remedies Screening ahead and three-stage crushing are not competitors. The first is the lower-investment correction for fines contamination and suits plants with usable free space before the secondary stage. The second addresses circulating load directly and suits plants where the return stream is the dominant constraint, or where a finer final product is required. Both share the same underlying principle, and it is the principle that matters more than the specific layout: never ask one machine to do work that belongs to a stage it was not designed for.

Close the Gap at the Source If fines entering the secondary crushing chamber are the root of the capacity loss, then the most direct correction is to stop them entering at all. The first and most widely adopted remedy does exactly that: install a double-deck screen and move the screening duty ahead of the secondary crusher, rather than leaving it downstream. How the Revised Flowsheet Works In the corrected arrangement, material leaving the primary crusher is screened before it reaches the secondary stage. The double-deck configuration splits the stream into a fine fraction that bypasses secondary crushing entirely and a coarse fraction that proceeds to the crusher. The result, visible in the revised process diagram, is that only one type of material enters the secondary machine: screened oversize, with no fines mixed in and a substantially lower total mass flow. Two changes follow immediately. The cushioning effect disappears, because there is no fines bed to absorb impact energy around the lumps and hammers. And the volumetric load on the chamber drops, so each hammer strike meets material it can actually grip and break. What the Plant Gains ParameterOriginal Two-Stage FlowsheetScreening-Ahead Flowsheet Feed composition to secondary crusherMixed coarse plus finesScreened oversize only Impact energy efficiencyReduced by fines cushioningRestored to design level Mass flow through crusherFull primary productCoarse fraction only Total system throughputLimited by crusherRaised substantially The duty assigned to the secondary crusher is reduced on two fronts at once, by composition and by tonnage. That combination is why plants report a significant overall increase in the handling capacity of the whole crushing system, rather than a modest incremental gain. Implementation Points Worth Planning For Size the double-deck screen for the full primary product flow, not for the post-split fraction. Provide a clean bypass route for the fine fraction so it reaches mixing without re-entering the crusher. Review dust collection at the new screening point, since a dry fine stream is now liberated earlier in the line. Confirm that the crusher discharge and the bypass stream rejoin at a point where blending remains consistent. Why This Route Suits Existing Plants Screening ahead of crushing is attractive to operating plants because it does not require replacing the crusher. It inserts one well-understood unit operation into an existing line, keeps the installed crusher in service, and converts an overloaded machine into one working within its design envelope. It also addresses both diagnosed causes in a single move: the fines never reach the chamber, and the coarse return stream shrinks because the screen has already removed what did not need crushing. For plants where the layout allows an additional screening station, this is typically the shortest path from a bottleneck to a balanced line, and it is the option most frequently validated in retrofit projects.

Bottlenecks Are Usually Designed In When a brick plant discovers that its secondary crusher cannot keep up, the natural instinct is to blame maintenance, feed quality or the machine itself. In most cases, however, the shortfall was written into the project long before the first brick was fired. The crushing bottleneck is a design inheritance, and it can be traced back to three predictable root causes. Root Cause One: Capital Cost Chosen Over Process Logic The first cause dates back to the construction phase. Facing a fixed budget, project owners pursued the lowest possible investment and treated process rationality as a secondary concern. One consequence was that a single secondary crusher was asked to perform work it was never intended to perform: receiving unscreened primary product, absorbing a heavy fines load and simultaneously re-crushing screen oversize. Each of those duties is legitimate, but they belong to different stages of a properly sequenced line. Consolidating them into one machine delivers an attractive quotation and an unattractive operating cost for the next twenty years. Root Cause Two: A Market That Rewarded Volume Over Efficiency The second cause is structural rather than individual. During years of rapid expansion in capital construction, fired clay bricks were in short supply and margins were generous. Under those conditions, an inefficient process was still a profitable process. Slightly higher energy consumption, a lower hourly output and faster wear part replacement were absorbed without alarm, because the question was only how much profit a plant made, not whether it made any at all. That buffer has disappeared. The same inefficiency that was tolerable in a seller's market now sits directly on the cost line of every tonne produced. Root Cause Three: Aggressive Equipment Claims The third cause sits with some equipment suppliers. In order to win orders, certain manufacturers overstated machine capability, promoting the secondary crusher as a universal device able to handle any duty in a single pass. That narrative fitted neatly with the owner's preference for minimal investment, and the two together produced a decision that embedded a lasting operational risk into the plant. Root Causes and Their Long-Term Consequences Root CauseDecision Made at Project StageCost Carried in Operation Minimal investment priorityOne crusher assigned three incompatible dutiesPermanent capacity ceiling Seller's market mentalityInefficiency treated as acceptableHidden cost per tonne Overstated equipment claimsSpecification matched to sales copy, not to feed curvePremature wear and energy waste Warning Signs That a Plant Inherited the Flaw The secondary crusher is the only stage between primary crushing and screening. No screen is installed ahead of the secondary crusher. Screen oversize returns to the same machine that produced it. Output per hour has never matched the figure quoted at commissioning. From Diagnosis to Correction None of these root causes is a matter of operator competence, and none of them can be solved by working harder on the same layout. They are project-level decisions, which means they can also be corrected at project level through a re-sequenced flowsheet. Understanding where the flaw came from also explains why it is so persistent. A decision made to save capital in year one quietly becomes an operating penalty in every year that follows. The productive response is not recrimination but redesign: acknowledge the inherited constraint, quantify it, and close it with a proven process change.

The Complaint Every Brick Plant Shares In recent years, brick manufacturers have reported a long list of production problems, but one issue stands out as both the most severe and the most universal: the hourly output of the secondary crusher is simply too low. In plant after plant, that machine has become the bottleneck of the entire raw material preparation line, dragging down every other piece of equipment around it. The question worth asking is why such a widespread and expensive problem persists in an industry that has been forming and firing clay, shale and coal gangue for generations. The answer does not lie in the quality of the machinery. It lies in what is being fed into it. Cause One: Unscreened Feed Delivers a Heavy Load of Fines In the conventional two-stage flowsheet, material leaving the primary crusher passes directly into the secondary crusher without any screening step in between. As a result, the secondary machine receives a feed that already contains a large proportion of fine particles. Those fines are the hidden thief of throughput. Inside the crushing chamber, fines fill the space around the lumps of material and around the hammers themselves. Whether the hammer is striking a lump or a lump is being thrown against the breaker plate, that cloud of fine material acts as a cushion. It absorbs and distributes impact energy, softens the blow, and measurably reduces the reduction ratio actually achieved per pass. The machine keeps consuming power at its rated rate while delivering far less size reduction than its nameplate specification promised. Cause Two: Screen Oversize Returns to the Wrong Machine The second major contributor is the circulating load. After screening, the coarse oversize is typically returned to the secondary crusher for another pass. But this return stream is mostly in the 2 to 20 mm range, while the secondary crusher was designed around the product curve of the primary stage. Its geometry, hammer mass and chamber volume are all optimized for breaking considerably larger lumps. Using such a machine to reduce material below 20 mm is a straightforward waste of installed energy. Plant operators describe it vividly as cracking walnuts with an eight-pound sledgehammer. The crushing action degrades, the screening action degrades with it, and the plant ends up with the classic combination of high specific energy consumption and low tonnage. What the Chamber Actually Sees ConditionEffect on Impact EnergyResult on Output Fines packed around lumps and hammersEnergy absorbed and dispersed by the fines bedSharp drop in effective reduction Coarse return of 2-20 mm re-fedHammer strikes past the material without gripping itCirculating load grows, tonnage falls Both conditions combinedCompounding losses in the same chamberMachine becomes the plant bottleneck Three Practical Symptoms to Check on Site Rated motor current is drawn while output per hour stays well below specification. Screen undersize shows a persistent oversize fraction that keeps recirculating. Hammer and breaker plate wear accelerates without any corresponding gain in throughput. The Real Diagnosis: A Flawed Flowsheet, Not a Flawed Machine Both causes point to the same conclusion. The guilty party is the entry of fines into the secondary crushing stage, and once a plant is built on this arrangement, that entry is unavoidable. The problem is therefore structural. It is the process flowsheet itself that carries the defect, not the operator, not the maintenance team and not the crusher supplier's workmanship. Recognizing this distinction matters, because it changes the conversation from replacing equipment to correcting a layout. Plants that treat the symptom buy a bigger crusher and reproduce the same losses at a larger scale. Plants that treat the cause re-sequence the flowsheet, keep fines out of the impact chamber, and recover capacity they already paid for. The next step is to identify exactly where the flaw originated, and then to select between the two proven remedies: front-loading the screening duty, or adding a third crushing stage.

The Vice Chairman of the Standing Committee of the Provincial People’s Congress and the Secretary of the Party Committee of the China Environmental Protection Industry Association visited the Asia New Exhibition booth. They encouraged local enterprises in Henan to firmly grasp technological innovation, enhance industry market competitiveness, and support innovation-driven high-quality development.      

  Tunnel kiln is a continuously working thermal processing equipment, which is widely used in sintering bricks and tiles, ceramics and refractory materials, new materials and other industries. Its unique design and operation mode make it have significant advantages in improving energy efficiency, ensuring product quality and improving production efficiency.     (1) Single-channel linear type: This is the most commonly used basic structural form in sintered brick and tile factories. The structure is simple and easy to operate, suitable for small and medium-sized production lines.     (2) Multi-channel parallel linear type: By arranging multiple channels in parallel, the processing volume of products per unit time is increased, which is suitable for large-scale continuous production and has higher thermal energy utilization rate.   (3) Single-channel multi-jointed linear type: This is an innovative design that combines space optimization and energy-saving concepts, and can increase production capacity without increasing the floor space.     (4) "One-stop" linear type (baking kiln and drying kiln combined) Integrate the drying and baking processes into one, effectively recycle and utilize waste heat, and greatly improve the overall energy efficiency.   (5) Other kiln types: Circular mobile tunnel kiln, shuttle kiln, roller kiln, push plate kiln. These kiln types usually do not use kiln cars. They are suitable for specific products or process requirements and have a higher degree of automation and temperature control accuracy.     Except for the circular mobile tunnel kiln, roller kiln and push-plate kiln, the other linear tunnel kilns all require a kiln car to carry the products and move along the length of the kiln body to complete the entire firing process.